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Sample records for haploid male germ

  1. Dicer is required for haploid male germ cell differentiation in mice.

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    Hanna M Korhonen

    Full Text Available BACKGROUND: The RNase III endonuclease Dicer is an important regulator of gene expression that processes microRNAs (miRNAs and small interfering RNAs (siRNAs. The best-characterized function of miRNAs is gene repression at the post-transcriptional level through the pairing with mRNAs of protein-encoding genes. Small RNAs can also act at the transcriptional level by controlling the epigenetic status of chromatin. Dicer and other mediators of small RNA pathways are present in mouse male germ cells, and several miRNAs and endogenous siRNAs are expressed in the testis, suggesting that Dicer-dependent small RNAs are involved in the control of the precisely timed and highly organised process of spermatogenesis. PRINCIPAL FINDINGS: Being interested in the Dicer-mediated functions during spermatogenesis, we have analysed here a male germ cell-specific Dicer1 knockout mouse model, in which the deletion of Dicer1 takes place during early postnatal development in spermatogonia. We found that Dicer1 knockout testes were reduced in size and spermatogenesis within the seminiferous tubules was disrupted. Dicer1 knockout epididymides contained very low number of mature sperm with pronounced morphological abnormalities. Spermatogonial differentiation appeared unaffected. However, the number of haploid cells was decreased in knockout testes, and an increased number of apoptotic spermatocytes was observed. The most prominent defects were found during late haploid differentiation, and Dicer was demonstrated to be critical for the normal organization of chromatin and nuclear shaping of elongating spermatids. CONCLUSIONS/SIGNIFICANCE: We demonstrate that Dicer and Dicer-dependent small RNAs are imperative regulators of haploid spermatid differentiation and essential for male fertility.

  2. Human DAZL, DAZ and BOULE genes modulate primordial germ cell and haploid gamete formation

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    Kee, Kehkooi; Angeles, Vanessa T; Flores, Martha; Nguyen, Ha Nam; Pera, Renee A Reijo

    2009-01-01

    The leading cause of infertility in men and women is quantitative and qualitative defects in human germ cell (oocyte and sperm) development. Yet, it has not been possible to examine the unique developmental genetics of human germ cell formation and differentiation due to inaccessibility of germ cells during fetal development. Although several studies have shown that germ cells can be differentiated from mouse and human embryonic stem cells, human germ cells differentiated in these studies generally did not develop beyond the earliest stages1-8. Here we used a germ cell reporter to quantitate and isolate primordial germ cells derived from both male and female hESCs. Then, by silencing and overexpressing genes that encode germ cell-specific cytoplasmic RNA-binding proteins (not transcription factors), we modulated human germ cell formation and developmental progression. We observed that human DAZL (Deleted in AZoospermia-Like) functions in primordial germ cell formation, whereas closely-related genes, DAZ and BOULE, promote later stages of meiosis and development of haploid gametes. These results are significant to the generation of gametes for future basic science and potential clinical applications. PMID:19865085

  3. Molecular biological features of male germ cell differentiation

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    HIROSE, MIKA; TOKUHIRO, KEIZO; TAINAKA, HITOSHI; MIYAGAWA, YASUSHI; TSUJIMURA, AKIRA; OKUYAMA, AKIHIKO; NISHIMUNE, YOSHITAKE

    2007-01-01

    Somatic cell differentiation is required throughout the life of a multicellular organism to maintain homeostasis. In contrast, germ cells have only one specific function; to preserve the species by conveying the parental genes to the next generation. Recent studies of the development and molecular biology of the male germ cell have identified many genes, or isoforms, that are specifically expressed in the male germ cell. In the present review, we consider the unique features of male germ cell differentiation. (Reprod Med Biol 2007; 6: 1–9) PMID:29699260

  4. Mutability of germ cells of descedants of irradiated drosophila males

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    Fokina, T.L.; Vorobtsova, I.E.

    1987-01-01

    The increased frequency of random and radiation-induced mutation was registered in germ cells of drosophila irradiated male descendants of the first generation. The effect observed depended on of radiation dose delivered to parent males, test dose to posterity, type of mutation registered, and sex of the descendants under study

  5. Transcript levels of ten caste-related genes in adult diploid males of Melipona quadrifasciata (Hymenoptera, Apidae: a comparison with haploid males, queens and workers

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    Andreia A. Borges

    2011-01-01

    Full Text Available In Hymenoptera, homozygosity at the sex locus results in the production of diploid males. In social species, these pose a double burden by having low fitness and drawing resources normally spent for increasing the work force of a colony. Yet, diploid males are of academic interest as they can elucidate effects of ploidy (normal males are haploid, whereas the female castes, the queens and workers, are diploid on morphology and life history. Herein we investigated expression levels of ten caste-related genes in the stingless bee Melipona quadrifasciata, comparing newly emerged and 5-day-old diploid males with haploid males, queens and workers. In diploid males, transcript levels for dunce and paramyosin were increased during the first five days of adult life, while those for diacylglycerol kinase and the transcriptional co-repressor groucho diminished. Two general trends were apparent, (i gene expression patterns in diploid males were overall more similar to haploid ones and workers than to queens, and (ii in queens and workers, more genes were up-regulated after emergence until day five, whereas in diploid and especially so in haploid males more genes were down-regulated. This difference between the sexes may be related to longevity, which is much longer in females than in males.

  6. Transcript levels of ten caste-related genes in adult diploid males of Melipona quadrifasciata (Hymenoptera, Apidae) - A comparison with haploid males, queens and workers.

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    Borges, Andreia A; Humann, Fernanda C; Oliveira Campos, Lucio A; Tavares, Mara G; Hartfelder, Klaus

    2011-10-01

    In Hymenoptera, homozygosity at the sex locus results in the production of diploid males. In social species, these pose a double burden by having low fitness and drawing resources normally spent for increasing the work force of a colony. Yet, diploid males are of academic interest as they can elucidate effects of ploidy (normal males are haploid, whereas the female castes, the queens and workers, are diploid) on morphology and life history. Herein we investigated expression levels of ten caste-related genes in the stingless bee Melipona quadrifasciata, comparing newly emerged and 5-day-old diploid males with haploid males, queens and workers. In diploid males, transcript levels for dunce and paramyosin were increased during the first five days of adult life, while those for diacylglycerol kinase and the transcriptional co-repressor groucho diminished. Two general trends were apparent, (i) gene expression patterns in diploid males were overall more similar to haploid ones and workers than to queens, and (ii) in queens and workers, more genes were up-regulated after emergence until day five, whereas in diploid and especially so in haploid males more genes were down-regulated. This difference between the sexes may be related to longevity, which is much longer in females than in males.

  7. Generation of male differentiated germ cells from various types of stem cells.

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    Hou, Jingmei; Yang, Shi; Yang, Hao; Liu, Yang; Liu, Yun; Hai, Yanan; Chen, Zheng; Guo, Ying; Gong, Yuehua; Gao, Wei-Qiang; Li, Zheng; He, Zuping

    2014-06-01

    Infertility is a major and largely incurable disease caused by disruption and loss of germ cells. It affects 10-15% of couples, and male factor accounts for half of the cases. To obtain human male germ cells 'especially functional spermatids' is essential for treating male infertility. Currently, much progress has been made on generating male germ cells, including spermatogonia, spermatocytes, and spermatids, from various types of stem cells. These germ cells can also be used in investigation of the pathology of male infertility. In this review, we focused on advances on obtaining male differentiated germ cells from different kinds of stem cells, with an emphasis on the embryonic stem (ES) cells, the induced pluripotent stem (iPS) cells, and spermatogonial stem cells (SSCs). We illustrated the generation of male differentiated germ cells from ES cells, iPS cells and SSCs, and we summarized the phenotype for these stem cells, spermatocytes and spermatids. Moreover, we address the differentiation potentials of ES cells, iPS cells and SSCs. We also highlight the advantages, disadvantages and concerns on derivation of the differentiated male germ cells from several types of stem cells. The ability of generating mature and functional male gametes from stem cells could enable us to understand the precise etiology of male infertility and offer an invaluable source of autologous male gametes for treating male infertility of azoospermia patients. © 2014 Society for Reproduction and Fertility.

  8. Competition between the sperm of a single male can increase the evolutionary rate of haploid expressed genes.

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    Ezawa, Kiyoshi; Innan, Hideki

    2013-07-01

    The population genetic behavior of mutations in sperm genes is theoretically investigated. We modeled the processes at two levels. One is the standard population genetic process, in which the population allele frequencies change generation by generation, depending on the difference in selective advantages. The other is the sperm competition during each genetic transmission from one generation to the next generation. For the sperm competition process, we formulate the situation where a huge number of sperm with alleles A and B, produced by a single heterozygous male, compete to fertilize a single egg. This "minimal model" demonstrates that a very slight difference in sperm performance amounts to quite a large difference between the alleles' winning probabilities. By incorporating this effect of paternity-sharing sperm competition into the standard population genetic process, we show that fierce sperm competition can enhance the fixation probability of a mutation with a very small phenotypic effect at the single-sperm level, suggesting a contribution of sperm competition to rapid amino acid substitutions in haploid-expressed sperm genes. Considering recent genome-wide demonstrations that a substantial fraction of the mammalian sperm genes are haploid expressed, our model could provide a potential explanation of rapid evolution of sperm genes with a wide variety of functions (as long as they are expressed in the haploid phase). Another advantage of our model is that it is applicable to a wide range of species, irrespective of whether the species is externally fertilizing, polygamous, or monogamous. The theoretical result was applied to mammalian data to estimate the selection intensity on nonsynonymous mutations in sperm genes.

  9. Forskolin and the meiosis inducing substance synergistically initiate meiosis in fetal male germ cells

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    Byskov, A G; Fenger, M; Westergaard, L

    1993-01-01

    We have shown that Meiosis Inducing Substance (MIS) and forskolin synergistically and dose dependently induce meiosis in germ cells of cultured fetal mouse testes. We used a bioassay which consists of fetal mouse testes and ovaries cultured for 6 days. In this study MIS media are spent culture...... are fixed, squashed, and DNA-stained. In these preparations germ cells and somatic cells can be distinguished, and the number of germ cells in the different stages of meiosis is counted as is the number of somatic cells in mitosis. MIS activity is defined to be present in a medium when meiosis is induced...... in male germ cells during culture. We found that MIS media as well as forskolin induced meiosis in fetal male germ cells in a dose-dependent manner. In addition, MIS media and forskolin acted synergistically by inducing meiosis. Female germ cells seem to be unaffected by the various culture media...

  10. Dicer1 depletion in male germ cells leads to infertility due to cumulative meiotic and spermiogenic defects.

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    Yannick Romero

    Full Text Available BACKGROUND: Spermatogenesis is a complex biological process that requires a highly specialized control of gene expression. In the past decade, small non-coding RNAs have emerged as critical regulators of gene expression both at the transcriptional and post-transcriptional level. DICER1, an RNAse III endonuclease, is essential for the biogenesis of several classes of small RNAs, including microRNAs (miRNAs and endogenous small interfering RNAs (endo-siRNAs, but is also critical for the degradation of toxic transposable elements. In this study, we investigated to which extent DICER1 is required for germ cell development and the progress of spermatogenesis in mice. PRINCIPAL FINDINGS: We show that the selective ablation of Dicer1 at the early onset of male germ cell development leads to infertility, due to multiple cumulative defects at the meiotic and post-meiotic stages culminating with the absence of functional spermatozoa. Alterations were observed in the first spermatogenic wave and include delayed progression of spermatocytes to prophase I and increased apoptosis, resulting in a reduced number of round spermatids. The transition from round to mature spermatozoa was also severely affected, since the few spermatozoa formed in mutant animals were immobile and misshapen, exhibiting morphological defects of the head and flagellum. We also found evidence that the expression of transposable elements of the SINE family is up-regulated in Dicer1-depleted spermatocytes. CONCLUSIONS/SIGNIFICANCE: Our findings indicate that DICER1 is dispensable for spermatogonial stem cell renewal and mitotic proliferation, but is required for germ cell differentiation through the meiotic and haploid phases of spermatogenesis.

  11. The effects of humanin and its analogues on male germ cell apoptosis induced by chemotherapeutic drugs.

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    Jia, Yue; Ohanyan, Aikoui; Lue, Yan-He; Swerdloff, Ronald S; Liu, Peter Y; Cohen, Pinchas; Wang, Christina

    2015-04-01

    Human (HN) prevents stress-induced apoptosis in many cells/tissues. In this study we showed that HN ameliorated chemotherapy [cyclophosphamide (CP) and Doxorubicin (DOX)]-induced male germ cell apoptosis both ex vivo in seminiferous tubule cultures and in vivo in the testis. HN acts by several putative mechanisms via binding to: an IL-12 like trimeric membrane receptor; BAX; or insulin-like growth factor binding protein-3 (IGFBP-3, a proapoptotic factor). To understand the mechanisms of HN on male germ cell apoptosis, we studied five HN analogues including: HNG (HN-S14G, a potent agonist), HNG-F6A (no binding to IGFBP-3), HN-S7A (no self-dimerization), HN-C8P (no binding to BAX), and HN-L12A (a HN antagonist) on CP-induced male germ cell apoptosis in mice. CP-induced germ cell apoptosis was inhibited by HN, HNG, HNG-F6A, HN-S7A, and HN-C8P (less effective); but not by HN-L12A. HN-L12A, but not HN-S7A or HN-C8P, blocked the protective effect of HN against CP-induced male germ cell apoptosis. HN, HN-S7A, and HN-C8P restored CP-suppressed STAT3 phosphorylation. These results suggest that HN: (1) decreases DOX (ex vivo) and CP (in vivo) induced male germ cell apoptosis; (2) action is mediated by the membrane receptor/STAT3 with minor contribution by BAX-binding pathway; (3) self-dimerization or binding to IGFBP-3 may not be involved in HN's effect in testis. HN is an important molecule in the regulation of germ cell homeostasis after injury and agonistic analogues may be developed for treating male infertility or protection against chemotherapy side effects.

  12. Dearth and Delayed Maturation of Testicular Germ Cells in Fanconi Anemia E Mutant Male Mice.

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    Chun Fu

    Full Text Available After using a self-inactivating lentivirus for non-targeted insertional mutagenesis in mice, we identified a transgenic family with a recessive mutation that resulted in reduced fertility in homozygous transgenic mice. The lentiviral integration site was amplified by inverse PCR. Sequencing revealed that integration had occurred in intron 8 of the mouse Fance gene, which encodes the Fanconi anemia E (Fance protein. Fanconi anemia (FA proteins play pivotal roles in cellular responses to DNA damage and Fance acts as a molecular bridge between the FA core complex and Fancd2. To investigate the reduced fertility in the mutant males, we analyzed postnatal development of testicular germ cells. At one week after birth, most tubules in the mutant testes contained few or no germ cells. Over the next 2-3 weeks, germ cells accumulated in a limited number of tubules, so that some tubules contained germ cells around the full periphery of the tubule. Once sufficient numbers of germ cells had accumulated, they began to undergo the later stages of spermatogenesis. Immunoassays revealed that the Fancd2 protein accumulated around the periphery of the nucleus in normal developing spermatocytes, but we did not detect a similar localization of Fancd2 in the Fance mutant testes. Our assays indicate that although Fance mutant males are germ cell deficient at birth, the extant germ cells can proliferate and, if they reach a threshold density, can differentiate into mature sperm. Analogous to previous studies of FA genes in mice, our results show that the Fance protein plays an important, but not absolutely essential, role in the initial developmental expansion of the male germ line.

  13. Whole-genome sequencing of spermatocytic tumors provides insights into the mutational processes operating in the male germline

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    Giannoulatou, Eleni; Maher, Geoffrey J; Ding, Zhihao

    2017-01-01

    Adult male germline stem cells (spermatogonia) proliferate by mitosis and, after puberty, generate spermatocytes that undertake meiosis to produce haploid spermatozoa. Germ cells are under evolutionary constraint to curtail mutations and maintain genome integrity. Despite constant turnover...

  14. Male germ cell-specific expression of a novel Patched-domain containing gene Ptchd3

    International Nuclear Information System (INIS)

    Fan Jun; Akabane, Hiroto; Zheng Xuehai; Zhou Xuan; Zhang Li; Liu Qiang; Zhang Yonglian; Yang Jing; Zhu Guozhang

    2007-01-01

    The Hedgehog (Hh) signaling pathway plays an important role in various biological processes, including pattern formation, cell fate determination, proliferation, and differentiation. Hh function is mediated through its membrane receptor Patched. Herein, we have characterized a novel Patched-domain containing gene Ptchd3 in mouse. Messenger RNA of Ptchd3 was exclusively detected in the testis, and existed in two isoforms Ptchd3a and Ptchd3b. The expression of these two mRNA isoforms was shown to be developmentally regulated in testes, and specifically found in male germ cells. Further analysis revealed that the Ptchd3 protein was located on the midpiece of mouse, rat and human sperm. Collectively, these results indicate that Ptchd3 is a novel male germ cell-specific gene and may be involved in the Hh signaling to regulate sperm development and/or sperm function

  15. Flexible adaptation of male germ cells from female iPSCs of endangered Tokudaia osimensis.

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    Honda, Arata; Choijookhuu, Narantsog; Izu, Haruna; Kawano, Yoshihiro; Inokuchi, Mizuho; Honsho, Kimiko; Lee, Ah-Reum; Nabekura, Hiroki; Ohta, Hiroshi; Tsukiyama, Tomoyuki; Ohinata, Yasuhide; Kuroiwa, Asato; Hishikawa, Yoshitaka; Saitou, Mitinori; Jogahara, Takamichi; Koshimoto, Chihiro

    2017-05-01

    In mammals, the Y chromosome strictly influences the maintenance of male germ cells. Almost all mammalian species require genetic contributors to generate testes. An endangered species, Tokudaia osimensis , has a unique sex chromosome composition XO/XO, and genetic differences between males and females have not been confirmed. Although a distinctive sex-determining mechanism may exist in T. osimensis , it has been difficult to examine thoroughly in this rare animal species. To elucidate the discriminative sex-determining mechanism in T. osimensis and to find a strategy to prevent its possible extinction, we have established induced pluripotent stem cells (iPSCs) and derived interspecific chimeras using mice as the hosts and recipients. Generated iPSCs are considered to be in the so-called "true naïve" state, and T. osimensis iPSCs may contribute as interspecific chimeras to several different tissues and cells in live animals. Surprisingly, female T. osimensis iPSCs not only contributed to the female germ line in the interspecific mouse ovary but also differentiated into spermatocytes and spermatids that survived in the adult interspecific mouse testes. Thus, T. osimensis cells have high sexual plasticity through which female somatic cells can be converted to male germline cells. These findings suggest flexibility in T. osimensis cells, which can adapt their germ cell sex to the gonadal niche. The probable reduction of the extinction risk of an endangered species through the use of iPSCs is indicated by this study.

  16. SOX4 regulates gonad morphogenesis and promotes male germ cell differentiation in mice.

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    Zhao, Liang; Arsenault, Michel; Ng, Ee Ting; Longmuss, Enya; Chau, Tevin Chui-Ying; Hartwig, Sunny; Koopman, Peter

    2017-03-01

    The group C SOX transcription factors SOX4, -11 and -12 play important and mutually overlapping roles in development of a number of organs. Here, we examined the role of SoxC genes during gonadal development in mice. All three genes were expressed in developing gonads of both sexes, predominantly in somatic cells, with Sox4 being most strongly expressed. Sox4 deficiency resulted in elongation of both ovaries and testes, and an increased number of testis cords. While female germ cells entered meiosis normally, male germ cells showed reduced levels of differentiation markers Nanos2 and Dnmt3l and increased levels of pluripotency genes Cripto and Nanog, suggesting that SOX4 may normally act to restrict the pluripotency period of male germ cells and ensure their proper differentiation. Finally, our data reveal that SOX4 (and, to a lesser extent, SOX11 and -12) repressed transcription of the sex-determining gene Sox9 via an upstream testis-specific enhancer core (TESCO) element in fetal gonads, raising the possibility that SOXC proteins may function as transcriptional repressors in a context-dependent manner. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Male Hypogonadism and Germ Cell Loss Caused by a Mutation in Polo-Like Kinase 4

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    Harris, Rebecca M.; Weiss, Jeffrey

    2011-01-01

    The genetic etiologies of male infertility remain largely unknown. To identify genes potentially involved in spermatogenesis and male infertility, we performed genome-wide mutagenesis in mice with N-ethyl-N-nitrosourea and identified a line with dominant hypogonadism and patchy germ cell loss. Genomic mapping and DNA sequence analysis identified a novel heterozygous missense mutation in the kinase domain of Polo-like kinase 4 (Plk4), altering an isoleucine to asparagine at residue 242 (I242N). Genetic complementation studies using a gene trap line with disruption in the Plk4 locus confirmed that the putative Plk4 missense mutation was causative. Plk4 is known to be involved in centriole formation and cell cycle progression. However, a specific role in mammalian spermatogenesis has not been examined. PLK4 was highly expressed in the testes both pre- and postnatally. In the adult, PLK4 expression was first detected in stage VIII pachytene spermatocytes and was present through step 16 elongated spermatids. Because the homozygous Plk4I242N/I242N mutation was embryonic lethal, all analyses were performed using the heterozygous Plk4+/I242N mice. Testis size was reduced by 17%, and histology revealed discrete regions of germ cell loss, leaving only Sertoli cells in these defective tubules. Testis cord formation (embryonic day 13.5) was normal. Testis histology was also normal at postnatal day (P)1, but germ cell loss was detected at P10 and subsequent ages. We conclude that the I242N heterozygous mutation in PLK4 is causative for patchy germ cell loss beginning at P10, suggesting a role for PLK4 during the initiation of spermatogenesis. PMID:21791561

  18. 35S induced dominant lethals in male germ cells of mouse

    International Nuclear Information System (INIS)

    Satyanarayana Reddy, K.; Reddy, P.D.; Reddi, O.S.

    1977-01-01

    (CBA female x C 3 H/He male) F 1 males born to 35 S (20 μCi) treated animals during major organogenesis period were tested for dominant lethal mutations at maturity. The pre-implantation loss showed an increase from 6.88% in the control to 10.92% in 35 S treated animals. Similarly the post-implantation loss has increased from 3.96% (control) to 7.40%. As a result of the increased pre- and post-losses the total loss showed a significant increase (17.51%) in F 1 males born to 35 S treated animals when compared to controls (10.57%). Thus the results clearly show that 35 S is mutagenic in male germ cells of mouse. (author)

  19. Digestive and regenerative cells in the midgut of haploid and diploid males of the stingless bee Melipona quadrifasciata anthidioides (Hymenoptera: Apidae

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    Kenner M. Fernandes

    2012-10-01

    Full Text Available In eusocial bees, workers and queens are diploid (2n, whereas males are haploid (n. However, in some species, including the stingless bee Melipona quadrifasciata anthidioides Lepeletier, 1836, 2n males arise from fertilized eggs resulting from the crossing between a queen and her brother. In the present study, we provide a comparative analysis of the digestive and regenerative cells in n and 2n pupae and adult males of M. quadrifasciata anthidioides. In n and 2n pupae and adult males, the number of regenerative cells/nest was similar. In n and 2n pupae, the mean number of digestive cells/midgut area was 2076 ± 0.60, whereas in adults it was 1234 ± 1.42 digestive cells/midgut area. The nuclear area of the digestive cells was also similar in both n and 2n adult males (~154 µm² and smaller in pupae (~91 µm²; this variation might be a result of DNA amplification in digestive cells during bee development. The results from our current study provide further understanding of the morphological and physiological aspects of the digestive tract of bees and show that the ploidy difference between n and 2n male stages does not affect the number of digestive and regenerative cells in the midgut of M. quadrifasciata anthidioides.

  20. Transgenic mice produced by retroviral transduction of male germ-line stem cells

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    Nagano, Makoto; Brinster, Clayton J.; Orwig, Kyle E.; Ryu, Buom-Yong; Avarbock, Mary R.; Brinster, Ralph L.

    2001-01-01

    Male germ-line stem cells are the only cell type in postnatal mammals that have the capability to self-renew and to contribute genes to the next generation. Genetic modification of these cells would provide an opportunity to study the biology of their complex self-renewal and differentiation processes, as well as enable the generation of transgenic animals in a wide range of species. Although retroviral vectors have been used as an efficient method to introduce genes into a variety of cell ty...

  1. Disrupting the male germ line to find infertility and contraception targets.

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    Archambeault, Denise R; Matzuk, Martin M

    2014-05-01

    Genetically-manipulated mouse models have become indispensible for broadening our understanding of genes and pathways related to male germ cell development. Until suitable in vitro systems for studying spermatogenesis are perfected, in vivo models will remain the gold standard for inquiry into testicular function. Here, we discuss exciting advances that are allowing researchers faster, easier, and more customizable access to their mouse models of interest. Specifically, the trans-NIH Knockout Mouse Project (KOMP) is working to generate knockout mouse models of every gene in the mouse genome. The related Knockout Mouse Phenotyping Program (KOMP2) is performing systematic phenotypic analysis of this genome-wide collection of knockout mice, including fertility screening. Together, these programs will not only uncover new genes involved in male germ cell development but also provide the research community with the mouse models necessary for further investigations. In addition to KOMP/KOMP2, another promising development in the field of mouse models is the advent of CRISPR (clustered regularly interspaced short palindromic repeat)-Cas technology. Utilizing 20 nucleotide guide sequences, CRISPR/Cas has the potential to introduce sequence-specific insertions, deletions, and point mutations to produce null, conditional, activated, or reporter-tagged alleles. CRISPR/Cas can also successfully target multiple genes in a single experimental step, forgoing the multiple generations of breeding traditionally required to produce mouse models with deletions, insertions, or mutations in multiple genes. In addition, CRISPR/Cas can be used to create mouse models carrying variants identical to those identified in infertile human patients, providing the opportunity to explore the effects of such mutations in an in vivo system. Both the KOMP/KOMP2 projects and the CRISPR/Cas system provide powerful, accessible genetic approaches to the study of male germ cell development in the mouse. A

  2. Protective Effects of Thymoquinone against Methotrexate-Induced Germ Cell Apoptosis in Male Mice

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    Fatemeh Sheikhbahaei

    2016-12-01

    Full Text Available Background: Toxic effects of anti-cancer and other drugs on the normal tissues could be reduced by the herbal plants and their fractions. This study investigated the protective effect of thymoquinone (TQ as a fraction of Nigella sativa on methotrexate (MTX- induced germ cell apoptosis in male mice. Materials and Methods: In this experimental study, thirty male Balb/c mice were divided randomly into 5 groups (n=6. A single dose of MTX (20 mg/kg and different concentrations of TQ were administrated for 4 consecutive days. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL assay was performed on paraffin embedded tissue sections to analysis the occurrence of apoptosis in the testis. Reverse transcription polymerase chain reaction (RT-PCR of apoptosis-related genes was performed with RNA extracted from testes of the mice. Statistical analysis was done using one-way ANOVA. Results: In the MTX group, there was a significant increase in morphologic sign of germ cell degeneration of tubules (48 ± 0.6%, apoptotic index (AI; 2.3 ± 0.6%, as well as mRNA expression of p53 (P=0.008, caspase 8 (P=0.002, caspase 3 (P=0.005, caspase 9 (P=0.000, bax (P=0.004 and the ratio of bax/bcl-2 (P=0.000, whereas there was an decrease in the expression of bcl-2 (P=0.003, as compared to control group. In MTX+TQ groups, the data showed that different concentrations of TQ could improve the harmful effects caused by the MTX. The best protective effects were achieved in MTX+TQ (10 mg/kg. Conclusion: TQ protects testicular germ cell against MTX-induced apoptosis by affecting related genes regulation.

  3. Expression of arf tumor suppressor in spermatogonia facilitates meiotic progression in male germ cells.

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    Michelle L Churchman

    2011-07-01

    Full Text Available The mammalian Cdkn2a (Ink4a-Arf locus encodes two tumor suppressor proteins (p16(Ink4a and p19(Arf that respectively enforce the anti-proliferative functions of the retinoblastoma protein (Rb and the p53 transcription factor in response to oncogenic stress. Although p19(Arf is not normally detected in tissues of young adult mice, a notable exception occurs in the male germ line, where Arf is expressed in spermatogonia, but not in meiotic spermatocytes arising from them. Unlike other contexts in which the induction of Arf potently inhibits cell proliferation, expression of p19(Arf in spermatogonia does not interfere with mitotic cell division. Instead, inactivation of Arf triggers germ cell-autonomous, p53-dependent apoptosis of primary spermatocytes in late meiotic prophase, resulting in reduced sperm production. Arf deficiency also causes premature, elevated, and persistent accumulation of the phosphorylated histone variant H2AX, reduces numbers of chromosome-associated complexes of Rad51 and Dmc1 recombinases during meiotic prophase, and yields incompletely synapsed autosomes during pachynema. Inactivation of Ink4a increases the fraction of spermatogonia in S-phase and restores sperm numbers in Ink4a-Arf doubly deficient mice but does not abrogate γ-H2AX accumulation in spermatocytes or p53-dependent apoptosis resulting from Arf inactivation. Thus, as opposed to its canonical role as a tumor suppressor in inducing p53-dependent senescence or apoptosis, Arf expression in spermatogonia instead initiates a salutary feed-forward program that prevents p53-dependent apoptosis, contributing to the survival of meiotic male germ cells.

  4. Differential expression of conserved germ line markers and delayed segregation of male and female primordial germ cells in a hermaphrodite, the leech helobdella.

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    Cho, Sung-Jin; Vallès, Yvonne; Weisblat, David A

    2014-02-01

    In sexually reproducing animals, primordial germ cells (PGCs) are often set aside early in embryogenesis, a strategy that minimizes the risk of genomic damage associated with replication and mitosis during the cell cycle. Here, we have used germ line markers (piwi, vasa, and nanos) and microinjected cell lineage tracers to show that PGC specification in the leech genus Helobdella follows a different scenario: in this hermaphrodite, the male and female PGCs segregate from somatic lineages only after more than 20 rounds of zygotic mitosis; the male and female PGCs share the same (mesodermal) cell lineage for 19 rounds of zygotic mitosis. Moreover, while all three markers are expressed in both male and female reproductive tissues of the adult, they are expressed differentially between the male and female PGCs of the developing embryo: piwi and vasa are expressed preferentially in female PGCs at a time when nanos is expressed preferentially in male PGCs. A priori, the delayed segregation of male and female PGCs from somatic tissues and from one another increases the probability of mutations affecting both male and female PGCs of a given individual. We speculate that this suite of features, combined with a capacity for self-fertilization, may contribute to the dramatically rearranged genome of Helobdella robusta relative to other animals.

  5. Activated Cdc42 kinase regulates Dock localization in male germ cells during Drosophila spermatogenesis.

    Science.gov (United States)

    Abdallah, Abbas M; Zhou, Xin; Kim, Christine; Shah, Kushani K; Hogden, Christopher; Schoenherr, Jessica A; Clemens, James C; Chang, Henry C

    2013-06-15

    Deregulation of the non-receptor tyrosine kinase ACK1 (Activated Cdc42-associated kinase) correlates with poor prognosis in cancers and has been implicated in promoting metastasis. To further understand its in vivo function, we have characterized the developmental defects of a null mutation in Drosophila Ack, which bears a high degree of sequence similarity to mammalian ACK1 but lacks a CRIB domain. We show that Ack, while not essential for viability, is critical for sperm formation. This function depends on Ack tyrosine kinase activity and is required cell autonomously in differentiating male germ cells at or after the spermatocyte stage. Ack associates predominantly with endocytic clathrin sites in spermatocytes, but disruption of Ack function has no apparent effect on clathrin localization and receptor-mediated internalization of Boss (Bride of sevenless) protein in eye discs. Instead, Ack is required for the subcellular distribution of Dock (dreadlocks), the Drosophila homolog of the SH2- and SH3-containing adaptor protein Nck. Moreover, Dock forms a complex with Ack, and the localization of Dock in male germ cells depends on its SH2 domain. Together, our results suggest that Ack-dependent tyrosine phosphorylation recruits Dock to promote sperm differentiation. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Genotoxicity evaluation of buprofezin, petroleum oil and profenofos in somatic and germ cells of male mice.

    Science.gov (United States)

    Fahmy, M A; Abdalla, E F

    1998-01-01

    The two pest control agents, buprofezin and petroleum oil (Super Royal), were tested to evaluate their potential mutagenicity, in comparison with the organophosphorus insecticide profenofos. Chromosomal aberration analysis was used in both somatic and germ cells of male mice. Single oral treatment at three different dose levels (1/16, 1/8 and 1/4 LD50) for each insecticide induced an increase in the percentage of chromosomal aberrations in bone-marrow cells 24 h post-treatment, indicating a dose-dependent relationship. The percentage of chromosomal aberrations reached 23 +/- 0.73, 10.5 +/- 0.64 and 15 +/- 1.4 after treatment with the highest tested dose of profenofos, buprofezin and Super Royal, respectively. Such percentages did not exceed the corresponding value of the positive control, mitomycin C (29.2 +/- 0.69). The percentage of chromosomal aberrations induced by the different doses of profenofos was still highly significant even after excluding gaps. The same trend of results was noticed only at the highest tested dose of buprofezin and Super Royal. With respect to germ cells, profenofos is also a potent inducer of chromosomal aberrations in 1ry spermatocytes, giving percentages of 14 +/- 1.3 and 19 +/- 1.6 at the two higher doses of 4.25 and 8.5 mg kg(-1) body wt., respectively. Buprofezin and Super Royal had no significant effect on mouse spermatocytes at the tested concentrations. The various types of induced aberrations were examined and recorded in both somatic and germ cells. In conclusion, the present investigation indicates that the two pest control agents buprofezin and Super Royal are relatively much safer compounds than the conventional organophosphorus insecticides.

  7. Effects of chemical-induced DNA damage on male germ cells

    Energy Technology Data Exchange (ETDEWEB)

    Holme, J.A.; Bjoerge, C.; Trbojevic, M.; Olsen, A.K.; Brunborg, G.; Soederlund, E.J. [National Inst. of Public Health, Oslo (Norway). Dept. of Environmental Medicine; Bjoeras, M.; Seeberg, E. [National Hospital, Oslo (Norway). Dept. of Microbiology; Scholz, T.; Dybing, E.; Wiger, R. [National Hospital, Oslo (Norway). Inst. for Surgical Research and Surgical Dept. B

    1998-12-31

    Several recent studies indicate declines in sperm production, as well as increases in the incidence of genitourinary abnormalities such as testicular cancer, cryptorchidism and hypospadias. It is not known if these effects are due to exposure to chemical pollutants or if other ethiological factors are involved. Animal studies indicate that chemicals will induce such effects by various genetic, epigenetic or non-genetic mechanisms. Recently, much attention has been focused on embryonic/fetal exposure to oestrogen-mimicking chemicals (Toppari et al., 1996). However, the possibility that chemicals may cause reproductive toxicity by other mechanisms such as interactions with DNA, should not be ignored. DNA damage in germ cells may lead to the production of mutated spermatozoa, which in turn may result in spontaneous abortions, malformations and/or genetic defects in the offspring. Regarding the consequences of DNA alterations for carcinogenesis it is possible that genetic damage may occur germ cells, but the consequences are not expressed until certain genetic events occur in postnatal life. Transmission of genetic risk is best demonstrated by cancer-prone disorders such as hereditary retinoblastoma and the Li-Fraumeni syndrome. A number of experiments indicate that germ cells and proliferating cells may be particularly sensitive to DNA damaging agents compared to other cells. Furthermore, several lines of evidence have indicated that one of the best documented male reproductive toxicants, 1,2-dibrome-3-chloropropane (DBCP), causes testicular toxicity through DNA damage. It is possible that testicular cells at certain maturational stages are more subject to DNA damage, have less efficient DNA repair, or have different thresholds for initiating apoptosis following DNA damage than other cell types. (orig.)

  8. Genetic effects of combined chemical-X-ray treatments in male mouse germ cells

    International Nuclear Information System (INIS)

    Cattanach, B.M.; Rasberry, C.

    1987-01-01

    Several studies have shown that the yield of genetic damage induced by radiation in male mouse germ cells can be modified by chemical treatments. Pre-treatments with radio-protecting agents have given contradictory results but this appears to be largely attributable to the different germ cell stages tested and dependent upon the level of radiation damage induced. Pre-treatments which enhance the yield of genetic damage have been reported although, as yet, no tests have been conducted with radio-sensitizers. Another form of interaction between chemicals and radiation is specifically found with spermatogonial stem cells. Chemicals that kill cells can, by population depletion, substantially and predictably modify the genetic response to subsequent radiation exposure over a period of several days, or even weeks. Enhancement and reduction in the genetic yield can be attained, dependent upon the interval between treatments, with the modification also varying with the type of genetic damage scored. Post-treatment with one chemical (TEM) has been shown to reduce the genetic response to radiation exposure. (author)

  9. Direct Differentiation of Human Pluripotent Stem Cells into Haploid Spermatogenic Cells

    Directory of Open Access Journals (Sweden)

    Charles A. Easley, IV

    2012-09-01

    Full Text Available Human embryonic stem cells (hESCs and induced pluripotent stem cells (hiPSCs have been shown to differentiate into primordial germ cells (PGCs but not into spermatogonia, haploid spermatocytes, or spermatids. Here, we show that hESCs and hiPSCs differentiate directly into advanced male germ cell lineages, including postmeiotic, spermatid-like cells, in vitro without genetic manipulation. Furthermore, our procedure mirrors spermatogenesis in vivo by differentiating PSCs into UTF1-, PLZF-, and CDH1-positive spermatogonia-like cells; HIWI- and HILI-positive spermatocyte-like cells; and haploid cells expressing acrosin, transition protein 1, and protamine 1 (proteins that are uniquely found in spermatids and/or sperm. These spermatids show uniparental genomic imprints similar to those of human sperm on two loci: H19 and IGF2. These results demonstrate that male PSCs have the ability to differentiate directly into advanced germ cell lineages and may represent a novel strategy for studying spermatogenesis in vitro.

  10. DIFFERENTIAL SENSITIVITY OF MALE GERM CELLS TO MAINSTREAM AND SIDESTREAM TOBACCO SMOKE IN THE MOUSE

    Energy Technology Data Exchange (ETDEWEB)

    Polyzos, Aris; Schmid, Thomas Ernst; Pina-Guzman, Belem; Quintanilla-Vega, Betzabet; Marchetti, Francesco

    2009-03-13

    Cigarette smoking in men has been associated with increased chromosomal abnormalities in sperm and with increased risks for spontaneous abortions, birth defects and neonatal death. Little is known, however, about the reproductive consequences of paternal exposure to second-hand smoke. We used a mouse model to investigate the effects of paternal exposure to sidestream (SS) smoke, the main constituent of second-hand smoke, on the genetic integrity and function of sperm, and to determine whether male germ cells were equally sensitive to mainstream (MS) and SS smoke. A series of sperm DNA quality and reproductive endpoints were investigated after exposing male mice for two weeks to MS or SS smoke. Our results indicated that: (i) only SS smoke significantly affected sperm motility; (ii) only MS smoke induced DNA strand breaks in sperm; (iii) both MS and SS smoke increased sperm chromatin structure abnormalities; and (iv) MS smoke affected both fertilization and the rate of early embryonic development, while SS smoke affected fertilization only. These results show that MS and SS smoke have differential effects on the genetic integrity and function of sperm and provide further evidence that male exposure to second-hand smoke, as well as direct cigarette smoke, may diminish a couple's chance for a successful pregnancy and the birth of a healthy baby.

  11. Regulation of mitosis-meiosis transition by the ubiquitin ligase β-TrCP in male germ cells.

    Science.gov (United States)

    Nakagawa, Tadashi; Zhang, Teng; Kushi, Ryo; Nakano, Seiji; Endo, Takahiro; Nakagawa, Makiko; Yanagihara, Noriko; Zarkower, David; Nakayama, Keiko

    2017-11-15

    The mitosis-meiosis transition is essential for spermatogenesis. Specific and timely downregulation of the transcription factor DMRT1, and consequent induction of Stra8 expression, is required for this process in mammals, but the molecular mechanism has remained unclear. Here, we show that β-TrCP, the substrate recognition component of an E3 ubiquitin ligase complex, targets DMRT1 for degradation and thereby controls the mitosis-meiosis transition in mouse male germ cells. Conditional inactivation of β-TrCP2 in male germ cells of β-TrCP1 knockout mice resulted in sterility due to a lack of mature sperm. The β-TrCP-deficient male germ cells did not enter meiosis, but instead underwent apoptosis. The induction of Stra8 expression was also attenuated in association with the accumulation of DMRT1 at the Stra8 promoter in β-TrCP-deficient testes. DMRT1 contains a consensus β-TrCP degron sequence that was found to bind β-TrCP. Overexpression of β-TrCP induced the ubiquitylation and degradation of DMRT1. Heterozygous deletion of Dmrt1 in β-TrCP-deficient spermatogonia increased meiotic cells with a concomitant reduction of apoptosis. Collectively, our data indicate that β-TrCP regulates the transition from mitosis to meiosis in male germ cells by targeting DMRT1 for degradation. © 2017. Published by The Company of Biologists Ltd.

  12. Male germ cell apoptosis and epigenetic histone modification induced by Tripterygium wilfordii Hook F.

    Directory of Open Access Journals (Sweden)

    Ji Xiong

    Full Text Available Multiglycosides of Tripterygium wilfordii Hook f (GTW, a Chinese herb-derived medicine used as a remedy for rheumatoid arthritis, are considered to be a reversible anti-fertility drug affecting the mammalian spermatids. However, the mechanism behind this effect is still unknown. To study the possible mechanism behind the impact of GTW on spermatogenesis, we administered 4 groups of 4-week-old male mice with different doses of GTW. We found a dose-dependent decrease in the number of germ cells after 40 days of GTW treatment, and an increase in apoptotic cells from the low-dose to the high-dose group. During this same period the dimethylated level of histone H3 lysine 9 (H3K9me2 in GTW-treated testes germ cells declined. Additionally, spermatogonial stem cells (SSCs from 6-day-old mice were isolated to evaluate the possible effect of GTW or triptolide on development of SSCs. We found a significantly higher incidence of apoptosis and lower dimethylation level of H3K9me2 in the SSCs of GTW or triptolide treatment than in controls. Thus, these data suggest that the GTW-induced apoptosis might be responsible for the fertility impairment in mice. This damage could be traced back to the early stages of spermatogenesis. GTW also affected the epigenetic modification of H3K9 in spermatogenesis. Molecular dynamics simulation suggested that triptolide and dimethylated or trimethylated H3K9 might have similar interaction mechanisms with EED (embryonic ectoderm development. These candidate activation mechanisms provide the first glimpse into the pathway of GTW-induced gonad toxicity, which is crucial for further research and clinical application.

  13. HP1γ function is required for male germ cell survival and spermatogenesis

    Directory of Open Access Journals (Sweden)

    Brown Jeremy P

    2010-04-01

    Full Text Available Abstract Background HP1 proteins are conserved components of eukaryotic constitutive heterochromatin. In mammals, there are three genes that encode HP1-like proteins, termed HP1α, HP1β and HP1γ, which have a high degree of homology This paper describes for the first time, to our knowledge, the physiological function of HP1γ using a gene-targeted mouse. Results While targeting the Cbx3 gene (encoding the HP1γ protein with a conditional targeting vector, we generated a hypomorphic allele (Cbx3hypo, which resulted in much reduced (barely detectable levels of HP1γ protein. Homozygotes for the hypomorphic allele (Cbx3hypo/hypo are rare, with only 1% of Cbx3hypo/hypo animals reaching adulthood. Adult males exhibit a severe hypogonadism that is associated with a loss of germ cells, with some seminiferous tubules retaining only the supporting Sertoli cells (Sertoli cell-only phenotype. The percentage of seminiferous tubules that are positive for L1 ORF1 protein (ORF1p in Cbx3hypo/hypo testes is greater than that for wild-type testes, indicating that L1 retrotransposon silencing is reversed, leading to ectopic expression of ORF1p in Cbx3hypo/hypo germ cells. Conclusions The Cbx3 gene product (the HP1γ protein has a non-redundant function during spermatogenesis that cannot be compensated for by the other two HP1 isotypes. The Cbx3hypo/hypo spermatogenesis defect is similar to that found in Miwi2 and Dnmt3L mutants. The Cbx3 gene-targeted mice generated in this study provide an appropriate model for the study of HP1γ in transposon silencing and parental imprinting.

  14. Reciprocal translocations in germ cells of male mice receiving external γ-irradiation

    International Nuclear Information System (INIS)

    Bayrakova, A.; Filev, G.; Baev, I.

    1987-01-01

    Experiments were undertaken in which yields were recorded of reciprocal translocations in germ cells of male mice exposed to 0.9 Gy of γ-radiation at dose rates ranging from 6.14 x 10 -3 to 6.14 x 10 2 mGy/min (6 levels); comparisons were made with data published up to 1985 from similar studies using other fixed doses. To do this, translocation yields were expressed as relative yields (F) and their relationship to the dose rate (P) for the individual fixed doses was represented by an equation of the type: F = α + β log P. For most of the equations, the regression coefficients were in good agreement and a single relationship was obtained to represent them. From the analysis performed it follows that, within the 0.6-6.0 Gy dose range, the pattern of the F vs. P relationship is unaffected by the dose. This supports the initial assumption that for the dose range up to 6.0 Gy the dose response for the reciprocal translocation yield is a non-threshold straight-line relationship. (Auth.)

  15. Effects of chemical and physical agents on recombination events in cells of the germ line of male and female Drosophila melanogaster.

    Science.gov (United States)

    Würgler, F E

    1991-01-01

    Genotoxic agents can induce mutations as well as recombination in the genetic material. The fruit fly Drosophila melanogaster was one of the first assay systems to test physical and chemical agents for recombinogenic effects. Such effects can be observed in cells of the germ line as well as in somatic cells. At present information is available on 54 agents, among them 48 chemicals that have been tested in cells of the germ line of males and/or females. Effects on meiotic recombination in female germ cells cannot simply be classified as positive or negative since for a number of agents, depending on the chromosome region studied, recombination frequencies may be increased, unaffected or decreased. The male germ line of D. melanogaster represents a unique situation because meiotic recombination does not occur. Among 25 agents tested in male germ cells 24 did induce male recombination, among them alkylating, intercalating and cross-linking agents, direct-acting ones as well as compounds needing metabolic activation. With several compounds the frequency of induced recombination is highest in the heterochromatic regions near the centromeres. In brood pattern analyses, e.g., after exposure of adult males to ionizing radiation, the first appearance of crossover progeny is indicative of the sampling of exposed spermatocytes. In premeiotic cells of the male and the female germ line mitotic recombination can occur. Upon clonal expansion of the recombinant cells, clusters of identical crossovers can be observed.

  16. Prenatal and early postnatal NOAEL-dose clothianidin exposure leads to a reduction of germ cells in juvenile male mice.

    Science.gov (United States)

    Yanai, Shogo; Hirano, Tetsushi; Omotehara, Takuya; Takada, Tadashi; Yoneda, Naoki; Kubota, Naoto; Yamamoto, Anzu; Mantani, Youhei; Yokoyama, Toshifumi; Kitagawa, Hiroshi; Hoshi, Nobuhiko

    2017-07-07

    Neonicotinoids are pesticides used worldwide. They bind to insect nicotinic acetylcholine receptors (nAChRs) with high affinity. We previously reported that clothianidin (CTD), one of the latest neonicotinoids, reduced antioxidant expression and induced germ cell death in the adult testis of vertebrates. Here, we investigated the male reproductive toxicity of prenatal and early postnatal exposure to CTD, because it is likely that developmental exposure more severely affects the testis compared to adults due to the absence of the blood-testis barrier. Pregnant C57BL/6 mice were given water gel blended with CTD (0, 10 or 50 mg/kg/day; no-observed-adverse-effect-level [NOAEL for mice]: 47.2 mg/kg/day) between gestational day 1 and 14 days post-partum. We then examined the testes of male offspring at postnatal day 14. The testis weights and the numbers of germ cells per seminiferous tubule were decreased in the CTD-50 group, and abnormal tubules containing no germ cells appeared. Nevertheless, the apoptotic cell number and proliferative activity were not significantly different between the control and CTD-exposed groups. There were no significant differences in the androgen-related parameters, such as the Leydig cell volume per testis, the Sertoli cell number and the tubule diameter. The present study is the first demonstration that in utero and lactational exposures to CTD at around the NOAEL for mice reduce the germ cell number, but our findings suggest that these exposures do not affect steroidogenesis in Leydig cells during prenatal or early postnatal life.

  17. Analysis of the cytoskeleton organization and its possible functions in male earthworm germ-line cysts equipped with a cytophore.

    Science.gov (United States)

    Małota, Karol; Świątek, Piotr

    2016-10-01

    We studied the organization of F-actin and the microtubular cytoskeleton in male germ-line cysts in the seminal vesicles of the earthworm Dendrobaena veneta using light, fluorescent and electron microscopy along with both chemically fixed tissue and life cell imaging. Additionally, in order to follow the functioning of the cytoskeleton, we incubated the cysts in colchicine, nocodazole, cytochalasin D and latrunculin A. The male germ-line cells of D. veneta are interconnected via stable intercellular bridges (IB), and form syncytial cysts. Each germ cell has only one IB that connects it to the anuclear central cytoplasmic mass, the cytophore. During the studies, we analyzed the cytoskeleton in spermatogonial, spermatocytic and spermatid cysts. F-actin was detected in the cortical cytoplasm and forms distinct rings in the IBs. The arrangement of the microtubules changed dynamically during spermatogenesis. The microtubules are distributed evenly in whole spermatogonial and spermatocytic cysts; however, they primarily accumulate within the IBs in spermatogonia. In early spermatids, microtubules pass through the IBs and are present in whole cysts. During spermatid elongation, the microtubules form a manchette while they are absent in the cytophore and in the IBs. Use of cytoskeletal drugs did not alter the general morphology of the cysts. Detectable effects-the occurrence of nuclei in the late spermatids and manchette fragments in the cytophore-were observed only after incubation in nocodazole. Our results suggest that the microtubules are responsible for cytoplasmic/organelle transfer between the germ cells and the cytophore during spermatogenesis and for the positioning of the spermatid nuclei.

  18. Distinct and Cooperative Roles of amh and dmrt1 in Self-Renewal and Differentiation of Male Germ Cells in Zebrafish.

    Science.gov (United States)

    Lin, Qiaohong; Mei, Jie; Li, Zhi; Zhang, Xuemei; Zhou, Li; Gui, Jian-Fang

    2017-11-01

    Spermatogenesis is a fundamental process in male reproductive biology and depends on precise balance between self-renewal and differentiation of male germ cells. However, the regulative factors for controlling the balance are poorly understood. In this study, we examined the roles of amh and dmrt1 in male germ cell development by generating their mutants with Crispr/Cas9 technology in zebrafish. Amh mutant zebrafish displayed a female-biased sex ratio, and both male and female amh mutants developed hypertrophic gonads due to uncontrolled proliferation and impaired differentiation of germ cells. A large number of proliferating spermatogonium-like cells were observed within testicular lobules of the amh -mutated testes, and they were demonstrated to be both Vasa- and PH3-positive. Moreover, the average number of Sycp3- and Vasa-positive cells in the amh mutants was significantly lower than in wild-type testes, suggesting a severely impaired differentiation of male germ cells. Conversely, all the dmrt1 -mutated testes displayed severe testicular developmental defects and gradual loss of all Vasa-positive germ cells by inhibiting their self-renewal and inducing apoptosis. In addition, several germ cell and Sertoli cell marker genes were significantly downregulated, whereas a prominent increase of Insl3-positive Leydig cells was revealed by immunohistochemical analysis in the disorganized dmrt1 -mutated testes. Our data suggest that amh might act as a guardian to control the balance between proliferation and differentiation of male germ cells, whereas dmrt1 might be required for the maintenance, self-renewal, and differentiation of male germ cells. Significantly, this study unravels novel functions of amh gene in fish. Copyright © 2017 by the Genetics Society of America.

  19. Differentiation in Stem Cell Lineages and in Life: Explorations in the Male Germ Line Stem Cell Lineage.

    Science.gov (United States)

    Fuller, Margaret T

    2016-01-01

    I have been privileged to work on cellular differentiation during a great surge of discovery that has revealed the molecular mechanisms and genetic regulatory circuitry that control embryonic development and adult tissue maintenance and repair. Studying the regulation of proliferation and differentiation in the male germ line stem cell lineage has allowed us investigate how the developmental program imposes layers of additional controls on fundamental cellular processes like cell cycle progression and gene expression to give rise to the huge variety of specialized cell types in our bodies. We are beginning to understand how local signals from somatic support cells specify self-renewal versus differentiation in the stem cell niche at the apical tip of the testis. We are discovering the molecular events that block cell proliferation and initiate terminal differentiation at the switch from mitosis to meiosis-a signature event of the germ cell program. Our work is beginning to reveal how the developmental program that sets up the dramatic new cell type-specific transcription program that prepares germ cells for meiotic division and spermatid differentiation is turned on when cells become spermatocytes. I have had the privilege of working with incredible students, postdocs, and colleagues who have discovered, brainstormed, challenged, and refined our science and our ideas of how developmental pathways and cellular mechanisms work together to drive differentiation. © 2016 Elsevier Inc. All rights reserved.

  20. Interaction of NANOS2 and NANOS3 with different components of the CNOT complex may contribute to the functional differences in mouse male germ cells

    OpenAIRE

    Atsushi Suzuki; Yuki Niimi; Yumiko Saga

    2014-01-01

    ABSTRACT NANOS2 and NANOS3 belong to the Nanos family of proteins that contain a conserved zinc finger domain, which consists of two consecutive CCHC-type zinc finger motifs, and contribute to germ cell development in mice. Previous studies indicate that there are redundant and distinct functions of these two proteins. NANOS2 rescues NANOS3 functions in the maintenance of primordial germ cells, whereas NANOS3 fails to replace NANOS2 functions in the male germ cell pathway. However, the lack o...

  1. Multi-modality treatment in males with advanced malignant germ cell tumours

    International Nuclear Information System (INIS)

    Fossaa, S.D.; Klepp, O.; Ous, S.; Lien, H.; Stenwig, J.T.; Abeler, V.; Eliasson, G.; Hoest, H.

    1984-01-01

    After chemotherapy with cis-platinum, vinblastine and bleomycin, 33 surgical prosedures were performed in 29 patients with advanced malignant germ-cell tumours. The tumour masses could be completely resected macroscopially in 26 patients. Patients with fibros/necrosis or completely resected mature teratoma had an excellent prognosis, whereas only 5 of the 11 patients with vital malignant tumour survived in spite of second-line treatment with chemotherapy/radiotherapy. Preoperatively elevated serum levels of AFP, β-HCG and/or LDH indicated the presence of residual germ cell tumour. Eight of 14 patients were rendered tumour-free by radiotherapy given as second- or third-line treatment. In general, tumour masses, remaining after cis-platinum-based induction chemotherapy should be resected as completely as possible even in the case of mature teratoma or fibrosis/necrosis. Radiotherapy should be considered as second -and thirdline treatment

  2. Complete depletion of primordial germ cells in an All-female fish leads to Sex-biased gene expression alteration and sterile All-male occurrence.

    Science.gov (United States)

    Liu, Wei; Li, Shi-Zhu; Li, Zhi; Wang, Yang; Li, Xi-Yin; Zhong, Jian-Xiang; Zhang, Xiao-Juan; Zhang, Jun; Zhou, Li; Gui, Jian-Fang

    2015-11-18

    Gynogenesis is one of unisexual reproduction modes in vertebrates, and produces all-female individuals with identical genetic background. In sexual reproduction vertebrates, the roles of primordial germ cells on sexual dimorphism and gonadal differentiation have been largely studied, and two distinct functional models have been proposed. However, the role of primordial germ cells remains unknown in unisexual animals, and it is also unclear whether the functional models in sexual reproduction animals are common in unisexual animals. To solve these puzzles, we attempt to utilize the gynogenetic superiority of polyploid Carassius gibelio to create a complete germ cell-depleted gonad model by a similar morpholino-mediated knockdown approach used in other examined sexual reproduction fishes. Through the germ cell-depleted gonad model, we have performed comprehensive and comparative transcriptome analysis, and revealed a complete alteration of sex-biased gene expression. Moreover, the expression alteration leads to up-regulation of testis-biased genes and down-regulation of ovary-biased genes, and results in the occurrence of sterile all-males with testis-like gonads and secondary sex characteristics in the germ cell-depleted gynogenetic Carassius gibelio. Our current results have demonstrated that unisexual gynogenetic embryos remain keeping male sex determination information in the genome, and the complete depletion of primordial germ cells in the all-female fish leads to sex-biased gene expression alteration and sterile all-male occurrence.

  3. Changes in the profile of simple mucin-type O-glycans and polypeptide GalNAc-transferases in human testis and testicular neoplasms are associated with germ cell maturation and tumour differentiation

    DEFF Research Database (Denmark)

    Rajpert-De Meyts, E; Poll, S N; Goukasian, I

    2007-01-01

    Testicular germ cell tumours (TGCT) exhibit remarkable ability to differentiate into virtually all somatic tissue types. In this study, we investigated changes in mucin-type O-glycosylation, which have been associated with somatic cell differentiation and cancer. Expression profile of simple mucin......-glycosylation pattern in haploid germ cells suggests a role in their maturation or egg recognition/fertilization warranting further studies in male infertility, whereas the findings in TGCT provide new diagnostic tools and support our hypothesis that testicular cancer is a developmental disease of germ cell...

  4. Mediastinal mixed germ cell tumor in an infertile male with Klinefelter syndrome:A case report and literature review

    Directory of Open Access Journals (Sweden)

    Dinesh Pradhan

    2015-01-01

    Full Text Available Klinefelter syndrome (KS is a well-documented abnormality of the sex chromosome, with an incidence of 1 in 600 newborn males. It is characterized by a 47, XXY or a mosaic karyotype, hypergonadotrophic hypogonadism, infertility, reduced body hair, gynecomastia, and tall stature. Different neoplasms such as breast, testicular, and lymphoreticular malignancies may occur in 1% to2% of the cases with KS. Herein we describe a case of mediastinal mixed germ cell tumor (GCT in a 40-year-old male with KS. Interestingly, this case also had mitral valve prolapse, and an incidental papillary microcarcinoma of the thyroid gland. In view of the presence of pulmonary nodules, antemortem differential diagnoses considered were mycobacterial infection, lymphoma, thymic carcinoma, and a primary/metastatic neoplasm of the lung. As GCT was not considered, the serum markers of a GCT were not performed. The diagnosis of this rare mediastinal mixed GCT with KS was made at autopsy.

  5. RAB10 Interacts with the Male Germ Cell-Specific GTPase-Activating Protein during Mammalian Spermiogenesis

    Directory of Open Access Journals (Sweden)

    Ying-Hung Lin

    2017-01-01

    Full Text Available According to recent estimates, 2%–15% of couples are sterile, and approximately half of the infertility cases are attributed to male reproductive factors. However, the reasons remain undefined in approximately 25% of male infertility cases, and most infertility cases exhibit spermatogenic defects. Numerous genes involved in spermatogenesis still remain unknown. We previously identified Male Germ Cells Rab GTPase-Activating Proteins (MGCRABGAPs through cDNA microarray analysis of human testicular tissues with spermatogenic defects. MGCRABGAP contains a conserved RABGAP catalytic domain, TBC (Tre2/Bub2/Cdc16. RABGAP family proteins regulate cellular function (e.g., cytoskeletal remodeling, vesicular trafficking, and cell migration by inactivating RAB proteins. MGCRABGAP is a male germ cell-specific protein expressed in elongating and elongated spermatids during mammalian spermiogenesis. The purpose of this study was to identify proteins that interact with MGCRABGAP during mammalian spermiogenesis using a proteomic approach. We found that MGCRABGAP exhibited GTPase-activating bioability, and several MGCRABGAP interactors, possible substrates (e.g., RAB10, RAB5C, and RAP1, were identified using co-immunoprecipitation (co-IP and nano liquid chromatography-mass spectrometry/mass spectrometry (nano LC-MS/MS. We confirmed the binding ability between RAB10 and MGCRABGAP via co-IP. Additionally, MGCRABGAP–RAB10 complexes were specifically colocalized in the manchette structure, a critical structure for the formation of spermatid heads, and were slightly expressed at the midpiece of mature spermatozoa. Based on these results, we propose that MGCRABGAP is involved in mammalian spermiogenesis by modulating RAB10.

  6. Switching of dominant retrotransposon silencing strategies from posttranscriptional to transcriptional mechanisms during male germ-cell development in mice.

    Directory of Open Access Journals (Sweden)

    Kota Inoue

    2017-07-01

    Full Text Available Mammalian genomes harbor millions of retrotransposon copies, some of which are transpositionally active. In mouse prospermatogonia, PIWI-interacting small RNAs (piRNAs combat retrotransposon activity to maintain the genomic integrity. The piRNA system destroys retrotransposon-derived RNAs and guides de novo DNA methylation at some retrotransposon promoters. However, it remains unclear whether DNA methylation contributes to retrotransposon silencing in prospermatogonia. We have performed comprehensive studies of DNA methylation and polyA(+ RNAs (transcriptome in developing male germ cells from Pld6/Mitopld and Dnmt3l knockout mice, which are defective in piRNA biogenesis and de novo DNA methylation, respectively. The Dnmt3l mutation greatly reduced DNA methylation levels at most retrotransposons, but its impact on their RNA abundance was limited in prospermatogonia. In Pld6 mutant germ cells, although only a few retrotransposons exhibited reduced DNA methylation, many showed increased expression at the RNA level. More detailed analysis of RNA sequencing, nascent RNA quantification, profiling of cleaved RNA ends, and the results obtained from double knockout mice suggest that PLD6 works mainly at the posttranscriptional level. The increase in retrotransposon expression was larger in Pld6 mutants than it was in Dnmt3l mutants, suggesting that RNA degradation by the piRNA system plays a more important role than does DNA methylation in prospermatogonia. However, DNA methylation had a long-term effect: hypomethylation caused by the Pld6 or Dnmt3l mutation resulted in increased retrotransposon expression in meiotic spermatocytes. Thus, posttranscriptional silencing plays an important role in the early stage of germ cell development, then transcriptional silencing becomes important in later stages. In addition, intergenic and intronic retrotransposon sequences, in particular those containing the antisense L1 promoters, drove ectopic expression of nearby

  7. MIWI2 as an Effector of DNA Methylation and Gene Silencing in Embryonic Male Germ Cells

    Directory of Open Access Journals (Sweden)

    Kanako Kojima-Kita

    2016-09-01

    Full Text Available During the development of mammalian embryonic germ cells, global demethylation and de novo DNA methylation take place. In mouse embryonic germ cells, two PIWI family proteins, MILI and MIWI2, are essential for the de novo DNA methylation of retrotransposons, presumably through PIWI-interacting RNAs (piRNAs. Although piRNA-associated MIWI2 has been reported to play critical roles in the process, its molecular mechanisms have remained unclear. To identify the mechanism, transgenic mice were produced; they contained a fusion protein of MIWI2 and a zinc finger (ZF that recognized the promoter region of a type A LINE-1 gene. The ZF-MIWI2 fusion protein brought about DNA methylation, suppression of the type A LINE-1 gene, and a partial rescue of the impaired spermatogenesis of MILI-null mice. In addition, ZF-MIWI2 was associated with the proteins involved in DNA methylation. These data indicate that MIWI2 functions as an effector of de novo DNA methylation of the retrotransposon.

  8. Factor VIII (F8) inversions in severe hemophilia A: Male germ cell origin and diagnosis with RT-PCR

    Energy Technology Data Exchange (ETDEWEB)

    Antonarakis, S.E. [Geneva Medical School (Switzerland)]|[Johns Hopkins School of Medicine, Baltimore, MD (United States); Rossiter, J.P. [Johns Hopkins School of Medicine, Baltimore, MD (United States); Young, M. [Geneva Medical School (Switzerland)] [and others

    1994-09-01

    The Factor VIII (F8) gene, which is defective in hemophilia A, is located in the most telomeric megabase of Xq. Inversions due to intrachromosomal homologous recombination between mispaired copies of gene A located within intron 22 of the gene and about 500 kb telomeric to it account for nearly half of the cases of severe hemophilia A. We hypothesized that pairing of Xq with its homolog inhibits the inversion process, and that therefore the event originates predominantly in male germ cells. In all 21 informative cases in which the inversion originated in a maternal grandparent, DNA polymorphism analysis using markers within or very closely linked to F8, determined that it occurred in the male germline. In addition, all but one of 56 mothers of sporadic cases due to inversions were carriers. The data indicate that the F8 gene inversions leading to severe hemophilia A occur almost exclusively in male germ cells. The mean age of maternal grandfathers at the birth of their carrier daughters was 29.9 years (13 cases), i.e. not different from the mean paternal age in the general population, supporting the hypothesis that the inversions occur in meiosis. The inversions can be diagnosed by Southern blot analysis. For more rapid diagnosis we have used RT-PCR of RNA ectopically expressed in blood. Oligonucleotides were used to PCR amplify, after the initial RT reaction of RNA samples using random hexamers, either the normal transcript (F8 exons 21 to 24;312 bp product) or the novel abnormal transcript that is generated after the inversion. Both type 1 and 2 inversions can be recognized in affecteds and carriers by the presence of the diagnostic PcR product of 248 bp. Correct diagnoses were made in samples from 6 patients and 2 carriers with type 1 inversions, 2 patients and 2 carriers with type 2 inversions and 5 normal controls.

  9. Evaluation of the mutagenic potential of Cochlospermum regium in Drosophila melanogaster male germ cells

    Directory of Open Access Journals (Sweden)

    Nunes Wanderlene Blanco

    2003-01-01

    Full Text Available During the last few decades the search for medical treatments based on alternative medicine has increased significantly, making knowledge of the plants commonly used as folk medicines extremely important. The plant Cochlospermum regium, a member of the Cochlospermaceae found in the Brazilian cerrado (a type of savanna, is known to have high depurative activity and to be effective not only in treating skin problems such as pimples, boils and blotches but also in curing gastritis and ulcers. We prepared aqueous extracts using 13, 19 and 25 gL-1 of dried C. regium root and investigated these extracts for possible mutagenic effects on Drosophila melanogaster germ cells. Mutagenesis was assessed using the ring-X loss (RXL test which can detect chromosome mosaicism, partial loss of the ring X chromosome and chromosome non-disjunction. Our results showed that at the concentrations tested C. regium extracts did not induce ring-X loss in D. melanogaster.

  10. Automatic analysis of flow cytometric DNA histograms from irradiated mouse male germ cells

    International Nuclear Information System (INIS)

    Lampariello, F.; Mauro, F.; Uccelli, R.; Spano, M.

    1989-01-01

    An automatic procedure for recovering the DNA content distribution of mouse irradiated testis cells from flow cytometric histograms is presented. First, a suitable mathematical model is developed, to represent the pattern of DNA content and fluorescence distribution in the sample. Then a parameter estimation procedure, based on the maximum likelihood approach, is constructed by means of an optimization technique. This procedure has been applied to a set of DNA histograms relative to different doses of 0.4-MeV neutrons and to different time intervals after irradiation. In each case, a good agreement between the measured histograms and the corresponding fits has been obtained. The results indicate that the proposed method for the quantitative analysis of germ cell DNA histograms can be usefully applied to the study of the cytotoxic and mutagenic action of agents of toxicological interest such as ionizing radiations.18 references

  11. Protective effect of vitamins C and E on Gamma radiation induced Genetic injuries in male mice germ cells

    International Nuclear Information System (INIS)

    Anwar, W.A.; El-Daway, H.A.E.; Tawfik, S.S.M.

    1999-01-01

    The effects of vitamins C and E on meiotic chromosomal metaphase-8 at diakinesis of the mouse to 3 Gy of whole body gamma- irradiation were studied. These vitamins were injected intraperitoneally as acute doses 2 hr before irradiation. Both vitamins significantly reduced the frequencies of chromosomal aberration in spermatic germ cells. The protective effect of vitamin E was greater than that afforded by vitamin C. A combined treatment of both vitamins resulted in additional protection over that offered by each vitamine alone. In all animal groups the most frequent aberration found was translocation in the from of either ring four (R IV) or chain four (C IV). The percentage of each or them was significantly increased in male mice sacrificed after 15 days post-irradiation. Other types of aberrations as autosomal univalent, X-Gamma univalent and polyploidy were rarely present

  12. The differentiation potential of adipose tissue-derived mesenchymal stem cells into cell lineage related to male germ cells

    Directory of Open Access Journals (Sweden)

    P. Bräunig

    Full Text Available ABSTRACT The adipose tissue is a reliable source of Mesenchymal stem cells (MSCs showing a higher plasticity and transdifferentiation potential into multilineage cells. In the present study, adipose tissue-derived mesenchymal stem cells (AT-MSCs were isolated from mice omentum and epididymis fat depots. The AT-MSCs were initially compared based on stem cell surface markers and on the mesodermal trilineage differentiation potential. Additionally, AT-MSCs, from both sources, were cultured with differentiation media containing retinoic acid (RA and/or testicular cell-conditioned medium (TCC. The AT-MSCs expressed mesenchymal surface markers and differentiated into adipogenic, chondrogenic and osteogenic lineages. Only omentum-derived AT-MSCs expressed one important gene marker related to male germ cell lineages, after the differentiation treatment with RA. These findings reaffirm the importance of adipose tissue as a source of multipotent stromal-stem cells, as well as, MSCs source regarding differentiation purpose.

  13. Genomic profiling of rice sperm cell transcripts reveals conserved and distinct elements in the flowering plant male germ lineage.

    Science.gov (United States)

    Russell, Scott D; Gou, Xiaoping; Wong, Chui E; Wang, Xinkun; Yuan, Tong; Wei, Xiaoping; Bhalla, Prem L; Singh, Mohan B

    2012-08-01

    Genomic assay of sperm cell RNA provides insight into functional control, modes of regulation, and contributions of male gametes to double fertilization. Sperm cells of rice (Oryza sativa) were isolated from field-grown, disease-free plants and RNA was processed for use with the full-genome Affymetrix microarray. Comparison with Gene Expression Omnibus (GEO) reference arrays confirmed expressionally distinct gene profiles. A total of 10,732 distinct gene sequences were detected in sperm cells, of which 1668 were not expressed in pollen or seedlings. Pathways enriched in male germ cells included ubiquitin-mediated pathways, pathways involved in chromatin modeling including histones, histone modification and nonhistone epigenetic modification, and pathways related to RNAi and gene silencing. Genome-wide expression patterns in angiosperm sperm cells indicate common and divergent themes in the male germline that appear to be largely self-regulating through highly up-regulated chromatin modification pathways. A core of highly conserved genes appear common to all sperm cells, but evidence is still emerging that another class of genes have diverged in expression between monocots and dicots since their divergence. Sperm cell transcripts present at fusion may be transmitted through plasmogamy during double fertilization to effect immediate post-fertilization expression of early embryo and (or) endosperm development. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  14. Therapeutic Effect of Taurine on Gamma Radiation Induced Genetic Injuries in Germ Cells of Male Mice and Their Male Offspring

    International Nuclear Information System (INIS)

    El-Dawy, H.A.; Tawfik, S.S.; El-Khafif, M.A.; Ragab, M.H.

    2005-01-01

    The efficiency of taurine therapy for treatment of male mice exposed to a dose of (3 Gy) whole body gamma irradiation and their male offspring was studied after administration taurine 1% in drinking water post irradiation. Administration of taurine therapy resulted in a significant decrease in the effect of irradiation on chromosomal aberrations in irradiated animals and their male offspring. The efficiency of taurine as radio therapeutic agent is greatly dependent on its chemical properties as strong oxidants scavenger and biological activities as osmoregulator and membrane stabilizer. The probable mechanism of taurine therapy was discussed

  15. Expression of the neurotransmitter-synthesizing enzyme glutamic acid decarboxylase in male germ cells.

    Science.gov (United States)

    Persson, H; Pelto-Huikko, M; Metsis, M; Söder, O; Brene, S; Skog, S; Hökfelt, T; Ritzén, E M

    1990-09-01

    The gene encoding glutamic acid decarboxylase (GAD), the key enzyme in the synthesis of the inhibitory neurotransmitter gamma-aminobutyric acid, is shown to be expressed in the testis of several different species. Nucleotide sequence analysis of a cDNA clone isolated from the human testis confirmed the presence of GAD mRNA in the testis. The major GAD mRNA in the testis was 2.5 kilobases. Smaller amounts of a 3.7-kilobase mRNA with the same size as GAD mRNA in the brain was also detected in the testis. In situ hybridization using a GAD-specific probe revealed GAD mRNA expressing spermatocytes and spermatids located in the middle part of rat seminiferous tubules. Studies on the ontogeny of GAD mRNA expression showed low levels of GAD mRNA in testes of prepubertal rats, with increasing levels as sexual maturation is reached, compatible with GAD mRNA expression in germ cells. In agreement with this, fractionation of cells from the rat seminiferous epithelium followed by Northern (RNA) blot analysis showed the highest levels of GAD mRNA associated with spermatocytes and spermatids. Evidence for the presence of GAD protein in the rat testis was obtained from the demonstration of GAD-like immunoreactivity in seminiferous tubules, predominantly at a position where spermatids and spermatozoa are found. Furthermore, GAD-like immunoreactivity was seen in the midpiece of ejaculated human spermatozoa, the part that is responsible for generating energy for spermatozoan motility.

  16. Juvenile spermatogonial depletion (jsd): a genetic defect of germ cell proliferation of male mice.

    Science.gov (United States)

    Beamer, W G; Cunliffe-Beamer, T L; Shultz, K L; Langley, S H; Roderick, T H

    1988-05-01

    Adult C57BL/6J male mice homozygous for the mutant gene, juvenile spermatogonial depletion (jsd/jsd), show azoosper4ia and testes reduced to one-third normal size, but are otherwise phenotypically normal. In contrast, adult jsd/jsd females are fully fertile. This feature facilitated mapping the jsd gene to the centromeric end of chromosome 1; the gene order is jsd-Isocitrate dehydrogenase-1 (Idh-1)-Peptidase-3 (Pep-3). Analysis of testicular histology from jsd/jsd mice aged 3-10 wk revealed that these mutant mice experience one wave of spermatogenesis, but fail to continue mitotic proliferation of type A spermatogonial cells at the basement membrane. As a consequence, histological sections of testes from mutant mice aged 8-52 wk showed tubules populated by modest numbers of Sertoli cells, with only an occasional spermatogonial cell. Some sperm with normal morphology and motility were observed in epididymides of 6.5- but not in 8-wk or older mutants. Treatment with retinol failed to alter the loss of spermatogenesis in jsd/jsd mice. Analyses of serum hormones of jsd/jsd males showed that testosterone levels were normal at all ages--a finding corroborated by normal seminal vesicle and vas deferens weights, whereas serum follicle-stimulating hormone levels were significantly elevated in mutant mice from 4 to 20 wk of age. We hypothesize the jsd/jsd male may be deficient in proliferative signals from Sertoli cells that are needed for spermatogenesis.

  17. Haploid rice plants in mutation studies

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, S [Institute of Radiation Breeding, Ministry of Agriculture and Forestry, Ohmiya, Ibaraki-ken (Japan)

    1970-03-01

    Studies were made on chlorophyll-deficient sectors and diploid-like sectors in haploid rice plants exposed to chronic gamma irradiation, and on germinal mutations in diploid strains derived from the haploid plants. The induction and elimination of somatic mutations in haploid plants and the occurrence of drastic germinal mutations in diploid strains from haploid plants are discussed. (author)

  18. Interaction of NANOS2 and NANOS3 with different components of the CNOT complex may contribute to the functional differences in mouse male germ cells

    Directory of Open Access Journals (Sweden)

    Atsushi Suzuki

    2014-11-01

    Full Text Available NANOS2 and NANOS3 belong to the Nanos family of proteins that contain a conserved zinc finger domain, which consists of two consecutive CCHC-type zinc finger motifs, and contribute to germ cell development in mice. Previous studies indicate that there are redundant and distinct functions of these two proteins. NANOS2 rescues NANOS3 functions in the maintenance of primordial germ cells, whereas NANOS3 fails to replace NANOS2 functions in the male germ cell pathway. However, the lack of a conditional allele of Nanos3 has hampered delineation of each contribution of NANOS2 and NANOS3 to the male germ cell pathway. In addition, the molecular mechanism underlying the distinct functions of these proteins remains unexplored. Here, we report an unexpected observation of a transgenic mouse line expressing a NANOS2 variant harboring mutations in the zinc finger domain. Transcription of Nanos2 and Nanos3 was strongly compromised in the presence of this transgene, which resulted in the mimicking of the Nanos2/Nanos3 double-null condition in the male gonad. In these transgenic mice, P-bodies involved in RNA metabolism had disappeared and germ cell differentiation was more severely affected than that in Nanos2-null mice, indicating that NANOS3 partially substitutes for NANOS2 functions. In addition, similar to NANOS2, we found that NANOS3 associated with the CCR4-NOT deadenylation complex but via a direct interaction with CNOT8, unlike CNOT1 in the case of NANOS2. This alternate interaction might account for the molecular basis of the functional redundancy and differences in NANOS2 and NANOS3 functions.

  19. Stage-specific damage to synaptonemal complexes and metaphase chromosomes induced by X rays in male mouse germ cells

    International Nuclear Information System (INIS)

    Backer, L.C.; Sontag, M.R.; Allen, J.W.

    1991-01-01

    Synaptonemal complexes (SCs) reveal mutagen-induced effects in germ cell meiotic chromosomes. The study was aimed at characterizing relationships between SC and metaphase I chromosome damage following radiation exposure at various stages of spermatogenesis. Male mice were irradiated with doses of 0, 2, or 4 Gy, and spermatocytes were harvested at times consistent with earlier exposures as spermatogonial stem cells, preleptotene cells (premeiotic DNA synthesis), or meiotic prophase cells. After stem-cell exposure, twice as many rearrangements were observed in SCs as in metaphase I chromosomes. Irradiation during premeiotic DNA synthesis resulted in dose-related increases in SC breakage and rearrangements (including novel forms) and in metaphase chromosomal aberrations. Following prophase exposure, various types and levels of SC and metaphase damage were observed. Irradiation of zygotene cells led to high frequencies of chromosome multivalents in metaphase I without a correspondingly high level of damage in preceding prophase SCs. Thus, irradiation of premeiotic and meiotic cells results in variable relationships between SC and metaphase chromosome damage

  20. Negative regulation of ciliary length by ciliary male germ cell-associated kinase (Mak) is required for retinal photoreceptor survival.

    Science.gov (United States)

    Omori, Yoshihiro; Chaya, Taro; Katoh, Kimiko; Kajimura, Naoko; Sato, Shigeru; Muraoka, Koichiro; Ueno, Shinji; Koyasu, Toshiyuki; Kondo, Mineo; Furukawa, Takahisa

    2010-12-28

    Cilia function as cell sensors in many organs, and their disorders are referred to as "ciliopathies." Although ciliary components and transport machinery have been well studied, regulatory mechanisms of ciliary formation and maintenance are poorly understood. Here we show that male germ cell-associated kinase (Mak) regulates retinal photoreceptor ciliary length and subcompartmentalization. Mak was localized both in the connecting cilia and outer-segment axonemes of photoreceptor cells. In the Mak-null retina, photoreceptors exhibit elongated cilia and progressive degeneration. We observed accumulation of intraflagellar transport 88 (IFT88) and IFT57, expansion of kinesin family member 3A (Kif3a), and acetylated α-tubulin signals in the Mak-null photoreceptor cilia. We found abnormal rhodopsin accumulation in the Mak-null photoreceptor cell bodies at postnatal day 14. In addition, overexpression of retinitis pigmentosa 1 (RP1), a microtubule-associated protein localized in outer-segment axonemes, induced ciliary elongation, and Mak coexpression rescued excessive ciliary elongation by RP1. The RP1 N-terminal portion induces ciliary elongation and increased intensity of acetylated α-tubulin labeling in the cells and is phosphorylated by Mak. These results suggest that Mak is essential for the regulation of ciliary length and is required for the long-term survival of photoreceptors.

  1. Zygote arrest 1 gene in pig, cattle and human: evidence of different transcript variants in male and female germ cells

    Directory of Open Access Journals (Sweden)

    Royere Dominique

    2006-03-01

    development highlighted by expression pattern of full-length transcript in oocytes and early embryos, ZAR1 could also be implicated in the regulation of meiosis and post meiotic differentiation of male and female germ cells through expression of shorter splicing variants. Species conservation of ZAR1 expression and regulation underlines the central role of this gene in early reproductive processes.

  2. Uptake and dosimetry of Auger emitting diagnostic radionuclides (in particular indium-111) in human male germ cells

    International Nuclear Information System (INIS)

    Nettleton, J.S.; Lawson, R.S.; Prescott, M.C.; Hoyes, K.P.; Morris, I.D.

    2000-01-01

    a factor of 3, whereas those for 201 Tl might be too high by a factor of 4. No data was obtained for uptake by differing germ cell types within the testis and therefore no consideration of dosimetry at the cellular level was possible. It was concluded that uptake of diagnostic Auger emitting radionuclides by male germ cells (and especially sperm) is possible following intravenous administration. In the case of 111 In at least, the resulting cellular radiation dose, calculated to include the contributions of Auger electrons, might be large enough to cause DNA damage with significant biological consequences. (author)

  3. Zygote arrest 1 gene in pig, cattle and human: evidence of different transcript variants in male and female germ cells

    Science.gov (United States)

    Uzbekova, Svetlana; Roy-Sabau, Monica; Dalbiès-Tran, Rozenn; Perreau, Christine; Papillier, Pascal; Mompart, Florence; Thelie, Aurore; Pennetier, Sophie; Cognie, Juliette; Cadoret, Veronique; Royere, Dominique; Monget, Philippe; Mermillod, Pascal

    2006-01-01

    expression pattern of full-length transcript in oocytes and early embryos, ZAR1 could also be implicated in the regulation of meiosis and post meiotic differentiation of male and female germ cells through expression of shorter splicing variants. Species conservation of ZAR1 expression and regulation underlines the central role of this gene in early reproductive processes. PMID:16551357

  4. Development of the adverse outcome pathway "alkylation of DNA in male premeiotic germ cells leading to heritable mutations" using the OECD's users' handbook supplement.

    Science.gov (United States)

    Yauk, Carole L; Lambert, Iain B; Meek, M E Bette; Douglas, George R; Marchetti, Francesco

    2015-12-01

    The Organisation for Economic Cooperation and Development's (OECD) Adverse Outcome Pathway (AOP) programme aims to develop a knowledgebase of all known pathways of toxicity that lead to adverse effects in humans and ecosystems. A Users' Handbook was recently released to provide supplementary guidance on AOP development. This article describes one AOP-alkylation of DNA in male premeiotic germ cells leading to heritable mutations. This outcome is an important regulatory endpoint. The AOP describes the biological plausibility and empirical evidence supporting that compounds capable of alkylating DNA cause germ cell mutations and subsequent mutations in the offspring of exposed males. Alkyl adducts are subject to DNA repair; however, at high doses the repair machinery becomes saturated. Lack of repair leads to replication of alkylated DNA and ensuing mutations in male premeiotic germ cells. Mutations that do not impair spermatogenesis persist and eventually are present in mature sperm. Thus, the mutations are transmitted to the offspring. Although there are some gaps in empirical support and evidence for essentiality of the key events for certain aspects of this AOP, the overall AOP is generally accepted as dogma and applies broadly to any species that produces sperm. The AOP was developed and used in an iterative process to test and refine the Users' Handbook, and is one of the first publicly available AOPs. It is our hope that this AOP will be leveraged to develop other AOPs in this field to advance method development, computational models to predict germ cell effects, and integrated testing strategies. © 2015 Her Majesty the Queen in Right of Canada.

  5. Study on the regulatory mechanism of the lipid metabolism pathways during chicken male germ cell differentiation based on RNA-seq.

    Science.gov (United States)

    Zuo, Qisheng; Li, Dong; Zhang, Lei; Elsayed, Ahmed Kamel; Lian, Chao; Shi, Qingqing; Zhang, Zhentao; Zhu, Rui; Wang, Yinjie; Jin, Kai; Zhang, Yani; Li, Bichun

    2015-01-01

    Here, we explore the regulatory mechanism of lipid metabolic signaling pathways and related genes during differentiation of male germ cells in chickens, with the hope that better understanding of these pathways may improve in vitro induction. Fluorescence-activated cell sorting was used to obtain highly purified cultures of embryonic stem cells (ESCs), primitive germ cells (PGCs), and spermatogonial stem cells (SSCs). The total RNA was then extracted from each type of cell. High-throughput analysis methods (RNA-seq) were used to sequence the transcriptome of these cells. Gene Ontology (GO) analysis and the KEGG database were used to identify lipid metabolism pathways and related genes. Retinoic acid (RA), the end-product of the retinol metabolism pathway, induced in vitro differentiation of ESC into male germ cells. Quantitative real-time PCR (qRT-PCR) was used to detect changes in the expression of the genes involved in the retinol metabolic pathways. From the results of RNA-seq and the database analyses, we concluded that there are 328 genes in 27 lipid metabolic pathways continuously involved in lipid metabolism during the differentiation of ESC into SSC in vivo, including retinol metabolism. Alcohol dehydrogenase 5 (ADH5) and aldehyde dehydrogenase 1 family member A1 (ALDH1A1) are involved in RA synthesis in the cell. ADH5 was specifically expressed in PGC in our experiments and aldehyde dehydrogenase 1 family member A1 (ALDH1A1) persistently increased throughout development. CYP26b1, a member of the cytochrome P450 superfamily, is involved in the degradation of RA. Expression of CYP26b1, in contrast, decreased throughout development. Exogenous RA in the culture medium induced differentiation of ESC to SSC-like cells. The expression patterns of ADH5, ALDH1A1, and CYP26b1 were consistent with RNA-seq results. We conclude that the retinol metabolism pathway plays an important role in the process of chicken male germ cell differentiation.

  6. Human iPS Cell-Derived Germ Cells: Current Status and Clinical Potential

    Directory of Open Access Journals (Sweden)

    Tetsuya Ishii

    2014-10-01

    Full Text Available Recently, fertile spermatozoa and oocytes were generated from mouse induced pluripotent (iPS cells using a combined in vitro and in vivo induction system. With regard to germ cell induction from human iPS cells, progress has been made particularly in the male germline, demonstrating in vitro generation of haploid, round spermatids. Although iPS-derived germ cells are expected to be developed to yield a form of assisted reproductive technology (ART that can address unmet reproductive needs, genetic and/or epigenetic instabilities abound in iPS cell generation and germ cell induction. In addition, there is still room to improve the induction protocol in the female germline. However, rapid advances in stem cell research are likely to make such obstacles surmountable, potentially translating induced germ cells into the clinical setting in the immediate future. This review examines the current status of the induction of germ cells from human iPS cells and discusses the clinical potential, as well as future directions.

  7. AZFa protein DDX3Y is differentially expressed in human male germ cells during development and in testicular tumours

    DEFF Research Database (Denmark)

    Gueler, B; Sonne, S B; Zimmer, J

    2012-01-01

    are believed to originate from fetal gonocytes.METHODSDDX3Y protein expression was analysed during development in different tissues by western blotting. The localization of DDX3Y in normal fetal and prepubertal testis tissue of different ages as well as in a series of distinct TGCT tissue samples (CIS......, classical seminoma, spermatocytic seminoma, teratoma and embryonal carcinoma) was performed by immunohistochemistry.RESULTSGerm cell-specific expression of DDX3Y protein was revealed in fetal prospermatogonia but not in gonocytes and not before the 17th gestational week. After birth, DDX3Y was expressed......, but not in somatically differentiated non-seminomas, consistent with its germ-cell specific function.CONCLUSIONSThe fetal germ cell DDX3Y expression suggests a role in early spermatogonial proliferation and implies that, in men with AZFa deletion, germ cell depletion may begin prenatally. The strong expression of DDX3Y...

  8. Dead end1 is an essential partner of NANOS2 for selective binding of target RNAs in male germ cell development.

    Science.gov (United States)

    Suzuki, Atsushi; Niimi, Yuki; Shinmyozu, Kaori; Zhou, Zhi; Kiso, Makoto; Saga, Yumiko

    2016-01-01

    RNA-binding proteins (RBPs) play important roles for generating various cell types in many developmental processes, including eggs and sperms. Nanos is widely known as an evolutionarily conserved RNA-binding protein implicated in germ cell development. Mouse NANOS2 interacts directly with the CCR4-NOT (CNOT) deadenylase complex, resulting in the suppression of specific RNAs. However, the mechanisms involved in target specificity remain elusive. We show that another RBP, Dead end1 (DND1), directly interacts with NANOS2 to load unique RNAs into the CNOT complex. This interaction is mediated by the zinc finger domain of NANOS2, which is essential for its association with target RNAs. In addition, the conditional deletion of DND1 causes the disruption of male germ cell differentiation similar to that observed in Nanos2-KO mice. Thus, DND1 is an essential partner for NANOS2 that leads to the degradation of specific RNAs. We also present the first evidence that the zinc finger domain of Nanos acts as a protein-interacting domain for another RBP, providing a novel insight into Nanos-mediated germ cell development. © 2015 The Authors.

  9. Interaction between NANOS2 and the CCR4-NOT Deadenylation Complex Is Essential for Male Germ Cell Development in Mouse

    OpenAIRE

    Suzuki, Atsushi; Saba, Rie; Miyoshi, Kei; Morita, Yoshinori; Saga, Yumiko

    2012-01-01

    Nanos is one of the evolutionarily conserved proteins implicated in germ cell development and we have previously shown that it interacts with the CCR4-NOT deadenylation complex leading to the suppression of specific RNAs. However, the molecular mechanism and physiological significance of this interaction have remained elusive. In our present study, we identify CNOT1, a component of the CCR4-NOT deadenylation complex, as a direct factor mediating the interaction with NANOS2. We find that the f...

  10. Contribution of environmental pollutants to male infertily: A working model of germ cell apoptosis induced by plasticizers

    Directory of Open Access Journals (Sweden)

    Raúl Lagos-Cabré

    2012-01-01

    Full Text Available Bisphenol A [2,2-bis(4-hydroxyphenylpropane] (BPA, 4-nonylphenol (NP and di(2-ethylhexylphthalate (DEHP, and its metabolite mono-2-ethylhexyl phthalate (MEHP are chemicals found in plastics, which act as endocrine disruptors (EDs in animals, including human. EDs act like hormones in the endocrine system, and disrupt the physiologic function of endogenous hormones. Most people are exposed to different endocrine disruptors and concern has been raised about their true effect on reproductive organs. In the testis, they seem to preferentially attack developing testis during puberty rather than adult organs. However, the lack of information about the molecular mechanism, and the apparently controversial effect observed in different models has hampered the understanding of their effects on mammalian spermatogenesis. In this review, we critically discuss the available information regarding the effect of BPA, NP and DEHP/ MEHP upon mammalian spermatogenesis, a major target of EDs. Germ cell sloughing, disruption of the blood-testis-barrier and germ cell apoptosis are the most common effects reported in the available literature. We propose a model at the molecular level to explain the effects at the cellular level, mainly focused on germ cell apoptosis.

  11. In Vitro Modeling of Human Germ Cell Development Using Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Yuncheng Zhao

    2018-02-01

    Full Text Available Summary: Due to differences across species, the mechanisms of cell fate decisions determined in mice cannot be readily extrapolated to humans. In this study, we developed a feeder- and xeno-free culture protocol that efficiently induced human pluripotent stem cells (iPSCs into PLZF+/GPR125+/CD90+ spermatogonium-like cells (SLCs. These SLCs were enriched with key genes in germ cell development such as MVH, DAZL, GFRα1, NANOS3, and DMRT1. In addition, a small fraction of SLCs went through meiosis in vitro to develop into haploid cells. We further demonstrated that this chemically defined induction protocol faithfully recapitulated the features of compromised germ cell development of PSCs with NANOS3 deficiency or iPSC lines established from patients with non-obstructive azoospermia. Taken together, we established a powerful experimental platform to investigate human germ cell development and pathology related to male infertility. : In this article, Wang and colleagues established a feeder- and xeno-free system to robustly induce human pluripotent stem cells (PSCs into spermatogonia-like cells. This chemically defined induction protocol faithfully recapitulated the features of compromised germ cell development of PSCs with NANOS3 deficiency or iPSC lines established from patients with non-obstructive azoospermia. Keywords: pluripotent stem cells, spermatogonia, infertility, non-obstructive azoospermia

  12. Production of haploids and doubled haploids in oil palm

    Directory of Open Access Journals (Sweden)

    Croxford Adam E

    2010-10-01

    Full Text Available Abstract Background Oil palm is the world's most productive oil-food crop despite yielding well below its theoretical maximum. This maximum could be approached with the introduction of elite F1 varieties. The development of such elite lines has thus far been prevented by difficulties in generating homozygous parental types for F1 generation. Results Here we present the first high-throughput screen to identify spontaneously-formed haploid (H and doubled haploid (DH palms. We secured over 1,000 Hs and one DH from genetically diverse material and derived further DH/mixoploid palms from Hs using colchicine. We demonstrated viability of pollen from H plants and expect to generate 100% homogeneous F1 seed from intercrosses between DH/mixoploids once they develop female inflorescences. Conclusions This study has generated genetically diverse H/DH palms from which parental clones can be selected in sufficient numbers to enable the commercial-scale breeding of F1 varieties. The anticipated step increase in productivity may help to relieve pressure to extend palm cultivation, and limit further expansion into biodiverse rainforest.

  13. Male and female rat bone marrow-derived mesenchymal stem cells are different in terms of the expression of germ cell specific genes.

    Science.gov (United States)

    Ghasemzadeh-Hasankolaei, Mohammad; Eslaminejad, Mohammadreza Baghaban; Batavani, Roozali; Ghasemzadeh-Hasankolaei, Maryam

    2015-06-01

    Recent studies have shown that mesenchymal stem cells (MSCs), under appropriate conditions, can differentiate into cell types including germ cells (GCs). These studies also show that MSCs without any induction express some GC-specific genes innately. Moreover, one report suggests that female MSCs have a greater tendency to differentiate into female instead of male GCs. Therefore, for the first time, this study attempts to assay and determine the differences between the expression levels of some important GC-specific genes (Stra8, Vasa, Dazl, Stella, Piwil2, Oct4, Fragilis, Rnf17 and c-Kit) in male and female bone marrow (BM)-MSCs of rats. BM sampling of the rate was performed by a newly established method. We cultured rat BM samples, then characterized male and female MSCs according to their adhesion onto the culture dish, their differentiation potential into bone, cartilage and fat cells, and phenotype analysis by flow cytometry. The expression of GC-specific genes and their expression levels were evaluated with reverse transcription polymerase chain reaction (RT-PCR) and real-time RT-PCR. Our results showed that Dazl and Rnf17 did not express in the cells. The majority of examined genes, except Piwil2, expressed at almost the same levels in male and female MSCs. Piwil2 had higher expression in male MSCs which was probably related to the more prominent role of Piwil2 in the male GC development process. Male BM-MSCs appeared more prone to differentiate into male rather than female GCs. Additional research should be performed to determine the exact role of different genes in the male and female GC development process.

  14. The Potent Humanin Analogue (HNG) Protects Germ Cells and Leucocytes While Enhancing Chemotherapy-Induced Suppression of Cancer Metastases in Male Mice.

    Science.gov (United States)

    Lue, YanHe; Swerdloff, Ronald; Wan, Junxiang; Xiao, Jialin; French, Samuel; Atienza, Vince; Canela, Victor; Bruhn, Kevin W; Stone, Brian; Jia, Yue; Cohen, Pinchas; Wang, Christina

    2015-12-01

    Humanin is a peptide that is cytoprotective against stresses in many cell types. We investigated whether a potent humanin analogue S14G-humanin (HNG) would protect against chemotherapy-induced damage to normal cells without interfering with the chemotherapy-induced suppression of cancer cells. Young adult male mice were inoculated iv with murine melanoma cells. After 1 week, cancer-bearing mice were randomized to receive either: no treatment, daily ip injection of HNG, a single ip injection of cyclophosphamide (CP), or CP+HNG and killed at the end of 3 weeks. HNG rescued the CP-induced suppression of leucocytes and protected germ cell from CP-induced apoptosis. Lung metastases were suppressed by HNG or CP alone, and further suppressed by CP+HNG treatment. Plasma IGF-1 levels were suppressed by HNG with or without CP treatment. To investigate whether HNG maintains its protective effects on spermatogonial stem cells, sperm output, and peripheral leucocytes after repeated doses of CP, normal adult male mice received: no treatment, daily sc injection of HNG, 6 ip injections of CP at 5-day intervals, and the same regimens of CP+HNG and killed at the end of 4 weeks of treatment. Cauda epididymal sperm counts were elevated by HNG and suppressed by CP. HNG rescued the CP-induced suppression of spermatogonial stem cells, sperm count and peripheral leucocytes. We conclude that HNG 1) protects CP-induced loss of male germ cells and leucocytes, 2) enhances CP-induced suppression of cancer metastases, and 3) acts as a caloric-restriction mimetic by suppressing IGF-1 levels. Our findings suggest that humanin analogues may be promising adjuvants to chemotherapy.

  15. SEPT12/SPAG4/LAMINB1 complexes are required for maintaining the integrity of the nuclear envelope in postmeiotic male germ cells.

    Science.gov (United States)

    Yeh, Chung-Hsin; Kuo, Pao-Lin; Wang, Ya-Yun; Wu, Ying-Yu; Chen, Mei-Feng; Lin, Ding-Yen; Lai, Tsung-Hsuan; Chiang, Han-Sun; Lin, Ying-Hung

    2015-01-01

    Male infertility affects approximately 50% of all infertile couples. The male-related causes of intracytoplasmic sperm injection failure include the absence of sperm, immotile or immature sperm, and sperm with structural defects such as those caused by premature chromosomal condensation and DNA damage. Our previous studies based on a knockout mice model indicated that SEPT12 proteins are critical for the terminal morphological formation of sperm. SEPT12 mutations in men result in teratozospermia and oligozospermia. In addition, the spermatozoa exhibit morphological defects of the head and tail, premature chromosomal condensation, and nuclear damage. However, the molecular functions of SEPT12 during spermatogenesis remain unclear. To determine the molecular functions of SEPT12, we applied a yeast 2-hybrid system to identify SEPT12 interactors. Seven proteins that interact with SEPT12 were identified: SEPT family proteins (SEPT4 and SEPT6), nuclear or nuclear membrane proteins (protamine 2, sperm-associated antigen 4, and NDC1 transmembrane nucleoproine), and sperm-related structural proteins (pericentriolar material 1 and obscurin-like 1). Sperm-associated antigen 4 (SPAG4; also known as SUN4) belongs to the SUN family of proteins and acts as a linker protein between nucleoskeleton and cytoskeleton proteins and localizes in the nuclear membrane. We determined that SEPT12 interacts with SPAG4 in a male germ cell line through coimmunoprecipitation. During human spermiogenesis, SEPT12 is colocalized with SPAG4 near the nuclear periphery in round spermatids and in the centrosome region in elongating spermatids. Furthermore, we observed that SEPT12/SPAG4/LAMINB1 formed complexes and were coexpressed in the nuclear periphery of round spermatids. In addition, mutated SEPT12, which was screened from an infertile man, affected the integration of these nuclear envelope complexes through coimmunoprecipitation. This was the first study that suggested that SEPT proteins link to

  16. SEPT12/SPAG4/LAMINB1 complexes are required for maintaining the integrity of the nuclear envelope in postmeiotic male germ cells.

    Directory of Open Access Journals (Sweden)

    Chung-Hsin Yeh

    Full Text Available Male infertility affects approximately 50% of all infertile couples. The male-related causes of intracytoplasmic sperm injection failure include the absence of sperm, immotile or immature sperm, and sperm with structural defects such as those caused by premature chromosomal condensation and DNA damage. Our previous studies based on a knockout mice model indicated that SEPT12 proteins are critical for the terminal morphological formation of sperm. SEPT12 mutations in men result in teratozospermia and oligozospermia. In addition, the spermatozoa exhibit morphological defects of the head and tail, premature chromosomal condensation, and nuclear damage. However, the molecular functions of SEPT12 during spermatogenesis remain unclear. To determine the molecular functions of SEPT12, we applied a yeast 2-hybrid system to identify SEPT12 interactors. Seven proteins that interact with SEPT12 were identified: SEPT family proteins (SEPT4 and SEPT6, nuclear or nuclear membrane proteins (protamine 2, sperm-associated antigen 4, and NDC1 transmembrane nucleoproine, and sperm-related structural proteins (pericentriolar material 1 and obscurin-like 1. Sperm-associated antigen 4 (SPAG4; also known as SUN4 belongs to the SUN family of proteins and acts as a linker protein between nucleoskeleton and cytoskeleton proteins and localizes in the nuclear membrane. We determined that SEPT12 interacts with SPAG4 in a male germ cell line through coimmunoprecipitation. During human spermiogenesis, SEPT12 is colocalized with SPAG4 near the nuclear periphery in round spermatids and in the centrosome region in elongating spermatids. Furthermore, we observed that SEPT12/SPAG4/LAMINB1 formed complexes and were coexpressed in the nuclear periphery of round spermatids. In addition, mutated SEPT12, which was screened from an infertile man, affected the integration of these nuclear envelope complexes through coimmunoprecipitation. This was the first study that suggested that SEPT

  17. Secondary nocturnal enuresis related to central diabetes insipidus as an early manifestation of intracranial germinomatous germ cell tumors in a series of male youngsters.

    Science.gov (United States)

    Papaefthimiou, Apostolos; Kyrgios, Ioannis; Kotanidou, Eleni P; Maggana, Ioanna; Mouzaki, Konstantina; Galli-Tsinopoulou, Assimina

    2015-02-01

    Nocturnal enuresis is a common symptom in children. It is usually attributed to benign causes and diagnostic evaluation is not carried out. We report three male young patients initially presenting with short stature and nocturnal enuresis, related to diabetes insipidus, caused by intracranial germinomatous germ cell tumors. In all three cases, water deprivation tests confirmed diabetes insipidus. Extensive endocrinological investigation also showed further hormone deficiencies. Magnetic resonance imaging of the brain revealed the presence of a central nervous system lesion and histology confirmed the final diagnosis. Surgery, radiation with or without chemotherapy was conducted and the patients were treated with hormone replacement therapies. The patients after a long follow-up were free of disease. We present these cases to alert clinicians to bear in mind that the presence of an intracranial germinomatous germ cell tumor should at least be considered in a child presenting with bed wetting, especially if additional symptoms and signs, including late onset puberty and growth delay or morning hypernatremia, may coexist. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  18. Interaction between NANOS2 and the CCR4-NOT deadenylation complex is essential for male germ cell development in mouse.

    Directory of Open Access Journals (Sweden)

    Atsushi Suzuki

    Full Text Available Nanos is one of the evolutionarily conserved proteins implicated in germ cell development and we have previously shown that it interacts with the CCR4-NOT deadenylation complex leading to the suppression of specific RNAs. However, the molecular mechanism and physiological significance of this interaction have remained elusive. In our present study, we identify CNOT1, a component of the CCR4-NOT deadenylation complex, as a direct factor mediating the interaction with NANOS2. We find that the first 10 amino acids (AAs of NANOS2 are required for this binding. We further observe that a NANOS2 mutant lacking these first 10 AAs (NANOS2-ΔN10 fails to rescue defects in the Nanos2-null mouse. Our current data thus indicate that the interaction with the CCR4-NOT deadenylation complex is essential for NANOS2 function. In addition, we further demonstrate that NANOS2-ΔN10 can associate with specific mRNAs as well as wild-type NANOS2, suggesting the existence of other NANOS2-associated factor(s that determine the specificity of RNA-binding independently of the CCR4-NOT deadenylation complex.

  19. Generation of Mouse Haploid Somatic Cells by Small Molecules for Genome-wide Genetic Screening

    Directory of Open Access Journals (Sweden)

    Zheng-Quan He

    2017-08-01

    Full Text Available The recent success of derivation of mammalian haploid embryonic stem cells (haESCs has provided a powerful tool for large-scale functional analysis of the mammalian genome. However, haESCs rapidly become diploidized after differentiation, posing challenges for genetic analysis. Here, we show that the spontaneous diploidization of haESCs happens in metaphase due to mitotic slippage. Diploidization can be suppressed by small-molecule-mediated inhibition of CDK1 and ROCK. Through ROCK inhibition, we can generate haploid somatic cells of all three germ layers from haESCs, including terminally differentiated neurons. Using piggyBac transposon-based insertional mutagenesis, we generated a haploid neural cell library harboring genome-wide mutations for genetic screening. As a proof of concept, we screened for Mn2+-mediated toxicity and identified the Park2 gene. Our findings expand the applications of mouse haploid cell technology to somatic cell types and may also shed light on the mechanisms of ploidy maintenance.

  20. Studies on chromosomal aberrations and dominant lethal mutations induced by x irradiation in germ cells of male mice

    International Nuclear Information System (INIS)

    Wang Xianli; Wang Mingdong; Wang Bin; Sun Shuqing

    1992-01-01

    After male mice irradiated by 2 Gy X rays mated to normal virginal females superovulated with PMSG and HCG, pronuclei chromosome spreading of first-cleavage embryos were prepared and chromosomal aberrations of paternal pronuclei were observed. The results showed that the frequency of chromosomal aberrations was highest irradiated at spermatic stage among different stages of spermatogenesis. The sequence of radiosensitivity in spermatogenesis was as follows: spermatids > mature sperm > spermatocyte > spermatogonia and stem spermatogonia. The frequencies of paternal chromosomal aberrations resulted from irradiation at spermatids and mature sperms were significantly higher than that in control. The reciprocal translocations of stem spermatogonia induced by 2 Gy X rays in those male mice were also examined in the preparations of diakinesis-metaphase I. The frequency of reciprocal translocations were 0.0429 per cell and significantly higher than that in control. The proportion of unbalanced gametes, resulting in lethal embryos after fertilization, was 0.02145 to be predicted. At the same time, the dominant lethality induced by X rays in stem spermatogonia was measured, being 0.0371. The frequency of dead fetuses in irradiation group was about twice as in control. The regression analysis was found that the reciprocal translocations was markedly related to the dominant lethality

  1. Cytoplasmic protein binding to highly conserved sequences in the 3' untranslated region of mouse protamine 2 mRNA, a translationally regulated transcript of male germ cells

    International Nuclear Information System (INIS)

    Kwon, Y.K.; Hecht, N.B.

    1991-01-01

    The expression of the protamines, the predominant nuclear proteins of mammalian spermatozoa, is regulated translationally during male germ-cell development. The 3' untranslated region (UTR) of protamine 1 mRNA has been reported to control its time of translation. To understand the mechanisms controlling translation of the protamine mRNAs, we have sought to identify cis elements of the 3' UTR of protamine 2 mRNA that are recognized by cytoplasmic factors. From gel retardation assays, two sequence elements are shown to form specific RNA-protein complexes. Protein binding sites of the two complexes were determined by RNase T1 mapping, by blocking the putative binding sites with antisense oligonucleotides, and by competition assays. The sequences of these elements, located between nucleotides + 537 and + 572 in protamine 2 mRNA, are highly conserved among postmeiotic translationally regulated nuclear proteins of the mammalian testis. Two closely linked protein binding sites were detected. UV-crosslinking studies revealed that a protein of about 18 kDa binds to one of the conserved sequences. These data demonstrate specific protein binding to a highly conserved 3' UTR of translationally regulated testicular mRNA

  2. Local cluster of germ cell cancer in a cohort of male automotive workers in Germany not explained by previous or concurrent activities and exposures in farming and forestry.

    Science.gov (United States)

    Schmeisser, N; Behrens, T; Mester, B; Gottlieb, A; Langner, I; Ahrens, W

    2011-02-01

    To examine whether exposures or activities in farming, forestry and related occupations explain the excess incidence of germ cell cancer (GCC) observed among male employees in one of the six car-manufacturing plants that is located in a geographic area where farming is frequent. A cohort based case-control study was conducted among workers in six car-manufacturing plants located in areas with different industrial structure. The study involved 188 cases of germ cell cancer identified through active retrieval in 38 hospitals and 1000 controls, drawn from administrative accounting files, individually matched by year of birth (± 2 years). Information regarding tasks and exposures and potential confounding variables were obtained by face-to-face or telephone interviews. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using a conditional logistic regression model adjusted for cryptorchidism and other potential confounders. In this case-control study 5.3% of cases and 6.3% of controls ever worked in agriculture or livestock farming. No increased risks were observed for working in agriculture (OR=0.8 95% CI: 0.4-1.6), livestock farming (OR=0.8 95% CI: 0.4-1.6) or for exposure to pesticides (OR=0.7 95% CI: 0.3-1.7), for exposure to fertilizers (OR=0.8 95% CI: 0.4-1.8) and disinfectants (OR=1.0 95% CI: 0.3-2.8). There were no statistically significant increases in risk associated with ever exposure to salt based wood protection agents (OR=2.3 95% CI: 0.6-9.1), working with plywood (OR=1.4 95% CI: 0.6-3.2), coated wood (OR=1.4 95% CI: 0.5-3.9) or working in forestry (OR=1.7 95% CI: 0.5-6.4). Lagging of exposures did not alter the results. The observed excess incidence in the cohort of automotive workers can be hardly explained by previous or concurrent work in farming or forestry. Because of the small numbers of subjects ever employed in farming the statistical power in assessing associations between agricultural work and agricultural exposures was limited

  3. The influence of large deletions on the mutation frequency induced by tritiated water and X-radiation in male Drosophila melanogaster post-meiotic germ cells

    International Nuclear Information System (INIS)

    Fossett, N.G.; Byrne, B.J.; Kelley, S.J.; Tucker, A.B.; Arbour-Reily, P.; Lee, W.R.

    1994-01-01

    Tritium beta radiation ( 3 H β-radiation) in the form of tritiated water was used to induce mutations at the alcohol dehydrogenase (Adh) locus in male Drosophila melanogaster post-meiotic germ cells. All 23 Adh null mutations were large deletions (>20 kb), determined by genetic complementation and Southern blot analyses. 27 Adh null mutations have been induced by 100-kVp X-rays and have been genetically and molecularly characterized. In contrast to 3 H β-radiation, 100-kVp X-rays induced a bimodal distribution of Adh null mutations, intragenic mutations, ≤250 bp, and large deletions, >100 kb. A statistically significant difference was observed between the frequency of large deletions (23/23 or 1.0) induced by 3 H β-radiation and the frequency of large deletions (19/27 or 0.7) induced by 100-kVp X-rays. However, a statistical difference was not observed between the size distribution of the large deletions induced by 3 H β-radiation and X-rays. The relative deletion frequency (RDF) induced by 3 H β-radiation and 100-kVp X-rays was (1.0/0.7=1.4). The relative biological effectiveness (RBE) of these two radiation sources was 1.4, determined from the ratio of the regression coefficients of the respective 3 H β-radiation and X-ray sex-linked recessive lethal (SLRL) dose-response data. The large difference in size between the two classes of X-ray-induced Adh null mutations and the increase in mutation frequency and deletion frequency for 3 H β-radiation with respect to X-rays may indicate that the relative deletion frequency (RDF) is the molecular biological basis for the increase in the RBE for radiation sources with a mean LET value ≤10 keV/μm

  4. CRISPR/Cas9-Mediated Deletion of C1EIS Inhibits Chicken Embryonic Stem Cell Differentiation Into Male Germ Cells (Gallus gallus).

    Science.gov (United States)

    Zuo, Qisheng; Jin, Kai; Wang, Yingjie; Song, Jiuzhou; Zhang, Yani; Li, Bichun

    2017-08-01

    We previously found that C1EIS is preferentially expressed in Chicken spermatogonial stem cells (SSCs) by RNA sequencing (RNA-seq), so our current study focused on C1EIS's role in Chicken embryonic stem cells (ESCs) differentiation into male germ cells. We constructed a CRISPR/Cas9 vector targeting C1EIS. T7 endonuclease I (T7EI) digestion method and sequencing of TA cloning were used to detect the knock-out efficiency of the Single guide RNA (sgRNA) after the cas9/gRNA vector transfected into D fibroblasts 1(DF-1), ESCs, and Chicken embryos. The results showed that CRISPR/Cas9 gene knockout efficiency is about 40%. Differentiation of the targeted ESCs into SSCs was inhibited at the embryoid body stage due to C1EIS deficiency. Immunofluorescent staining revealed that the mutagenized ESCs (RA (Retinoic Acid) with C1EIS Knock out) expressed lower levels of integrin α6 and integrin β1 compared to wild type cells. Quantitative real-time PCR (QRT-PCR) revealed Oct4 and Sox2 expression significantly increased, contrarily integrin β1 and Stra8 expression significantly decreased than RA induced group and RA with C1EIS Overexpression. During retinoic acid-induced differentiation, knockout of C1EIS in ESCs inhibited formation of SSC-like cells, suggesting C1EIS plays a vital role in promoting differentiation of avian ESCs to SSCs by regulating expression of multiple pluripotency-related genes. J. Cell. Biochem. 118: 2380-2386, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  5. Physical mapping of a commonly deleted region, the site of a candidate tumor suppressor gene, at 12q22 in human male germ cell tumors

    Energy Technology Data Exchange (ETDEWEB)

    Murty, V.V.V.S.; Bosl, G.J.; Chaganti, R.S.K. [Memorial Sloan-Kettering Cancer Center, New York, NY (United States)] [and others

    1996-08-01

    A candidate tumor suppressor gene (TSG) site at 12q22 characterized by a high frequency of loss of heterozygosity (LOH) and a homozygous deletion has previously (LOH) and a homozygous deletion has previously been reported in human male germ cell tumors (GCTs). In a detailed deletion mapping analysis of 67 normal-tumor DNAs utilizing 20 polymorphic markers mapped to 12q22-q24, we identified the limits of the minimal region of deletion at 12q22 between D12S377 (priximal) and D12S296 (distal). We have constructed a YAC contig map of a 3-cM region of this band between the proximal marker D12S101 and the distal marker D12S346, which contained the minimal region of deletion in GCTs. The map is composed of 53 overlapping YACs and 3 cosmids onto which 25 polymorphic and nonpolymorphic sequence-tagged sites (STSs) were placed in a unique order. The size of the minimal region of deletion was approximately 2 Mb from overlapping, nonchimeric YACs that spanned the region. We also developed a radiation hybrid (RH) map of the region between D12S101 and D12S346 containing 17 loci. The consensus order developed by RH mapping is in good agreement with the YAC STS-content map order. The RH map estimated the distance between D12S101 and D12S346 to be 246 cR{sub 8000} and the minimal region of deletion to be 141 cR{sub 8000}. In addition, four genes that were previously mapped to 12q22 have been excluded as candidate genes. The leads gained from the deletion mapping and physical maps should expedite the isolation and characterization of the TSG at 12q22. 35 refs., 4 figs., 2 tabs.

  6. Genetic control of the development of the haploid generation in Oenothera

    Directory of Open Access Journals (Sweden)

    Cornelia Harte

    2014-01-01

    Full Text Available The haploid generation of higher plants has to be considered in its own individuality. Special experimental designs are needed to investigate the developmental processes of the male and female gametophytes between meiosis and fertilization. Experiments on Oenothera demonstrate the existence of genes, which action can be described as influencing the competition between meiospores or between gametophytes, or as interaction between different individuals, the gametophytic-gametophytic and gametophytic-sporophytic incompatibility. The development of the haploid generation is regulated by genes. Some of these genes are active only in this phase of the life cycle.

  7. The evolution of sex chromosomes in organisms with separate haploid sexes.

    Science.gov (United States)

    Immler, Simone; Otto, Sarah Perin

    2015-03-01

    The evolution of dimorphic sex chromosomes is driven largely by the evolution of reduced recombination and the subsequent accumulation of deleterious mutations. Although these processes are increasingly well understood in diploid organisms, the evolution of dimorphic sex chromosomes in haploid organisms (U/V) has been virtually unstudied theoretically. We analyze a model to investigate the evolution of linkage between fitness loci and the sex-determining region in U/V species. In a second step, we test how prone nonrecombining regions are to degeneration due to accumulation of deleterious mutations. Our modeling predicts that the decay of recombination on the sex chromosomes and the addition of strata via fusions will be just as much a part of the evolution of haploid sex chromosomes as in diploid sex chromosome systems. Reduced recombination is broadly favored, as long as there is some fitness difference between haploid males and females. The degeneration of the sex-determining region due to the accumulation of deleterious mutations is expected to be slower in haploid organisms because of the absence of masking. Nevertheless, balancing selection often drives greater differentiation between the U/V sex chromosomes than in X/Y and Z/W systems. We summarize empirical evidence for haploid sex chromosome evolution and discuss our predictions in light of these findings. © 2015 The Author(s).

  8. Use of intergeneric cross for production of doubled haploid wheat (triticum aestivum l.)

    International Nuclear Information System (INIS)

    Khan, M.A.; Shaukat, S.; Kashif, M.; Khan, A.S.

    2012-01-01

    The main purpose of conventional breeding or hybridisation is to bring about homozygosity, for which 6 to 7 years may be required. Wheat and maize crosses have proved to be more efficient in DH lines production than anther culture methods, because of its lower genetic specificity. Doubled haploid technique facilitates the development of homozygous plants within one generation. The system is developed through haploid production, followed by chromosome doubling, to produce homozygous plants in a single generation. For doubled haploid production method wheat and maize crossing system is better than anther culture and ovule culture because maize pollens are highly responsive and produce stable progeny population. Wheat is being used as female parent and maize as a male parent for the production of doubled haploid. Moreover, Silver Nitrate (AgNO/sub 3/) in tiller culture media can improve the frequency of haploid embryo production in this crossing system. Our result showed that DH production through wheat and maize crossing system was proved to be time saving (2 years) as compared to other conventional breeding methods (6 years). (author)

  9. Lin28a regulates germ cell pool size and fertility

    Science.gov (United States)

    Shinoda, Gen; de Soysa, T. Yvanka; Seligson, Marc T.; Yabuuchi, Akiko; Fujiwara, Yuko; Huang, Pei Yi; Hagan, John P.; Gregory, Richard I.; Moss, Eric G.; Daley, George Q.

    2013-01-01

    Overexpression of LIN28A is associated with human germ cell tumors and promotes primordial germ cell (PGC) development from embryonic stem cells in vitro and in chimeric mice. Knockdown of Lin28a inhibits PGC development in vitro, but how constitutional Lin28a deficiency affects the mammalian reproductive system in vivo remains unknown. Here, we generated Lin28a knockout (KO) mice and found that Lin28a deficiency compromises the size of the germ cell pool in both males and females by affecting PGC proliferation during embryogenesis. Interestingly however, in Lin28a KO males the germ cell pool partially recovers during postnatal expansion, while fertility remains impaired in both males and females mated to wild type mice. Embryonic overexpression of let-7, a microRNA negatively regulated by Lin28a, reduces the germ cell pool, corroborating the role of the Lin28a/let-7 axis in regulating the germ lineage. PMID:23378032

  10. Characters that differ between diploid and haploid honey bee (Apis mellifera) drones.

    Science.gov (United States)

    Herrmann, Matthias; Trenzcek, Tina; Fahrenhorst, Hartmut; Engels, Wolf

    2005-12-30

    Diploid males have long been considered a curiosity contradictory to the haplo-diploid mode of sex determination in the Hymenoptera. In Apis mellifera, 'false' diploid male larvae are eliminated by worker cannibalism immediately after hatching. A 'cannibalism substance' produced by diploid drone larvae to induce worker-assisted suicide has been hypothesized, but it has never been detected. Diploid drones are only removed some hours after hatching. Older larvae are evidently not regarded as 'false males' and instead are regularly nursed by the brood-attending worker bees. As the pheromonal cues presumably are located on the surface of newly hatched bee larvae, we extracted the cuticular secretions and analyzed their chemical composition by gas chromatograph-mass spectrometry (GC-MS) analyses. Larvae were sexed and then reared in vitro for up to three days. The GC-MS pattern that was obtained, with alkanes as the major compounds, was compared between diploid and haploid drone larvae. We also examined some physical parameters of adult drones. There was no difference between diploid and haploid males in their weight at the day of emergence. The diploid adult drones had fewer wing hooks and smaller testes. The sperm DNA content was 0.30 and 0.15 pg per nucleus, giving an exact 2:1 ratio for the gametocytes of diploid and haploid drones, respectively. Vitellogenin was found in the hemolymph of both types of imaginal drones at 5 to 6 days, with a significantly lower titer in the diploids.

  11. Sequelae in male rabbits following developmental exposure to p,p'-DDT or a mixture of p,p'-DDT and vinclozolin: cryptorchidism, germ cell atypia, and sexual dysfunction.

    Science.gov (United States)

    Veeramachaneni, D N R; Palmer, J S; Amann, R P; Pau, K-Y F

    2007-01-01

    Rabbit does (7-9 per group) were treated daily per orum from gestation day 15 through post-natal week 4 to provide per kg body wt 25 micaromol (low) or 250 micromol (high) p,p'-DDT or a mixture of DDT and vinclozolin (12.5 and 125 micromol each). Developmental as well as post-pubertal reproductive sequelae of male progeny were studied. Testicular descent in some pups was impaired by DDT. Serum LH or testosterone was not affected. FSH was lower in mixture- but not in DDT-exposed rabbits. Lack of sexual interest, penile erection and ejaculation were observed in some mixture rabbits. Sperm counts were unaffected, but morphologically normal spermatozoa were fewer; nuclear and acrosomal morphogenesis was disrupted. Atypical germ cells resembling carcinoma in situ were found. Also considering data for vinclozolin [Veeramachaneni DNR, Palmer JS, Amann RP, Kane CM, Higuchi TT, Pau K-YF. Disruption of sexual function, FSH secretion, and spermiogenesis in rabbits following developmental exposure to vinclozolin, a fungicide. Reproduction 2006;131:805-16], we concluded that DDT causes cryptorchidism and germ cell atypia, vinclozolin permanently disrupts FSH secretion and sexual function, and the mixture causes the full spectrum of dysgenesis.

  12. Discrimination of haploid and diploid maize kernels via multispectral imaging

    DEFF Research Database (Denmark)

    De La Fuente, Gerald N.; Carstensen, Jens Michael; Adsetts Edberg Hansen, Michael

    2017-01-01

    sorting of haploids would increase the efficiency of DH line development. In this study, six inbred lines were crossed with the maternal haploid inducer ‘RWS/RWK-76’ and a sample of seed was sorted manually for each line. Using the VideometerLab 3 system, spectral imaging techniques were applied...

  13. Doubled haploid production in Flax (Linum usitatissimum L.).

    Science.gov (United States)

    Obert, Bohus; Zácková, Zuzana; Samaj, Jozef; Pretová, Anna

    2009-01-01

    There is a requirement of haploid and double haploid material and homozygous lines for cell culture studies and breeding in flax. Anther culture is currently the most successful method producing doubled haploid lines in flax. Recently, ovary culture was also described as a good source of doubled haploids. In this review we focus on tissue and plants regeneration using anther culture, and cultivation of ovaries containing unfertilized ovules. The effect of genotype, physiological status of donor plants, donor material pre-treatment and cultivation conditions for flax anthers and ovaries is discussed here. The process of plant regeneration from anther and ovary derived calli is also in the focus of this review. Attention is paid to the ploidy level of regenerated tissue and to the use of molecular markers for determining of gametic origin of flax plants derived from anther and ovary cultures. Finally, some future prospects on the use of doubled haploids in flax biotechnology are outlined here.

  14. Diploidization of cucumber (Cucumis sativus L. haploids by colchicine treatment

    Directory of Open Access Journals (Sweden)

    Vesselina Nikolova

    2014-01-01

    Full Text Available Haploid cucumber plants are totally infertile and do not undergo spontaneous diploidization. The use of haploids depends on the possibility of doubling the chromosome number and the obtaining of stable doubled haploids (DH. Four haploids of different genotypes propagated vegetatively were treated with colchicine in order to obtain DH. The following procedures were used: 1 apical shoot meristem treatment, 2 soaking of shoot explants, 3 placing of shoot explants on medium with colchicine. Plants of the C1 generation were evaluated in respect to morphological and cytological characters and fertility. The best result of 20.9% DH was obtained after repeated treatment of the meristem with colchicine. A large group of chimeras (28.5% was also distinguished as were haploids and tetraploids. DH plants were fertile and gave uniform progeny. Chimeras had a decreased fertility and showed disturbances in meiotic divisions.

  15. Karyotype and C-banding analyses of haploid male chromosomes ...

    African Journals Online (AJOL)

    Prior to the swarming season, drone-brood cells were added adjoining to the lower rows of the worker-brood cells. Testes from young larvae were removed, fixed in acetic acid methanol (1:3), and stored at -20°C. The slides pretreatment were made by usual air dry method. C-banding and staining was carried out by barium ...

  16. Characterization of in vitro haploid and doubled haploid Chrysanthemum morifolium plants via unfertilized ovule culture for phenotypical traits and DNA methylation pattern.

    Directory of Open Access Journals (Sweden)

    Haibin eWang

    2014-12-01

    Full Text Available Chrysanthemum is one of important ornamental species in the world. Its highly heterozygous state complicates molecular analysis, so it is of interest to derive haploid forms. A total of 2,579 non-fertilized chrysanthemum ovules pollinated by Argyranthemum frutescens were cultured in vitro to isolate haploid progeny. One single regenerant emerged from each of three of the 105 calli produced. Chromosome counts and microsatellite fingerprinting showed that only one of the regenerants was a true haploid. Nine doubled haploid derivatives were subsequently generated by colchicine treatment of 80 in vitro cultured haploid nodal segments. Morphological screening showed that the haploid plant was shorter than the doubled haploids, and developed smaller leaves, flowers and stomata. An in vitro pollen germination test showed that few of the haploid's pollen were able to germinate and those which did so were abnormal. Both the haploid and the doubled haploids produced yellow flowers, whereas those of the maternal parental cultivar were mauve. Methylation-sensitive amplification polymorphism (MSAP profiling was further used to detect alterations in cytosine methylation caused by the haploidization and/or the chromosome doubling processes. While 52.2% of the resulting amplified fragments were cytosine methylated in the maternal parent's genome, the corresponding proportions for the haploid's and doubled haploids' genomes were, respectively, 47.0% and 51.7%, demonstrating a reduction in global cytosine methylation caused by haploidization and a partial recovery following chromosome doubling.

  17. On the development of extragonadal and gonadal human germ cells

    Directory of Open Access Journals (Sweden)

    A. Marijne Heeren

    2016-02-01

    Full Text Available Human germ cells originate in an extragonadal location and have to migrate to colonize the gonadal primordia at around seven weeks of gestation (W7, or five weeks post conception. Many germ cells are lost along the way and should enter apoptosis, but some escape and can give rise to extragonadal germ cell tumors. Due to the common somatic origin of gonads and adrenal cortex, we investigated whether ectopic germ cells were present in the human adrenals. Germ cells expressing DDX4 and/or POU5F1 were present in male and female human adrenals in the first and second trimester. However, in contrast to what has been described in mice, where ‘adrenal’ and ‘ovarian’ germ cells seem to enter meiosis in synchrony, we were unable to observe meiotic entry in human ‘adrenal’ germ cells until W22. By contrast, ‘ovarian’ germ cells at W22 showed a pronounced asynchronous meiotic entry. Interestingly, we observed that immature POU5F1+ germ cells in both first and second trimester ovaries still expressed the neural crest marker TUBB3, reminiscent of their migratory phase. Our findings highlight species-specific differences in early gametogenesis between mice and humans. We report the presence of a population of ectopic germ cells in the human adrenals during development.

  18. [Germ cell membrane lipids in spermatogenesis].

    Science.gov (United States)

    Wang, Ting; Shi, Xiao; Quan, Song

    2016-05-01

    Spermatogenesis is a complex developmental process in which a diploid progenitor germ cell transforms into highly specialized spermatozoa. During spermatogenesis, membrane remodeling takes place, and cell membrane permeability and liquidity undergo phase-specific changes, which are all associated with the alteration of membrane lipids. Lipids are important components of the germ cell membrane, whose volume and ratio fluctuate in different phases of spermatogenesis. Abnormal lipid metabolism can cause spermatogenic dysfunction and consequently male infertility. Germ cell membrane lipids are mainly composed of cholesterol, phospholipids and glycolipids, which play critical roles in cell adhesion and signal transduction during spermatogenesis. An insight into the correlation of membrane lipids with spermatogenesis helps us to better understand the mechanisms of spermatogenesis and provide new approaches to the diagnosis and treatment of male infertility.

  19. Near-haploid and low-hypodiploid acute lymphoblastic leukemia

    DEFF Research Database (Denmark)

    Safavi, Setareh; Paulsson, Kajsa

    2017-01-01

    Hypodiploidy leukemia (ALL) in both children and adults. It has long been clear by cytogenetic analyses, and recently confirmed by mutational profiling, that these cases may be further subdivided into 2 subtypes: near-haploid ALL...

  20. Chromosome length scaling in haploid, asexual reproduction

    International Nuclear Information System (INIS)

    Oliveira, P M C de

    2007-01-01

    We study the genetic behaviour of a population formed by haploid individuals which reproduce asexually. The genetic information for each individual is stored along a bit-string (or chromosome) with L bits, where 0-bits represent the wild allele and 1-bits correspond to harmful mutations. Each newborn inherits this chromosome from its parent with a few random mutations: on average a fixed number m of bits are flipped. Selection is implemented according to the number N of 1-bits counted along the individual's chromosome: the smaller N the higher the probability an individual has to survive a new time step. Such a population evolves, with births and deaths, and its genetic distribution becomes stabilized after sufficiently many generations have passed. The question we pose concerns the procedure of increasing L. The aim is to get the same distribution of genetic loads N/L among the equilibrated population, in spite of a larger L. Should we keep the same mutation rate m/L for different values of L? The answer is yes, which intuitively seems to be plausible. However, this conclusion is not trivial, according to our simulation results: the question also involves the population size

  1. Verification and characterization of chromosome duplication in haploid maize.

    Science.gov (United States)

    de Oliveira Couto, E G; Resende Von Pinho, E V; Von Pinho, R G; Veiga, A D; de Carvalho, M R; de Oliveira Bustamante, F; Nascimento, M S

    2015-06-26

    Doubled haploid technology has been used by various private companies. However, information regarding chromosome duplication methodologies, particularly those concerning techniques used to identify duplication in cells, is limited. Thus, we analyzed and characterized artificially doubled haploids using microsatellites molecular markers, pollen viability, and flow cytometry techniques. Evaluated material was obtained using two different chromosome duplication protocols in maize seeds considered haploids, resulting from the cross between the haploid inducer line KEMS and 4 hybrids (GNS 3225, GNS 3032, GNS 3264, and DKB 393). Fourteen days after duplication, plant samples were collected and assessed by flow cytometry. Further, the plants were transplanted to a field, and samples were collected for DNA analyses using microsatellite markers. The tassels were collected during anthesis for pollen viability analyses. Haploid, diploid, and mixoploid individuals were detected using flow cytometry, demonstrating that this technique was efficient for identifying doubled haploids. The microsatellites markers were also efficient for confirming the ploidies preselected by flow cytometry and for identifying homozygous individuals. Pollen viability showed a significant difference between the evaluated ploidies when the Alexander and propionic-carmin stains were used. The viability rates between the plodies analyzed show potential for fertilization.

  2. Relationship between chromosomal aberration of germ cells and dominant lethal mutation in male mice after low dosage of X-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Mingdong, Wang; Baochen, Yang; Yuke, Jin [Bethune (N.) Medical Univ., Changchun, JL (China). Dept. of Gentics

    1989-01-01

    The relationship between chromosomal aberration adn dominant mutation in spermatocytes of late pachytene phase in male mice after a single X-irridiation was reported. It was found that the frequency of aberrant cells was correlative to the rate of fetal death, the latter was being about 2.5 times as high as the former. The frequency of dominant lethal mutation induced by X-irradiation is 2.1995x10{sup -3} gamete {center dot} 10 mGy.

  3. An analysis of radiation-induced damage in the spider mite. Relationship between mortality of haploid and diploid eggs in two successive generations

    International Nuclear Information System (INIS)

    Leenhouts, H.P.; Chadwick, K.H.

    1976-01-01

    Unfertilized females of the spider mite (Tetranychus urticae) produce only haploid eggs which develop into a haploid male. Fertilized females produce both haploid eggs (unfertilized), which develop into males, and diploid eggs (fertilized), which develop into females. Radiobiological experiments performed by A.M. Feldmann (Association Euratom-ITAL) made data available on the radiation-induced mortality of haploid and diploid eggs in the F 1 and F 2 generation following irradiation of either males or females with X rays or fast neutrons. The data have been analysed using the molecular theory of cell survival where it is assumed that DNA double strand breaks, induced randomly in the cell, are the critical radiation-induced lesions, which lead to cell death. Theoretical relationships are derived for the dose dependence of hatchability in haploid and diploid eggs in the first and second generations expressed as a function of the radiation damage in the parental genome. These theoretical relationships can be used to derive the inter-relationship between the different hatchabilities, and the results from the spider mite have been analysed using these considerations. It is concluded that the radiation-induced genetic damage arises from one type of initial lesion. The eventual radiobiological implications of this analysis are discussed, expecially with respect to the transmittance of radiation-induced genetic damage after low-level radiation. (author)

  4. Estrogens and male reproduction: a new concept

    Directory of Open Access Journals (Sweden)

    S. Carreau

    2007-06-01

    Full Text Available The mammalian testis serves two main functions: production of spermatozoa and synthesis of steroids; among them estrogens are the end products obtained from the irreversible transformation of androgens by a microsomal enzymatic complex named aromatase. The aromatase is encoded by a single gene (cyp19 in humans which contains 18 exons, 9 of them being translated. In rats, the aromatase activity is mainly located in Sertoli cells of immature rats and then in Leydig cells of adult rats. We have demonstrated that germ cells represent an important source of estrogens: the amount of P450arom transcript is 3-fold higher in pachytene spermatocytes compared to gonocytes or round spermatids; conversely, aromatase activity is more intense in haploid cells. Male germ cells of mice, bank voles, bears, and monkeys express aromatase. In humans, we have shown the presence of a biologically active aromatase and of estrogen receptors (alpha and ß in ejaculated spermatozoa and in immature germ cells in addition to Leydig cells. Moreover, we have demonstrated that the amount of P450arom transcripts is 30% lower in immotile than in motile spermatozoa. Alterations of spermatogenesis in terms of number and motility of spermatozoa have been described in men genetically deficient in aromatase. These last observations, together with our data showing a significant decrease of aromatase in immotile spermatozoa, suggest that aromatase could be involved in the acquisition of sperm motility. Thus, taking into account the widespread localization of aromatase and estrogen receptors in testicular cells, it is obvious that, besides gonadotrophins and androgens, estrogens produced locally should be considered to be physiologically relevant hormones involved in the regulation of spermatogenesis and spermiogenesis.

  5. Proteomic strategy for the identification of critical actors in reorganization of the post-meiotic male genome.

    Science.gov (United States)

    Govin, Jerome; Gaucher, Jonathan; Ferro, Myriam; Debernardi, Alexandra; Garin, Jerome; Khochbin, Saadi; Rousseaux, Sophie

    2012-01-01

    After meiosis, during the final stages of spermatogenesis, the haploid male genome undergoes major structural changes, resulting in a shift from a nucleosome-based genome organization to the sperm-specific, highly compacted nucleoprotamine structure. Recent data support the idea that region-specific programming of the haploid male genome is of high importance for the post-fertilization events and for successful embryo development. Although these events constitute a unique and essential step in reproduction, the mechanisms by which they occur have remained completely obscure and the factors involved have mostly remained uncharacterized. Here, we sought a strategy to significantly increase our understanding of proteins controlling the haploid male genome reprogramming, based on the identification of proteins in two specific pools: those with the potential to bind nucleic acids (basic proteins) and proteins capable of binding basic proteins (acidic proteins). For the identification of acidic proteins, we developed an approach involving a transition-protein (TP)-based chromatography, which has the advantage of retaining not only acidic proteins due to the charge interactions, but also potential TP-interacting factors. A second strategy, based on an in-depth bioinformatic analysis of the identified proteins, was then applied to pinpoint within the lists obtained, male germ cells expressed factors relevant to the post-meiotic genome organization. This approach reveals a functional network of DNA-packaging proteins and their putative chaperones and sheds a new light on the way the critical transitions in genome organizations could take place. This work also points to a new area of research in male infertility and sperm quality assessments.

  6. Environmentally induced transgenerational epigenetic reprogramming of primordial germ cells and the subsequent germ line.

    Directory of Open Access Journals (Sweden)

    Michael K Skinner

    Full Text Available A number of environmental factors (e.g. toxicants have been shown to promote the epigenetic transgenerational inheritance of disease and phenotypic variation. Transgenerational inheritance requires the germline transmission of altered epigenetic information between generations in the absence of direct environmental exposures. The primary periods for epigenetic programming of the germ line are those associated with primordial germ cell development and subsequent fetal germline development. The current study examined the actions of an agricultural fungicide vinclozolin on gestating female (F0 generation progeny in regards to the primordial germ cell (PGC epigenetic reprogramming of the F3 generation (i.e. great-grandchildren. The F3 generation germline transcriptome and epigenome (DNA methylation were altered transgenerationally. Interestingly, disruptions in DNA methylation patterns and altered transcriptomes were distinct between germ cells at the onset of gonadal sex determination at embryonic day 13 (E13 and after cord formation in the testis at embryonic day 16 (E16. A larger number of DNA methylation abnormalities (epimutations and transcriptional alterations were observed in the E13 germ cells than in the E16 germ cells. These observations indicate that altered transgenerational epigenetic reprogramming and function of the male germline is a component of vinclozolin induced epigenetic transgenerational inheritance of disease. Insights into the molecular control of germline transmitted epigenetic inheritance are provided.

  7. Fixation Probability in a Haploid-Diploid Population.

    Science.gov (United States)

    Bessho, Kazuhiro; Otto, Sarah P

    2017-01-01

    Classical population genetic theory generally assumes either a fully haploid or fully diploid life cycle. However, many organisms exhibit more complex life cycles, with both free-living haploid and diploid stages. Here we ask what the probability of fixation is for selected alleles in organisms with haploid-diploid life cycles. We develop a genetic model that considers the population dynamics using both the Moran model and Wright-Fisher model. Applying a branching process approximation, we obtain an accurate fixation probability assuming that the population is large and the net effect of the mutation is beneficial. We also find the diffusion approximation for the fixation probability, which is accurate even in small populations and for deleterious alleles, as long as selection is weak. These fixation probabilities from branching process and diffusion approximations are similar when selection is weak for beneficial mutations that are not fully recessive. In many cases, particularly when one phase predominates, the fixation probability differs substantially for haploid-diploid organisms compared to either fully haploid or diploid species. Copyright © 2017 by the Genetics Society of America.

  8. Extragonadal Germ Cell Cancer (EGC)

    Science.gov (United States)

    The Testicular Cancer Resource Center Extragonadal Germ Cell Cancer (EGC) 95% of all testicular tumors are germ cell tumors. That is, the tumors originate in the sperm forming cells in the testicles ( ...

  9. AiGERM: A logic programming front end for GERM

    Science.gov (United States)

    Hashim, Safaa H.

    1990-01-01

    AiGerm (Artificially Intelligent Graphical Entity Relation Modeler) is a relational data base query and programming language front end for MCC (Mission Control Center)/STP's (Space Test Program) Germ (Graphical Entity Relational Modeling) system. It is intended as an add-on component of the Germ system to be used for navigating very large networks of information. It can also function as an expert system shell for prototyping knowledge-based systems. AiGerm provides an interface between the programming language and Germ.

  10. Guns, Germs and Steel

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 1. Guns, Germs and Steel - A Short History of Everybody for the Last 13,000 years. Suri Venkatachalam. Book Review Volume 6 Issue 1 January 2001 pp 84-88. Fulltext. Click here to view fulltext PDF. Permanent link:

  11. Foodborne Germs and Illnesses

    Science.gov (United States)

    ... Español (Spanish) Recommend on Facebook Tweet Share Compartir What Causes Food Poisoning? Many different disease-causing germs can contaminate ... email address: Enter Email Address What’s this? Submit What's this? Submit Button ... of Foodborne Illness in the U.S. Food Safety is a CDC Winnable Battle Foodborne Illness ...

  12. Induction of gynogenetic and androgenetic haploid and doubled haploid development in the brown trout (Salmo trutta Linnaeus 1758).

    Science.gov (United States)

    Michalik, O; Dobosz, S; Zalewski, T; Sapota, M; Ocalewicz, K

    2015-04-01

    Gynogenetic and androgenetic brown trout (Salmo trutta Linnaeus 1758) haploids (Hs) and doubled haploids (DHs) were produced in the present research. Haploid development was induced by radiation-induced genetic inactivation of spermatozoa (gynogenesis) or eggs (androgenesis) before insemination. To provide DHs, gynogenetic and androgenetic haploid zygotes were subjected to the high pressure shock to suppress the first mitotic cleavage. Among haploids, gynogenetic embryos were showing lower mortality when compared to the androgenetic embryos; however, most of them die before the first feeding stage. Gynogenetic doubled haploids provided in the course of the brown trout eggs activation performed by homologous and heterologous sperm (rainbow trout) were developing equally showing hatching rates of 14.76 ± 2.4% and 16.14 ± 2.90% and the survival rates at the first feeding stage of 10.48 ± 3.48% and 12.78 ± 2.18%, respectively. Significantly, lower survival rate was observed among androgenetic progenies from the diploid groups with only few specimens that survived to the first feeding stage. Cytogenetic survey showed that among embryos from the diploid variants of the research, only gynogenetic individuals possessed doubled sets of chromosomes. Thus, it is reasonable to assume that radiation employed for the genetic inactivation of the brown trout eggs misaligned mechanism responsible for the cell divisions and might have delayed or even arrested the first mitotic cleavage in the androgenetic brown trout zygotes. Moreover, protocol for the radiation-induced inactivation of the paternal and maternal genome should be adjusted as some of the cytogenetically surveyed gynogenetic and androgenetic embryos exhibited fragments of the irradiated chromosomes. © 2015 Blackwell Verlag GmbH.

  13. Sex-specific differences in fetal germ cell apoptosis induced by ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Guerquin, M.J.; Duquenne, C.; Coffigny, H.; Rouiller-Fabre, V.; Lambrot, R.; Habert, R.; Livera, G. [CEA, DSV/DRR/SEGG/LDRG, Laboratory of Differentiation and Radiobiology of the Gonads, Unit of Gametogenesis and Genotoxicity, F-92265 Fontenay aux Roses (France); Guerquin, M.J.; Duquenne, C.; Coffigny, H.; Rouiller-Fabre, V.; Lambrot, R.; Habert, R.; Livera, G. [Univ. Paris 7-Denis Diderot, UFR of Biology, UMR-S 566, F-92265 Fontenay aux Roses (France); Guerquin, M.J.; Duquenne, C.; Coffigny, H.; Rouiller-Fabre, V.; Lambrot, R.; Habert, R.; Livera, G. [INSERM, U566, F-92265 Fontenay aux Roses (France); Bakalska, M. [Institute of Experimental Morphology and Anthropology, Bulgarian Academy of Sciences, Sofia (Bulgaria); Frydman, R. [Univ Paris-Sud, Clamart F-92140 (France); Frydman, R. [AP-HP, Service de Gynecologie-Obstetrique et Medecine de la Reproduction, Hopital Antoine Beclere, Clamart F-92141 (France); Frydman, R. [INSERM, U782, Clamart F-92140 (France)

    2009-07-01

    Background: We have previously shown that male human fetal germ cells are highly radiosensitive and that their death depends on p53 activation. Male germ cell apoptosis was initiated with doses as low as 0.1 Gy and was prevented by pifithrin {alpha}, a p53 inhibitor. In this study, we investigated the radiosensitivity of early female and male fetal proliferating germ cells. Methods and results: Both male and female fetal germ cells displayed a similar number of {gamma}H2AX foci in response to ionizing radiation (IR). In organ culture of human fetal ovaries, the germ cells underwent apoptosis only when exposed to high doses of IR (1.5 Gy and above). Accumulation of p53 was detected in irradiated male human fetal germ cells but not in female ones. Inhibition of p53 with pifithrin {alpha} did not affect oogonia apoptosis following irradiation. IR induced apoptosis similarly in mouse fetal ovaries in organ culture and in vivo during oogonial proliferation. Germ cell survival in testes from p53 knockout or p63 knockout mice exposed to IR was better than wild-type, whereas female germ cell survival was unaffected by p53 or p63 knockout. Conclusions: These findings show that pre-meiotic male and female fetal germ cells behave differently in response to a genotoxic stress-irradiation with oogonia being less sensitive and undergoing p53-independent apoptosis. (authors)

  14. Sex-specific differences in fetal germ cell apoptosis induced by ionizing radiation

    International Nuclear Information System (INIS)

    Guerquin, M.J.; Duquenne, C.; Coffigny, H.; Rouiller-Fabre, V.; Lambrot, R.; Habert, R.; Livera, G.; Guerquin, M.J.; Duquenne, C.; Coffigny, H.; Rouiller-Fabre, V.; Lambrot, R.; Habert, R.; Livera, G.; Guerquin, M.J.; Duquenne, C.; Coffigny, H.; Rouiller-Fabre, V.; Lambrot, R.; Habert, R.; Livera, G.; Bakalska, M.; Frydman, R.; Frydman, R.; Frydman, R.

    2009-01-01

    Background: We have previously shown that male human fetal germ cells are highly radiosensitive and that their death depends on p53 activation. Male germ cell apoptosis was initiated with doses as low as 0.1 Gy and was prevented by pifithrin α, a p53 inhibitor. In this study, we investigated the radiosensitivity of early female and male fetal proliferating germ cells. Methods and results: Both male and female fetal germ cells displayed a similar number of γH2AX foci in response to ionizing radiation (IR). In organ culture of human fetal ovaries, the germ cells underwent apoptosis only when exposed to high doses of IR (1.5 Gy and above). Accumulation of p53 was detected in irradiated male human fetal germ cells but not in female ones. Inhibition of p53 with pifithrin α did not affect oogonia apoptosis following irradiation. IR induced apoptosis similarly in mouse fetal ovaries in organ culture and in vivo during oogonial proliferation. Germ cell survival in testes from p53 knockout or p63 knockout mice exposed to IR was better than wild-type, whereas female germ cell survival was unaffected by p53 or p63 knockout. Conclusions: These findings show that pre-meiotic male and female fetal germ cells behave differently in response to a genotoxic stress-irradiation with oogonia being less sensitive and undergoing p53-independent apoptosis. (authors)

  15. Evidence against a germ plasm in the milkweed bug Oncopeltus fasciatus, a hemimetabolous insect

    Directory of Open Access Journals (Sweden)

    Ben Ewen-Campen

    2013-04-01

    Primordial germ cell (PGC formation in holometabolous insects like Drosophila melanogaster relies on maternally synthesised germ cell determinants that are asymmetrically localised to the oocyte posterior cortex. Embryonic nuclei that inherit this “germ plasm” acquire PGC fate. In contrast, historical studies of basally branching insects (Hemimetabola suggest that a maternal requirement for germ line genes in PGC specification may be a derived character confined principally to Holometabola. However, there have been remarkably few investigations of germ line gene expression and function in hemimetabolous insects. Here we characterise PGC formation in the milkweed bug Oncopeltus fasciatus, a member of the sister group to Holometabola, thus providing an important evolutionary comparison to members of this clade. We examine the transcript distribution of orthologues of 19 Drosophila germ cell and/or germ plasm marker genes, and show that none of them localise asymmetrically within Oncopeltus oocytes or early embryos. Using multiple molecular and cytological criteria, we provide evidence that PGCs form after cellularisation at the site of gastrulation. Functional studies of vasa and tudor reveal that these genes are not required for germ cell formation, but that vasa is required in adult males for spermatogenesis. Taken together, our results provide evidence that Oncopeltus germ cells may form in the absence of germ plasm, consistent with the hypothesis that germ plasm is a derived strategy of germ cell specification in insects.

  16. Evidence against a germ plasm in the milkweed bug Oncopeltus fasciatus, a hemimetabolous insect.

    Science.gov (United States)

    Ewen-Campen, Ben; Jones, Tamsin E M; Extavour, Cassandra G

    2013-06-15

    Primordial germ cell (PGC) formation in holometabolous insects like Drosophila melanogaster relies on maternally synthesised germ cell determinants that are asymmetrically localised to the oocyte posterior cortex. Embryonic nuclei that inherit this "germ plasm" acquire PGC fate. In contrast, historical studies of basally branching insects (Hemimetabola) suggest that a maternal requirement for germ line genes in PGC specification may be a derived character confined principally to Holometabola. However, there have been remarkably few investigations of germ line gene expression and function in hemimetabolous insects. Here we characterise PGC formation in the milkweed bug Oncopeltus fasciatus, a member of the sister group to Holometabola, thus providing an important evolutionary comparison to members of this clade. We examine the transcript distribution of orthologues of 19 Drosophila germ cell and/or germ plasm marker genes, and show that none of them localise asymmetrically within Oncopeltus oocytes or early embryos. Using multiple molecular and cytological criteria, we provide evidence that PGCs form after cellularisation at the site of gastrulation. Functional studies of vasa and tudor reveal that these genes are not required for germ cell formation, but that vasa is required in adult males for spermatogenesis. Taken together, our results provide evidence that Oncopeltus germ cells may form in the absence of germ plasm, consistent with the hypothesis that germ plasm is a derived strategy of germ cell specification in insects.

  17. Primary pleuro-pulmonary malignant germ cell tumours.

    Directory of Open Access Journals (Sweden)

    Vaideeswar P

    2002-01-01

    Full Text Available Lungs and pleura are rare sites for malignant germ-cell tumours. Two cases, pure yolk-sac tumour and yolk sac-sac tumour/embryonal carcinoma are described in young males who presented with rapid progression of respiratory symptoms. The malignant mixed germ cell tumour occurred in the right lung, while the yolk-sac tumour had a pseudomesotheliomatous growth pattern suggesting a pleural origin. Alpha-foetoprotein was immunohistochemically demonstrated in both.

  18. DNA repair studies in mammalian germ cells

    International Nuclear Information System (INIS)

    Sega, G.A.; Owens, J.G.

    1984-01-01

    In submammalian test systems, nitrosocarbamates (NEC) are 100-fold more mutagenic than are their corresponding nitrosourea homologues. To learn more about its interaction with germ-cell DNA in the mouse testis, male mice were given i.p. injections of NEC. Testicular injections of [ 3 H]dThd were given along with the NEC. Sixteen days after treatment, sperm were recovered from the caudal epididymides and assayed for an unscheduled-DNA-synthesis

  19. The effects of quantitative fecundity in the haploid stage on reproductive success and diploid fitness in the aquatic peat moss Sphagnum macrophyllum.

    Science.gov (United States)

    Johnson, M G; Shaw, A J

    2016-06-01

    A major question in evolutionary biology is how mating patterns affect the fitness of offspring. However, in animals and seed plants it is virtually impossible to investigate the effects of specific gamete genotypes. In bryophytes, haploid gametophytes grow via clonal propagation and produce millions of genetically identical gametes throughout a population. The main goal of this research was to test whether gamete identity has an effect on the fitness of their diploid offspring in a population of the aquatic peat moss Sphagnum macrophyllum. We observed a heavily male-biased sex ratio in gametophyte plants (ramets) and in multilocus microsatellite genotypes (genets). There was a steeper relationship between mating success (number of different haploid mates) and fecundity (number of diploid offspring) for male genets compared with female genets. At the sporophyte level, we observed a weak effect of inbreeding on offspring fitness, but no effect of brood size (number of sporophytes per maternal ramet). Instead, the identities of the haploid male and haploid female parents were significant contributors to variance in fitness of sporophyte offspring in the population. Our results suggest that intrasexual gametophyte/gamete competition may play a role in determining mating success in this population.

  20. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 5: intercellular junctions and contacts between germs cells and Sertoli cells and their regulatory interactions, testicular cholesterol, and genes/proteins associated with more than one germ cell generation.

    Science.gov (United States)

    Hermo, Louis; Pelletier, R-Marc; Cyr, Daniel G; Smith, Charles E

    2010-04-01

    In the testis, cell adhesion and junctional molecules permit specific interactions and intracellular communication between germ and Sertoli cells and apposed Sertoli cells. Among the many adhesion family of proteins, NCAM, nectin and nectin-like, catenins, and cadherens will be discussed, along with gap junctions between germ and Sertoli cells and the many members of the connexin family. The blood-testis barrier separates the haploid spermatids from blood borne elements. In the barrier, the intercellular junctions consist of many proteins such as occludin, tricellulin, and claudins. Changes in the expression of cell adhesion molecules are also an essential part of the mechanism that allows germ cells to move from the basal compartment of the seminiferous tubule to the adluminal compartment thus crossing the blood-testis barrier and well-defined proteins have been shown to assist in this process. Several structural components show interactions between germ cells to Sertoli cells such as the ectoplasmic specialization which are more closely related to Sertoli cells and tubulobulbar complexes that are processes of elongating spermatids embedded into Sertoli cells. Germ cells also modify several Sertoli functions and this also appears to be the case for residual bodies. Cholesterol plays a significant role during spermatogenesis and is essential for germ cell development. Lastly, we list genes/proteins that are expressed not only in any one specific generation of germ cells but across more than one generation. Copyright 2009 Wiley-Liss, Inc.

  1. Meiosis and Haploid Gametes in the Pathogen Trypanosoma brucei

    OpenAIRE

    Peacock, Lori; Bailey, Mick; Carrington, Mark; Gibson, Wendy

    2014-01-01

    Summary In eukaryote pathogens, sex is an important driving force in spreading genes for drug resistance, pathogenicity, and virulence [1]. For the parasitic trypanosomes that cause African sleeping sickness, mating occurs during transmission by the tsetse vector [2, 3] and involves meiosis [4], but haploid gametes have not yet been identified. Here, we show that meiosis is a normal part of development in the insect salivary glands for all subspecies of Trypanosoma brucei, including the human...

  2. Assessment of mutagenic damage by monofunctional alkylating agents and gamma radiation in haploid and diploid frogs, Xenopus laevis

    International Nuclear Information System (INIS)

    Hart, D.R.; Armstrong, J.B.

    1984-01-01

    Adult male South African clawed frogs, Xenopus laevis, were mutagenized by 3-day immersion in aqueous solutions of ethyl methanesulfonate (EMS), diethyl nitrosamine (DEN), or ethyl nitrosourea (ENU), or by acute exposure to gamma radiation. They were then spawned repeatedly at 2-week intervals with untreated females, and embryonic survival of the progeny was used to assess genetic damage. Recessive lethal effects were assessed from reduced survival of androgenetic haploid progeny. Neither recessive nor dominant lethal effects were obtained after exposure to 100 mg/liter EMS or 2 g/liter DEN. At 250 mg/liter EMS, peak dominant lethality occurred 3-5 weeks after treatment. Most embryos hatched, but many were abnormal and died shortly after hatching. Haploid survival was significantly reduced over a broader period, from 1 to 13 weeks after mutagenesis. Treatment with 75 mg/liter ENU produced effects similar to the 250-mg/liter EMS mutagenesis. At 400 mg/liter EMS, the frequency and severity of the effects on both diploid and haploid embryos were increased over the lower dose. Gamma irradiation at 1500 R produced effects similar to the 400-mg/liter mutagenesis, except that peak dominant lethality extended from 1 to 7 weeks

  3. Germ killing by ultraviolet radiation

    International Nuclear Information System (INIS)

    Wawrik, O.

    1975-01-01

    Short-wave UV radiation, in particular the range about 250 nm, has a high germ reducing effect. Corresponding UV burners which above all emit radiation at the line of 254 nm can therefore be used effectively in all cases where the least possible content of germs in the air is aimed at. Apart from this it is also possible to reduce by this process the germs on surfaces and liquids. Especially in the most various ranges of pharmaceutical production one is steadily striving for efficient and last not least economic procedures by which it is possible to reduce the germs present in the air of a room. Numerous scientific investigations have sufficiently proved that short-wave UV radiation is extremely well appropriate for such purposes. Absolutely germ-free air in a room can only be obtained under laboratory conditions. In practice, however, the aim is not to achieve a 100 per cent killing of the germs present in a room but to make sure that the germ rate in certain rooms is constantly reduced to the lowest possible level. If in this connection it is referred to a germ reduction of 100 or 99 per cent this is but theory. (orig.) [de

  4. Cytomorphological studies in X-ray induced glandless haploids in Gossypium hirsutum L. (cotton)

    Energy Technology Data Exchange (ETDEWEB)

    Mehetre, S.S.; Thombre, M.V. (Mahatma Phule Krishi Vidyapeeth, Rahuri (India))

    1981-08-01

    Six haploid plants were obtained in M/sub 2/ generation of the 25 kr. X-ray irradiated Gossypium hirsutum L. cotton variety H.G. 108. The cytomorphological studies on these plants indicated highly irregular meiosis, giving on an average six bivalents, the range being 0-9. Unequal separation of chromosomes and chromatids at anaphase-1 and II respectively led to formation of abnormal tetrads and pollens with high size variations leading to high pollen sterility. These plants were characterized by miniature stature, shorter stem and internodes, smaller leaves, flowers and stomata with fewer chloroplasts, male and female sterility and halving of chromosomes. The reduction in morphological characters was nearly in the proportion of 1:2 as compared to their diploid counterparts. 31 refs.; 5 tables; 12 figures.

  5. Germ Cell Tumor Located in the Midline of the Anterior Neck

    OpenAIRE

    Tatyana PIRDOPSKA; Ivan TERZIEV; Sv. HRISTOVA; W. MLADENOVSKY; R. PETKOV

    2011-01-01

    Primary germ cell tumors involving midline of the anterior neck are extremely rare. Here we report a 68-year-old male who was operated due to a mass lesion in the anterior neck with infiltration of the isthmus of the thyroid gland. Histopathological examination revealed a germ cell tumor with extragonadal localization in the anterior neck infiltrating the isthmus of the thyroid gland.

  6. Dramatic improvement in genome assembly achieved using doubled-haploid genomes.

    Science.gov (United States)

    Zhang, Hong; Tan, Engkong; Suzuki, Yutaka; Hirose, Yusuke; Kinoshita, Shigeharu; Okano, Hideyuki; Kudoh, Jun; Shimizu, Atsushi; Saito, Kazuyoshi; Watabe, Shugo; Asakawa, Shuichi

    2014-10-27

    Improvement in de novo assembly of large genomes is still to be desired. Here, we improved draft genome sequence quality by employing doubled-haploid individuals. We sequenced wildtype and doubled-haploid Takifugu rubripes genomes, under the same conditions, using the Illumina platform and assembled contigs with SOAPdenovo2. We observed 5.4-fold and 2.6-fold improvement in the sizes of the N50 contig and scaffold of doubled-haploid individuals, respectively, compared to the wildtype, indicating that the use of a doubled-haploid genome aids in accurate genome analysis.

  7. Evaluasi keseragaaman, keragaman, dan kestabilan karakter agronomi galur-galur padi haploid ganda hasil kultur antera

    Directory of Open Access Journals (Sweden)

    PRIATNA SASMITA

    2011-05-01

    Full Text Available Sasmita P. 2011. Evaluasi keseragaman, keragaman, dan kestabilan karakter agronomi galur-galur padi haploid ganda hasil kultur antera. Bioteknologi 8: 10-17. Pembentukan galur haploid ganda dalam kultur antera bertujuan untuk mempercepat perolehan galur murni. Seleksi karakter yang diinginkan dapat dilakukan langsung terhadap progeni hasil kultur antera pada generasi awal. Percobaan ini bertujuan untuk mengetahui karakteristik agronomi, keseragaman, dan kestabilan galur haploid ganda, serta mendapatkan putatif galur-gallur haploid ganda sebagai bahan evaluasi lebih lanjut untuk mendapatkan galur harapan. Percobaan pertama menggunakan rancangan acak lengkap diulang lima kali. Perlakuannya aadalah 111 galur haploid ganda hasil kultur antera generasi pertama (DH1. Percobaan kedua menggunakan rancangan petak terpisah dengan perlakuan petak utama adalah galur haploid ganda hasil kultur antera dan perlakuan anak petaknya generasi galur haploid ganda kedua (DH2 hingga kelima (DDH5. Hasil percobaan menunjukkan bahwa setiap tanaman dalam galur yang sama memiliki karakter agronnomi seragam, sedangkan tanaman antar galur berbeda memiliki karakter agronomi beragam. Hasil evaluasi lebih lanjut terhadap tiga dari 111 galur haploid ganda yang berasal dari generasi kedua hingga kelima menunjukkan tidak terdapat perbedaan karakter antar generasi untuk setiap p galur yang sama. Hasil penelitian tersebut menunjukkan pula bahwa karakteristik agronomi galur haploid ganda stabil dari generasi ke generasi.

  8. Evaluating the Production of Doubled Haploid Wheat Lines Using Various Methods of Wheat and Maize Crossing to Develop Heat-Tolerant Wheat Varieties

    Directory of Open Access Journals (Sweden)

    Tayebeh BAKHSHI

    2017-02-01

    Full Text Available Abstract. In this study, chromosome elimination method was used to develop doubled haploid wheat lines via crosses with maize. The plant materials used included 11, F1 wheat genotypes and maize genotype BC572. In these crosses, the maize plant was used as the male parent.Three methods of haploid production in wheat comprising conventional (A, detached-tiller culture (B and intermediate (C techniques were used and compared. The traits such as the number of seeds set, the number of embryos obtained and the number of haploid seedlings produced were studied. Comparisons showed that among various methods of storing wheat spikes, method (C was better than other techniques in terms of the percentage of seed production, embryo formation and haploid seedling production. Also, in all three methods, the percentage of seed production, the percentage of embryo formation and the percentage of haploid seedling production were respectively equal to 76.84, 25.22 and 51.89. Among the wheat genotypes in all three methods, genotype DH-133 with 87.28 percent seed set and genotype DH-132 with 32.71 percent embryo formation and 65.08 percent haploid seedling production were the best genotypes. A total of 92 doubled haploid lines were produced. In the field evaluations of 86 doubled haploid lines, traits such as growing season, plant height, lodging, kernel yield and 1000 kernel weight were examined. Finally, 3 lines were selected for adaptation and stability testing under heat stress conditions.Keywords: Wheat, Doubled haploid, Chromosome elimination, Detached-tiller culture Özet. Bu çalışmada, mısır ile çaprazlarla çift katlı haploid buğday hatlarının geliştirilmesi için kromozom eliminasyon yöntemi kullanılmıştır. Kullanılan bitki materyalleri 11, F1 buğday genotipleri ve BC572 mısır genotipini içermektedir. Bu çaprazlarda, mısır bitkisi erkek ebeveyn olarak kullanılmıştır. Geleneksel (A, ayrık-yeke kültürü (B ve ara (C

  9. Development of a doubled haploid system for wheat through wheat ...

    African Journals Online (AJOL)

    La variété de maïs Kelvedon glory, avait la meilleure réponse parmi les variétés des maïs. Des considérables différences variétales dans le rendement de production d'haploides étaient évidentes à la fois dans les variétés de blé et de maïs. Mots Clés: Plantes homozygènes, protocole de rendement, Tritium aestivum, Zea ...

  10. Developmental arrest of germ cells in the pathogenesis of germ cell neoplasia

    DEFF Research Database (Denmark)

    Rajpert-De Meyts, E; Jørgensen, N; Brøndum-Nielsen, K

    1998-01-01

    Clinical observations and epidemiological evidence suggest that important aetiopathological events that cause neoplastic transformation of the male germ cell may occur in fetal life or early infancy. The incidence of germ cell neoplasia is high in individuals with various disorders of gonadal...... development and sexual differentiation, such as gonadal dysgenesis or androgen insensitivity syndrome. Increased risk has also been noted in individuals with trisomy 21, idiopathic infertility and low birth weight. Infertility is sometimes associated with small aberrations of sex chromosomes (e.g. low...... frequency mosaicism XY/XO) which can also be found in patients with testicular cancer. The variety of conditions that predispose to testicular neoplasia and the rise in its incidence in many countries speaks for the influence of environmental factors which may affect genetically predisposed individuals. We...

  11. Meiosis and haploid gametes in the pathogen Trypanosoma brucei.

    Science.gov (United States)

    Peacock, Lori; Bailey, Mick; Carrington, Mark; Gibson, Wendy

    2014-01-20

    In eukaryote pathogens, sex is an important driving force in spreading genes for drug resistance, pathogenicity, and virulence. For the parasitic trypanosomes that cause African sleeping sickness, mating occurs during transmission by the tsetse vector and involves meiosis, but haploid gametes have not yet been identified. Here, we show that meiosis is a normal part of development in the insect salivary glands for all subspecies of Trypanosoma brucei, including the human pathogens. By observing insect-derived trypanosomes during the window of peak expression of meiosis-specific genes, we identified promastigote-like (PL) cells that interacted with each other via their flagella and underwent fusion, as visualized by the mixing of cytoplasmic red and green fluorescent proteins. PL cells had a short, wide body, a very long anterior flagellum, and either one or two kinetoplasts, but only the anterior kinetoplast was associated with the flagellum. Measurement of nuclear DNA contents showed that PL cells were haploid relative to diploid metacyclics. Trypanosomes are among the earliest diverging eukaryotes, and our results support the hypothesis that meiosis and sexual reproduction are ubiquitous in eukaryotes and likely to have been early innovations. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Genetical Studies On Haploid Production In Some Ornamental Plants

    International Nuclear Information System (INIS)

    MOSTAFA, M.A.M.

    2013-01-01

    Haploid are plants with a gametophytic chromosome number and doubled haploid are dihaploids that have undergone chromosome duplication. The production of haploid and doubled haploid (DHs) through gametic embryogenesis allows a single-step development of complete homozygous lines from heterozygous parents, shortening the time required to produce homozygous plants in comparison with the conventional breeding methods that employ several generations of selfing. The production of haploid and DHs provides a particularly attractive biotechnological tool, and the development of haploidy technology and protocols to produce homozygous plants has had a significant impact on agricultural systems. Nowadays, these bio technologies represent an integral part of the breeding programmes of many agronomically important crops. There are several available methods to obtain haploid and DHs, of which in vitro anther or isolated microspore culture are the most effective and widely used (Germana Maria 2011). Tissue culture techniques, particularly short-term culture procedures such as shoot-tip culture and regeneration from primary explants, have been proposed as methods for obtaining large numbers of plants identical to the plant used as an explant source( Evans et al., 1984). Nicotiana spp. are one of the most important commercial crops in the world ( Liu and Zhang, 2008). Nicotiana alata is member from family solanacea, it is ornamental plant and the diploid cells contains 18 chromosomes. Nitsch (1969) reported the first production of haploid plants through anther culture and regeneration of plants of Nicotiana alata, For these reasons they have been considered to suitable candidates for model species in somatic cell genetics research( Bourgin et al., 1979). Radiobiological studies on plant tissues in culture may provide information on the cell growth behavior, radiosensitivity and the induction of mutations. The radiosensitivity of plants and calli can be manifested mostly in three

  13. Characterization of germ cell-specific expression of the orphan nuclear receptor, germ cell nuclear factor.

    Science.gov (United States)

    Katz, D; Niederberger, C; Slaughter, G R; Cooney, A J

    1997-10-01

    Nuclear receptors, such as those for androgens, estrogens, and progesterones, control many reproductive processes. Proteins with structures similar to these receptors, but for which ligands have not yet been identified, have been termed orphan nuclear receptors. One of these orphans, germ cell nuclear factor (GCNF), has been shown to be germ cell specific in the adult and, therefore, may also participate in the regulation of reproductive functions. In this paper, we examine more closely the expression patterns of GCNF in germ cells to begin to define spatio-temporal domains of its activity. In situ hybridization showed that GCNF messenger RNA (mRNA) is lacking in the testis of hypogonadal mutant mice, which lack developed spermatids, but is present in the wild-type testis. Thus, GCNF is, indeed, germ cell specific in the adult male. Quantitation of the specific in situ hybridization signal in wild-type testis reveals that GCNF mRNA is most abundant in stage VII round spermatids. Similarly, Northern analysis and specific in situ hybridization show that GCNF expression first occurs in testis of 20-day-old mice, when round spermatids first emerge. Therefore, in the male, GCNF expression occurs postmeiotically and may participate in the morphological changes of the maturing spermatids. In contrast, female expression of GCNF is shown in growing oocytes that have not completed the first meiotic division. Thus, GCNF in the female is expressed before the completion of meiosis. Finally, the nature of the two different mRNAs that hybridize to the GCNF complementary DNA was studied. Although both messages contain the DNA binding domain, only the larger message is recognized by a probe from the extreme 3' untranslated region. In situ hybridization with these differential probes demonstrates that both messages are present in growing oocytes. In addition, the coding region and portions of the 3' untranslated region of the GCNF complementary DNA are conserved in the rat.

  14. Role of Axumin PET Scan in Germ Cell Tumor

    Science.gov (United States)

    2018-05-01

    Testis Cancer; Germ Cell Tumor; Testicular Cancer; Germ Cell Tumor of Testis; Germ Cell Tumor, Testicular, Childhood; Testicular Neoplasms; Testicular Germ Cell Tumor; Testicular Yolk Sac Tumor; Testicular Choriocarcinoma; Testicular Diseases; Germ Cell Cancer Metastatic; Germ Cell Neoplasm of Retroperitoneum; Germ Cell Cancer, Nos

  15. Molecular dosimetry of chemical mutagens: measurement of molecular dose and DNA repair germ cells

    International Nuclear Information System (INIS)

    Sega, G.A.

    1975-01-01

    Molecular dosimetry in the germ cells of male mice is reviewed with regard to in vivo alkylation of sperm heads, in vivo alkylation of sperm DNA, and possible alkylation of sperm protamine. DNA repair in male germ cells is reviewed with regard to basic design of experiments, DNA repair in various stages of spermatogenesis, effect of protamine on DNA repair following treatment with EMS or x radiation, and induction of DNA repair by methyl methanesulfonate, propyl methanesulfonate, and isopropyl methanesulfonate

  16. Immature germ cells in semen - correlation with total sperm count and sperm motility.

    Science.gov (United States)

    Patil, Priya S; Humbarwadi, Rajendra S; Patil, Ashalata D; Gune, Anita R

    2013-07-01

    Current data regarding infertility suggests that male factor contributes up to 30% of the total cases of infertility. Semen analysis reveals the presence of spermatozoa as well as a number of non-sperm cells, presently being mentioned in routine semen report as "round cells" without further differentiating them into leucocytes or immature germ cells. The aim of this work was to study a simple, cost-effective, and convenient method for differentiating the round cells in semen into immature germ cells and leucocytes and correlating them with total sperm counts and motility. Semen samples from 120 males, who had come for investigation for infertility, were collected, semen parameters recorded, and stained smears studied for different round cells. Statistical analysis of the data was done to correlate total sperm counts and sperm motility with the occurrence of immature germ cells and leucocytes. The average shedding of immature germ cells in different groups with normal and low sperm counts was compared. The clinical significance of "round cells" in semen and their differentiation into leucocytes and immature germ cells are discussed. Round cells in semen can be differentiated into immature germ cells and leucocytes using simple staining methods. The differential counts mentioned in a semen report give valuable and clinically relevant information. In this study, we observed a negative correlation between total count and immature germ cells, as well as sperm motility and shedding of immature germ cells. The latter was statistically significant with a P value 0.000.

  17. Germ cells are not required to establish the female pathway in mouse fetal gonads.

    Directory of Open Access Journals (Sweden)

    Danielle M Maatouk

    Full Text Available The fetal gonad is composed of a mixture of somatic cell lineages and germ cells. The fate of the gonad, male or female, is determined by a population of somatic cells that differentiate into Sertoli or granulosa cells and direct testis or ovary development. It is well established that germ cells are not required for the establishment or maintenance of Sertoli cells or testis cords in the male gonad. However, in the agametic ovary, follicles do not form suggesting that germ cells may influence granulosa cell development. Prior investigations of ovaries in which pre-meiotic germ cells were ablated during fetal life reported no histological changes during stages prior to birth. However, whether granulosa cells underwent normal molecular differentiation was not investigated. In cases where germ cell loss occurred secondary to other mutations, transdifferentiation of granulosa cells towards a Sertoli cell fate was observed, raising questions about whether germ cells play an active role in establishing or maintaining the fate of granulosa cells. We developed a group of molecular markers associated with ovarian development, and show here that the loss of pre-meiotic germ cells does not disrupt the somatic ovarian differentiation program during fetal life, or cause transdifferentiation as defined by expression of Sertoli markers. Since we do not find defects in the ovarian somatic program, the subsequent failure to form follicles at perinatal stages is likely attributable to the absence of germ cells rather than to defects in the somatic cells.

  18. Germ Cells Are Not Required to Establish the Female Pathway in Mouse Fetal Gonads

    Science.gov (United States)

    Maatouk, Danielle M.; Mork, Lindsey; Hinson, Ashley; Kobayashi, Akio; McMahon, Andrew P.; Capel, Blanche

    2012-01-01

    The fetal gonad is composed of a mixture of somatic cell lineages and germ cells. The fate of the gonad, male or female, is determined by a population of somatic cells that differentiate into Sertoli or granulosa cells and direct testis or ovary development. It is well established that germ cells are not required for the establishment or maintenance of Sertoli cells or testis cords in the male gonad. However, in the agametic ovary, follicles do not form suggesting that germ cells may influence granulosa cell development. Prior investigations of ovaries in which pre-meiotic germ cells were ablated during fetal life reported no histological changes during stages prior to birth. However, whether granulosa cells underwent normal molecular differentiation was not investigated. In cases where germ cell loss occurred secondary to other mutations, transdifferentiation of granulosa cells towards a Sertoli cell fate was observed, raising questions about whether germ cells play an active role in establishing or maintaining the fate of granulosa cells. We developed a group of molecular markers associated with ovarian development, and show here that the loss of pre-meiotic germ cells does not disrupt the somatic ovarian differentiation program during fetal life, or cause transdifferentiation as defined by expression of Sertoli markers. Since we do not find defects in the ovarian somatic program, the subsequent failure to form follicles at perinatal stages is likely attributable to the absence of germ cells rather than to defects in the somatic cells. PMID:23091613

  19. Diploid male production in a leaf-cutting ant

    DEFF Research Database (Denmark)

    Armitage, S.; Boomsma, J.; Baer, Boris

    2010-01-01

    1. In haplodiploid social insects where males are haploid and females are diploid, inbreeding depression is expressed as the production of diploid males when homozygosity at the sex-determining locus results in the production of diploid individuals with a male phenotype. Diploid males are often a...

  20. Exact Markov chains versus diffusion theory for haploid random mating.

    Science.gov (United States)

    Tyvand, Peder A; Thorvaldsen, Steinar

    2010-05-01

    Exact discrete Markov chains are applied to the Wright-Fisher model and the Moran model of haploid random mating. Selection and mutations are neglected. At each discrete value of time t there is a given number n of diploid monoecious organisms. The evolution of the population distribution is given in diffusion variables, to compare the two models of random mating with their common diffusion limit. Only the Moran model converges uniformly to the diffusion limit near the boundary. The Wright-Fisher model allows the population size to change with the generations. Diffusion theory tends to under-predict the loss of genetic information when a population enters a bottleneck. 2010 Elsevier Inc. All rights reserved.

  1. Improvement of ethanol-tolerance of haploid Saccharomyces diastaticus

    International Nuclear Information System (INIS)

    Song, S.H.; Kim, K.; Lee, M.W.

    1994-01-01

    Several mutation procedures have been compared to obtain an ethanol-tolerant Saccharomyces diastaticus strain secreting glucoamylase. These procedures include spontaneous mutation, EMS treatment, UV irradiation, and combination of EMS treatment and UV irradiation. All these methods were followed by adaptation of the yeast cells to gradually higher ethanol concentration. Among these procedures, the combined method of EMS treatment and UV irradiation gave the promising result, i.e. the ethanol tolerance of the yeast increased from 11.5%(v/v) to 14.0%(v/v). Respiratory deficient petite mutants of industrial and ethanol-tolerant yeast strains have been isolated and hybridized with haploid S. diastaticus strains. The resulting hybrids showed increased ethanol tolerance and starch-fermentability

  2. Techniques of radiation induced haploid breeding of wheat

    International Nuclear Information System (INIS)

    Xuan Pu; Xu Liyuan; Qu Shihong; Yu Guirong; Yin Chunrong; Yue Chunfang

    2000-01-01

    With the treatment of different doses of 60 Co γ-ray irradiation to F 1 hybrid seeds and donor plants from M 1 F 1 or M 2 F 2 , wheat anther culture was made based on the media of MW 14 and modified MS. A series of studies on the applied doses of radiation induction, low temperature treatment on donor spikes and calli, variable temperature induced incubation and yield of pollen callus and calli giving green plant lets, pollen plant lets control over summertime and pollen plant let transplantation were carried out in order to increase the efficiency of obtaining double haploid-pure diploid plant lets of wheat with stable heredity and propagation. Theses plant lets could be used directly in rapid breeding

  3. Mutagenesis and haploid culture for disease resistance in Brassica napus

    Energy Technology Data Exchange (ETDEWEB)

    MacDonald, M V; Ahmad, I; Ingram, D S [Botany School, University of Cambridge, Cambridge (United Kingdom)

    1990-01-01

    Full text: Most winter oilseed rape cultivars share parentage and therefore show little genetic diversity. There is no known resistance to Alternaria spp. in oilseed rape or in any related Brassica species. Experiments with tissue culture yielded only transient, non-genetic resistance. Therefore, mutagenesis may be used to generate heritable resistance to Alternaria spp. Gamma irradiation was applied to seeds of 'Bienvenue', secondary embryoids of cvs 'Primor' and 'Rapora', and buds of cvs 'Primor' and 'Ariana'. Isolated microspores from cv 'Ariana' and rapid cycling B. napus were also treated. The doses used ranged from 0-100 Gy for isolated microspores and buds, up to 600 Gy for seeds and 960 Gy for secondary embryoids. EMS was used to treat seeds of line WRG-42 (supplied by Nickersons RPB) and microspores of cv 'Bienvenue' and rapid cycling B. napus. Seeds were treated with up to 2.0% EMS for 0.2 h. before plating them on the culture medium. Seed irradiation up to 600 Gy did not reduce germination. M{sub 1} and M{sub 2} progenies were tested both in the laboratory and in field trials, and none of these were found to be resistant to Alternaria. However, considerable variation for other characters was observed. Haploid cultures from these plants were extremely difficult to regenerate, and for this reason no regenerant plants have been tested for resistance. For irradiated secondary embryoids the regeneration capacity decreased with increasing dose. Regenerated plants have been tested for resistance to Alternaria, but stable resistance was not observed. Haploid cultures were obtained from irradiated buds, using both anther and microspore culture. Low irradiation treatment was beneficial to developing embryoids. Some regenerants have been obtained from EMS treated microspores and seeds. Four plants have repeatedly given increased levels of resistance to A. brassicicola, and progenies are being tested to determine the genetic nature of the resistance. (author)

  4. Generation of doubled haploid transgenic wheat lines by microspore transformation.

    Directory of Open Access Journals (Sweden)

    Rhoda A T Brew-Appiah

    Full Text Available Microspores can be induced to develop homozygous doubled haploid plants in a single generation. In the present experiments androgenic microspores of wheat have been genetically transformed and developed into mature homozygous transgenic plants. Two different transformation techniques were investigated, one employing electroporation and the other co-cultivation with Agrobacterium tumefaciens. Different tissue culture and transfection conditions were tested on nine different wheat cultivars using four different constructs. A total of 19 fertile transformants in five genotypes from four market classes of common wheat were recovered by the two procedures. PCR followed by DNA sequencing of the products, Southern blot analyses and bio/histo-chemical and histological assays of the recombinant enzymes confirmed the presence of the transgenes in the T0 transformants and their stable inheritance in homozygous T1∶2 doubled haploid progenies. Several decisive factors determining the transformation and regeneration efficiency with the two procedures were determined: (i pretreatment of immature spikes with CuSO4 solution (500 mg/L at 4°C for 10 days; (ii electroporation of plasmid DNA in enlarged microspores by a single pulse of ∼375 V; (iii induction of microspores after transfection at 28°C in NPB-99 medium and regeneration at 26°C in MMS5 medium; (iv co-cultivation with Agrobacterium AGL-1 cells for transfer of plasmid T-DNA into microspores at day 0 for <24 hours; and (v elimination of AGL-1 cells after co-cultivation with timentin (200-400 mg/L.

  5. Mutagenesis and haploid culture for disease resistance in Brassica napus

    International Nuclear Information System (INIS)

    MacDonald, M.V.; Ahmad, I.; Ingram, D.S.

    1990-01-01

    Full text: Most winter oilseed rape cultivars share parentage and therefore show little genetic diversity. There is no known resistance to Alternaria spp. in oilseed rape or in any related Brassica species. Experiments with tissue culture yielded only transient, non-genetic resistance. Therefore, mutagenesis may be used to generate heritable resistance to Alternaria spp. Gamma irradiation was applied to seeds of 'Bienvenue', secondary embryoids of cvs 'Primor' and 'Rapora', and buds of cvs 'Primor' and 'Ariana'. Isolated microspores from cv 'Ariana' and rapid cycling B. napus were also treated. The doses used ranged from 0-100 Gy for isolated microspores and buds, up to 600 Gy for seeds and 960 Gy for secondary embryoids. EMS was used to treat seeds of line WRG-42 (supplied by Nickersons RPB) and microspores of cv 'Bienvenue' and rapid cycling B. napus. Seeds were treated with up to 2.0% EMS for 0.2 h. before plating them on the culture medium. Seed irradiation up to 600 Gy did not reduce germination. M 1 and M 2 progenies were tested both in the laboratory and in field trials, and none of these were found to be resistant to Alternaria. However, considerable variation for other characters was observed. Haploid cultures from these plants were extremely difficult to regenerate, and for this reason no regenerant plants have been tested for resistance. For irradiated secondary embryoids the regeneration capacity decreased with increasing dose. Regenerated plants have been tested for resistance to Alternaria, but stable resistance was not observed. Haploid cultures were obtained from irradiated buds, using both anther and microspore culture. Low irradiation treatment was beneficial to developing embryoids. Some regenerants have been obtained from EMS treated microspores and seeds. Four plants have repeatedly given increased levels of resistance to A. brassicicola, and progenies are being tested to determine the genetic nature of the resistance. (author)

  6. In vitro wheat haploid embryo production by wheat x maize cross system under different environmental conditions

    International Nuclear Information System (INIS)

    Khan, M.A.; Ahmad, J.

    2011-01-01

    Haploids are helpful in studies for inter genomic relationship, identifying molecular markers, reducing time period of varietal development and increasing efficiency of breeding program. In case of bread wheat (Triticum aestivum L.), wheat x maize cross system is the most successful system due to its higher efficiency, more haploid embryo production and low genetic specificity. The haploid embryo production is affected by many factors i.e. light, temperature, relative humidity and tiller culture media. A study was carried out comprising 25 genotypes of bread wheat for haploid embryo production using 100 mgL/sup -1/ 2,4-D, 40Gl/sup -1/ Sucrose and 8mlL/sup -1/ Sulphurous acid. Haploid embryo production was observed at various levels of environmental factors i.e. maize pollen collection temperature, time of pollination after tiller emasculation, light intensity and relative humidity during haploid seed formation. Maximum haploid embryo formation recorded was 9.52%. Best temperature observed for pollination was 21-26 degree C, optimum time duration for pollination was 24 hours after emasculation, light intensity was 10,000 Lux and relative humidity was 60-65% at 20-22 degree C. (author)

  7. Radiation- induced aneuploidy in mammalian germ cells

    International Nuclear Information System (INIS)

    Tease, C.

    1989-01-01

    The ability of ionizing radiation to induce aneuploidy in mammalian germ cells has been investigated experimentally in the laboratory mouse using a variety of cytogenetic and genetic methods. These studies have provided unambiguous evidence of induced nondisjunction in both male and female germ cells when the effect of irradiation is screened in meiotic cells or preimplantation embryos. In contrast, however, cytogenetic analyses of post-implantation embryos and genetic assays for induced chromosome gains have not found a significant radiation effect. These apparently contradictory findings may be reconciled if (a) radiation induces tertiary rather than primary trisomy, or (b) induces embryo-lethal genetic damage, such as deletions, in addition to numerical anomalies. Either or both of these explanations may account for the apparent loss during gestation of radiation-induced trisomic embryos. Extrapolating from the information so far available, it seems unlikely that environmental exposure to low doses if low dose rate radiation will result in a detectable increase in the rate of aneuploidy in the human population. (author)

  8. Identification of genes expressed in the hermaphrodite germ line of C. elegans using SAGE

    Science.gov (United States)

    Wang, Xin; Zhao, Yongjun; Wong, Kim; Ehlers, Peter; Kohara, Yuji; Jones, Steven J; Marra, Marco A; Holt, Robert A; Moerman, Donald G; Hansen, Dave

    2009-01-01

    Background Germ cells must progress through elaborate developmental stages from an undifferentiated germ cell to a fully differentiated gamete. Some of these stages include exiting mitosis and entering meiosis, progressing through the various stages of meiotic prophase, adopting either a male (sperm) or female (oocyte) fate, and completing meiosis. Additionally, many of the factors needed to drive embryogenesis are synthesized in the germ line. To increase our understanding of the genes that might be necessary for the formation and function of the germ line, we have constructed a SAGE library from hand dissected C. elegans hermaphrodite gonads. Results We found that 4699 genes, roughly 21% of all known C. elegans genes, are expressed in the adult hermaphrodite germ line. Ribosomal genes are highly expressed in the germ line; roughly four fold above their expression levels in the soma. We further found that 1063 of the germline-expressed genes have enriched expression in the germ line as compared to the soma. A comparison of these 1063 germline-enriched genes with a similar list of genes prepared using microarrays revealed an overlap of 460 genes, mutually reinforcing the two lists. Additionally, we identified 603 germline-enriched genes, supported by in situ expression data, which were not previously identified. We also found >4 fold enrichment for RNA binding proteins in the germ line as compared to the soma. Conclusion Using multiple technological platforms provides a more complete picture of global gene expression patterns. Genes involved in RNA metabolism are expressed at a significantly higher level in the germ line than the soma, suggesting a stronger reliance on RNA metabolism for control of the expression of genes in the germ line. Additionally, the number and expression level of germ line expressed genes on the X chromosome is lower than expected based on a random distribution. PMID:19426519

  9. Identification of genes expressed in the hermaphrodite germ line of C. elegans using SAGE

    Directory of Open Access Journals (Sweden)

    Holt Robert A

    2009-05-01

    Full Text Available Abstract Background Germ cells must progress through elaborate developmental stages from an undifferentiated germ cell to a fully differentiated gamete. Some of these stages include exiting mitosis and entering meiosis, progressing through the various stages of meiotic prophase, adopting either a male (sperm or female (oocyte fate, and completing meiosis. Additionally, many of the factors needed to drive embryogenesis are synthesized in the germ line. To increase our understanding of the genes that might be necessary for the formation and function of the germ line, we have constructed a SAGE library from hand dissected C. elegans hermaphrodite gonads. Results We found that 4699 genes, roughly 21% of all known C. elegans genes, are expressed in the adult hermaphrodite germ line. Ribosomal genes are highly expressed in the germ line; roughly four fold above their expression levels in the soma. We further found that 1063 of the germline-expressed genes have enriched expression in the germ line as compared to the soma. A comparison of these 1063 germline-enriched genes with a similar list of genes prepared using microarrays revealed an overlap of 460 genes, mutually reinforcing the two lists. Additionally, we identified 603 germline-enriched genes, supported by in situ expression data, which were not previously identified. We also found >4 fold enrichment for RNA binding proteins in the germ line as compared to the soma. Conclusion Using multiple technological platforms provides a more complete picture of global gene expression patterns. Genes involved in RNA metabolism are expressed at a significantly higher level in the germ line than the soma, suggesting a stronger reliance on RNA metabolism for control of the expression of genes in the germ line. Additionally, the number and expression level of germ line expressed genes on the X chromosome is lower than expected based on a random distribution.

  10. A review of methods for the production of haploids in seed plants

    International Nuclear Information System (INIS)

    Brunkener, L.

    1974-01-01

    This paper is a review of the methods which have been tried to produce haploids in seed plants. Because of their unique genetic constitution the haploids provide useful material for the study of various fundamental cytological and genetic problems. Thus the diploidization of haploids in conifers and subsequent intercrossing might allow the use of the same breeding technique as those which have been used with great success in maize breeding. Induced parthenogenesis in angiosperms has led to the formation of haploids in at least 25 genera but the number of plants obtained is generally too low for a practical utilization. The most promising method in angiosperms is in vitro cultivation of anthers which has hitherto yielded haploids in relatively large numbers in at least l5 genera but certainly can be applied with success in many more. Isolation of protoplasts or whole cells of diploid and haploid tissues and regeneration of entire plants from these protoplasts or cells have been accomplished in a few angiosperm genera. In gymnosperms all attempts to produce complete haploid plants have up to now failed. In this group there is possibly a relationship between polyembryonic seeds and the presence of small, haploid embryos. Therefore, the in vitro cultivation of small embryos of such seeds may result in the formation of independent haploid plants. In vitro cultivation of whole microsporangia or pollen has led to the production of calli in a few gymnosperm genera and in one case roots have even been induced. In some gymnosperms female gametophytes cultured on nutrient medium have yielded calli and in a few genera even root-like organs or small seedlings have arisen. (author)

  11. The role of sex chromosomes in mammalian germ cell differentiation: can the germ cells carrying X and Y chromosomes differentiate into fertile oocytes?

    Directory of Open Access Journals (Sweden)

    Teruko Taketo

    2015-06-01

    Full Text Available The sexual differentiation of germ cells into spermatozoa or oocytes is strictly regulated by their gonadal environment, testis or ovary, which is determined by the presence or absence of the Y chromosome, respectively. Hence, in normal mammalian development, male germ cells differentiate in the presence of X and Y chromosomes, and female germ cells do so in the presence of two X chromosomes. However, gonadal sex reversal occurs in humans as well as in other mammalian species, and the resultant XX males and XY females can lead healthy lives, except for a complete or partial loss of fertility. Germ cells carrying an abnormal set of sex chromosomes are efficiently eliminated by multilayered surveillance mechanisms in the testis, and also, though more variably, in the ovary. Studying the molecular basis for sex-specific responses to a set of sex chromosomes during gametogenesis will promote our understanding of meiotic processes contributing to the evolution of sex determining mechanisms. This review discusses the fate of germ cells carrying various sex chromosomal compositions in mouse models, the limitation of which may be overcome by recent successes in the differentiation of functional germ cells from embryonic stem cells under experimental conditions.

  12. RAB-like 2 has an essential role in male fertility, sperm intra-flagellar transport, and tail assembly.

    Directory of Open Access Journals (Sweden)

    Jennifer C Y Lo

    Full Text Available A significant percentage of young men are infertile and, for the majority, the underlying cause remains unknown. Male infertility is, however, frequently associated with defective sperm motility, wherein the sperm tail is a modified flagella/cilia. Conversely, a greater understanding of essential mechanisms involved in tail formation may offer contraceptive opportunities, or more broadly, therapeutic strategies for global cilia defects. Here we have identified Rab-like 2 (RABL2 as an essential requirement for sperm tail assembly and function. RABL2 is a member of a poorly characterized clade of the RAS GTPase superfamily. RABL2 is highly enriched within developing male germ cells, where it localizes to the mid-piece of the sperm tail. Lesser amounts of Rabl2 mRNA were observed in other tissues containing motile cilia. Using a co-immunoprecipitation approach and RABL2 affinity columns followed by immunochemistry, we demonstrated that within developing haploid germ cells RABL2 interacts with intra-flagella transport (IFT proteins and delivers a specific set of effector (cargo proteins, including key members of the glycolytic pathway, to the sperm tail. RABL2 binding to effector proteins is regulated by GTP. Perturbed RABL2 function, as exemplified by the Mot mouse line that contains a mutation in a critical protein-protein interaction domain, results in male sterility characterized by reduced sperm output, and sperm with aberrant motility and short tails. Our data demonstrate a novel function for the RABL protein family, an essential role for RABL2 in male fertility and a previously uncharacterised mechanism for protein delivery to the flagellum.

  13. Haploid Barley from the Intergeneric Cross Hordeum vulgare x Psathyrostachys fragilis

    DEFF Research Database (Denmark)

    Bothmer, Roland; Jacobsen, Niels; Bagger Jørgensen, Rikke

    1984-01-01

    The intergeneric hybrid Hordeum vulgare x Psathyrostachys fragilis was fairly easily obtained. During each growing season the intermediate, perennial hybrid yielded haploid tillers of H. vulgare. Late in one season few, hybrid tillers headed. The morphology, cytology and enzymatic patterns...

  14. High production of wheat double haploids via anther culture

    Directory of Open Access Journals (Sweden)

    Kondić-Šipka Ankica

    2007-01-01

    Full Text Available Androgenous and regeneration abilities of 14 randomly selected F1 hybrids of wheat (Triticum aestivum L. were analyzed. Anthers were grown in vitro on a modified Potato-2 inductive medium. The hybrid NS111-95/Ana had the highest average values for androgenous capacity (33% and callus yield (119%, while the hybrid NS 92-250/Tiha had the lowest values for these traits (9 and 21%, respectively. Seven genotypes (50% had a frequency of green plants relative to the number of isolated anthers of over 10%, with the highest frequency of 21.3% (NS111-95/Sremica. This hybrid produced 12.8 doubled haploid (DH lines per spike used for isolation. In the other genotypes, the number of produced DH lines per spike ranged from 1 (30­Sc.Smoc.88-89/Hays-2 to 11.2 (NS111-95/Ana. As half of the randomly selected genotypes exhibited high green plant regeneration ability and a high production of DH lines per spike, it can be concluded that in vitro anther culture can be successfully used in breeding programs for rapid production of homozygous wheat lines.

  15. Maximization of Markers Linked in Coupling for Tetraploid Potatoes via Monoparental Haploids

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    Annette M. Bartkiewicz

    2018-05-01

    Full Text Available Haploid potato populations derived from a single tetraploid donor constitute an efficient strategy to analyze markers segregating from a single donor genotype. Analysis of marker segregation in populations derived from crosses between polysomic tetraploids is complicated by a maximum of eight segregating alleles, multiple dosages of the markers and problems related to linkage analysis of marker segregation in repulsion. Here, we present data on two monoparental haploid populations generated by prickle pollination of two tetraploid cultivars with Solanum phureja and genotyped with the 12.8 k SolCAP single nucleotide polymorphism (SNP array. We show that in a population of monoparental haploids, the number of biallelic SNP markers segregating in linkage to loci from the tetraploid donor genotype is much larger than in putative crosses of this genotype to a diverse selection of 125 tetraploid cultivars. Although this strategy is more laborious than conventional breeding, the generation of haploid progeny for efficient marker analysis is straightforward if morphological markers and flow cytometry are utilized to select true haploid progeny. The level of introgressed fragments from S. phureja, the haploid inducer, is very low, supporting its suitability for genetic analysis. Mapping with single-dose markers allowed the analysis of quantitative trait loci (QTL for four phenotypic traits.

  16. In vitro germ cell differentiation from cynomolgus monkey embryonic stem cells.

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    Kaori Yamauchi

    Full Text Available BACKGROUND: Mouse embryonic stem (ES cells can differentiate into female and male germ cells in vitro. Primate ES cells can also differentiate into immature germ cells in vitro. However, little is known about the differentiation markers and culture conditions for in vitro germ cell differentiation from ES cells in primates. Monkey ES cells are thus considered to be a useful model to study primate gametogenesis in vitro. Therefore, in order to obtain further information on germ cell differentiation from primate ES cells, this study examined the ability of cynomolgus monkey ES cells to differentiate into germ cells in vitro. METHODS AND FINDINGS: To explore the differentiation markers for detecting germ cells differentiated from ES cells, the expression of various germ cell marker genes was examined in tissues and ES cells of the cynomolgus monkey (Macaca fascicularis. VASA is a valuable gene for the detection of germ cells differentiated from ES cells. An increase of VASA expression was observed when differentiation was induced in ES cells via embryoid body (EB formation. In addition, the expression of other germ cell markers, such as NANOS and PIWIL1 genes, was also up-regulated as the EB differentiation progressed. Immunocytochemistry identified the cells expressing stage-specific embryonic antigen (SSEA 1, OCT-4, and VASA proteins in the EBs. These cells were detected in the peripheral region of the EBs as specific cell populations, such as SSEA1-positive, OCT-4-positive cells, OCT-4-positive, VASA-positive cells, and OCT-4-negative, VASA-positive cells. Thereafter, the effect of mouse gonadal cell-conditioned medium and growth factors on germ cell differentiation from monkey ES cells was examined, and this revealed that the addition of BMP4 to differentiating ES cells increased the expression of SCP1, a meiotic marker gene. CONCLUSION: VASA is a valuable gene for the detection of germ cells differentiated from ES cells in monkeys, and the

  17. Light and electron microscopic analyses of Vasa expression in adult germ cells of the fish medaka.

    Science.gov (United States)

    Yuan, Yongming; Li, Mingyou; Hong, Yunhan

    2014-07-15

    Germ cells of diverse animal species have a unique membrane-less organelle called germ plasm (GP). GP is usually associated with mitochondria and contains RNA binding proteins and mRNAs of germ genes such as vasa. GP has been described as the mitochondrial cloud (MC), intermitochondrial cement (IC) and chromatoid body (CB). The mechanism underlying varying GP structures has remained incompletely understood. Here we report the analysis of GP through light and electron microscopy by using Vasa as a marker in adult male germ cells of the fish medaka (Oryzias latipes). Immunofluorescence light microscopy revealed germ cell-specific Vasa expression. Vasa is the most abundant in mitotic germ cells (oogonia and spermatogonia) and reduced in meiotic germ cells. Vasa in round spermatids exist as a spherical structure reminiscent of CB. Nanogold immunoelectron microscopy revealed subcellular Vasa redistribution in male germ cells. Vasa in spermatogonia concentrates in small areas of the cytoplasm and is surrounded by mitochondria, which is reminiscent of MC. Vasa is intermixed with mitochondria to form IC in primary spermatocytes, appears as the free cement (FC) via separation from mitochondria in secondary spermatocyte and becomes condensed in CB at the caudal pole of round spermatids. During spermatid morphogenesis, Vasa redistributes and forms a second CB that is a ring-like structure surrounding the dense fiber of the flagellum in the midpiece. These structures resemble those described for GP in various species. Thus, Vasa identifies GP and adopts varying structures via dynamic reorganization at different stages of germ cell development. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Gender differences in the induction of chromosomal aberrations and gene mutations in rodent germ cells

    International Nuclear Information System (INIS)

    Adler, Ilse-Dore; Carere, Angelo; Eichenlaub-Ritter, Ursula; Pacchierotti, Francesca

    2007-01-01

    Germ cell mutagenicity testing provides experimental data to quantify genetic risk for exposed human populations. The majority of tests are performed with exposure of males, and female data are relatively rare. The reason for this paucity lies in the differences between male and female germ cell biology. Male germ cells are produced throughout reproductive life and all developmental stages can be ascertained by appropriate breeding schemes. In contrast, the female germ cell pool is limited, meiosis begins during embryogenesis and oocytes are arrested over long periods of time until maturation processes start for small numbers of oocytes during the oestrus cycle in mature females. The literature data are reviewed to point out possible gender differences of germ cells to exogenous agents such as chemicals or ionizing radiation. From the limited information, it can be concluded that male germ cells are more sensitive than female germ cells to the induction of chromosomal aberrations and gene mutations. However, exceptions are described which shed doubt on the extrapolation of experimental data from male rodents to the genetic risk of the human population. Furthermore, the female genome may be more sensitive to mutation induction during peri-conceptional stages compared to the male genome of the zygote. With few exceptions, germ cell experiments have been carried out under high acute exposure to optimize the effects and to compensate for the limited sample size in animal experiments. Human exposure to environmental agents, on the other hand, is usually chronic and involves low doses. Under these conditions, gender differences may become apparent that have not been studied so far. Additionally, data are reviewed that suggest a false impression of safety when responses are negative under high acute exposure of male rodents while a mutational response is induced by low chronic exposure. The classical (morphological) germ cell mutation tests are not performed anymore

  19. Histological evidence of testicular dysgenesis in contralateral biopsies from 218 patients with testicular germ cell cancer

    DEFF Research Database (Denmark)

    Hoei-Hansen, Christina E; Holm, Mette; Rajpert-De Meyts, Ewa

    2003-01-01

    This study was prompted by a hypothesis that testicular germ cell cancer may be aetiologically linked to other male reproductive abnormalities as a part of the so-called 'testicular dysgenesis syndrome' (TDS). To corroborate the hypothesis of a common association of germ cell cancer with testicular...... dysgenesis, microscopic dysgenetic features were quantified in contralateral testicular biopsies in patients with a testicular germ cell tumour. Two hundred and eighty consecutive contralateral testicular biopsies from Danish patients with testicular cancer diagnosed in 1998-2001 were evaluated...... presenting with testicular germ cell neoplasms of the adolescent and young type. The findings therefore support the hypothesis that this cancer is part of a testicular dysgenesis syndrome. The presence of contralateral carcinoma in situ was higher in the present study than previously reported....

  20. A set of haploid strains available for genetic studies of Saccharomyces cerevisiae flor yeasts.

    Science.gov (United States)

    Coi, Anna Lisa; Legras, Jean-Luc; Zara, Giacomo; Dequin, Sylvie; Budroni, Marilena

    2016-09-01

    Flor yeasts of Saccharomyces cerevisiae have been extensively studied for biofilm formation, however the lack of specific haploid model strains has limited the application of genetic approaches such as gene knockout, allelic replacement and Quantitative Trait Locus mapping for the deciphering of the molecular basis of velum formation under biological ageing. The aim of this work was to construct a set of flor isogenic haploid strains easy to manipulate genetically. The analysis of the allelic variations at 12 minisatellite loci of 174 Saccharomyces cerevisiae strains allowed identifying three flor parental strains with different phylogenic positions. These strains were characterized for sporulation efficiency, growth on galactose, adherence to polystyrene, agar invasion, growth on wine and ability to develop a biofilm. Interestingly, the inability to grow on galactose was found associated with a frameshift in GAL4 gene that seems peculiar of flor strains. From these wild flor strains, isogenic haploid strains were constructed by deleting HO gene with a loxP-KanMX-loxP cassette followed by the removal of the kanamycin cassette. Haploid strains obtained were characterized for their phenotypic and genetic properties and compared with the parental strains. Preliminary results showed that the haploid strains represent new tools for genetic studies and breeding programs on biofilm formation. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Don Germán

    OpenAIRE

    Juan Luis Mejía

    1991-01-01

    El veranillo de San Juan hace soportable el mediodía. Los "chorros d'oro" inundan de amarillo los antejardines del Prado. Las golondrinas veraneras invaden, al atardecer, los alrededores de la Biblioteca Departamental. Los voceadores de la suerte del paseo Bolívar claman a los cuatro vientos el número que cambiará su destino . Pero algo falta definitivamente en esta Barranquilla. De alguna manera la ciudad ya no es la misma. Falta Don Germán.

  2. Don Germán

    Directory of Open Access Journals (Sweden)

    Juan Luis Mejía

    1991-01-01

    Full Text Available El veranillo de San Juan hace soportable el mediodía. Los "chorros d'oro" inundan de amarillo los antejardines del Prado. Las golondrinas veraneras invaden, al atardecer, los alrededores de la Biblioteca Departamental. Los voceadores de la suerte del paseo Bolívar claman a los cuatro vientos el número que cambiará su destino . Pero algo falta definitivamente en esta Barranquilla. De alguna manera la ciudad ya no es la misma. Falta Don Germán.

  3. Stopping the Spread of Germs at Home, Work and School

    Science.gov (United States)

    ... Pandemic Other Stopping the Spread of Germs at Home, Work & School Language: English (US) Español Recommend on Facebook ... everyone from getting germs or spreading germs at home, work, or school. Clean and disinfect surfaces or objects. ...

  4. Haploids in Conifer Species: Characterization and Chromosomal Integrity of a Maritime Pine Cell Line

    Directory of Open Access Journals (Sweden)

    José Antonio Cabezas

    2016-11-01

    Full Text Available Haploids are a valuable tool for genomic studies in higher plants, especially those with huge genome size and long juvenile periods, such as conifers. In these species, megagametophyte cultures have been widely used to obtain haploid callus and somatic embryogenic lines. One of the main problems associated with tissue culture is the potential genetic instability of the regenerants. Because of this, chromosomal stability of the callus and/or somatic embryos should also be assessed. To this end, chromosome counting, flow cytometry and genotyping using microsatellites have been reported. Here, we present an overview of the work done in conifers, with special emphasis on the production of a haploid cell line in maritime pine (Pinus pinaster L. and the use of a set of molecular markers, which includes Single Nucleotide Polymorphisms (SNPs and microsatellites or Single Sequence Repeats (SSRs, to validate chromosomal integrity confirming the presence of all chromosomic arms.

  5. Efficiency of anther culture technique in the production of wheat double haploids

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    Kondić-Špika Ankica Đ.

    2008-01-01

    Full Text Available The objective of the study was to investigate efficiency of anther culture in the production of spontaneous double haploids from randomly selected heterozygous genotypes of wheat (Triticum aestivum L.. Anthers of 20 F1 wheat combinations were grown in vitro on a modified Potato-2 medium. All of the examined genotypes have shown the ability to produce pollen calluses as well as to regenerate green plants. On average for the whole experiment material, 47.2 calluses were produced per 100 cultured anthers. The green plant regeneration ranged from 0.8 to 13.4 green plants per spike, with an overall mean of 5.8. From the total of 582 regenerated green plants, 47.9% (279 were spontaneous double haploids. The final average yield from the study was 2.8 double haploids per spike.

  6. Multiphoton microscopy imaging of developing tooth germs

    Directory of Open Access Journals (Sweden)

    Pei-Yu Pan

    2014-01-01

    Conclusion: In this study, a novel multiphoton microscopy database of images from developing tooth germs in mice was set up. We confirmed that multiphoton laser microscopy is a powerful tool for investigating the development of tooth germ and is worthy for further application in the study of tooth regeneration.

  7. Doubly uniparental inheritance of mitochondria as a model system for studying germ line formation.

    Directory of Open Access Journals (Sweden)

    Liliana Milani

    Full Text Available BACKGROUND: Doubly Uniparental Inheritance (DUI of mitochondria occurs when both mothers and fathers are capable of transmitting mitochondria to their offspring, in contrast to the typical Strictly Maternal Inheritance (SMI. DUI was found in some bivalve molluscs, in which two mitochondrial genomes are inherited, one through eggs, the other through sperm. During male embryo development, spermatozoon mitochondria aggregate in proximity of the first cleavage furrow and end up in the primordial germ cells, while they are dispersed in female embryos. METHODOLOGY/PRINCIPAL FINDINGS: We used MitoTracker, microtubule staining and transmission electron microscopy to examine the mechanisms of this unusual distribution of sperm mitochondria in the DUI species Ruditapes philippinarum. Our results suggest that in male embryos the midbody deriving from the mitotic spindle of the first division concurs in positioning the aggregate of sperm mitochondria. Furthermore, an immunocytochemical analysis showed that the germ line determinant Vasa segregates close to the first cleavage furrow. CONCLUSIONS/SIGNIFICANCE: In DUI male embryos, spermatozoon mitochondria aggregate in a stable area on the animal-vegetal axis: in organisms with spiral segmentation this zone is not involved in cleavage, so the aggregation is maintained. Moreover, sperm mitochondria reach the same embryonic area in which also germ plasm is transferred. In 2-blastomere embryos, the segregation of sperm mitochondria in the same region with Vasa suggests their contribution in male germ line formation. In DUI male embryos, M-type mitochondria must be recognized by egg factors to be actively transferred in the germ line, where they become dominant replacing the Balbiani body mitochondria. The typical features of germ line assembly point to a common biological mechanism shared by DUI and SMI organisms. Although the molecular dynamics of the segregation of sperm mitochondria in DUI species are unknown

  8. Oocyte formation by mitotically-active germ cells purified from ovaries of reproductive age women

    Science.gov (United States)

    White, Yvonne A. R.; Woods, Dori C.; Takai, Yasushi; Ishihara, Osamu; Seki, Hiroyuki; Tilly, Jonathan L.

    2012-01-01

    Germline stem cells that produce oocytes in vitro and fertilization-competent eggs in vivo have been identified in and isolated from adult mouse ovaries. Here we describe and validate a FACS-based protocol that can be used with adult mouse ovaries and human ovarian cortical tissue to purify rare mitotically-active cells that exhibit a gene expression profile consistent with primitive germ cells. Once established in vitro, these cells can be expanded for months and spontaneously generate 35–50 µm oocytes, as determined by morphology, gene expression and attainment of haploid (1n) status. Injection of the human germline cells, engineered to stably express GFP, into human ovarian cortical biopsies leads to formation of follicles containing GFP-positive oocytes 1–2 weeks after xenotransplantation into immunodeficient female mice. Thus, ovaries of reproductive-age women, like adult mice, possess rare mitotically-active germ cells that can be propagated in vitro as well as generate oocytes in vitro and in vivo. PMID:22366948

  9. Oocyte formation by mitotically active germ cells purified from ovaries of reproductive-age women.

    Science.gov (United States)

    White, Yvonne A R; Woods, Dori C; Takai, Yasushi; Ishihara, Osamu; Seki, Hiroyuki; Tilly, Jonathan L

    2012-02-26

    Germline stem cells that produce oocytes in vitro and fertilization-competent eggs in vivo have been identified in and isolated from adult mouse ovaries. Here we describe and validate a fluorescence-activated cell sorting-based protocol that can be used with adult mouse ovaries and human ovarian cortical tissue to purify rare mitotically active cells that have a gene expression profile that is consistent with primitive germ cells. Once established in vitro, these cells can be expanded for months and can spontaneously generate 35- to 50-μm oocytes, as determined by morphology, gene expression and haploid (1n) status. Injection of the human germline cells, engineered to stably express GFP, into human ovarian cortical biopsies leads to formation of follicles containing GFP-positive oocytes 1-2 weeks after xenotransplantation into immunodeficient female mice. Thus, ovaries of reproductive-age women, similar to adult mice, possess rare mitotically active germ cells that can be propagated in vitro as well as generate oocytes in vitro and in vivo.

  10. Baldness, acne and testicular germ cell tumors

    Science.gov (United States)

    Trabert, Britton; Sigurdson, Alice J.; Sweeney, Anne M.; Amato, Robert J.; Strom, Sara S.; McGlynn, Katherine A.

    2013-01-01

    Androgen levels during critical periods of testicular development may be involved in the etiology of testicular germ cell tumors (TGCT). We evaluated the roles of adolescent and early adult life correlates of androgen exposure and TGCT in a hospital-based case control study. TGCT cases (n=187) and controls (n=148), matched on age, race and state of residence, participated in the study. Unconditional logistic regression was used to estimate associations between TGCT and male pattern baldness, severe acne, markers of puberty onset and body size. Cases were significantly less likely to report hair loss than controls (OR, 0.6; 95% CI, 0.4, 1.0). Amount of hair loss, increasing age at onset and increasing rate of loss were all inversely associated with TGCT (rate of hair loss: p-trend=0.03; age at onset: p-trend=0.03; amount of hair loss: p-trend=0.01). History of severe acne was inversely associated with TGCT (OR, 0.5; 95% CI, 0.3, 0.9) and height was positively associated with TGCT (p-trend=0.02). Increased endogenous androgen levels during puberty and early adulthood may be associated with decreased risk of TGCT. Additional studies of endogenous hormone levels during puberty and early adult life are warranted, especially studies evaluating the role of androgen synthesis, metabolism and uptake. PMID:21128977

  11. Intracranial germ-cell tumors

    International Nuclear Information System (INIS)

    Baker, L.L.; Kollias, S.S.; Cogen, P.H.; Barkovich, A.J.

    1991-01-01

    This paper reports on the MR characteristics together with the clinical and histologic features of cerebral germ-cell tumors were investigated to augment data regarding this rare, diverse class of neoplasms. Germinomas were homogeneous or heterogeneous masses, predominantly isointense to normal brain on T1-weighted images, and hyperintense and heterogeneous on T2-weighted images; three showed adjacent brain edema. Enhancement was prominent, either homogeneous or heterogeneous. One had spinal drop metastases. Teratomas, more common in young patients, were more heterogeneous than germinomas on T1-weighted and T2-weighted images. Five showed hyper- and hypointense foci on T1-weighted images that corresponded to fat and calcium, respectively, at CT. Teratomas did not enhance or enhanced heterogeneously. Two had intratumoral hemorrhage; there were no metastases. Both patients with choriocarcinoma had hemorrhagic masses

  12. Radiosensitivity of mouse germ cells

    International Nuclear Information System (INIS)

    Matsuda, Yoichi; Takeuchi, Toyoko; Maemori, Mamiko; Seki, Naohiko; Tobari, Izuo

    1991-01-01

    To estimate radiosensitivity of mouse germ cells the analysis of chromosome aberrations was performed at diakinesis-metaphase I of spermatocytes and first-cleavage metaphase of one-cell embryos after exposure to radiations at various stages of primary spermatocytes and spermatids. The result provided evidence that there are two major types of DNA damage in X-irradiated sperm : (1) short-lived DNA lesions ; the lesions are subject to repair inhibition by agents added in G 1 , and are converted into chromosome-type aberrations during G 1 , and (2) long-lived DNA lesions ; the lesions persist until S phase and repair of the lesions is inhibited by caffeine, hydroxyurea and arabinofuranosyl cytosine in G 2 . The characteristic of X-ray damage induced in spermiogenic stage and repair mechanism for the damage in the fertilized egg were discussed comparing with the results with two chemicals, methyl methanesulfonate (MMS) and mitomycin C (MMC). (J.P.N.)

  13. A tortoiseshell male cat

    DEFF Research Database (Denmark)

    Pedersen, A. S.; Berg, Lise Charlotte; Almstrup, Kristian

    2014-01-01

    Tortoiseshell coat color is normally restricted to female cats due to X-linkage of the gene that encodes the orange coat color. Tortoiseshell male cats do, however, occur at a low frequency among tortoiseshell cats because of chromosome aberrations similar to the Klinefelter syndrome in man...... tissue from a tortoiseshell male cat referred to us. Chromosome analysis using RBA-banding consistently revealed a 39,XXY karyotype. Histological examinations of testis biopsies from this cat showed degeneration of the tubules, hyperplasia of the interstitial tissue, and complete loss of germ cells....... Immunostaining using anti-vimentin and anti-VASA (DDX4) showed that only Sertoli cells and no germ cells were observed in the testicular tubules. As no sign of spermatogenesis was detected, we conclude that this is a classic case of a sterile, male tortoiseshell cat with a 39,XXY chromosome complement. © 2013 S...

  14. In vitro selection of rape variants resistant to oxalic acid using haploid stem apexes

    International Nuclear Information System (INIS)

    Wang Yifei; Huang Jianhua; Lu Ruiju; Sun Yuefang; Zhou Runmei; Zhou Zhijiang; Xie Zhujie; Liu Chenghong

    2002-01-01

    Mutagenic treatment was made of the haploid stem apexes rape strain '9841' and '9885' with Pingyangmycin. As a result of positive selection with oxalic acid providing selection pressure, variants with significantly higher tolerance to oxalic acid than the original ones were obtained. 3 germplasm with significantly higher resistance to Sclerotinia sclerotiorum than cultivar Hu You 12 were selected from field test

  15. Germ Cell-less Promotes Centrosome Segregation to Induce Germ Cell Formation

    Directory of Open Access Journals (Sweden)

    Dorothy A. Lerit

    2017-01-01

    Full Text Available The primordial germ cells (PGCs specified during embryogenesis serve as progenitors to the adult germline stem cells. In Drosophila, the proper specification and formation of PGCs require both centrosomes and germ plasm, which contains the germline determinants. Centrosomes are microtubule (MT-organizing centers that ensure the faithful segregation of germ plasm into PGCs. To date, mechanisms that modulate centrosome behavior to engineer PGC development have remained elusive. Only one germ plasm component, Germ cell-less (Gcl, is known to play a role in PGC formation. Here, we show that Gcl engineers PGC formation by regulating centrosome dynamics. Loss of gcl leads to aberrant centrosome separation and elaboration of the astral MT network, resulting in inefficient germ plasm segregation and aborted PGC cellularization. Importantly, compromising centrosome separation alone is sufficient to mimic the gcl loss-of-function phenotypes. We conclude Gcl functions as a key regulator of centrosome separation required for proper PGC development.

  16. Epigenetic features of testicular germ cell tumours in relation to epigenetic characteristics of foetal germ cells

    DEFF Research Database (Denmark)

    Kristensen, Dina Graae; Skakkebæk, Niels E; Rajpert-De Meyts, Ewa

    2013-01-01

    in humans. However, the common precursor of testicular cancers- the carcinoma in situ (CIS) cell- is thought to be an arrested foetal germ cell. Therefore studies of CIS cells may leverage information on human foetal germ cell development and, in particular, when neoplastic transformation is initiated....... In this review, we will focus on current knowledge of the epigenetics of CIS cells and relate it to the epigenetic changes occurring in early developing germ cells of mice during specification, migration and colonization. We will focus on DNA methylation and some of the best studied histone modifications like H3...... event in the initiation of testicular germ cell cancer. Even though only sparse information is available on epigenetic cues in human foetal germ cells, these indicate that the developmental patterns differ from the findings in mice and emphasize the need for further studies of foetal germ cell...

  17. Survival and DNA repair in ultraviolet-irradiated haploid and diploid cultured frog cells

    International Nuclear Information System (INIS)

    Freed, J.J.; Hoess, R.H.; Angelosanto, F.A.; Massey, H.C. Jr.

    1979-01-01

    Survival and repair of DNA following ultraviolet (254-nm) radiation have been investigated in ICR 2A, a cultured cell line from haploid embryos of the grassfrog, Rana pipiens. Survival curves from cells recovering in the dark gave mean lethal dose value (D 0 ) in the range 1.5-1.7 Jm -2 for both haploid and diploid cell stocks. The only significant difference observed between haploids and diploids was in the extent of the shoulder at low fluence (Dsub(q)), the value for exponentially multiplying diploid cells (3.0 Jm -2 ) being higher than that found for haploids (1.2 Jm -2 ). Irradiation of cultures reversibly blocked in the G1 phase of the cell cycle gave survival-curve coefficients indistinguishable between haploids and diploids. Post-irradiation exposure to visible light restored colony-forming capacity and removed chromatographically estimated pyrimidine dimers from DNA at the same rates. After fluences killing 90% of the cells, complete restoration of survival was obtained after 60-min exposure to 500 foot-candles, indicating that in this range lethality is entirely photoreversible and therefore attributable to pyrimidine dimers in DNA. Dimer removal required illumination following ultraviolet exposure, intact cells and physiological temperature, implying that the photoreversal involved DNA photolyase activity. Excision-repair capacity was slight, since no loss of dimers could be detected chromoatographically during up to 48 h incubation in the dark and since autoradiographically detected 'unscheduled DNA synthesis' was limited to a 2-fold increase saturated at 10 Jm -2 . These properties make ICR 2A frog cells useful to explore how DNA-repair pathways influence mutant yield. (Auth.)

  18. Treatment Option Overview (Ovarian Germ Cell Tumors)

    Science.gov (United States)

    ... Germ Cell Tumors Treatment (PDQ®)–Patient Version Treatment Option Overview Go to Health Professional Version Key Points ... and restore) the body’s blood cells. New treatment options Combination chemotherapy (the use of more than one ...

  19. Treatment Option Overview (Extragonadal Germ Cell Tumors)

    Science.gov (United States)

    ... Cell Tumors Treatment Testicular Cancer Treatment Age and gender can affect the risk of extragonadal germ cell ... Headache. Change in bowel habits. Feeling very tired. Trouble walking. Trouble in seeing or moving the eyes. ...

  20. General Information about Extragonadal Germ Cell Tumors

    Science.gov (United States)

    ... Cell Tumors Treatment Testicular Cancer Treatment Age and gender can affect the risk of extragonadal germ cell ... Headache. Change in bowel habits. Feeling very tired. Trouble walking. Trouble in seeing or moving the eyes. ...

  1. Epigenetic reprogramming in the porcine germ line

    DEFF Research Database (Denmark)

    Matzen, Sara Maj Hyldig; Croxall, Nicola; Contreras, David A.

    2011-01-01

    BACKGROUND: Epigenetic reprogramming is critical for genome regulation during germ line development. Genome-wide demethylation in mouse primordial germ cells (PGC) is a unique reprogramming event essential for erasing epigenetic memory and preventing the transmission of epimutations to the next...... an increased proportion of cells in G2. CONCLUSIONS: Our study demonstrates that epigenetic reprogramming occurs in pig migratory and gonadal PGC, and establishes the window of time for the occurrence of these events. Reprogramming of histone H3K9me2 and H3K27me3 detected between E15-E21 precedes the dynamic...... DNA demethylation at imprinted loci and DNA repeats between E22-E42. Our findings demonstrate that major epigenetic reprogramming in the pig germ line follows the overall dynamics shown in mice, suggesting that epigenetic reprogramming of germ cells is conserved in mammals. A better understanding...

  2. Transcriptome analysis of functional differentiation between haploid and diploid cells of Emiliania huxleyi, a globally significant photosynthetic calcifying cell

    Science.gov (United States)

    2009-01-01

    Background Eukaryotes are classified as either haplontic, diplontic, or haplo-diplontic, depending on which ploidy levels undergo mitotic cell division in the life cycle. Emiliania huxleyi is one of the most abundant phytoplankton species in the ocean, playing an important role in global carbon fluxes, and represents haptophytes, an enigmatic group of unicellular organisms that diverged early in eukaryotic evolution. This species is haplo-diplontic. Little is known about the haploid cells, but they have been hypothesized to allow persistence of the species between the yearly blooms of diploid cells. We sequenced over 38,000 expressed sequence tags from haploid and diploid E. huxleyi normalized cDNA libraries to identify genes involved in important processes specific to each life phase (2N calcification or 1N motility), and to better understand the haploid phase of this prominent haplo-diplontic organism. Results The haploid and diploid transcriptomes showed a dramatic differentiation, with approximately 20% greater transcriptome richness in diploid cells than in haploid cells and only ≤ 50% of transcripts estimated to be common between the two phases. The major functional category of transcripts differentiating haploids included signal transduction and motility genes. Diploid-specific transcripts included Ca2+, H+, and HCO3- pumps. Potential factors differentiating the transcriptomes included haploid-specific Myb transcription factor homologs and an unusual diploid-specific histone H4 homolog. Conclusions This study permitted the identification of genes likely involved in diploid-specific biomineralization, haploid-specific motility, and transcriptional control. Greater transcriptome richness in diploid cells suggests they may be more versatile for exploiting a diversity of rich environments whereas haploid cells are intrinsically more streamlined. PMID:19832986

  3. Recombination difference between sexes: a role for haploid selection.

    Directory of Open Access Journals (Sweden)

    Thomas Lenormand

    2005-03-01

    Full Text Available Why the autosomal recombination rate differs between female and male meiosis in most species has been a genetic enigma since the early study of meiosis. Some hypotheses have been put forward to explain this widespread phenomenon and, up to now, only one fact has emerged clearly: In species in which meiosis is achiasmate in one sex, it is the heterogametic one. This pattern, known as the Haldane-Huxley rule, is thought to be a side effect, on autosomes, of the suppression of recombination between the sex chromosomes. However, this rule does not hold for heterochiasmate species (i.e., species in which recombination is present in both sexes but varies quantitatively between sexes and does not apply to species lacking sex chromosomes, such as hermaphroditic plants. In this paper, we show that in plants, heterochiasmy is due to a male-female difference in gametic selection and is not influenced by the presence of heteromorphic sex chromosomes. This finding provides strong empirical support in favour of a population genetic explanation for the evolution of heterochiasmy and, more broadly, for the evolution of sex and recombination.

  4. Germ-line origins of mutation in families with hemophilia B: The sex ratio varies with the type of mutation

    Energy Technology Data Exchange (ETDEWEB)

    Ketterling, R.P.; Vielhaber, E.; Bottema, C.D.K.; Schaid, D.J.; Sommer, S.S. (Mayo Clinic/Foundation, Rochester, MN (United States)); Cohen, M.P. (Vanderbilt Univ., Nashville, TN (United States)); Sexauer, C.L. (Children' s Hospital, Oklahoma City, OK (United States))

    1993-01-01

    Previous epidemiological and biochemical studies have generated conflicting estimates of the sex ratio of mutation. Direct genomic sequencing in combination with haplotype analysis extends previous analyses by allowing the precise mutation to be determined in a given family. From analysis of the factor IX gene of 260 consecutive families with hemophilia B, the authors report the germ-line origin of mutation in 25 families. When combined with 14 origins of mutation reported by others and with 4 origins previously reported by them, a total of 25 occur in the female germ line, and 18 occur in the male germ line. The excess of germ-line origins in females does not imply an overall excess mutation rate per base pair in the female germ line. Bayesian analysis of the data indicates that the sex ratio varies with the type of mutation. The aggregate of single-base substitutions shows a male predominance of germ-line mutations (P < .002). The maximum-likelihood estimate of the male predominance is 3.5-fold. Of the single-base substitutions, deletions display a sex ratio of unity. Analysis of the parental age at transmission of a new mutation suggests that germ-line mutations are associated with a small increase in parental age in females but little, if any, increase in males. Although direct genomic sequencing offers a general method for defining the origin of mutation in specific families, accurate estimates of the sex ratios of different mutational classes require large sample sizes and careful correction for multiple biases of ascertainment. The biases in the present data result in an underestimate of the enhancement of mutation in males. 62 refs., 1 fig., 5 tabs.

  5. Exposure to endocrine disruptor induces transgenerational epigenetic deregulation of microRNAs in primordial germ cells.

    Directory of Open Access Journals (Sweden)

    Miguel A Brieño-Enríquez

    Full Text Available In mammals, germ cell differentiation is initiated in the Primordial Germ Cells (PGCs during fetal development. Prenatal exposure to environmental toxicants such as endocrine disruptors may alter PGC differentiation, development of the male germline and induce transgenerational epigenetic disorders. The anti-androgenic compound vinclozolin represents a paradigmatic example of molecule causing transgenerational effects on germ cells. We performed prenatal exposure to vinclozolin in mice and analyzed the phenotypic and molecular changes in three successive generations. A reduction in the number of embryonic PGCs and increased rate of apoptotic cells along with decrease of fertility rate in adult males were observed in F1 to F3 generations. Blimp1 is a crucial regulator of PGC differentiation. We show that prenatal exposure to vinclozolin deregulates specific microRNAs in PGCs, such as miR-23b and miR-21, inducing disequilibrium in the Lin28/let-7/Blimp1 pathway in three successive generations of males. As determined by global maps of cytosine methylation, we found no evidence for prominent changes in DNA methylation in PGCs or mature sperm. Our data suggest that embryonic exposure to environmental endocrine disruptors induces transgenerational epigenetic deregulation of expression of microRNAs affecting key regulatory pathways of germ cells differentiation.

  6. Heterozygosity for a Bub1 mutation causes female-specific germ cell aneuploidy in mice

    Energy Technology Data Exchange (ETDEWEB)

    Leland, Shawn; Nagarajan, Prabakaran; Polyzos, Aris; Thomas, Sharon; Samaan, George; Donnell, Robert; Marchetti, Francesco; Venkatachalam, Sundaresan

    2009-06-24

    Aneuploidy, the most common chromosomal abnormality at birth and the main ascertained cause of pregnancy loss in humans, originates primarily from chromosome segregation errors during oogenesis. Here we report that heterozygosity for a mutation in the mitotic checkpoint kinase gene, Bub1, induces aneuploidy in female germ cells of mice, and that the effect increases with advancing maternal age. Analysis of Bub1 heterozygous oocytes showed that aneuploidy occurred primarily during the first meiotic division and involved premature sister chromatid separation. Furthermore, aneuploidy was inherited in zygotes and resulted in the loss of embryos after implantation. The incidence of aneuploidy in zygotes was sufficient to explain the reduced litter size in matings with Bub1 heterozygous females. No effects were seen in germ cells from heterozygous males. These findings show that Bub1 dysfunction is linked to inherited aneuploidy in female germ cells and may contribute to the maternal age-related increase in aneuploidy and pregnancy loss.

  7. Testicular germ cell tumors: Molecular genetic and clinicomorphological aspects

    Directory of Open Access Journals (Sweden)

    M. V. Nemtsova

    2015-03-01

    Full Text Available Testicular tumors are the most common form of solid cancer in young men. According to the 2004 WHO classification, testicular germ cell tumors (TGCT may present with different histological types. Embryonic cells of varying grade may be a source of TGCT and the occurrence of this type of tumors is directly related to the formation of a pool of male sex cells and gametogenesis. The paper gives information on mo- lecular stages for the process of formation of male sex cells in health, as well as ways of their impairments leading to TGCT. An investigation of the profiles of gene expression and the spectrum of molecular damages revealed genes responsible for a predisposition to the sporadic and hereditary forms of TGCT. The paper presents the current molecular genetic and clinicomorphological characteristics of TGCT. 

  8. New evidence for the origin of intracranial germ cell tumours from primordial germ cells

    DEFF Research Database (Denmark)

    Hoei-Hansen, C E; Sehested, A; Juhler, M

    2006-01-01

    that it is not required for the initiation of malignant germ cell transformation. The expression of genes associated with embryonic stem cell pluripotency in CNS germ cell tumours strongly suggests that these tumours are derived from cells that retain, at least partially, an embryonic stem cell-like phenotype, which...... germ cell tumours and analysed expression of a wide panel of stem cell-related proteins (C-KIT, OCT-3/4 (POU5F1), AP-2gamma (TFAP2C), and NANOG) and developmentally regulated germ cell-specific proteins (including MAGE-A4, NY-ESO-1, and TSPY). Expression at the protein level was analysed in 21 children...... and young adults with intracranial germinomas and non-germinomas, contributing to a careful description of these unusual tumours and adding to the understanding of pathogenesis. Stem cell related proteins were highly expressed in intracranial germ cell tumours, and many similarities were detected...

  9. Genetic dissection of mammalian ERAD through comparative haploid and CRISPR forward genetic screens

    DEFF Research Database (Denmark)

    Timms, Richard T.; Menzies, Sam A.; Tchasovnikarova, Iva A.

    2016-01-01

    The application of forward genetic screens to cultured human cells represents a powerful method to study gene function. The repurposing of the bacterial CRISPR/Cas9 system provides an effective method to disrupt gene function in mammalian cells, and has been applied to genome-wide screens. Here, we...... compare the efficacy of genome-wide CRISPR/Cas9-mediated forward genetic screens versus gene-trap mutagenesis screens in haploid human cells, which represent the existing ‘gold standard’ method. This head-to-head comparison aimed to identify genes required for the endoplasmic reticulum....../3-associated disulphide reductase. Genome-wide CRISPR/Cas9-mediated screens together with haploid genetic screens provide a powerful addition to the forward genetic toolbox....

  10. On the effect of certain mutations on the radiosensitivity of haploid and diploid yeast cells

    International Nuclear Information System (INIS)

    Sokurova, E.N.; Korogodin, V.I.

    1978-01-01

    Mutation ade 1-6 in haploid cell Saccharomyces cerevisiae increases half as much against radioresistance of cells. Diploid cells lacking in adenine, homozygous by ade 1-6 mutation, are nearly twice as radiosensitive as prototrophic cells. Hence ade 1-6 mutation increases radioresistance of haploid cells and decreases that of diplois. These changes in radioresistance are not connected with variations in the extrapolation number of survival curve, the ability of cells to recover from radiation damages upon cultivation in an innutrient medium, and with the inactivation form ratio. Lack of adenine influences the radioresistance of diploid yeast irrespective of whether it is or it is not affected by homo- or heterozygosity by the locus of mating type

  11. Influence of time of auxin application on wheat haploid embrio formation

    Directory of Open Access Journals (Sweden)

    Prodanović Slaven

    2005-01-01

    Full Text Available A hybrid interspecies zygote appears after crosses between wheat and maize Zygote derived after usual self-fertilization in wheat is dividing by mitotic divisions into embryo. However, interspecies zygote aborts soon. Auxin treatment is widely used to promote its development. Growth hormones auxins have stimulative ortoxic effects on plant tissue sin relation to its concentration and the time of application. In this paper the effect of time of auxin dicamba application on embryo in wheat x maize crosses was investigated. Chromosomes of pollen donor parent are eliminated quickly in cells of such embryos and they become haploid. It was concluded that for the production of haploid embryos the best time for auxin application is one day after pollination with maize.

  12. Cellular heredity in haploid cultures of somatic cells, March 1968-April 1981. Final report

    International Nuclear Information System (INIS)

    Freed, J.J.

    1982-03-01

    An account is given of the development and application to cell-culture genetics of unique haploid cell lines from frog embryo developed in this laboratory. Since 1968, the main aim of this project has been to develop the haploid cell system for studies of mutagenesis in culture, particularly by ultraviolet radiation. In the course of this work we isolated chromosomally stable cell lines, derived and characterized a number of variants, and adapted cell hybridization and other methods to this material. Particular emphasis was placed on ultraviolet photobiology, including studies of cell survival, mutagenesis, and pathways of repair of uv-damaged DNA. Although at present less widely used for genetic experiments than mammalian cell lines, the frog cells offer the advantages of authentic haploidy and a favorable repertory of DNA repair pathways for study of uv mutagenesis

  13. TOPAZ1, a novel germ cell-specific expressed gene conserved during evolution across vertebrates.

    Directory of Open Access Journals (Sweden)

    Adrienne Baillet

    Full Text Available BACKGROUND: We had previously reported that the Suppression Subtractive Hybridization (SSH approach was relevant for the isolation of new mammalian genes involved in oogenesis and early follicle development. Some of these transcripts might be potential new oocyte and granulosa cell markers. We have now characterized one of them, named TOPAZ1 for the Testis and Ovary-specific PAZ domain gene. PRINCIPAL FINDINGS: Sheep and mouse TOPAZ1 mRNA have 4,803 bp and 4,962 bp open reading frames (20 exons, respectively, and encode putative TOPAZ1 proteins containing 1,600 and 1653 amino acids. They possess PAZ and CCCH domains. In sheep, TOPAZ1 mRNA is preferentially expressed in females during fetal life with a peak during prophase I of meiosis, and in males during adulthood. In the mouse, Topaz1 is a germ cell-specific gene. TOPAZ1 protein is highly conserved in vertebrates and specifically expressed in mouse and sheep gonads. It is localized in the cytoplasm of germ cells from the sheep fetal ovary and mouse adult testis. CONCLUSIONS: We have identified a novel PAZ-domain protein that is abundantly expressed in the gonads during germ cell meiosis. The expression pattern of TOPAZ1, and its high degree of conservation, suggests that it may play an important role in germ cell development. Further characterization of TOPAZ1 may elucidate the mechanisms involved in gametogenesis, and particularly in the RNA silencing process in the germ line.

  14. Mutation induction in haploid yeast after split-dose radiation-exposure. Pt. 1

    International Nuclear Information System (INIS)

    Schenk, K.; Zoelzer, F.; Kiefer, J.

    1989-01-01

    Mutation induction was investigated in wild-type haploid yeast Saccharomyces cerevisiae after split-dose UV-irradiation. Cells were exposed to fractionated 254 nm-UV-doses separated by intervals from 0 to 6 h with incubation either on non-nutrient or nutrient agar between. The test parameter was resistance to canavanine. If modifications of sensitivity due to incubation are appropriately taken into account there is no change of mutation frequency. (orig.)

  15. Stimulating effect of gamma radiation on haploid wheat production through microscope over co-culture system

    International Nuclear Information System (INIS)

    Naseri, M.; Rahimi, M.; Faramarz, M.

    2004-01-01

    Haploid production focuses on low plant regeneration in some wheat genotypes. Haploid application gamma ray as an electromagnetic ray has ionizing properties which can produce ions when passing through biological matter. It can produce genetic variation therefore, is applied in crop and ornamental improvement to enhance agronomic traits. The most important changes caused by gamma radiation is in DNA structure existing in the nucleus of cell. The desirable agronomic changes then will be passed on through generations. Another property of gamma ray can be it's stimulating effect which is the aim in this investigation. Microspore-overy co-culture of wheat along with application of low doses of gamma radiation 2,3 and 4 Gy as absorbing doses were implemented with the aim to evaluate wheat haploid production. Modified Morashig and Skoog medium was used as induction medium and 190-2 medium for regeneration. Two winter and two spring wheat cultivars were used as genetic material. Low doses of gamma radiation simulated microspore cell division and produced more calli relative to non-irradiated microspores only in winter type wheats. In microspore overy co-culture, filtered microspores were centrifuged and then plated in Petri dishes containing MMS+500 mg/I glutamine with 25 overies

  16. Effects of gamma irradiation of pollen on parthenogenetic haploid production in muskmelon (Cucumis melo L.)

    International Nuclear Information System (INIS)

    Cuny, F.; Grotte, M.; Dumas de Vaulx, R.; Rieu, A.

    1993-01-01

    The effects of increasing gamma ray exposures on muskmelon pollen of the Védrantais genotype were evaluated after autofertilization and hybridization with the F1.G1 genotype. Regardless of doses of between 0.15 and 1.6 kGy, fruit set and number of seeds per fruit were comparable to those of the control. The pollen tube from pollen irradiated with up to 2.5 kGy grew in styles and reached the ovules. When pollen was cultivated in vitro, relatively high doses of irradiation (1.6 kGy) were needed to reduce the level of germination. Radiation-induced changes in the generative nucleus led to the formation of two chromosomally unbalanced sperm cells (as indicated by the appearance of morphological dimorphism) which induced parthenogenetic development of the egg to form a haploid embryo. Haploid embryo production by gamma-irradiated pollen was genotype dependent. For exposures of between 0.15 and 2.5 kGy, the production of embryos was the same, about 3.4%; a maximum of 70% of these embryos placed in a specific culture medium produced haploid plants. The ploidy of the plantlets in vitro was determined by flow cytometry. No aneuploidy was detected. All resulting plants exhibited normal phenotypes. (author) [fr

  17. Selection on Optimal Haploid Value Increases Genetic Gain and Preserves More Genetic Diversity Relative to Genomic Selection

    OpenAIRE

    Daetwyler, Hans D.; Hayden, Matthew J.; Spangenberg, German C.; Hayes, Ben J.

    2015-01-01

    Doubled haploids are routinely created and phenotypically selected in plant breeding programs to accelerate the breeding cycle. Genomic selection, which makes use of both phenotypes and genotypes, has been shown to further improve genetic gain through prediction of performance before or without phenotypic characterization of novel germplasm. Additional opportunities exist to combine genomic prediction methods with the creation of doubled haploids. Here we propose an extension to genomic selec...

  18. Establishment of the Vertebrate Germ Layers.

    Science.gov (United States)

    Tseng, Wei-Chia; Munisha, Mumingjiang; Gutierrez, Juan B; Dougan, Scott T

    2017-01-01

    The process of germ layer formation is a universal feature of animal development. The germ layers separate the cells that produce the internal organs and tissues from those that produce the nervous system and outer tissues. Their discovery in the early nineteenth century transformed embryology from a purely descriptive field into a rigorous scientific discipline, in which hypotheses could be tested by observation and experimentation. By systematically addressing the questions of how the germ layers are formed and how they generate overall body plan, scientists have made fundamental contributions to the fields of evolution, cell signaling, morphogenesis, and stem cell biology. At each step, this work was advanced by the development of innovative methods of observing cell behavior in vivo and in culture. Here, we take an historical approach to describe our current understanding of vertebrate germ layer formation as it relates to the long-standing questions of developmental biology. By comparing how germ layers form in distantly related vertebrate species, we find that highly conserved molecular pathways can be adapted to perform the same function in dramatically different embryonic environments.

  19. Study on the in vitro culture of cut plants in wheat haploid embryo induction by a wheat × maize cross

    Institute of Scientific and Technical Information of China (English)

    Jian GU; Kun LIU; Shaoxiang LI; Yuxian TIAN; Hexian YANG; Mujun YANG

    2008-01-01

    The wheat × maize system is one of the most effective ways to produce haploids in wheat. Whether and how it could be successfully applied in practical breeding mostly depends upon the efficiency of haploid embryo pro-duction. To perfect the protocols of haploid embryo induc-tion, the efficiency of haploid embryo production between in vitro culture of cut plant and intact plant growth for hybrid spikes with two F1 wheat hybrids and two maize varieties was compared. Effects of different cutting plant times and formulas of nutrient solutions for cut plant cul-ture on haploid embryo formation were also studied. Results indicated that the embryo rate of in vitro culture was 3.29 times that of intact plant growth, with the figures of 31.6% vs 9.6%, respectively. The optimal time for cut plant culture was 24 h after pollination. Formulas of nutri-ent solutions significantly affected the efficiency of haploid embryo induction. With an embryo rate of 0-35.5%, add-could raise the caryopsis and embryo rates. According to this study, the best medium for cut plant culture was: phate, with which a caryopsis rate of 95% and an embryo rate of about 30% could be obtained.

  20. Diploid, but not haploid, human embryonic stem cells can be derived from microsurgically repaired tripronuclear human zygotes

    Science.gov (United States)

    Fan, Yong; Li, Rong; Huang, Jin; Yu, Yang; Qiao, Jie

    2013-01-01

    Human embryonic stem cells have shown tremendous potential in regenerative medicine, and the recent progress in haploid embryonic stem cells provides new insights for future applications of embryonic stem cells. Disruption of normal fertilized embryos remains controversial; thus, the development of a new source for human embryonic stem cells is important for their usefulness. Here, we investigated the feasibility of haploid and diploid embryo reconstruction and embryonic stem cell derivation using microsurgically repaired tripronuclear human zygotes. Diploid and haploid zygotes were successfully reconstructed, but a large proportion of them still had a tripolar spindle assembly. The reconstructed embryos developed to the blastocyst stage, although the loss of chromosomes was observed in these zygotes. Finally, triploid and diploid human embryonic stem cells were derived from tripronuclear and reconstructed zygotes (from which only one pronucleus was removed), but haploid human embryonic stem cells were not successfully derived from the reconstructed zygotes when two pronuclei were removed. Both triploid and diploid human embryonic stem cells showed the general characteristics of human embryonic stem cells. These results indicate that the lower embryo quality resulting from abnormal spindle assembly contributed to the failure of the haploid embryonic stem cell derivation. However, the successful derivation of diploid embryonic stem cells demonstrated that microsurgical tripronuclear zygotes are an alternative source of human embryonic stem cells. In the future, improving spindle assembly will facilitate the application of triploid zygotes to the field of haploid embryonic stem cells. PMID:23255130

  1. Schrödinger’s Cheshire Cat: Are Haploid Emiliania huxleyi Cells Resistant to Viral Infection or Not?

    Directory of Open Access Journals (Sweden)

    Gideon J. Mordecai

    2017-03-01

    Full Text Available Emiliania huxleyi is the main calcite producer on Earth and is routinely infected by a virus (EhV; a double stranded DNA (dsDNA virus belonging to the family Phycodnaviridae. E. huxleyi exhibits a haplodiploid life cycle; the calcified diploid stage is non-motile and forms extensive blooms. The haploid phase is a non-calcified biflagellated cell bearing organic scales. Haploid cells are thought to resist infection, through a process deemed the “Cheshire Cat” escape strategy; however, a recent study detected the presence of viral lipids in the same haploid strain. Here we report on the application of an E. huxleyi CCMP1516 EhV-86 combined tiling array (TA that further confirms an EhV infection in the RCC1217 haploid strain, which grew without any signs of cell lysis. Reverse transcription polymerase chain reaction (RT-PCR and PCR verified the presence of viral RNA in the haploid cells, yet indicated an absence of viral DNA, respectively. These infected cells are an alternative stage of the virus life cycle deemed the haplococcolithovirocell. In this instance, the host is both resistant to and infected by EhV, i.e., the viral transcriptome is present in haploid cells whilst there is no evidence of viral lysis. This superimposed state is reminiscent of Schrödinger’s cat; of being simultaneously both dead and alive.

  2. Schrödinger's Cheshire Cat: Are Haploid Emiliania huxleyi Cells Resistant to Viral Infection or Not?

    Science.gov (United States)

    Mordecai, Gideon J; Verret, Frederic; Highfield, Andrea; Schroeder, Declan C

    2017-03-18

    Emiliania huxleyi is the main calcite producer on Earth and is routinely infected by a virus (EhV); a double stranded DNA (dsDNA) virus belonging to the family Phycodnaviridae . E. huxleyi exhibits a haplodiploid life cycle; the calcified diploid stage is non-motile and forms extensive blooms. The haploid phase is a non-calcified biflagellated cell bearing organic scales. Haploid cells are thought to resist infection, through a process deemed the "Cheshire Cat" escape strategy; however, a recent study detected the presence of viral lipids in the same haploid strain. Here we report on the application of an E. huxleyi CCMP1516 EhV-86 combined tiling array (TA) that further confirms an EhV infection in the RCC1217 haploid strain, which grew without any signs of cell lysis. Reverse transcription polymerase chain reaction (RT-PCR) and PCR verified the presence of viral RNA in the haploid cells, yet indicated an absence of viral DNA, respectively. These infected cells are an alternative stage of the virus life cycle deemed the haplococcolithovirocell. In this instance, the host is both resistant to and infected by EhV, i.e., the viral transcriptome is present in haploid cells whilst there is no evidence of viral lysis. This superimposed state is reminiscent of Schrödinger's cat; of being simultaneously both dead and alive.

  3. Schrödinger’s Cheshire Cat: Are Haploid Emiliania huxleyi Cells Resistant to Viral Infection or Not?

    Science.gov (United States)

    Mordecai, Gideon J.; Verret, Frederic; Highfield, Andrea; Schroeder, Declan C.

    2017-01-01

    Emiliania huxleyi is the main calcite producer on Earth and is routinely infected by a virus (EhV); a double stranded DNA (dsDNA) virus belonging to the family Phycodnaviridae. E. huxleyi exhibits a haplodiploid life cycle; the calcified diploid stage is non-motile and forms extensive blooms. The haploid phase is a non-calcified biflagellated cell bearing organic scales. Haploid cells are thought to resist infection, through a process deemed the “Cheshire Cat” escape strategy; however, a recent study detected the presence of viral lipids in the same haploid strain. Here we report on the application of an E. huxleyi CCMP1516 EhV-86 combined tiling array (TA) that further confirms an EhV infection in the RCC1217 haploid strain, which grew without any signs of cell lysis. Reverse transcription polymerase chain reaction (RT-PCR) and PCR verified the presence of viral RNA in the haploid cells, yet indicated an absence of viral DNA, respectively. These infected cells are an alternative stage of the virus life cycle deemed the haplococcolithovirocell. In this instance, the host is both resistant to and infected by EhV, i.e., the viral transcriptome is present in haploid cells whilst there is no evidence of viral lysis. This superimposed state is reminiscent of Schrödinger’s cat; of being simultaneously both dead and alive. PMID:28335465

  4. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 1: background to spermatogenesis, spermatogonia, and spermatocytes.

    Science.gov (United States)

    Hermo, Louis; Pelletier, R-Marc; Cyr, Daniel G; Smith, Charles E

    2010-04-01

    Spermatogenesis, a study of germ cell development, is a long, orderly, and well-defined process occurring in seminiferous tubules of the testis. It is a temporal event whereby undifferentiated spermatogonial germ cells evolve into maturing spermatozoa over a period of several weeks. Spermatogenesis is characterized by three specific functional phases: proliferation, meiosis, and differentiation, and it involves spermatogonia, spermatocytes, and spermatids. Germ cells at steps of development form various cellular associations or stages, with 6, 12, and 14 specific stages being identified in human, mouse, and rat, respectively. The stages evolve over time in a given area of the seminiferous tubule forming a cycle of the seminiferous epithelium that has a well-defined duration for a given species. In this part, we discuss the proliferation and meiotic phase whereby spermatogonia undergo several mitotic divisions to form spermatocytes that undergo two meiotic divisions to form haploid spermatids. In the rat, spermatogonia can be subdivided into several classes: stem cells (A(s)), proliferating cells (A(pr), A(al)), and differentiating cells (A(1)-A(4), In, B). They are dependent on a specific microenvironment (niche) contributed by Sertoli, myoid, and Leydig cells for proper development. Spermatogonia possess several surface markers whereby they can be identified from each other. During meiosis, spermatocytes undergo chromosomal pairing, synapsis, and genetic exchange as well as transforming into haploid cells following meiosis. The meiotic cells form specific structural entities such as the synaptonemal complex and sex body. Many genes involved in spermatogonial renewal and the meiotic process have been identified and shown to be essential for this event. Copyright 2009 Wiley-Liss, Inc.

  5. Application of Doubled Haploid (DH) Technique in Mutation and Conventional Wheat Breeding in Kenya

    International Nuclear Information System (INIS)

    Njau, P.N.

    2002-01-01

    Wheat is the second most important staple cereal in Kenya after maize.over the last six years wheat improvement for various stresses and agronomic characteristics have been undertaken through various biotechnological approaches which have been used as complements to the traditional breeding methods. The prime objective in any breeding program is the prevention of the debilitating effects of breeding. In self-pollinated crops such as wheat selection is more efficient homozygous lines than in segregating population. During repeated selfing, to develop homozygousity the vigour of the F1 of M1 plats is lost. Application of biotechnology in crop movement has been suggested as the useful tool in a faster variety development. The double haploid (DH) technique does not only shorten the time of developing homozygous lines but also maintains the heterosis of the F 1 , increase the selection of the efficiency of selection in mutants and increase the effectiveness of selection. in this study DHs were developed from F1 and M4 generation developed from drought tolerance.This was accomplished through the following step: (i)F 1 crosses were produced by crossing three drought tolerant varieties namely Kenya Mbweha, Duma and Ngamia with two highly yielding commercial varieties namely Kenya Chiriku and Kwale in 1998 while mutants were developed through gamma ray irradiation in 1995. (ii) The haploids were produced through chromosome elimination by crossing the F 1 s and the M 4 with maize pollen and (iii) the Double Haploid (DH) were produced by treating the haploid with colchicine. Twenty DH lines were produced from F 1 haploid and 5 from M 4 ones. The DH technique tend to increase uniformity, stability and distinctiveness of the mutants and the segregating populations. Most of the DHs showed wide variation indicating high potential of selection for various agronomic characteristics. Heterosis was realized on a number of characteristics in the DH lines. Through this technique the

  6. Radiotherapy of patients with germ cell tumor

    International Nuclear Information System (INIS)

    Inomata, Taisuke; Maeda, Tomoho; Yoshida, Shoji; Ogawa, Yasuhiro; Hamada, Fumio; Imajo, Yoshinari; Gose, Kyuhei; Fujiwara, Kiyoshi.

    1986-01-01

    Twenty-one patients with germ cell tumor who received radiotherapy were discussed. There were eight patients with germinoma, two patients with malignant teratoma, three patients with pineocytoma (out of category of germ cell tumor today) and eight unverified patients. Irradiated dose was mostly from 50 Gy to 60 Gy and local irradiation was performed after whole brain irradiation in many cases. The effect of radiotherapy was not so good in patients with malignant teratoma. On the contrary, it was relatively good in patients with germinoma and five out of eight patients are alive with no symptoms of recurrence. Six out of eight unverified patients are also alive. Among them, several patients with germinoma are considered to be included. Germinoma occupies many cases of germ cell tumor and has a good response to radiotherapy. Against spinal cord metastasis and late recurrence, additional therapy, such as chemotherapy, seems to be useful to improve cure ratio. (author)

  7. Non-germ cell tumours arising in germ cell tumours (teratoma with malignant transformation) in men: CT and MR findings

    Energy Technology Data Exchange (ETDEWEB)

    Athanasiou, A. [Department of Radiology, Institut Gustave-Roussy, Villejuif (France); Department of Radiology, Institut Curie, Paris (France)], E-mail: alexandra.athanasiou@curie.net; Vanel, D. [Department of Radiology, Institut Gustave-Roussy, Villejuif (France); Department of Radiology, Istituti Ortopedici Rizzoli, Bologna (Italy); El Mesbahi, O. [Department of Medicine, Institut Gustave-Roussy, Villejuif (France); Theodore, C. [Department of Medicine, Institut Gustave-Roussy, Villejuif (France); Department of Oncology, Hopital Foch, Suresnes (France); Fizazi, K. [Department of Medicine, Institut Gustave-Roussy, Villejuif (France)

    2009-02-15

    Purpose: To describe the imaging findings of germ cell tumours (GCT) containing non-germ cell malignant components (also designated teratoma with malignant transformation or TMT). Patients and methods: The records of 14 male patients with GCT and a non-germ cell histological component TMT were retrospectively reviewed. All patients had computed tomography (CT) and/or magnetic resonance (MR) studies before and after initial surgery and chemotherapy, as well as during follow-up. Imaging findings were correlated with the response to treatment and with overall survival. Pathological evaluation, immunohistochemistry, serum alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) were also taken into consideration. Sarcoma was identified in 10 out of 14 patients, with rhabdomyosarcoma ranking first (n = 4), followed by osteosarcoma (n = 2), fusiform cell sarcoma (n = 1), undifferentiated sarcoma (n = 1), neurosarcoma (n = 1) and myxoid sarcoma (n = 1). Other histological types of malignant transformation included adenocarcinoma (n = 3) and bronchoalveolar carcinoma (n = 1). Overall, 9 patients relapsed at a median time of 84 months (range 60-168). Results: Non-GCT malignant transformation was identified in the retroperitoneum (5), testis (3), mediastinum (3), peritoneum (2) and lungs (1). The CT and MR imaging findings before treatment and after relapse were evaluated with emphasis on imaging features that could possibly imply the presence of malignant transformation (heterogeneously enhancing soft-tissue masses, ossified masses with calcified lymph nodes, diffuse epiploic thickening associated with ascites and peritoneal nodules, pulmonary alveolar infiltration with septal thickening). All but 1 patient with TMT presented with nodal and distant metastases. The prognosis was poor: within a median follow-up of 59 months (range 3-180), 4 out of 14 patients were alive. Conclusion: TMT is rare and associated with poorer survival compared to GCT. Imaging can be useful

  8. Tooth-germ damage by ionizing radiation

    International Nuclear Information System (INIS)

    Sobkowiak, E.M.; Beetke, E.; Bienengraeber, V.; Held, M.; Kittner, K.H.

    1977-01-01

    Experiments on animals (four-week-old dogs) were conducted in an investigation made to study the possibility of dose-dependent tooth-germ damage produced by ionizing radiation. The individual doses were 50 R and 200 R, respectively, and they were administered once to three times at weekly intervals. Hyperemia and edemata could be observed on tooth-germ pulps from 150 R onward. Both of these conditions became more acute as the radiation dose increased (from 150 R to 600 R). Possible damage to both the dentin and enamel is pointed out. (author)

  9. Germ line mechanics – and unfinished business

    Science.gov (United States)

    Wessel, Gary M.

    2016-01-01

    Primordial germ cells are usually made early in the development of an organism. These are the mother of all stem cells that are necessary for propagation of the species, yet use highly diverse mechanisms between organisms. How they are specified, and when and where they form, are central to developmental biology. Using diverse organisms to study this development is illuminating for understanding the mechanics these cells use in this essential function, and for identifying the breadth of evolutionary changes that have occurred between species. This essay emphasizes how echinoderms may contribute to the patch-work quilt of our understanding of germ line formation during embryogenesis. PMID:26970000

  10. Human-specific subcellular compartmentalization of P-element induced wimpy testis-like (PIWIL) granules during germ cell development and spermatogenesis.

    Science.gov (United States)

    Gomes Fernandes, Maria; He, Nannan; Wang, Fang; Van Iperen, Liesbeth; Eguizabal, Cristina; Matorras, Roberto; Roelen, Bernard A J; Chuva De Sousa Lopes, Susana M

    2018-02-01

    What is the dynamics of expression of P-element induced wimpy testis-like (PIWIL) proteins in the germline during human fetal development and spermatogenesis? PIWIL1, PIWIL2, PIWIL3 and PIWIL4 were expressed in a sex-specific fashion in human germ cells (GC) during development and adulthood. PIWILs showed a mutually exclusive pattern of subcellular localization. PIWILs were present in the intermitochondrial cement and a single large granule in meiotic GC and their expression was different from that observed in mice, highlighting species-differences. In mice, PIWIL proteins play prominent roles in male infertility. PIWIL mouse mutants show either post-meiotic arrest at the round spermatid stage (PIWIL1) or arrest at the zygotene-pachytene stage of meiosis I (PIWIL2 and PIWIL4) in males, while females remain fertile. Recent studies have reported a robust piRNA pool in human fetal ovary. This is a qualitative analysis of PIWILs expression in paraffin-embedded fetal human male (N = 8), female gonads (N = 6) and adult testes (N = 5), and bioinformatics analysis of online available single-cell transcriptomics data of human fetal germ cells (n = 242). Human fetal gonads from elective abortion without medical indication and adult testes biopsies were donated for research with informed consent. Samples were fixed, paraffin-embedded and analyzed by immunofluorescence to study the temporal and cellular localization of PIWIL1, PIWIL2, PIWIL3 and PIWIL4. PIWIL1, PIWIL2 and PIWIL4 showed a mutually exclusive pattern of subcellular localization, particularly in female oocytes. To our surprise, PIWIL1 immunostaining revealed the presence of a single dense paranuclear body, resembling the chromatoid body of haploid spermatocytes, in meiotic oocytes. Moreover, in contrast to mice, PIWIL4, but not PIWIL2, localized to the intermitochondrial cement. PIWIL3 was not expressed in GC during development. The upregulation of PIWIL transcripts correlated with the transcription of markers

  11. Preliminary Study on Testicular Germ Cell Transplantation of Endemic Species Oryzias celebensis

    Science.gov (United States)

    Andriani, I.; Agustiani, F.; Hassan, M.; Parenrengi, A.; Inoue, K.

    2018-03-01

    The research has been conducted to study some technical steps for male germ-plasm from endemic fish species such as some species of Oryzias fish in Indonesia to preserve and propagate through germ cell transplantation technology. For preliminary research, the study was started with germ cell characterization of testes, cryopreservation of TGC and the transplantation of Oryzias celebensis as candidates for surrogate broodstock of Oryzias fish male germ plasm. The data analized included the potential number of TGC as donor, the viability of cryopreserved TGC in two types of cryoprotectans and the survival rate of O.celebensis larvae as recipient after transplantation. The result showed that the average amount of TGC yielded after dissociation was 131000 ± 31349 with 74.2 % viability of TGC each. Cryoprotectan10% DMSO +glucose yielded higher viable of TGC. More than 80 % of O.celebensis larvae survived after transplantation. In conclusion, these preliminary data of O.celebensis as surrogate broodstock candidate will support the application of TGC transplantation technology in Oryzias endemic species.

  12. Stability of wheat germ oil obtained by supercritical carbon dioxide ...

    African Journals Online (AJOL)

    심정은

    accumulated gas volume passing through the apparatus were measured using a gas flow meter. Wheat germ oil was ..... of rancidity in wheat germ analyzed by headspace gas chromatography and sensory analysis. J. Agric. Food Chem.

  13. Cross-talk between miR-471-5p and autophagy component proteins regulates LC3-associated phagocytosis (LAP) of apoptotic germ cells.

    Science.gov (United States)

    Panneerdoss, Subbarayalu; Viswanadhapalli, Suryavathi; Abdelfattah, Nourhan; Onyeagucha, Benjamin C; Timilsina, Santosh; Mohammad, Tabrez A; Chen, Yidong; Drake, Michael; Vuori, Kristiina; Kumar, T Rajendra; Rao, Manjeet K

    2017-09-19

    Phagocytic clearance of apoptotic germ cells by Sertoli cells is vital for germ cell development and differentiation. Here, using a tissue-specific miRNA transgenic mouse model, we show that interaction between miR-471-5p and autophagy member proteins regulates clearance of apoptotic germ cells via LC3-associated phagocytosis (LAP). Transgenic mice expressing miR-471-5p in Sertoli cells show increased germ cell apoptosis and compromised male fertility. Those effects are due to defective engulfment and impaired LAP-mediated clearance of apoptotic germ cells as miR-471-5p transgenic mice show lower levels of Dock180, LC3, Atg12, Becn1, Rab5 and Rubicon in Sertoli cells. Our results reveal that Dock180 interacts with autophagy member proteins to constitute a functional LC3-dependent phagocytic complex. We find that androgen regulates Sertoli cell phagocytosis by controlling expression of miR-471-5p and its target proteins. These findings suggest that recruitment of autophagy machinery is essential for efficient clearance of apoptotic germ cells by Sertoli cells using LAP.Although phagocytic clearance of apoptotic germ cells by Sertoli cells is essential for spermatogenesis, little of the mechanism is known. Here the authors show that Sertoli cells employ LC3-associated phagocytosis (LAP) by recruiting autophagy member proteins to clear apoptotic germ cells.

  14. Stages of Childhood Extracranial Germ Cell Tumors

    Science.gov (United States)

    ... tumors: Yolk sac tumors make a hormone called alpha-fetoprotein (AFP). They can form in the ovary, testicle, ... are used to detect extracranial germ cell tumors: Alpha-fetoprotein (AFP). Beta-human chorionic gonadotropin (β-hCG). For ...

  15. Linearization of germs of hyperbolic vector fields

    NARCIS (Netherlands)

    Bonckaert, P; Naudot, [No Value; Yang, JZ

    2003-01-01

    We develop a normal form to express asymptotically a conjugacy between a germ of resonant vector field and its linear part. We show that such an asymptotic expression can be written in terms of functions of the Logarithmic Mourtada type. To cite this article: P Bonckaert et al., C. R. Acad. Sci.

  16. A germ cell determinant reveals parallel pathways for germ line development in Caenorhabditis elegans.

    Science.gov (United States)

    Mainpal, Rana; Nance, Jeremy; Yanowitz, Judith L

    2015-10-15

    Despite the central importance of germ cells for transmission of genetic material, our understanding of the molecular programs that control primordial germ cell (PGC) specification and differentiation are limited. Here, we present findings that X chromosome NonDisjunction factor-1 (XND-1), known for its role in regulating meiotic crossover formation, is an early determinant of germ cell fates in Caenorhabditis elegans. xnd-1 mutant embryos display a novel 'one PGC' phenotype as a result of G2 cell cycle arrest of the P4 blastomere. Larvae and adults display smaller germ lines and reduced brood size consistent with a role for XND-1 in germ cell proliferation. Maternal XND-1 proteins are found in the P4 lineage and are exclusively localized to the nucleus in PGCs, Z2 and Z3. Zygotic XND-1 turns on shortly thereafter, at the ∼300-cell stage, making XND-1 the earliest zygotically expressed gene in worm PGCs. Strikingly, a subset of xnd-1 mutants lack germ cells, a phenotype shared with nos-2, a member of the conserved Nanos family of germline determinants. We generated a nos-2 null allele and show that nos-2; xnd-1 double mutants display synthetic sterility. Further removal of nos-1 leads to almost complete sterility, with the vast majority of animals without germ cells. Sterility in xnd-1 mutants is correlated with an increase in transcriptional activation-associated histone modification and aberrant expression of somatic transgenes. Together, these data strongly suggest that xnd-1 defines a new branch for PGC development that functions redundantly with nos-2 and nos-1 to promote germline fates by maintaining transcriptional quiescence and regulating germ cell proliferation. © 2015. Published by The Company of Biologists Ltd.

  17. Genetically conditioned male sterility

    International Nuclear Information System (INIS)

    Gottschalk, W.

    1976-01-01

    A survey is given of two different types of genetically controlled male sterility in higher plants. 'Functional' male sterility is due to the action of mutated genes causing a misdifferentiation of the growing points in different specific ways. Under the influence of the genes of this group either the stamens or the archespore tissues are not differentiated. In other mutants functionable male germ cells are produced but cannot be used for fertilizing the egg cells because the anthers remain closed or anthers and stigma become spatially separated from each other. Other genes of the group are responsible for the transformation of stamens into carpels, i.e. for a change of the hermaphrodite flower into a unisexually female one. A second type of male sterility is due to the action of ms genes influencing the course of micro-sporogenesis directly. They cause the breakdown of this process in a specific meiotic stage characteristic for each gene of the group. This breakdown is introduced by the degeneration of PMCs, microspores, or pollen grains preventing the production of male germ cells. The female sex organs remain uninfluenced. (author)

  18. TOXICOLOGY OF MALE REPRODUCTIVE DEVELOPMENT: PROFILING 774 CHEMICALS FOR MOLECULAR TARGETS AND ADVERSE OUTCOMES (SOT)

    Science.gov (United States)

    Adverse trends in male reproductive health have been reported for increased rates of testicular germ cell tumor, low semen quality, cryptorchidism, and hypospadias. An association with prenatal environmental exposure has been inferred from human and animal studies underlying male...

  19. Response of haploid and diploid protoplasts from Datura innoxia Mill. and Petunia hybrida L. to treatment with X-rays and a chemical mutagen

    International Nuclear Information System (INIS)

    Krumbiegel, G.

    1979-01-01

    Haploid and diploid protoplasts of the two Solanaceous species Datura innoxia Mill. and Petunia Hybridia L., were exposed to two different mutagens, increased doses of X-rays and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). With both species the survival rates of haploid protoplasts decreased exponentially with increased doses of X-rays and increased concentrations of MNNG. Diploid protoplasts showed a higher resistance than haploids only at higher mutagen doses or concentrations. After the MNNG-treatment of haploid protoplasts from Datura innoxia, four mutants with altered pigment patterns were isolated. (author)

  20. Polyamine patterns in haploid and diploid tobacco tissues and in vitro cultures

    Directory of Open Access Journals (Sweden)

    Sílvia Bicudo Carone

    2010-04-01

    Full Text Available The aim of this work was to determine PAs levels in pith tissues and callus cultures from haploid and diploid tobacco plants, explanted from the apical and basal regions of the stem. These explants were cultured in an RM-64 medium supplied with IAA and kinetin, under light or in the dark, during successive subcultures. PAs levels followed a basipetal decrease in diploid and an increase in haploid, pith tissues. A similar pattern of total PAs (free + conjugated was observed for the callus of diploid and haploid plants maintained in the light, and for the haploid callus in the dark, whereas the diploid callus in the dark showed a constant increase in total PAs levels until the end of culture. The PA increase in the diploid callus in the dark was related to free Put levels increase. The ploidy status of the plants could express different PA gradients together with the plant pith and in vitro callus cultures.O objetivo deste trabalho foi determinar os níveis de PAs em tecidos de medula e cultura de calos de plantas haplóides e diplóides de tabaco, obtidas da região apical e basal do caule. Estes explantes foram cultivados em meio RM-64 suplementado com AIA e cinetina, na luz e no escuro, durante vários subcultivos. Nos tecidos medulares, os níveis de PAs apresentam um decréscimo basípeto em diplóides e um aumento em haplóides.Um padrão similar nos níveis de PAs totais (livres+ conjugadas foi observado em calos haplóides e diplóides mantidos na luz, e haplóides no escuro, enquanto os diplóides cultivados no escuro mostraram um aumento constante até o final do cultivo. O aumento no conteúdo de PAs nos calos diplóides no escuro, foi devido ao aumento do conteúdo de Put livre. Foi observado que a ploidia da planta pode expressar diferentes gradientes de PA ao longo do tecido medular e nas culturas de calos in vitro.

  1. Generation of genetically modified mice using CRISPR/Cas9 and haploid embryonic stem cell systems

    Directory of Open Access Journals (Sweden)

    Li-Fang JIN

    2016-07-01

    Full Text Available With the development of high-throughput sequencing technology in the post-genomic era, researchers have concentrated their efforts on elucidating the relationships between genes and their corresponding functions. Recently, important progress has been achieved in the generation of genetically modified mice based on CRISPR/Cas9 and haploid embryonic stem cell (haESC approaches, which provide new platforms for gene function analysis, human disease modeling, and gene therapy. Here, we review the CRISPR/Cas9 and haESC technology for the generation of genetically modified mice and discuss the key challenges in the application of these approaches.

  2. Metabolic engineering of a haploid strain derived from a triploid industrial yeast for producing cellulosic ethanol.

    Science.gov (United States)

    Kim, Soo Rin; Skerker, Jeffrey M; Kong, In Iok; Kim, Heejin; Maurer, Matthew J; Zhang, Guo-Chang; Peng, Dairong; Wei, Na; Arkin, Adam P; Jin, Yong-Su

    2017-03-01

    Many desired phenotypes for producing cellulosic biofuels are often observed in industrial Saccharomyces cerevisiae strains. However, many industrial yeast strains are polyploid and have low spore viability, making it difficult to use these strains for metabolic engineering applications. We selected the polyploid industrial strain S. cerevisiae ATCC 4124 exhibiting rapid glucose fermentation capability, high ethanol productivity, strong heat and inhibitor tolerance in order to construct an optimal yeast strain for producing cellulosic ethanol. Here, we focused on developing a general approach and high-throughput screening method to isolate stable haploid segregants derived from a polyploid parent, such as triploid ATCC 4124 with a poor spore viability. Specifically, we deleted the HO genes, performed random sporulation, and screened the resulting segregants based on growth rate, mating type, and ploidy. Only one stable haploid derivative (4124-S60) was isolated, while 14 other segregants with a stable mating type were aneuploid. The 4124-S60 strain inherited only a subset of desirable traits present in the parent strain, same as other aneuploids, suggesting that glucose fermentation and specific ethanol productivity are likely to be genetically complex traits and/or they might depend on ploidy. Nonetheless, the 4124-60 strain did inherit the ability to tolerate fermentation inhibitors. When additional genetic perturbations known to improve xylose fermentation were introduced into the 4124-60 strain, the resulting engineered strain (IIK1) was able to ferment a Miscanthus hydrolysate better than a previously engineered laboratory strain (SR8), built by making the same genetic changes. However, the IIK1 strain showed higher glycerol and xylitol yields than the SR8 strain. In order to decrease glycerol and xylitol production, an NADH-dependent acetate reduction pathway was introduced into the IIK1 strain. By consuming 2.4g/L of acetate, the resulting strain (IIK1A

  3. Differential developmental expression of transcription factors GATA-4 and GATA-6, their cofactor FOG-2 and downstream target genes in testicular carcinoma in situ and germ cell tumors

    DEFF Research Database (Denmark)

    Salonen, Jonna; Rajpert-De Meyts, E; Mannisto, Susanna

    2010-01-01

    Testicular germ cell cancer is the most common malignancy among young males. The pre-invasive precursor, carcinoma in situ testis (CIS), presumably originates from arrested and transformed fetal gonocytes. Given that GATA transcription factors have essential roles in embryonic and testicular deve...... development, we explored the expression of GATA-4, GATA-6, cofactor friend of GATA (FOG)-2, and downstream target genes during human testis development and addressed the question whether changes in this pathway may contribute to germ cell neoplasms....

  4. Immature germ cells in semen ? correlation with total sperm count and sperm motility

    OpenAIRE

    Patil, Priya S.; Humbarwadi, Rajendra S.; Patil, Ashalata D.; Gune, Anita R.

    2013-01-01

    Background: Current data regarding infertility suggests that male factor contributes up to 30% of the total cases of infertility. Semen analysis reveals the presence of spermatozoa as well as a number of non-sperm cells, presently being mentioned in routine semen report as "round cells" without further differentiating them into leucocytes or immature germ cells. Aim: The aim of this work was to study a simple, cost-effective, and convenient method for differentiating the round cells in se...

  5. Interspecific comparison of the effects of continuous ionizing radiation on the primitive mammalian stem germ cell

    International Nuclear Information System (INIS)

    Erickson, B.H.

    1978-01-01

    The response of the mammalian oocyte to radiation is characterized by wide interspecific differences, and results of preliminary assays suggest that this may be the case with the primitive stem germ cell. To test the validity of this observation and to define probable causes for the differences, prenatal mice, rats, and guinea pigs were irradiated continuously throughout gestation at rates of 1 and 3 rads per 23-hr day. Prenatal pigs were irradiated continuously for 108 days at a dose rate of 0.25 rad per 23-hr day. In all cases germ cells were enumerated in gonads excised either at birth or 6 days after birth. A dose rate of 0.25 rad/day reduced the germ-cell number in the male and female pig to 38 and 60% of control, respectively, and only 1 and 5% of the germ cells in the respective sexes survived a dose rate of 1 rad/day. Application of the single-hit multitarget model to all pig data yielded values for D 0 and n of 28 and 0.8, respectively, for the male and 27 and 3.2, respectively, for the female. Corresponding values for the male and female rat were 275 (D 0 ) and 0.3 (n) and 159 (D 0 ) and 0.8 (n), respectively. Both sexes of the pig were either sterilized or brought near sterility by a dose rate of 1 rad/day. In the case of the male rodent, however, this dose rate reduced germ-cell number to only 71% of control in the mouse, 50% of control in the rat, and 41% of control in the guinea pig. Ninety percent of the germ cells in the female rat survived a dose rate of 1 rad/day, as did 87% in the mouse and 71% in the guinea pig. When total dose was used as the basis of comparison, the pig remained the most sensitive species. Thus the differences among rodent species are not great when compared to the tremendous difference between the rodent and pig. When rodents are compared with pigs, the difference in the magnitude of the effect of continuous irradiation on the primitive stem cells of both sexes appears to be dependent on length of time at risk

  6. Temporal germ cell development strategy during continuous spermatogenesis within the montane lizard, Sceloporus bicanthalis (Squamata; Phrynosomatidae).

    Science.gov (United States)

    Gribbins, Kevin; Anzalone, Marla; Collier, Matthew; Granados-González, Gisela; Villagrán-Santa Cruz, Maricela; Hernández-Gallegos, Oswaldo

    2011-10-01

    Sceloporus bicanthalis is a viviparous lizard that lives at higher elevations in Mexico. Adult male S. bicanthalis were collected (n = 36) from the Nevado de Toluca, Mexico (elevation is 4200 m) during August to December, 2007 and January to July, 2008. Testes were extracted, fixed in Trumps, and dehydrated in a graded series of ethanol. Tissues were embedded, sectioned (2 μm), stained, and examined via a light microscope to determine the spermatogenic developmental strategy of S. bicanthalis. In all months examined, the testes were spermiogenically active; based on this, plus the presence of sperm in the lumina of seminiferous tubules, we inferred that S. bicanthalis had year-round or continuous spermatogenesis, unlike most reptiles that occupy a temperate or montane habitat. It was recently reported that seasonally breeding reptiles had a temporal germ cell development strategy similar to amphibians, where germ cells progress through spermatogenesis as a single population, which leads to a single spermiation event. This was much different than spatial development within the testis of other derived amniotes. We hypothesized that germ cell development was temporal in S. bicanthalis. Therefore, we wanted to determine whether reptiles that practice continuous spermatogenesis have a mammalian-like spatial germ cell development, which is different than the typical temperate reptile exhibiting a temporal development. In the present study, S. bicanthalis had a temporal development strategy, despite its continuous spermatogenic cycle, making them similar to tropical anoles. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. Depletion of endogenous germ cells in tree shrews in preparation for spermatogonial transplantation.

    Science.gov (United States)

    Liu, Tingting; Guo, Ying; Yan, Lanzhen; Sun, Bin; Zheng, Ping; Zhao, Xudong

    2017-09-01

    To achieve successful spermatogonial transplantation, endogenous germ cells must be depleted in recipient animals to allow donor germ cells to colonize efficiently. Busulfan is commonly used for the depletion of endogenous germ cells in recipient males. However, the optimal dose of busulfan is species-specific, and the optimal dose in tree shrews is yet to be determined. The current study aimed to determine the optimal dose of busulfan for effective suppression of endogenous spermatogenesis in tree shrews. Different doses (15, 20, 25, 30, 35, 40 and 45 mg/kg) of busulfan were injected into tree shrews intraperitoneally. Survival rates of the different treatment groups were calculated at 2 weeks and body weights were measured at 4, 6, 8, 10 and 28 weeks post-busulfan treatment. The testes were also removed and weighed at 4, 6, 8, 10 and 28 weeks post-treatment, and the cross and longitude diameters of the testes and diameters of the seminiferous tubules were measured and histologically evaluated. It was observed that there were no significant differences in the survival rates between the 15-35 mg/kg treatment groups and the control group (P>0.05), while the survival rate of the 40 mg/kg treatment group significantly decreased relative to the control group (Pendogenous germ cells in tree shrews. This dose led to maximum suppression of endogenous spermatogenesis while maintaining an acceptable survival rate of >50% of the lethal dose of busulfan for tree shrews.

  8. Protective role of wheat germ oil on some biochemical parameters in irradiated rats

    International Nuclear Information System (INIS)

    Atia, A.I.; Darwish, M.M.; Sallam, M.H.

    2006-01-01

    Wheat germ oil is an organic nutritionally rich vegetable oil. It is an excellent source of vitamin E and essential fatty acids (octacosanol, linoleic and linolenic). The study confirmed the beneficial role of the used anti-oxidation agents as recommended radio-protectors due to their ability of scavenging free radicals produced by ionizing radiation. The efficacy of daily oral treatment of rats with wheat germ oil (10 mg/ Kg body wt) for 15 days to control many of the damaging effects of ionizing radiation when male rats were subjected to fractionated 8 Gy (2 Gy day after day) of gamma irradiation were studied. Blood samples were collected from animals at 10 and 15 days after treatment and/or exposure. In blood, the data obtained revealed that, radiation exposure caused significant increases in levels of malondialdehyde (MDA), triacylglycerol (TG), total cholesterol (TC), low-density lipoproteins (LDL) and glucose at the 10th day. Meanwhile, significant reduction in contents of total protein, albumin, globulins, high-density lipoproteins (HDL), vitamin E and glucose were recorded at the 15th day. Also, the majority of these parameters were estimated in liver tissues. The results revealed that administration of the natural product wheat germ oil partially ameliorated the radiation-induced biochemical disturbances. These effects were explained in the light of the presumed different mechanisms of wheat germ oil actions

  9. The Bile Acid Nuclear Receptor FXRα Is a Critical Regulator of Mouse Germ Cell Fate

    Directory of Open Access Journals (Sweden)

    Emmanuelle Martinot

    2017-07-01

    Full Text Available Spermatogenesis is the process by which spermatozoa are generated from spermatogonia. This cell population is heterogeneous, with self-renewing spermatogonial stem cells (SSCs and progenitor spermatogonia that will continue on a path of differentiation. Only SSCs have the ability to regenerate and sustain spermatogenesis. This makes the testis a good model to investigate stem cell biology. The Farnesoid X Receptor alpha (FXRα was recently shown to be expressed in the testis. However, its global impact on germ cell homeostasis has not yet been studied. Here, using a phenotyping approach in Fxrα−/− mice, we describe unexpected roles of FXRα on germ cell physiology independent of its effects on somatic cells. FXRα helps establish and maintain an undifferentiated germ cell pool and in turn influences male fertility. FXRα regulates the expression of several pluripotency factors. Among these, in vitro approaches show that FXRα controls the expression of the pluripotency marker Lin28 in the germ cells.

  10. Apomixis and the problem of obtaining haploids and homozygote diploids in pear (Pyrus communis L.

    Directory of Open Access Journals (Sweden)

    Є. О. Долматов

    2013-02-01

    Full Text Available The article highlights results of research over simulative apomixes in pear and its utilization for obtaining haploids and homozygote diploids. It has been established that over 50% pear varieties with failed remote hybridization are capable of generating seeds of apomictic origin producing diploid plants. Genotypes displaying maximal inclination to apomixes have been singled out. Apomictic pear seedlings obtained from foreign pollination within the limits of the same combination are inherent in profound morphological diversity. Fruit-bearing apomicts originated from one and the same maternal plant differ to the same extent as hybrid seedlings of the same family. Genetic markers have enabled to establish that these are embryo sacs in which meiosis has completed that give rise to apomictic seeds. In vitro method as used for the purpose of increasing apomictic plants output has been illustrated. The greatest induction of apomictic shoots in vitro has been reached by alternation of BAP cytokinin at concentration of 1mg/l and 2 mg/l on the background of GA3 amounting to 1,5 mg/l. Grafting with shoots in vitro on non-sterile rootstocks of pear (Pyrus communis has increased the output of plants up to 80%. A cytological assessment of 9 apomictic samples is provided. The cytological analysis of samples of apomictic forms has certified the presence of simulative haploid parthenogenesis in pear.

  11. A Trichosporonales genome tree based on 27 haploid and three evolutionarily conserved 'natural' hybrid genomes.

    Science.gov (United States)

    Takashima, Masako; Sriswasdi, Sira; Manabe, Ri-Ichiroh; Ohkuma, Moriya; Sugita, Takashi; Iwasaki, Wataru

    2018-01-01

    To construct a backbone tree consisting of basidiomycetous yeasts, draft genome sequences from 25 species of Trichosporonales (Tremellomycetes, Basidiomycota) were generated. In addition to the hybrid genomes of Trichosporon coremiiforme and Trichosporon ovoides that we described previously, we identified an interspecies hybrid genome in Cutaneotrichosporon mucoides (formerly Trichosporon mucoides). This hybrid genome had a gene retention rate of ~55%, and its closest haploid relative was Cutaneotrichosporon dermatis. After constructing the C. mucoides subgenomes, we generated a phylogenetic tree using genome data from the 27 haploid species and the subgenome data from the three hybrid genome species. It was a high-quality tree with 100% bootstrap support for all of the branches. The genome-based tree provided superior resolution compared with previous multi-gene analyses. Although our backbone tree does not include all Trichosporonales genera (e.g. Cryptotrichosporon), it will be valuable for future analyses of genome data. Interest in interspecies hybrid fungal genomes has recently increased because they may provide a basis for new technologies. The three Trichosporonales hybrid genomes described in this study are different from well-characterized hybrid genomes (e.g. those of Saccharomyces pastorianus and Saccharomyces bayanus) because these hybridization events probably occurred in the distant evolutionary past. Hence, they will be useful for studying genome stability following hybridization and speciation events. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  12. Brewing characteristics of haploid strains isolated from sake yeast Kyokai No. 7.

    Science.gov (United States)

    Katou, Taku; Kitagaki, Hiroshi; Akao, Takeshi; Shimoi, Hitoshi

    2008-11-01

    Sake yeast exhibit various characteristics that make them more suitable for sake brewing compared to other yeast strains. Since sake yeast strains are Saccharomyces cerevisiae heterothallic diploid strains, it is likely that they have heterozygous alleles on homologous chromosomes (heterozygosity) due to spontaneous mutations. If this is the case, segregation of phenotypic traits in haploid strains after sporulation and concomitant meiosis of sake yeast strains would be expected to occur. To examine this hypothesis, we isolated 100 haploid strains from Kyokai No. 7 (K7), a typical sake yeast strain in Japan, and compared their brewing characteristics in small-scale sake-brewing tests. Analyses of the resultant sake samples showed a smooth and continuous distribution of analytical values for brewing characteristics, suggesting that K7 has multiple heterozygosities that affect brewing characteristics and that these heterozygous alleles do segregate after sporulation. Correlation and principal component analyses suggested that the analytical parameters could be classified into two groups, indicating fermentation ability and sake flavour. (c) 2008 John Wiley & Sons, Ltd.

  13. Qtl mapping of wheat doubled haploids for chlorophyll content and chlorophyll fluorescence kinetics under drought stress imposed at anthesis stage

    International Nuclear Information System (INIS)

    Ilyas, M.; Ilyas, N.; Arshad, M.; Kazi, A.G.

    2014-01-01

    Drought stress is one of the major environmental constraints to crop plants including wheat worldwide. Synthetic hexaploid can act as a vehicle for improving crop tolerance against biotic and abiotic stresses. Doubled haploid population consisting of one hundred and forty individuals derived from cross of Opata and SH223 was used in the present study to identify genomic regions associated with various quantitative attributes of physiological nature. Doubled haploid mapping population was phenotyped for chlorophyll content and chlorophyll fluorescence kinetics under control and drought stress imposed at anthesis stage. Genotyping of population was accomplished by utilizing two hundred and sixty one polymorphic Gaterslaben wheat microsatellites and Beltsville agriculture research center simple sequence repeats. Linkage map of doubled haploid population comprising of 19 linkage groups and covering map length of two thousands six hundred and twenty six (2626) cM was constructed using map maker software. Major and minor QTLs associated with quantitative traits were identified using QGene software. Major QTL for chlorophyll content (QTc.wwc-1B-S11) of doubled haploid mapping population under anthesis drought stress was mapped on chromosome 1B and explained 10.09 percent of phenotypic variation at LOD score of 5.5. Seven major and minor QTLs for PCFK of doubled haploids were identified on chromosome 1B, 7A and 7D under control and drought stress at anthesis stage. The identified QTLs are of prime importance for high resolution mapping in synthetic hexaploid wheat. Genomic synteny of doubled haploids was observed with rice chromosome 2, 4, 7 and maize chromosome 7 owing to occurrence of orthologous QTLs for chlorophyll content and chlorophyll fluorescence respectively. (author)

  14. Molecular biology of testicular germ cell tumors.

    Science.gov (United States)

    Gonzalez-Exposito, R; Merino, M; Aguayo, C

    2016-06-01

    Testicular germ cell tumors (TGCTs) are the most common solid tumors in young adult men. They constitute a unique pathology because of their embryonic and germ origin and their special behavior. Genetic predisposition, environmental factors involved in their development and genetic aberrations have been under study in many works throughout the last years trying to explain the susceptibility and the transformation mechanism of TGCTs. Despite the high rate of cure in this type of tumors because its particular sensitivity to cisplatin, there are tumors resistant to chemotherapy for which it is needed to find new therapies. In the present work, it has been carried out a literature review on the most important molecular aspects involved in the onset and development of such tumors, as well as a review of the major developments regarding prognostic factors, new prognostic biomarkers and the possibility of new targeted therapies.

  15. Diagnostic markers for germ cell neoplasms

    DEFF Research Database (Denmark)

    Rajpert-De Meyts, Ewa; Nielsen, John E; Skakkebaek, Niels E

    2015-01-01

    This concise review summarises tissue and serum markers useful for differential diagnosis of germ cell tumours (GCTs), with focus on the most common testicular GCTs (TGCTs). GCTs are characterised by phenotypic heterogeneity due to largely retained embryonic pluripotency and aberrant somatic diff...... of molecular markers, which allow specific diagnosis of various subtypes of GCT and are very useful for early detection at the precursor stage and for monitoring of patients during the follow-up....

  16. A role for Lin28 in primordial germ cell development and germ cell malignancy

    Science.gov (United States)

    West, Jason A.; Viswanathan, Srinivas R.; Yabuuchi, Akiko; Cunniff, Kerianne; Takeuchi, Ayumu; Park, In-Hyun; Sero, Julia E.; Zhu, Hao; Perez-Atayde, Antonio; Frazier, A. Lindsay; Surani, M. Azim; Daley, George Q.

    2009-01-01

    The rarity and inaccessibility of the earliest primordial germ cells (PGCs) in the mouse embryo thwarts efforts to investigate molecular mechanisms of germ cell specification. Stella marks the minute founder population of the germ lineage1,2. Here we differentiate mouse embryonic stem cells (ESCs) carrying a Stella transgenic reporter into putative PGCs in vitro. The Stella+ cells possess a transcriptional profile similar to embryo-derived PGCs, and like their counterparts in vivo, lose imprints in a time-dependent manner. Using inhibitory RNAs to screen candidate genes for effects on the development of Stella+ cells in vitro, we discovered that Lin28, a negative regulator of let-7 microRNA processing3-6, is essential for proper PGC development. We further show that Blimp1, a let-7 target and a master regulator of PGC specification7-9, can rescue the effect of Lin28-deficiency during PGC development, thereby establishing a mechanism of action for Lin28 during PGC specification. Over-expression of Lin28 promotes formation of Stella+ cells in vitro and PGCs in chimeric embryos, and is associated with human germ cell tumours. The differentiation of putative PGCs from ESCs in vitro recapitulates the early stages of gamete development in vivo, and provides an accessible system for discovering novel genes involved in germ cell development and malignancy. PMID:19578360

  17. Radiation Therapy of Suprasellar Germ Cell Tumors

    International Nuclear Information System (INIS)

    Park, Woo Yoon; Choi, Doo Ho; Choi, Eun Kyung; Kim, Il Han; Ha, Sung Whan; Park, Charn Il

    1988-01-01

    A retrospective study was performed on 15 patients with suprasellar germ cell tumors treated by megavoltage external beam irradiation between Feb. 1979 and Dec. 1985. Follow-up period of survivors was 30 to 91 months. Histologic diagnosis was obtained before radiation therapy in 10 patients (9 germinomas and 1 mixed). Five patients were treated without histologic verification. In 9 patients with biopsy-proven germinomas radiation therapy was delivered to the craniospinal axis in 6, to the whole brain in 3. In 5 patients with mixed germ cell tumor or elevated tumor marker, irradiation was delivered to the craniospinal axis in 2, to the whole brain in 2, and to the primary site only in 1. Total doses ranged from 5,000 to 5,500 cGy to the primary site, 3,000 to 4,400 cGy to the whole brain, and 1,300 to 3,000 cGy to the spine. In these 14, local tumor was controlled and primary or spinal failure was not observed. One patient without elevated tumor marker was treated to the whole brain, The tumor was not controlled and he had spinal recurrence. It is proven that radiation therapy is an effective treatment for suprasellar germ cell tumors. The neuroendocrinologic presentation, tumor marker status, early response to radiation measured on CT seem to be useful means for selecting patients for radiation therapy when tissue diagnosis is not available

  18. Understanding Mammalian Germ Line Development with In Vitro Models.

    Science.gov (United States)

    Martínez-Arroyo, Ana M; Míguez-Forján, Jose M; Remohí, Jose; Pellicer, Antonio; Medrano, Jose V

    2015-09-15

    Germ line development is crucial in organisms with sexual reproduction to complete their life cycle. In mammals, knowledge about germ line development is based mainly on the mouse model, in which genetic and epigenetic events are well described. However, little is known about how germ line development is orchestrated in humans, especially in the earliest stages. New findings derived from human in vitro models to obtain germ cells can shed light on these questions. This comprehensive review summarizes the current knowledge about mammalian germ line development, emphasizing the state of the art obtained from in vitro models for germ cell-like cell derivation. Current knowledge of the pluripotency cycle and germ cell specification has allowed different in vitro strategies to obtain germ cells with proven functionality in mouse models. Several reports during the last 10 years show that in vitro germ cell derivation with proven functionality to generate a healthy offspring is possible in mice. However, differences in the embryo development and pluripotency potential between human and mouse make it difficult to extrapolate these results. Further efforts on both human and mouse in vitro models to obtain germ cells from pluripotent stem cells may help to elucidate how human physiological events take place; therefore, therapeutic strategies can also be considered.

  19. Convergent evolution of germ granule nucleators: A hypothesis.

    Science.gov (United States)

    Kulkarni, Arpita; Extavour, Cassandra G

    2017-10-01

    Germ cells have been considered "the ultimate stem cell" because they alone, during normal development of sexually reproducing organisms, are able to give rise to all organismal cell types. Morphological descriptions of a specialized cytoplasm termed 'germ plasm' and associated electron dense ribonucleoprotein (RNP) structures called 'germ granules' within germ cells date back as early as the 1800s. Both germ plasm and germ granules are implicated in germ line specification across metazoans. However, at a molecular level, little is currently understood about the molecular mechanisms that assemble these entities in germ cells. The discovery that in some animals, the gene products of a small number of lineage-specific genes initiate the assembly (also termed nucleation) of germ granules and/or germ plasm is the first step towards facilitating a better understanding of these complex biological processes. Here, we draw on research spanning over 100years that supports the hypothesis that these nucleator genes may have evolved convergently, allowing them to perform analogous roles across animal lineages. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  20. Mutations that affect meiosis in male mice influence the dynamics of the mid-preleptotene and bouquet stages

    International Nuclear Information System (INIS)

    Liebe, B.; Petukhova, G.; Barchi, M.; Bellani, M.; Braselmann, H.; Nakano, T.; Pandita, T.K.; Jasin, M.; Fornace, A.; Meistrich, M.L.; Baarends, W.M.; Schimenti, J.; Lange, T. de; Keeney, S.; Camerini-Otero, R.D.; Scherthan, H.

    2006-01-01

    Meiosis pairs and segregates homologous chromosomes and thereby forms haploid germ cells to compensate the genome doubling at fertilization. Homologue pairing in many eukaryotic species depends on formation of DNA double strand breaks (DSBs) during early prophase I when telomeres begin to cluster at the nuclear periphery (bouquet stage). By fluorescence in situ hybridization criteria, we observe that mid-preleptotene and bouquet stage frequencies are altered in male mice deficient for proteins required for recombination, ubiquitin conjugation and telomere length control. The generally low frequencies of mid-preleptotene spermatocytes were significantly increased in male mice lacking recombination proteins SPO11, MEI1, MLH1, KU80, ubiquitin conjugating enzyme HR6B, and in mice with only one copy of the telomere length regulator Terf1. The bouquet stage was significantly enriched in Atm -/- , Spo11 -/- , Mei1 m1Jcs/m1Jcs , Mlh1 -/- , Terf1 +/- and Hr6b -/- spermatogenesis, but not in mice lacking recombination proteins DMC1 and HOP2, the non-homologous end-joining DNA repair factor KU80 and the ATM downstream effector GADD45a. Mice defective in spermiogenesis (Tnp1 -/- , Gmcl1 -/- , Asm -/- ) showed wild-type mid-preleptotene and bouquet frequencies. A low frequency of bouquet spermatocytes in Spo11 -/- Atm -/- spermatogenesis suggests that DSBs contribute to the Atm -/- -correlated bouquet stage exit defect. Insignificant changes of bouquet frequencies in mice with defects in early stages of DSB repair (Dmc1 -/- , Hop2 -/- ) suggest that there is an ATM-specific influence on bouquet stage duration. Altogether, it appears that several pathways influence telomere dynamics in mammalian meiosis

  1. Lipase inactivation in wheat germ by gamma irradiation

    International Nuclear Information System (INIS)

    Jha, Pankaj Kumar; Kudachikar, V.B.; Kumar, Sourav

    2013-01-01

    An attempt was made to improve the shelf life of wheat germ by optimizing processing conditions involving γ-irradiation. Studies were carried out to investigate the effect of γ-irradiation (0–30 kGy doses) on the chemical composition of wheat germ with respect to variation in moisture, total ash, crude fat, free fatty acid, protein and lipase activity. The results demonstrate that shelf stability of wheat germ was achieved by inactivation of lipase at doses of γ-irradiation greater than 12 kGy. - Highlights: Ø γ-irradiation was found to inactivate Lipase present in Wheat Germ. Ø The treatment did not result in significant changes in Total Ash, Moisture and Protein Content of Wheat Germ. Ø The irradiation at 30 kGy resulted in 31.2 % inactivation of Lipase in Wheat Germ

  2. Retinoic acid combined with spermatogonial stem cell conditions facilitate the generation of mouse germ-like cells

    DEFF Research Database (Denmark)

    Dong, Guoyi; Shang, Zhouchun; Liu, Longqi

    2017-01-01

    Spermatogenic lineage has been directly generated in spermatogonial stem cell (SSC) conditions from human pluripotent stem cells (PSCs). However, it remains unknown whether mouse embryonic stem cells (ESCs) can directly differentiate into advanced male germ cell lineage in the same conditions. Here......, we showed rather low efficiency of germ-like cell generation from mouse ESCs in SSC conditions. Interestingly, addition of retinoic acid (RA) into SSC conditions enabled efficient differentiation of mouse ESCs into germ-like cells, as shown by the activation of spermatogenesis-associated genes...... such as Mvh, Dazl, Prdm14, Stella, Scp1, Scp3, Stra8 and Rec8. In contrast, for cells cultured in control medium, the activation of the above genes barely occurred. In addition, RA with SSC conditions yielded colonies of Acrosin-expressing cells and the positive ratio reached a peak at day 6. Our work thus...

  3. Male gametogenesis without centrioles.

    Science.gov (United States)

    Riparbelli, Maria Giovanna; Callaini, Giuliano

    2011-01-15

    The orientation of the mitotic spindle plays a central role in specifying stem cell-renewal by enabling interaction of the daughter cells with external cues: the daughter cell closest to the hub region is instructed to self-renew, whereas the distal one starts to differentiate. Here, we have analyzed male gametogenesis in DSas-4 Drosophila mutants and we have reported that spindle alignment and asymmetric divisions are properly executed in male germline stem cells that lack centrioles. Spermatogonial divisions also correctly proceed in the absence of centrioles, giving rise to cysts of 16 primary spermatocytes. By contrast, abnormal meiotic spindles assemble in primary spermatocytes. These results point to different requirements for centrioles during male gametogenesis of Drosophila. Spindle formation during germ cell mitosis may be successfully supported by an acentrosomal pathway that is inadequate to warrant the proper execution of meiosis. Copyright © 2010 Elsevier Inc. All rights reserved.

  4. Germ Plasm Biogenesis--An Oskar-Centric Perspective.

    Science.gov (United States)

    Lehmann, Ruth

    2016-01-01

    Germ granules are the hallmark of all germ cells. These membrane-less, electron-dense structures were first observed over 100 years ago. Today, their role in regulating and processing transcripts critical for the establishment, maintenance, and protection of germ cells is well established, and pathways outlining the biochemical mechanisms and physical properties associated with their biogenesis are emerging. © 2016 Elsevier Inc. All rights reserved.

  5. Cigarette smoking during early pregnancy reduces the number of embryonic germ and somatic cells

    DEFF Research Database (Denmark)

    Mamsen, Linn; Lutterodt, M C; Andersen, Elisabeth Anne Wreford

    2010-01-01

    BACKGROUND: Cigarette smoking during pregnancy is associated with negative reproductive consequences for male fetuses in adult life such as reduced testicular volume and sperm concentration. The present study evaluates the number of germ and somatic cells present in human embryonic first-trimeste......BACKGROUND: Cigarette smoking during pregnancy is associated with negative reproductive consequences for male fetuses in adult life such as reduced testicular volume and sperm concentration. The present study evaluates the number of germ and somatic cells present in human embryonic first......-trimester gonads in relation to maternal smoking. METHODS: The study includes 24 human first-trimester testes, aged 37-68 days post-conception, obtained from women undergoing legal termination of pregnancy. A questionnaire was used to obtain information about smoking and drinking habits during pregnancy. Validated...... confounders such as alcohol and coffee consumption (P = 0.002). The number of germ cells in embryonic gonads, irrespective of gender, was also significantly reduced by 41% (95% CI 58-19%, P = 0.001) in exposed versus non-exposed embryonic gonads. CONCLUSIONS: Prenatal exposure to maternal cigarette smoke...

  6. Cellular heredity in haploid cultures of somatic cells. Annual progress report, March 1, 1975--March 31, 1976. [UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Freed, J.J.

    1976-01-01

    In experiments with haploid and diploid derivatives from the haploid frog embryo cell line ICR 2A, we have investigated aspects of cell survival, DNA repair and mutant induction after exposure to 254 nm radiation. Survival curves for haploid and diploid cells in random growth or blocked in the Gl phase of the cell cycle were determined; the survival data do not differ sufficiently to permit the use of such comparisons as an index of recessive lethal induction. Studies of the induction of thymine dimers in DNA indicated that the incidence of dimers in DNA from haploid and diploid cells is similar after exposure of the cells to equal doses of ultraviolet. The cells are capable of photoreversing dimers but appear to be deficient in excision repair. In an attempt to examine the effect of the permitted mode of DNA repair on the yield of mutations, we compared the incidence of ouabain-resistant variants among survivors of ultraviolet exposure and of ultraviolet exposure followed by photoreversal. Although the yield of resistant colonies was small, the data suggest that photoreversal lowers the yield of resistant colonies and thus that the induction of this phenotype is related to dimer persistence in DNA. We have also observed by fluorescence microscopy that an acridine mustard mutagen, ICR 191, is preferentially accumulated in cytoplasmic granules having the intracellular distribution pattern of lysosomes. This form of incorporation may be significant in the apparently non-genetic early toxicity of this compound observed in experiments with cultured cells.

  7. Cellular heredity in haploid cultures of somatic cells. Annual progress report, March 1, 1975--March 31, 1976

    International Nuclear Information System (INIS)

    Freed, J.J.

    1976-01-01

    In experiments with haploid and diploid derivatives from the haploid frog embryo cell line ICR 2A, we have investigated aspects of cell survival, DNA repair and mutant induction after exposure to 254 nm radiation. Survival curves for haploid and diploid cells in random growth or blocked in the Gl phase of the cell cycle were determined; the survival data do not differ sufficiently to permit the use of such comparisons as an index of recessive lethal induction. Studies of the induction of thymine dimers in DNA indicated that the incidence of dimers in DNA from haploid and diploid cells is similar after exposure of the cells to equal doses of ultraviolet. The cells are capable of photoreversing dimers but appear to be deficient in excision repair. In an attempt to examine the effect of the permitted mode of DNA repair on the yield of mutations, we compared the incidence of ouabain-resistant variants among survivors of ultraviolet exposure and of ultraviolet exposure followed by photoreversal. Although the yield of resistant colonies was small, the data suggest that photoreversal lowers the yield of resistant colonies and thus that the induction of this phenotype is related to dimer persistence in DNA. We have also observed by fluorescence microscopy that an acridine mustard mutagen, ICR 191, is preferentially accumulated in cytoplasmic granules having the intracellular distribution pattern of lysosomes. This form of incorporation may be significant in the apparently non-genetic early toxicity of this compound observed in experiments with cultured cells

  8. Inheritance patterns of the response to in vitro doubled haploid induction in perennial ryegrass (Lolium perenne L.)

    Czech Academy of Sciences Publication Activity Database

    Begheyn, R. F.; Roulund, N.; Vangsgaard, K.; Kopecký, David; Studer, B.

    2017-01-01

    Roč. 130, č. 3 (2017), s. 667-679 ISSN 0167-6857 Institutional support: RVO:61389030 Keywords : Androgenesis * Androgenic capacity * Anther culture * Doubled haploid (DH) * Perennial ryegrass (Lolium perenne L.) Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 2.002, year: 2016

  9. Quantitative trait loci mapping of heat tolerance in a doubled haploid population of broccoli using genotyping-by-sequencing

    Science.gov (United States)

    Broccoli is a cool weather vegetable crop with a vernalization requirement to initiate and maintain floral development. Breeding for heat tolerance in broccoli has the potential to both expand viable production areas and extend the growing season. A doubled haploid (DH) population of broccoli (Bras...

  10. Selection on Optimal Haploid Value Increases Genetic Gain and Preserves More Genetic Diversity Relative to Genomic Selection.

    Science.gov (United States)

    Daetwyler, Hans D; Hayden, Matthew J; Spangenberg, German C; Hayes, Ben J

    2015-08-01

    Doubled haploids are routinely created and phenotypically selected in plant breeding programs to accelerate the breeding cycle. Genomic selection, which makes use of both phenotypes and genotypes, has been shown to further improve genetic gain through prediction of performance before or without phenotypic characterization of novel germplasm. Additional opportunities exist to combine genomic prediction methods with the creation of doubled haploids. Here we propose an extension to genomic selection, optimal haploid value (OHV) selection, which predicts the best doubled haploid that can be produced from a segregating plant. This method focuses selection on the haplotype and optimizes the breeding program toward its end goal of generating an elite fixed line. We rigorously tested OHV selection breeding programs, using computer simulation, and show that it results in up to 0.6 standard deviations more genetic gain than genomic selection. At the same time, OHV selection preserved a substantially greater amount of genetic diversity in the population than genomic selection, which is important to achieve long-term genetic gain in breeding populations. Copyright © 2015 by the Genetics Society of America.

  11. Simple Meets Single: The Application of CRISPR/Cas9 in Haploid Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Zixi Yin

    2017-01-01

    Full Text Available The CRISPR/Cas9 system provides a powerful method for the genetic manipulation of the mammalian genome, allowing knockout of individual genes as well as the generation of genome-wide knockout cell libraries for genetic screening. However, the diploid status of most mammalian cells restricts the application of CRISPR/Cas9 in genetic screening. Mammalian haploid embryonic stem cells (haESCs have only one set of chromosomes per cell, avoiding the issue of heterozygous recessive mutations in diploid cells. Thus, the combination of haESCs and CRISPR/Cas9 facilitates the generation of genome-wide knockout cell libraries for genetic screening. Here, we review recent progress in CRISPR/Cas9 and haPSCs and discuss their applications in genetic screening.

  12. Analysis of QTLs Associated with the Rice Quality Related Gene by Double Haploid Populations

    Science.gov (United States)

    Lee, Gyu-Ho; Yun, Byung-Wook

    2014-01-01

    We investigated the growth characteristics and analyzed the physicochemical properties of a doubled haploid population derived from a cross between “Cheongcheong” and “Nagdong” to breed a rice variety that tastes good after cooking and to detect quantitative trait loci (QTLs) associated with the taste of cooked rice. The results showed that these compounds also represent a normal distribution. Correlation analysis of the amylose, protein, and lipid contents indicated that each compound is related to the taste of cooked rice. The QTLs related to amylose content were 4 QTLs, protein content was 2 QTLs, and lipid content was 2 QTLs. Four of the QTLs associated with amylose content were detected on chromosomes 7 and 11. The index of coincidence for the QTLs related to amylose, protein, and lipid content was 70%, respectively. These markers showing high percentage of coincidence can be useful to select desirable lines for rice breeding. PMID:25478566

  13. Analysis of QTLs Associated with the Rice Quality Related Gene by Double Haploid Populations

    Directory of Open Access Journals (Sweden)

    Gyu-Ho Lee

    2014-01-01

    Full Text Available We investigated the growth characteristics and analyzed the physicochemical properties of a doubled haploid population derived from a cross between “Cheongcheong” and “Nagdong” to breed a rice variety that tastes good after cooking and to detect quantitative trait loci (QTLs associated with the taste of cooked rice. The results showed that these compounds also represent a normal distribution. Correlation analysis of the amylose, protein, and lipid contents indicated that each compound is related to the taste of cooked rice. The QTLs related to amylose content were 4 QTLs, protein content was 2 QTLs, and lipid content was 2 QTLs. Four of the QTLs associated with amylose content were detected on chromosomes 7 and 11. The index of coincidence for the QTLs related to amylose, protein, and lipid content was 70%, respectively. These markers showing high percentage of coincidence can be useful to select desirable lines for rice breeding.

  14. Effect of gamma-radiations on haploid cultured cells of Datura innoxia

    International Nuclear Information System (INIS)

    Jain, R.K.; Maherchandani, N.; Sharma, D.R.; Chowdhury, V.K.

    1981-01-01

    The effects of gamma-radiations were studied in haploid cultured cells of Datura innoxia. Growth of callus cultures and shoot differentiation were stimulated at low doses (0.2 and 1.0 kR), while the higher dose (5.0 kR) was inhibitory. Root differentiation was observed only in cultures exposed to 1.0 kR dose. Enzyme activities of alpha-amylase, peroxidase, malate dehydrogenase and phosphatases, and the amounts of buffer extractable proteins were stimulated at 0.2 and 1.0 kR and inhibited at 5.0 kR. Mitotic index too decreased at 5.0 kR. Mean nuclear volume increased with increase in radiation dose, probably due to increased ploidy. (author)

  15. Construction and characterization of a yeast artificial chromosome library containing seven haploid human genome equivalents

    International Nuclear Information System (INIS)

    Albertsen, H.M.; Abderrahim, H.; Cann, H.M.; Dausset, J.; Le Paslier, D.; Cohen, D.

    1990-01-01

    Prior to constructing a library of yeast artificial chromosomes (YACs) containing very large human DNA fragments, the authors performed a series of preliminary experiments aimed at developing a suitable protocol. They found an inverse relationship between YAC insert size and transformation efficiency. Evidence of occasional rearrangement within YAC inserts was found resulting in clonally stable internal deletions or clonally unstable size variations. A protocol was developed for preparative electrophoretic enrichment of high molecular mass human DNA fragments from partial restriction digests and ligation with the YAC vector in agarose. A YAC library has been constructed from large fragments of DNA from an Epstein-Barr virus-transformed human lymphoblastoid cell line. The library presently contains 50,000 clones, 95% of which are greater than 250 kilobase pairs in size. The mean YAC size of the library, calculated from 132 randomly isolated clones, is 430 kilobase pairs. The library thus contains the equivalent of approximately seven haploid human genomes

  16. Sexual Fate Change of XX Germ Cells Caused by the Deletion of SMAD4 and STRA8 Independent of Somatic Sex Reprogramming.

    Directory of Open Access Journals (Sweden)

    Quan Wu

    2016-09-01

    Full Text Available The differential programming of sperm and eggs in gonads is a fundamental topic in reproductive biology. Although the sexual fate of germ cells is believed to be determined by signaling factors from sexually differentiated somatic cells in fetal gonads, the molecular mechanism that determines germ cell fate is poorly understood. Herein, we show that mothers against decapentaplegic homolog 4 (SMAD4 in germ cells is required for female-type differentiation. Germ cells in Smad4-deficient ovaries respond to retinoic acid signaling but fail to undergo meiotic prophase I, which coincides with the weaker expression of genes required for follicular formation, indicating that SMAD4 signaling is essential for oocyte differentiation and meiotic progression. Intriguingly, germline-specific deletion of Smad4 in Stra8-null female germ cells resulted in the up-regulation of genes required for male gonocyte differentiation, including Nanos2 and PLZF, suggesting the initiation of male-type differentiation in ovaries. Moreover, our transcriptome analyses of mutant ovaries revealed that the sex change phenotype is achieved without global gene expression changes in somatic cells. Our results demonstrate that SMAD4 and STRA8 are essential factors that regulate the female fate of germ cells.

  17. Sexual Fate Change of XX Germ Cells Caused by the Deletion of SMAD4 and STRA8 Independent of Somatic Sex Reprogramming

    Science.gov (United States)

    Wu, Quan; Fukuda, Kurumi; Kato, Yuzuru; Zhou, Zhi; Deng, Chu-Xia; Saga, Yumiko

    2016-01-01

    The differential programming of sperm and eggs in gonads is a fundamental topic in reproductive biology. Although the sexual fate of germ cells is believed to be determined by signaling factors from sexually differentiated somatic cells in fetal gonads, the molecular mechanism that determines germ cell fate is poorly understood. Herein, we show that mothers against decapentaplegic homolog 4 (SMAD4) in germ cells is required for female-type differentiation. Germ cells in Smad4-deficient ovaries respond to retinoic acid signaling but fail to undergo meiotic prophase I, which coincides with the weaker expression of genes required for follicular formation, indicating that SMAD4 signaling is essential for oocyte differentiation and meiotic progression. Intriguingly, germline-specific deletion of Smad4 in Stra8-null female germ cells resulted in the up-regulation of genes required for male gonocyte differentiation, including Nanos2 and PLZF, suggesting the initiation of male-type differentiation in ovaries. Moreover, our transcriptome analyses of mutant ovaries revealed that the sex change phenotype is achieved without global gene expression changes in somatic cells. Our results demonstrate that SMAD4 and STRA8 are essential factors that regulate the female fate of germ cells. PMID:27606421

  18. BAX-mediated cell death affects early germ cell loss and incidence of testicular teratomas in Dnd1(Ter/Ter) mice.

    Science.gov (United States)

    Cook, Matthew S; Coveney, Douglas; Batchvarov, Iordan; Nadeau, Joseph H; Capel, Blanche

    2009-04-15

    A homozygous nonsense mutation (Ter) in murine Dnd1 (Dnd1(Ter/Ter)) results in a significant early loss of primordial germ cells (PGCs) prior to colonization of the gonad in both sexes and all genetic backgrounds tested. The same mutation also leads to testicular teratomas only on the 129Sv/J background. Male mutants on other genetic backgrounds ultimately lose all PGCs with no incidence of teratoma formation. It is not clear how these PGCs are lost or what factors directly control the strain-specific phenotype variation. To determine the mechanism underlying early PGC loss we crossed Dnd1(Ter/Ter) embryos to a Bax-null background and found that germ cells were partially rescued. Surprisingly, on a mixed genetic background, rescued male germ cells also generated fully developed teratomas at a high rate. Double-mutant females on a mixed background did not develop teratomas, but were fertile and produced viable off-spring. However, when Dnd1(Ter/Ter) XX germ cells developed in a testicular environment they gave rise to the same neoplastic clusters as mutant XY germ cells in a testis. We conclude that BAX-mediated apoptosis plays a role in early germ cell loss and protects from testicular teratoma formation on a mixed genetic background.

  19. Cytokeratin expression in mouse lacrimal gland germ epithelium.

    Science.gov (United States)

    Hirayama, Masatoshi; Liu, Ying; Kawakita, Tetsuya; Shimmura, Shigeto; Tsubota, Kazuo

    2016-05-01

    The lacrimal gland secretes tear fluids that protect the ocular surface epithelium, and its dysfunction leads to dry eye disease (DED). The functional restoration of the lacrimal gland by engraftment of a bioengineered lacrimal gland using lacrimal gland germ epithelial cells has been proposed to cure DED in mice. Here, we investigate the expression profile of cytokeratins in the lacrimal gland germ epithelium to clarify their unique characteristics. We performed quantitative polymerase chain reaction (Q-PCR) and immunohistochemistry (IHC) analysis to clarify the expression profile of cytokeratin in the lacrimal gland germ epithelium. The mRNA expression of keratin (KRT) 5, KRT8, KRT14, KRT15, and KRT18 in the lacrimal gland germ epithelium was increased compared with that in mouse embryonic stem cells and the lacrimal gland germ mesenchyme, as analyzed by Q-PCR. The expression level of KRT15 increased in the transition from stem cells to lacrimal gland germ epithelium, then decreased as the lacrimal gland matured. IHC revealed that the expression set of these cytokeratins in the lacrimal gland germ epithelium was different from that in the adult lacrimal gland. The expression of KRT15 was observed in the lacrimal gland germ epithelium, and it segmentalized into some of the basal cells in the intercanulated duct in mature gland. We determined the expression profile of cytokeratins in the lacrimal gland epithelium, and identified KRT15 as a candidate unique cellular marker for the lacrimal gland germ epithelium. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Cellular heredity in haploid cultures of somatic cells. Comprehensive report, April 1975--June 1977

    International Nuclear Information System (INIS)

    Freed, J.J.

    1977-07-01

    This report reviews genetic studies carried out since 1975 on a haploid cultured cell line from frog embryos (ICR 2A). Although a single chromosome set would be expected to facilitate recovery of recessive mutants, experiments suggested that cell culture variants might arise through processes more complex than the selection of simple mutational changes. Therefore, the objectives of the work reported here have been to throw light on just how cell culture variants arise in this system. First, we have continued to characterize the ICR 2A line, with emphasis on stability of karyotype and DNA content. Second, we have studied in detail the origin of two classes of drug-resistant variants. Bromodeoxyuridine resistance of the thymidine deficiency type has been shown to arise through sequential loss of two forms of thymidine-phosphorylating enzyme; loss of the second form of enzyme is complex, suggesting that changes more complex than simple recessive mutations may be involved. Another form of resistance, in which tolerance of high levels of bromodeoxyuridine is found in cells that continue to express thymidine kinase, remains under study. Variants resistant to microtubule inhibitors were isolated. It was found that these haploid strains have properties distinguishing them from analogous resistant strains isolated from diploid mammalian cell cultures in other laboratories. In order to understand better how mutagens are involved in the origin of cell culture variants, we have examined the effect of different forms of DNA repair on the frequency of drug-resistant colonies induced by ultraviolet radiation. Preliminary experiments suggest that the frequency of such colonies is greater when repair takes place through (presumably error-prone) dark repair than when (error-free) photoreversal is allowed to occur. Such experiments can determine whether new phenotypes arise from alterations in DNA, and thus whether, in a broad sense, they are likely to be mutational in nature

  1. Cellular heredity in haploid cultures of somatic cells. Comprehensive report, April 1975--June 1977. [UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Freed, J.J.

    1977-07-01

    This report reviews genetic studies carried out since 1975 on a haploid cultured cell line from frog embryos (ICR 2A). Although a single chromosome set would be expected to facilitate recovery of recessive mutants, experiments suggested that cell culture variants might arise through processes more complex than the selection of simple mutational changes. Therefore, the objectives of the work reported here have been to throw light on just how cell culture variants arise in this system. First, we have continued to characterize the ICR 2A line, with emphasis on stability of karyotype and DNA content. Second, we have studied in detail the origin of two classes of drug-resistant variants. Bromodeoxyuridine resistance of the thymidine deficiency type has been shown to arise through sequential loss of two forms of thymidine-phosphorylating enzyme; loss of the second form of enzyme is complex, suggesting that changes more complex than simple recessive mutations may be involved. Another form of resistance, in which tolerance of high levels of bromodeoxyuridine is found in cells that continue to express thymidine kinase, remains under study. Variants resistant to microtubule inhibitors were isolated. It was found that these haploid strains have properties distinguishing them from analogous resistant strains isolated from diploid mammalian cell cultures in other laboratories. In order to understand better how mutagens are involved in the origin of cell culture variants, we have examined the effect of different forms of DNA repair on the frequency of drug-resistant colonies induced by ultraviolet radiation. Preliminary experiments suggest that the frequency of such colonies is greater when repair takes place through (presumably error-prone) dark repair than when (error-free) photoreversal is allowed to occur. Such experiments can determine whether new phenotypes arise from alterations in DNA, and thus whether, in a broad sense, they are likely to be mutational in nature.

  2. Germ Cell Origins of Posttraumatic Stress Disorder Risk: The Transgenerational Impact of Parental Stress Experience.

    Science.gov (United States)

    Rodgers, Ali B; Bale, Tracy L

    2015-09-01

    Altered stress reactivity is a predominant feature of posttraumatic stress disorder (PTSD) and may reflect disease vulnerability, increasing the probability that an individual will develop PTSD following trauma exposure. Environmental factors, particularly prior stress history, contribute to the developmental programming of the hypothalamic-pituitary-adrenal stress axis. Critically, the consequences of stress experiences are transgenerational, with parental stress exposure impacting stress reactivity and PTSD risk in subsequent generations. Potential molecular mechanisms underlying this transmission have been explored in rodent models that specifically examine the paternal lineage, identifying epigenetic signatures in male germ cells as possible substrates of transgenerational programming. Here, we review the role of these germ cell epigenetic marks, including posttranslational histone modifications, DNA methylation, and populations of small noncoding RNAs, in the development of offspring stress axis sensitivity and disease risk. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  3. Doubled haploid production from Spanish onion (Allium cepa L.) germplasm: embryogenesis induction, plant regeneration and chromosome doubling.

    Science.gov (United States)

    Fayos, Oreto; Vallés, María P; Garcés-Claver, Ana; Mallor, Cristina; Castillo, Ana M

    2015-01-01

    The use of doubled haploids in onion breeding is limited due to the low gynogenesis efficiency of this species. Gynogenesis capacity from Spanish germplasm, including the sweet cultivar Fuentes de Ebro, the highly pungent landrace BGHZ1354 and the two Valenciana type commercial varieties Recas and Rita, was evaluated and optimized in this study. The OH-1 population, characterized by a high gynogenesis induction, was used as control. Growing conditions of the donor plants were tested with a one-step protocol and field plants produced a slightly higher percentage of embryogenesis induction than growth chamber plants. A one-step protocol was compared with a two-step protocol for embryogenesis induction. Spanish germplasm produced a 2-3 times higher percentage of embryogenesis with the two-step protocol, Recas showing the highest percentage (2.09%) and Fuentes de Ebro the lowest (0.53%). These percentages were significantly lower than those from the OH-1 population, with an average of 15% independently of the protocol used. The effect of different containers on plant regeneration was tested using both protocols. The highest percentage of acclimated plants was obtained with the two-step protocol in combination with Eco2box (70%), whereas the lowest percentage was observed with glass tubes in the two protocols (20-23%). Different amiprofos-methyl (APM) treatments were applied to embryos for chromosome doubling. A similar number of doubled haploid plants were recovered with 25 or 50 μM APM in liquid medium. However, the application of 25 μM in solid medium for 24 h produced the highest number of doubled haploid plants. Somatic regeneration from flower buds of haploid and mixoploid plants proved to be a successful approach for chromosome doubling, since diploid plants were obtained from the four regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their gynogenesis

  4. Doubled haploid production from Spanish onion (Allium cepa L. germplasm: embryogenesis induction, plant regeneration and chromosome doubling

    Directory of Open Access Journals (Sweden)

    Oreto eFayos

    2015-05-01

    Full Text Available The use of doubled haploids in onion breeding is limited due to the low gynogenesis efficiency of this species. Gynogenesis capacity from Spanish germplasm, including the sweet cultivar Fuentes de Ebro, the highly pungent landrace BGHZ1354 and the two Valenciana type commercial varieties Recas and Rita, was evaluated and optimized in this study. The OH-1 population, characterized by a high gynogenesis induction, was used as control. Growing conditions of the donor plants were tested with a one-step protocol and field plants produced a slightly higher percentage of embryogenesis induction than growth chamber plants. A one-step protocol was compared with a two-step protocol for embryogenesis induction. Spanish germplasm produced a 2 to 3 times higher percentage of embryogenesis with the two-step protocol, Recas showing the highest percentage (2.09% and Fuentes de Ebro the lowest (0.53%. These percentages were significantly lower than those from the OH-1 population, with an average of 15% independently of the protocol used. The effect of different containers on plant regeneration was tested using both protocols. The highest percentage of acclimated plants was obtained with the two-step protocol in combination with Eco2box (70%, whereas the lowest percentage was observed with glass tubes in the two protocols (20-23%. Different amiprofos-methyl (APM treatments were applied to embryos for chromosome doubling. A similar number of doubled haploid plants were recovered with 25 or 50 µM APM in liquid medium. However, the application of 25 µM in solid medium for 24 h produced the highest number of doubled haploid plants. Somatic regeneration from flower buds of haploid and mixoploid plants proved to be a successful approach for chromosome doubling, since diploid plants were obtained from the 4 regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their

  5. Gene manipulation: churches against germ changes.

    Science.gov (United States)

    Budiansky, S

    An immediate ban on human genetic engineering that alters germ cells is called for in a resolution, written by activist Jeremy Rifkin, that was released last week over the signatures of 21 Catholic bishops, a broad spectrum of Protestant and Jewish religious leaders, and three scientists. The resolution takes a much harder line than was espoused by religious leaders in a letter to the now-defunct President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research. Several of the signers indicated that they did not fully agree with the resolution, but saw it as a good vehicle to encourage public discussion.

  6. Sex reversal in zebrafish fancl mutants is caused by Tp53-mediated germ cell apoptosis.

    Directory of Open Access Journals (Sweden)

    Adriana Rodríguez-Marí

    2010-07-01

    Full Text Available The molecular genetic mechanisms of sex determination are not known for most vertebrates, including zebrafish. We identified a mutation in the zebrafish fancl gene that causes homozygous mutants to develop as fertile males due to female-to-male sex reversal. Fancl is a member of the Fanconi Anemia/BRCA DNA repair pathway. Experiments showed that zebrafish fancl was expressed in developing germ cells in bipotential gonads at the critical time of sexual fate determination. Caspase-3 immunoassays revealed increased germ cell apoptosis in fancl mutants that compromised oocyte survival. In the absence of oocytes surviving through meiosis, somatic cells of mutant gonads did not maintain expression of the ovary gene cyp19a1a and did not down-regulate expression of the early testis gene amh; consequently, gonads masculinized and became testes. Remarkably, results showed that the introduction of a tp53 (p53 mutation into fancl mutants rescued the sex-reversal phenotype by reducing germ cell apoptosis and, thus, allowed fancl mutants to become fertile females. Our results show that Fancl function is not essential for spermatogonia and oogonia to become sperm or mature oocytes, but instead suggest that Fancl function is involved in the survival of developing oocytes through meiosis. This work reveals that Tp53-mediated germ cell apoptosis induces sex reversal after the mutation of a DNA-repair pathway gene by compromising the survival of oocytes and suggests the existence of an oocyte-derived signal that biases gonad fate towards the female developmental pathway and thereby controls zebrafish sex determination.

  7. Endogenous retrovirus sequences expressed in male mammalian ...

    African Journals Online (AJOL)

    In humans, one ERV family, human endogenous retrovirus- K (HERV-K) is abundantly expressed, and is associated with germ cell tumours, while ERV3 env is expressed in normal human testis. Conclusion: The expression of ERVs in male reproductive tissues suggests a possible role in normal and disease conditions ...

  8. Intestinal obstruction in germ-free dogs.

    Science.gov (United States)

    Heneghan, J B; Robinson, J W; Menge, H; Winistörfer, B

    1981-08-01

    Mechanical occlusions were created in the intestines of four germ-free dogs. At the time of the operation, a control loop of mid-intestine was perfused in vivo and then excised for examinations in vitro, which included the determination of the equilibrium uptake of phenylalanine and of beta-methyl-glucoside, the influx kinetics of phenylalanine and morphometric analysis of the mucosa by microdissection and stereological techniques. Seven days after establishment of the occlusion the abdomen was reopened, and loops above and below the occlusion were perfused, and then excised for the same tests in vitro. Unlike occluded loops of conventional dogs, the intestine of the germ-free animal above the occlusion does not secrete water and electrolytes into the lumen. Its transport properties in vitro do not differ from those of the control loop, and the morphometric analyses reveal only slight changes in villus structure. The loop below the obstruction undergoes marked atrophy, as has been observed in conventional dogs. The results suggest that the copious secretion that occurs above an intestinal obstruction in normal animals is due to the presence of an abundant bacterial population in the obstruction fluid.

  9. Primordial germ cells and amnion development in the avian embryo

    NARCIS (Netherlands)

    De Melo Bernardo, Ana

    2016-01-01

    Primordial germ cells (PGCs) are the progenitors of the gametes, responsible for transmitting genetic information from generation to generation. Although there is a long history of gamete biology research, there is still a lot to be learned about many of the mechanisms underlying germ cell

  10. Childhood Central Nervous System Germ Cell Tumors Treatment

    Science.gov (United States)

    ... make hormones. Yolk sac tumors make the hormone alpha-fetoprotein (AFP). Mixed germ cell tumors are made of ... used to diagnose some CNS germ cell tumors: Alpha-fetoprotein (AFP). Beta-human chorionic gonadotropin (β-hCG). Blood ...

  11. Is Tobacco Smoke a Germ-Cell Mutagen?

    Science.gov (United States)

    Although no international organization exists to declare whether an agent is a germ-cell mutagen, tobacco smoke may be a human germ-cell mutagen. In the mouse, tobacco smoke induces a significant increase in the mutation frequency at an expanded simple tandem repeat (ESTR) locus....

  12. Germ cell transplantation in an azoospermic Klinefelter bull.

    Science.gov (United States)

    Joerg, Hannes; Janett, Fredi; Schlatt, Stefan; Mueller, Simone; Graphodatskaya, Daria; Suwattana, Duangsmorn; Asai, Mika; Stranzinger, Gerald

    2003-12-01

    Germ cell transplantation is a technique that transfers donor testicular cells into recipient testes. A population of germ cells can colonize the recipient testis, initiate spermatogenesis, and produce sperm capable of fertilization. In the present study, a nonmosaic Klinefelter bull was used as a germ cell recipient. The donor cell suspension was introduced into the rete testis using ultrasound-guided puncture. A pulsatile administration of GnRH was performed to stimulate spermatogenesis. The molecular approach to detect donor cells was done by a quantitative polymerase chain reaction with allele discrimination based on a genetic mutation between donor and recipient. Therefore, a known genetic mutation, associated with coat-color phenotype, was used to calculate the ratio of donor to recipient cells in the biopsy specimens and ejaculates for 10 mo. After slaughtering, meiotic preparations were performed. The injected germ cells did not undergo spermatogenesis. Six months after germ cell transplantation, the donor cells were rejected, which indicates that the donor cells could not incorporate in the testis. The hormone stimulation showed that the testosterone-producing Leydig cells were functionally intact. Despite subfertility therapy, neither the recipient nor the donor cells underwent spermatogenesis. Therefore, nonmosaic Klinefelter bulls are not suitable as germ cell recipients. Future germ cell recipients in cattle could be mosaic Klinefelters, interspecies hybrids, bulls with Sertoli cell-only syndrome, or bulls with disrupted germ cell migration caused by RNA interference.

  13. Editorial Introduction [to Female Germ Cells: Biology and Genetic Risk

    Science.gov (United States)

    This is an editorial introduction to the special issue of utation Research, titled, emale Germ Cells: Biology and Genetic isk, which is an attempt to present a collection of papers that emphasize the distinct properties of female germ cells and their characteristic response to mu...

  14. Generation of juvenile rainbow trout derived from cryopreserved whole ovaries by intraperitoneal transplantation of ovarian germ cells.

    Science.gov (United States)

    Lee, Seungki; Katayama, Naoto; Yoshizaki, Goro

    2016-09-23

    Cryopreservation of fish sperm offers the practical applications in the selective breeding and biodiversity conservation. However, because of the lack of cryopreservation methods for fish eggs and embryos, maternally inherited cytoplasmic compartments cannot be successfully preserved. We previously developed an alternative method to derive functional eggs and sperm from cryopreserved whole testis by transplanting testicular cells into female and male recipients. However, if target fish had ovaries, the previous method employing male-derived germ cells would be ineffective. Here, we aimed to generate functional gametes from cryopreserved whole ovaries by transplanting ovarian germ cells into peritoneal cavity of sterile hatchlings. Cryopreservation conditions for rainbow trout ovaries (1.0 M DMSO, 0.1 M trehalose, and 10% egg yolk) were optimized by testing several different cryoprotective agents. Ovarian germ cells from thawed ovaries were intraperitoneally transplanted into allogeneic triploid hatchlings. Transplanted germ cells migrated toward and were incorporated into recipient gonads, where they underwent gametogenesis. Transplantation efficiency of ovarian germ cells remained stable after cryopreservation period up to 1185 days. Although all triploid recipients that did not undergo transplantation were functionally sterile, 5 of 25 female recipients and 7 of 25 male recipients reached sexual maturity at 2.5 years post-transplantation. Inseminating the resultant eggs and sperm generated viable offspring displaying the donor characteristics of orange body color, green fluorescence, and chromosome numbers. This method is thus a breakthrough tool for the conservation of endangered fish species that are crucial to cryopreserve the genetic resources of female fish. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 4: intercellular bridges, mitochondria, nuclear envelope, apoptosis, ubiquitination, membrane/voltage-gated channels, methylation/acetylation, and transcription factors.

    Science.gov (United States)

    Hermo, Louis; Pelletier, R-Marc; Cyr, Daniel G; Smith, Charles E

    2010-04-01

    As germ cells divide and differentiate from spermatogonia to spermatozoa, they share a number of structural and functional features that are common to all generations of germ cells and these features are discussed herein. Germ cells are linked to one another by large intercellular bridges which serve to move molecules and even large organelles from the cytoplasm of one cell to another. Mitochondria take on different shapes and features and topographical arrangements to accommodate their specific needs during spermatogenesis. The nuclear envelope and pore complex also undergo extensive modifications concomitant with the development of germ cell generations. Apoptosis is an event that is normally triggered by germ cells and involves many proteins. It occurs to limit the germ cell pool and acts as a quality control mechanism. The ubiquitin pathway comprises enzymes that ubiquitinate as well as deubiquitinate target proteins and this pathway is present and functional in germ cells. Germ cells express many proteins involved in water balance and pH control as well as voltage-gated ion channel movement. In the nucleus, proteins undergo epigenetic modifications which include methylation, acetylation, and phosphorylation, with each of these modifications signaling changes in chromatin structure. Germ cells contain specialized transcription complexes that coordinate the differentiation program of spermatogenesis, and there are many male germ cell-specific differences in the components of this machinery. All of the above features of germ cells will be discussed along with the specific proteins/genes and abnormalities to fertility related to each topic. Copyright 2009 Wiley-Liss, Inc.

  16. Germ cell toxicity: significance in genetic and fertility effects of radiation and chemicals

    International Nuclear Information System (INIS)

    Oakberg, E.F.

    1983-01-01

    The response of the male and female to radiation and chemicals is different. Any loss of oocytes in the female cannot be replaced, and if severe enough, will result in a shortening of the reproductive span. In the male, a temporary sterile period may be induced owing to destruction of the differentiating spermatogonia, but the stem cells are the most resistant spermatogonial type, are capable of repopulating the seminiferous epithelium, and fertility usually returns. The response of both the male and female changes with development of the embryonic to the adult gonad, and with differentiation and maturation in the adult. The primordial germ cells, early oocytes, and differentiating spermatogonia of the adult male are unusually sensitive to the cytotoxic action of noxious agents, but each agent elicits a specific response owing to the intricate biochemical and physiological changes associated with development and maturation of the gametes. The relationship of germ cell killing to fertility is direct, and long-term fertility effects can be predicted from histological analysis of the gonads. The relationship to genetic effects, on the other hand, is indirect, and acts primarily by limiting the cell stages available for testing, by affecting the distribution of mitotically active stem cells among the different stages of the mitotic cycle, and thereby, changing both the type and frequency of genetic effects observed. 100 references, 38 figures, 7 tables

  17. N-acetylcysteine protects against cadmium-induced germ cell apoptosis by inhibiting endoplasmic reticulum stress in testes.

    Science.gov (United States)

    Ji, Yan-Li; Wang, Hua; Zhang, Cheng; Zhang, Ying; Zhao, Mei; Chen, Yuan-Hua; Xu, De-Xiang

    2013-03-01

    Cadmium (Cd) is a reproductive toxicant that induces germ cell apoptosis in the testes. Previous studies have demonstrated that endoplasmic reticulum (ER) stress is involved in Cd-induced germ cell apoptosis. The aim of the present study was to investigate the effects of N-acetylcysteine (NAC), an antioxidant, on Cd-induced ER stress and germ cell apoptosis in the testes. Male CD-1 mice were intraperitoneally injected with CdCl2 (2.0 mg kg(-1)). As expected, acute Cd exposure induced germ cell apoptosis in the testes, as determined by terminal dUTP nick-end labelling (TUNEL). However, the administration of NAC alleviated Cd-induced germ cell apoptosis in the testes. Further analysis showed that NAC attenuated the Cd-induced upregulation of testicular glucose-regulated protein 78 (GRP78), an important ER molecular chaperone. Moreover, NAC inhibited the Cd-induced phosphorylation of testicular eukaryotic translation initiation factor 2α (eIF2α), a downstream target of the double-stranded RNA-activated kinase-like ER kinase (PERK) pathway. In addition, NAC blocked the Cd-induced activation of testicular X binding protein (XBP)-1, indicating that NAC attenuates the Cd-induced ER stress and the unfolded protein response (UPR). Interestingly, NAC almost completely prevented the Cd-induced elevation of C/EBP homologous protein (CHOP) and phosphorylation of c-Jun N-terminal kinase (JNK), two components of the ER stress-mediated apoptotic pathway. In conclusion, NAC protects against Cd-induced germ cell apoptosis by inhibiting endoplasmic reticulum stress in the testes.

  18. Exposure to Brefeldin A promotes initiation of meiosis in murine female germ cells.

    Science.gov (United States)

    Zhang, Lian-Jun; Chen, Bo; Feng, Xin-Lei; Ma, Hua-Gang; Sun, Li-Lan; Feng, Yan-Min; Liang, Gui-Jin; Cheng, Shun-Feng; Li, Lan; Shen, Wei

    2015-01-01

    In mammals, ontogenesis starts from a fusion of spermatozoon and oocyte, which are produced by reductive nuclear division of a diploid germ cell in a specialised but complex biological process known as meiosis. However, little is known about the mechanism of meiotic initiation in germ cells, although many factors may be responsible for meiosis both in male and female gonads. In this study, 11.5 days post coitum (dpc) female fetal mouse genital ridges were cultured in vitro with exposure to Brefeldin A (BFA) for 6h, and the changes in meiosis were detected. Synaptonemal-complex analysis implied that BFA played a positive role in meiosis initiation and this hypothesis was confirmed by quantitative PCR of meiosis-specific genes: stimulated by retinoic acid gene 8 (Stra8) and deleted in a zoospermia-like (DAZL). At the same time, mRNA expression of retinoic acid synthetase (Raldh2) and retinoic acid (RA) receptors increased in female gonads with in vitro exposure to BFA. Transplanting genital ridges treated with BFA into the kidney capsule of immunodeficient mice demonstrated that the development capacity of female germ cells was normal, while formation of primordial follicles was seen to be a result of accelerated meiosis after exposure to BFA. In conclusion, the study indicated that BFA stimulated meiosis initiation partly by RA signalling and then promoted the development of follicles.

  19. Esrp1 is a marker of mouse fetal germ cells and differentially expressed during spermatogenesis.

    Directory of Open Access Journals (Sweden)

    Shaghayegh Saeidi

    Full Text Available ESRP1 regulates alternative splicing, producing multiple transcripts from its target genes in epithelial tissues. It is upregulated during mesenchymal to epithelial transition associated with reprogramming of fibroblasts to iPS cells and has been linked to pluripotency. Mouse fetal germ cells are the founders of the adult gonadal lineages and we found that Esrp1 mRNA was expressed in both male and female germ cells but not in gonadal somatic cells at various stages of gonadal development (E12.5-E15.5. In the postnatal testis, Esrp1 mRNA was highly expressed in isolated cell preparations enriched for spermatogonia but expressed at lower levels in those enriched for pachytene spermatocytes and round spermatids. Co-labelling experiments with PLZF and c-KIT showed that ESRP1 was localized to nuclei of both Type A and B spermatogonia in a speckled pattern, but was not detected in SOX9+ somatic Sertoli cells. No co-localization with the nuclear speckle marker, SC35, which has been associated with post-transcriptional splicing, was observed, suggesting that ESRP1 may be associated with co-transcriptional splicing or have other functions. RNA interference mediated knockdown of Esrp1 expression in the seminoma-derived Tcam-2 cell line demonstrated that ESRP1 regulates alternative splicing of mRNAs in a non-epithelial cell germ cell tumour cell line.

  20. Mixed germ cell tumor of mediastinum/lung masquerading as hemangioma in fine needle biopsy

    Directory of Open Access Journals (Sweden)

    Rathna Nuti

    2013-01-01

    Full Text Available The histological predominance of one component in a germ cell tumor can lead to a mistaken diagnosis. Here, we describe a mediastinal teratoma with predominant vascular proliferation (>90% which on fine needle biopsy was diagnosed as a pulmonary hemangioma. Later, resection specimen revealed other components constituting ~4%, changing the diagnosis while illustrating theimportance of careful evaluation. A 37-year-old Caucasian male with shortness of breath, weight loss, and history of recently resolved pneumonia was diagnosed with hemangioma, after a computed tomography guided fine needle biopsy of a -16.3-cm mediastinal pulmonary mass revealed abundant benign vascular elements. Following tumor excision, ~94% of the sample exhibited predominant vascular elementsThe mass also exhibited rare focal areas of malignant epithelium in a reticular arrangement and undifferentiated pleomorphic cells associated with vascular invasion. These atypical epithelial cells were positive for CD30, pan CK, AFP, β-HCG and CD 117, thusprocuring a diagnosis of mediastinal mixed germ cell tumor. Although mixed germ cell tumors consist of various tissue types, diagnosis can be easily overlooked if one component dominates. Therefore, obtaining adequate representative neoplasm samples, and sectioning the samples thoroughly, searching for coexisting tissue types is critical for accurate diagnosis.

  1. The control of male fertility by spermatid-specific factors: searching for contraceptive targets from spermatozoon's head to tail

    Science.gov (United States)

    Chen, Su-Ren; Batool, Aalia; Wang, Yu-Qian; Hao, Xiao-Xia; Chang, Chawn-Shang; Cheng, C Yan; Liu, Yi-Xun

    2016-01-01

    Male infertility due to abnormal spermatozoa has been reported in both animals and humans, but its pathogenic causes, including genetic abnormalities, remain largely unknown. On the other hand, contraceptive options for men are limited, and a specific, reversible and safe method of male contraception has been a long-standing quest in medicine. Some progress has recently been made in exploring the effects of spermatid-specifical genetic factors in controlling male fertility. A comprehensive search of PubMed for articles and reviews published in English before July 2016 was carried out using the search terms ‘spermiogenesis failure', ‘globozoospermia', ‘spermatid-specific', ‘acrosome', ‘infertile', ‘manchette', ‘sperm connecting piece', ‘sperm annulus', ‘sperm ADAMs', ‘flagellar abnormalities', ‘sperm motility loss', ‘sperm ion exchanger' and ‘contraceptive targets'. Importantly, we have opted to focus on articles regarding spermatid-specific factors. Genetic studies to define the structure and physiology of sperm have shown that spermatozoa appear to be one of the most promising contraceptive targets. Here we summarize how these spermatid-specific factors regulate spermiogenesis and categorize them according to their localization and function from spermatid head to tail (e.g., acrosome, manchette, head-tail conjunction, annulus, principal piece of tail). In addition, we emphatically introduce small-molecule contraceptives, such as BRDT and PPP3CC/PPP3R2, which are currently being developed to target spermatogenic-specific proteins. We suggest that blocking the differentiation of haploid germ cells, which rarely affects early spermatogenic cell types and the testicular microenvironment, is a better choice than spermatogenic-specific proteins. The studies described here provide valuable information regarding the genetic and molecular defects causing male mouse infertility to improve our understanding of the importance of spermatid

  2. MRI of intracranial germ cell tumours

    International Nuclear Information System (INIS)

    Sumida, M.; Uozumi, T.; Kiya, K.; Mukada, K.; Arita, K.; Kurisu, K.; Sugiyama, K.; Onda, J.; Satoh, H.; Ikawa, F.; Migita, K.

    1995-01-01

    We reviewed MRI findings in proven intracranial germ cell tumours in 22 cases, 12 of whom received Gd-DTPA. On T1-weighted images, the signal intensity of the tumour parenchyma was moderately low in 19 cases and isointense in 3; on T2-weighted images, it was high in all cases. Regions of different intensity thought to be cysts were found in 17 (77 %): 7 of 12 patients with germinoma (58 %) and in all other cases. Of the 13 patients with pineal lesions T1-weighted sagittal images showed the aqueduct to be obstructed in 5, stenotic in 7 and normal in 1. Strong contrast enhancement was observed in all 12 cases. Of the 14 patients with suprasellar lesions, 5 were found to have an intrasellar extension, and in 3 of these, the normal pituitary gland, which could be distinguished from the tumour, was displaced anteriorly. Ten patients (45 %) had multiple lesions. (orig.)

  3. Tritium effects on germ cells and fertility

    International Nuclear Information System (INIS)

    Dobson, R.L.; Kwan, T.C.; Straume, T.

    1982-01-01

    Primordial oocytes in juvenile mice show acute gamma-ray LD 50 as low as 6 rad. This provides opportunities for determining dose-response relations at low doses and chronic exposure in the intact animal - conditions of particular interest for hazard evaluation. Examined in this way, 3 HOH in body water is found to kill murine oocytes exponentially with dose, the LD 50 level for chronic exposure being only 2μCi/ml (delivering 0.4 rad/day). At very low doses and dose rates, where comparisons between tritium and other radiations are of special significance for radiological protection, the RBE of tritium compared with 60 Co gamma radiation reaches approximately 3. Effects on murine fertility from tritium-induced oocyte loss have been quantified by reproductive capacity measurements. Chronic low-level exposure has been examined also in three primate species - squirrel, rhesus, and bonnet monkeys. In squirrel monkeys the ovarian germ-cell supply is 99% destroyed by the time of birth from prenatal exposure to body-water levels of 3 HOH (administered in maternal drinking water) of only 3 μCi/ml, the LD 50 level being 0.5 μCi/ml (giving 0.1 rad/day), one fourth that in mice. Though not completely ruled out, similar high sensitivity of female germ cells has not been found in macaques; and it probably does not occur in man. The exquisite radiosensitivity of primordial oocytes in mice is apparently due to vulnerability of the plasma membrane (or something of similar geometry and location), not DNA. Evidence for this comes from tritium data as well as neutron studies. Tritium administered as 3 HOH, and therefore generally distributed, is much more effective in killing murine oocytes than is tritium administered as 3 H-TdR, localized in the nucleus. This situation in the mouse may have implications for estimating radiation genetic risk in the human female

  4. Localization of early germ cells in a stony coral, Euphyllia ancora: potential implications for a germline stem cell system in coral gametogenesis

    Science.gov (United States)

    Shikina, Shinya; Chung, Yi-Jou; Wang, Hsiang-Ming; Chiu, Yi-Ling; Shao, Zih-Fang; Lee, Yan-Horn; Chang, Ching-Fong

    2015-06-01

    Most corals exhibit annual or multiple gametogenic cycles. Thus far, coral gametogenesis has been studied in many species and locations during the past three decades; however, currently, only a few papers exist that describe the origin of germ cells, such as germline stem cells (GSCs), which support the continuous production of gametes in every reproductive cycle. To address this issue, in this study, we focused on and identified piwi gene, which has been used as a marker of germline cells, including GSCs, in various metazoans, in a scleractinian coral, Euphyllia ancora. Reverse-transcription PCR and Western blotting analyses revealed that E. ancora piwi-like ( Eapiwi) is expressed in mesentery tissues where the sites of gametogenesis are located for both sexes. Immunohistochemistry with a specific antibody against Eapiwi revealed strong immunoreactivity in the spermatogonia in males and in the oogonia and early oocytes in females, demonstrating that Eapiwi could be used as an early germ cell marker in E. ancora. Subsequent immunohistochemical analyses regarding the spatial and temporal distribution patterns of early germ cells in mesentery tissues revealed that early germ cells were present throughout the year in the mesentery tissue we examined, regardless of the sexual reproductive cycle. In particular, small numbers of early germ cells were observed in specific sites of mesentery tissues with fully matured gonads in both sexes. These early germ cells were not released together with mature gametes during the spawning period and remained in the mesentery tissues. These results suggested that these early germ cells most likely serve as a reservoir of germline cells and that some of these cells would produce differentiated germ cells for the upcoming sexual reproduction period; hence, these cells would function as GSCs. Our data provide new information for understanding continuous gamete production in corals.

  5. Spontaneous and UV-induced variations in the activity of biomass synthesis in Candida utilis haploid and diploid strains

    International Nuclear Information System (INIS)

    Kondrat'eva, T.F.; Lin'kova, M.A.; Lobacheva, N.A.

    1988-01-01

    Candida utilis diploid strains have greater variations induced by UV irradiation in the activity of biomass synthesis as compared with the parent haploid culture. Clones with an activity of the synthesis greater that the mean population one appear more frequently in the diploid strains. Mathematical analysis has confirmed the significance of the results and the hypothesis according to which the frequency of variants more active in biomass synthesis rises after the action of UV

  6. Mutation induction in haploid yeast after split-dose radiation-exposure. I. Fractionated UV-irradiation.

    Science.gov (United States)

    Schenk, K; Zölzer, F; Kiefer, J

    1989-01-01

    Mutation induction was investigated in wild-type haploid yeast Saccharomyces cerevisiae after split-dose UV-irradiation. Cells were exposed to fractionated 254 nm-UV-doses separated by intervals from 0 to 6 h with incubation either on non-nutrient or nutrient agar between. The test parameter was resistance to canavanine. If modifications of sensitivity due to incubation are appropriately taken into account there is no change of mutation frequency.

  7. Systems Toxicology of Male Reproductive Development: Profiling 774 Chemicals for Molecular Targets and Adverse Outcomes

    Data.gov (United States)

    U.S. Environmental Protection Agency — Background: Trends in male reproductive health have been reported for increased rates of testicular germ cell tumors, low semen quality, cryptorchidism, and...

  8. Transformation of haploid, microspore-derived cell suspension protoplasts of rice (Oryza sativa L.).

    Science.gov (United States)

    Chaïr, H; Legavre, T; Guiderdoni, E

    1996-06-01

    We compared the transient activity of three cereal gene-derived promoter-gus fusions and the efficiency of selection mediated by three different selectable genes in a polyethylene glycol transformation system with haploid cell suspension protoplasts of rice. The maize ubiquitin promoter was found to be the most active in transformed protoplasts, and selection on ammonium glufosinate mediated by the bar gene was the most efficient for producing resistant calluses. Cotransformation of protoplasts with two separate plasmids carrying the gus and the bar genes, at either a 2∶1 or 1∶1 ratio, led to 0.8 × 10(-5) and 1.6 × 10(-5) resistant callus recovery frequencies and 59.7 and 37.9 cotransformation efficiencies respectively. No escapes were detected in dot blot analyses of 100 resistant calluses with a probe consisting of the bar coding region. Cotransformation efficiency, based on resistance to basta and β-glucuronidase staining of the leaf tissue of 115 regenerated plants, was 47%. Resistance tests and Southern analysis of seed progenies of three diploid transgenic plants demonstrated homozygous integration of multiple copies of the transgene at one locus at least in the first plant, heterozygous integration at one locus in the second plant and heterozygous integration at two loci in the third plant.

  9. Mapping of Novel QTL Regulating Grain Shattering Using Doubled Haploid Population in Rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Gyu-Ho Lee

    2016-01-01

    Full Text Available The critical evolutionary step during domestication of major cereals was elimination of seed shattering because the easy-to-shatter trait in wild relatives results in a severe reduction in yield. In this study, we analyzed the QTLs associated with shattering employing a high-density genetic map in doubled haploid (DH population of rice (Oryza sativa L.. A genetic linkage map was generated with 217 microsatellite markers spanning 2082.4 cM and covering 12 rice chromosomes with an average interval of 9.6 cM between markers based on 120 DHLs derived from a cross between Cheongcheong indica type cultivar and Nagdong japonica type cultivar. In the QTL analysis, five QTLs pertaining to the breaking tensile strength (BTS were detected in 2013 and 2015. Two regions of the QTLs related to BTS on chromosome 1 and chromosome 6 were detected. Several important genes are distributed in 1 Mbp region of the QTL on chromosome 6 and they are related to the formation of abscission layer. We decide to name this QTL qSh6 and the candidate genes in the qSh6 region can be employed usefully in further research for cloning.

  10. Haploid deletion strains of Saccharomyces cerevisiae that determine survival during space flight

    Science.gov (United States)

    Johanson, Kelly; Allen, Patricia L.; Gonzalez-Villalobos, Romer A.; Nesbit, Jacqueline; Nickerson, Cheryl A.; Höner zu Bentrup, Kerstin; Wilson, James W.; Ramamurthy, Rajee; D'Elia, Riccardo; Muse, Kenneth E.; Hammond, Jeffrey; Freeman, Jake; Stodieck, Louis S.; Hammond, Timothy G.

    2007-02-01

    This study identifies genes that determine survival during a space flight, using the model eukaryotic organism, Saccharomyces cerevisiae. Select strains of a haploid yeast deletion series grew during storage in distilled water in space, but not in ground based static or clinorotation controls. The survival advantages in space in distilled water include a 133-fold advantage for the deletion of PEX19, a chaperone and import receptor for newly- synthesized class I peroxisomal membrane proteins, to 77-40 fold for deletion strains lacking elements of aerobic respiration, isocitrate metabolism, and mitochondrial electron transport. Following automated addition of rich growth media, the space flight was associated with a marked survival advantage of strains with deletions in catalytically active genes including hydrolases, oxidoreductases and transferases. When compared to static controls, space flight was associated with a marked survival disadvantage of deletion strains lacking transporter, antioxidant and catalytic activity. This study identifies yeast deletion strains with a survival advantage during storage in distilled water and space flight, and amplifies our understanding of the genes critical for survival in space.

  11. Exact Markov chain and approximate diffusion solution for haploid genetic drift with one-way mutation.

    Science.gov (United States)

    Hössjer, Ola; Tyvand, Peder A; Miloh, Touvia

    2016-02-01

    The classical Kimura solution of the diffusion equation is investigated for a haploid random mating (Wright-Fisher) model, with one-way mutations and initial-value specified by the founder population. The validity of the transient diffusion solution is checked by exact Markov chain computations, using a Jordan decomposition of the transition matrix. The conclusion is that the one-way diffusion model mostly works well, although the rate of convergence depends on the initial allele frequency and the mutation rate. The diffusion approximation is poor for mutation rates so low that the non-fixation boundary is regular. When this happens we perturb the diffusion solution around the non-fixation boundary and obtain a more accurate approximation that takes quasi-fixation of the mutant allele into account. The main application is to quantify how fast a specific genetic variant of the infinite alleles model is lost. We also discuss extensions of the quasi-fixation approach to other models with small mutation rates. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Production of haploid plant of 'Banpeiyu' pummelo [Citrus maxima (Burm.) Merr.] by pollination with soft X-ray-irradiated pollen

    International Nuclear Information System (INIS)

    Yahata, Masaki; Yasuda, Kiichi; Kunitake, Hisato; Nagasawa, Kohji; Harusaki, Seiichi; Komatsu, Haruki

    2010-01-01

    To induce haploid plants in Citrus maxima (Burm.) Merr. 'Banpeiyu', we evaluated the effect of pollination with soft X-ray-irradiated pollen on fruit set and seed development, and carried out ovule culture. When 'Banpeiyu' pummelo pistils were pollinated with X-ray-irradiated pollen of 'Fukuhara' sweet orange [C. sinensis (L.) Osbeck], the exposure doses affected the fruit set. The number of seeds per fruit was also affected by the exposure dose, and tended to decrease as the dose increased; however, all developed seeds obtained from these crosses were diploid. In the ovule culture of 'Banpeiyu' pummelo, six embryoids shown haploidy were obtained in all treatments. One haploid plantlet with 9 chromosomes was regenerated from an embryoid in a culture of ovules established 40 days after pollination with 400 Gray (Gy)-irradiated pollen of 'Tosa-buntan' pummelo (C. maxima). This haploid was suggested to be derived from 'Banpeiyu' pummelo by random amplified polymorphic DNA (RAPD) and cleaved amplified polymorphic sequence (CAPS) analysis. (author)

  13. Breeding of a xylose-fermenting hybrid strain by mating genetically engineered haploid strains derived from industrial Saccharomyces cerevisiae.

    Science.gov (United States)

    Inoue, Hiroyuki; Hashimoto, Seitaro; Matsushika, Akinori; Watanabe, Seiya; Sawayama, Shigeki

    2014-12-01

    The industrial Saccharomyces cerevisiae IR-2 is a promising host strain to genetically engineer xylose-utilizing yeasts for ethanol fermentation from lignocellulosic hydrolysates. Two IR-2-based haploid strains were selected based upon the rate of xylulose fermentation, and hybrids were obtained by mating recombinant haploid strains harboring heterogeneous xylose dehydrogenase (XDH) (wild-type NAD(+)-dependent XDH or engineered NADP(+)-dependent XDH, ARSdR), xylose reductase (XR) and xylulose kinase (XK) genes. ARSdR in the hybrids selected for growth rates on yeast extract-peptone-dextrose (YPD) agar and YP-xylose agar plates typically had a higher activity than NAD(+)-dependent XDH. Furthermore, the xylose-fermenting performance of the hybrid strain SE12 with the same level of heterogeneous XDH activity was similar to that of a recombinant strain of IR-2 harboring a single set of genes, XR/ARSdR/XK. These results suggest not only that the recombinant haploid strains retain the appropriate genetic background of IR-2 for ethanol production from xylose but also that ARSdR is preferable for xylose fermentation.

  14. Management of primary malignant germ cell tumor of the mediastinum

    International Nuclear Information System (INIS)

    Sakurai, Hiroyuki; Asamura, Hisao; Suzuki, Kenji; Watanabe, Shun-ichi; Tsuchiya, Ryosuke

    2004-01-01

    Primary mediastinal malignant germ cell tumors (GCTs) are rare and have a worse prognosis than their gonadal counterparts. Although multimodality treatment is a standard therapeutic strategy in mediastinal GCTs, the clinical implications of surgical intervention remain unclear. Forty-eight patients with primary mediastinal malignant GCT who were treated at the National Cancer Center Hospital, Tokyo, from 1962 to 2002 were studied retrospectively with regard to their histology and clinical profile. Mediastinal GCT occurred predominantly in young males, with a mean age of 28.8 years at the time of diagnosis. There were 46 males (96%) and two females (4%). Histologically, seven patients (15%) were diagnosed as having pure seminoma and 41 (85%) had nonseminomatous GCT. Treatment consisted of surgery alone in nine patients, surgery followed by chemotherapy in two, and chemotherapy followed by surgery in 20. The other 17 patients received chemotherapy and/or radiotherapy without surgery. Of these latter 17 patients, 14 developed progressive disease and three were followed up with a sustained partial response. Among the 31 patients who underwent surgery, complete resection was performed in 27 (87%) and incomplete resection was performed in four (13%). Twelve (41%) patients had elevated serum tumor marker levels preoperatively. Among the 20 patients who received preoperative chemotherapy, viable cells were found in the resected specimen in six (30%). With regard to tumor recurrence in patients with surgical intervention, the preoperative serum tumor marker levels and the presence of viable cells in the resected specimen were significantly associated with recurrence. There was no significant association between surgical curability and recurrence. The 5-year overall survival rate in all 48 patients was 45.5%. Surgical intervention for mediastinal GCT may be needed to remove a chemotherapy-refractory tumor or to assess the pathological response to chemotherapy to determine

  15. Parental Occupational Exposure to Organic Solvents and Testicular Germ Cell Tumors in their Offspring

    DEFF Research Database (Denmark)

    Le Cornet, Charlotte; Fervers, Béatrice; Pukkala, Eero

    2017-01-01

    BACKGROUND: Testicular germ cell tumors (TGCT) were suggested to have a prenatal environmentally related origin. The potential endocrine disrupting properties of certain solvents may interfere with the male genital development in utero. OBJECTIVES: We aimed to assess the association between......-Nordic Occupational Cancer Study Job-Exposure Matrix. Conditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Overall, no association was found between prenatal maternal exposure to solvents and TGCT risk. In subset analyses using only mothers for whom...

  16. Fully-Automated High-Throughput NMR System for Screening of Haploid Kernels of Maize (Corn by Measurement of Oil Content.

    Directory of Open Access Journals (Sweden)

    Hongzhi Wang

    Full Text Available One of the modern crop breeding techniques uses doubled haploid plants that contain an identical pair of chromosomes in order to accelerate the breeding process. Rapid haploid identification method is critical for large-scale selections of double haploids. The conventional methods based on the color of the endosperm and embryo seeds are slow, manual and prone to error. On the other hand, there exists a significant difference between diploid and haploid seeds generated by high oil inducer, which makes it possible to use oil content to identify the haploid. This paper describes a fully-automated high-throughput NMR screening system for maize haploid kernel identification. The system is comprised of a sampler unit to select a single kernel to feed for measurement of NMR and weight, and a kernel sorter to distribute the kernel according to the measurement result. Tests of the system show a consistent accuracy of 94% with an average screening time of 4 seconds per kernel. Field test result is described and the directions for future improvement are discussed.

  17. Fully-Automated High-Throughput NMR System for Screening of Haploid Kernels of Maize (Corn) by Measurement of Oil Content

    Science.gov (United States)

    Xu, Xiaoping; Huang, Qingming; Chen, Shanshan; Yang, Peiqiang; Chen, Shaojiang; Song, Yiqiao

    2016-01-01

    One of the modern crop breeding techniques uses doubled haploid plants that contain an identical pair of chromosomes in order to accelerate the breeding process. Rapid haploid identification method is critical for large-scale selections of double haploids. The conventional methods based on the color of the endosperm and embryo seeds are slow, manual and prone to error. On the other hand, there exists a significant difference between diploid and haploid seeds generated by high oil inducer, which makes it possible to use oil content to identify the haploid. This paper describes a fully-automated high-throughput NMR screening system for maize haploid kernel identification. The system is comprised of a sampler unit to select a single kernel to feed for measurement of NMR and weight, and a kernel sorter to distribute the kernel according to the measurement result. Tests of the system show a consistent accuracy of 94% with an average screening time of 4 seconds per kernel. Field test result is described and the directions for future improvement are discussed. PMID:27454427

  18. Transplantation of germ cells from glial cell line-derived neurotrophic factor-overexpressing mice to host testes depleted of endogenous spermatogenesis by fractionated irradiation

    NARCIS (Netherlands)

    Creemers, L. B.; Meng, X.; den Ouden, K.; van Pelt, A. M. M.; Izadyar, F.; Santoro, M.; Sariola, H.; de rooij, D. G.

    2002-01-01

    With a novel method of eliminating spermatogenesis in host animals, male germ cells isolated from mice with targeted overexpression of glial cell line-derived neurotrophic factor (GDNF) were transplanted to evaluate their ability to reproduce the phenotype previously found in the transgenic animals.

  19. Lipid phosphate phosphatase activity regulates dispersal and bilateral sorting of embryonic germ cells in Drosophila

    Science.gov (United States)

    Renault, Andrew D.; Kunwar, Prabhat S.; Lehmann, Ruth

    2010-01-01

    In Drosophila, germ cell survival and directionality of migration are controlled by two lipid phosphate phosphatases (LPP), wunen (wun) and wunen-2 (wun2). wun wun2 double mutant analysis reveals that the two genes, hereafter collectively called wunens, act redundantly in primordial germ cells. We find that wunens mediate germ cell-germ cell repulsion and that this repulsion is necessary for germ cell dispersal and proper transepithelial migration at the onset of migration and for the equal sorting of the germ cells between the two embryonic gonads during their migration. We propose that this dispersal function optimizes adult fecundity by assuring maximal germ cell occupancy of both gonads. Furthermore, we find that the requirement for wunens in germ cell survival can be eliminated by blocking germ cell migration. We suggest that this essential function of Wunen is needed to maintain cell integrity in actively migrating germ cells. PMID:20431117

  20. Treatment Options By Stage (Ovarian Germ Cell Tumors)

    Science.gov (United States)

    ... Germ Cell Tumors Treatment (PDQ®)–Patient Version Treatment Option Overview Go to Health Professional Version Key Points ... and restore) the body’s blood cells. New treatment options Combination chemotherapy (the use of more than one ...

  1. Germ Cells are Made Semiotically Competent During Evolution

    DEFF Research Database (Denmark)

    Giorgi, Franco; Bruni, Luis Emilio

    2016-01-01

    Germ cells are cross-roads of development and evolution. They define the origin of every new generation and, at the same time, represent the biological end-product of any mature organism. Germ cells are endowed with the following capacities: (1) to store a self-descriptive program, (2......) to accumulate a protein-synthesizing machinery (ribosomes), and (3) to incorporate enough nourishment to sustain embryonic development (yolk). To accomplish this goal, germ cells do not simply unfold a pre-determined program or realize a sole instructive role. On the contrary, due to the complexity...... milieu and experience the compatibility of selected developmental sequences. The question of which signaling pathways are activated at each developmental stage does not result from a strictly predetermined program instructing germ cell stemness. Rather, each developmental sequence is an open...

  2. Critical mutation rate has an exponential dependence on population size in haploid and diploid populations.

    Directory of Open Access Journals (Sweden)

    Elizabeth Aston

    Full Text Available Understanding the effect of population size on the key parameters of evolution is particularly important for populations nearing extinction. There are evolutionary pressures to evolve sequences that are both fit and robust. At high mutation rates, individuals with greater mutational robustness can outcompete those with higher fitness. This is survival-of-the-flattest, and has been observed in digital organisms, theoretically, in simulated RNA evolution, and in RNA viruses. We introduce an algorithmic method capable of determining the relationship between population size, the critical mutation rate at which individuals with greater robustness to mutation are favoured over individuals with greater fitness, and the error threshold. Verification for this method is provided against analytical models for the error threshold. We show that the critical mutation rate for increasing haploid population sizes can be approximated by an exponential function, with much lower mutation rates tolerated by small populations. This is in contrast to previous studies which identified that critical mutation rate was independent of population size. The algorithm is extended to diploid populations in a system modelled on the biological process of meiosis. The results confirm that the relationship remains exponential, but show that both the critical mutation rate and error threshold are lower for diploids, rather than higher as might have been expected. Analyzing the transition from critical mutation rate to error threshold provides an improved definition of critical mutation rate. Natural populations with their numbers in decline can be expected to lose genetic material in line with the exponential model, accelerating and potentially irreversibly advancing their decline, and this could potentially affect extinction, recovery and population management strategy. The effect of population size is particularly strong in small populations with 100 individuals or less; the

  3. Quantifying rooting at depth in a wheat doubled haploid population with introgression from wild emmer.

    Science.gov (United States)

    Clarke, Christina K; Gregory, Peter J; Lukac, Martin; Burridge, Amanda J; Allen, Alexandra M; Edwards, Keith J; Gooding, Mike J

    2017-09-01

    The genetic basis of increased rooting below the plough layer, post-anthesis in the field, of an elite wheat line (Triticum aestivum 'Shamrock') with recent introgression from wild emmer (T. dicoccoides), is investigated. Shamrock has a non-glaucous canopy phenotype mapped to the short arm of chromosome 2B (2BS), derived from the wild emmer. A secondary aim was to determine whether genetic effects found in the field could have been predicted by other assessment methods. Roots of doubled haploid (DH) lines from a winter wheat ('Shamrock' × 'Shango') population were assessed using a seedling screen in moist paper rolls, in rhizotrons to the end of tillering, and in the field post-anthesis. A linkage map was produced using single nucleotide polymorphism markers to identify quantitative trait loci (QTLs) for rooting traits. Shamrock had greater root length density (RLD) at depth than Shango, in the field and within the rhizotrons. The DH population exhibited diversity for rooting traits within the three environments studied. QTLs were identified on chromosomes 5D, 6B and 7B, explaining variation in RLD post-anthesis in the field. Effects associated with the non-glaucous trait on RLD interacted significantly with depth in the field, and some of this interaction mapped to 2BS. The effect of genotype was strongly influenced by the method of root assessment, e.g. glaucousness expressed in the field was negatively associated with root length in the rhizotrons, but positively associated with length in the seedling screen. To our knowledge, this is the first study to identify QTLs for rooting at depth in field-grown wheat at mature growth stages. Within the population studied here, our results are consistent with the hypothesis that some of the variation in rooting is associated with recent introgression from wild emmer. The expression of genetic effects differed between the methods of root assessment. © The Author 2017. Published by Oxford University Press on behalf of the

  4. Comparative radiation genetics. What we learnt from our studies on Medaka germ cell mutagenesis

    International Nuclear Information System (INIS)

    Shima, Akihiro

    2004-01-01

    Having been interested in studying germ cell mutagenesis from the biodiversity viewpoint, in 1985 we started developing a nonmammalian specific-locus test (SLT) system using the Medaka, Oryzias latipes. The tester strain with five marker loci, which is a prerequisite for SLT, was established by consecutive crossings of five spontaneous single mutants followed by selection based on the phenotype of each mutant. The genetic endpoints available were dominant lethal mutations (DLM), total specific-locus mutations (TSLM) and viable specific-locus mutations. Using γ-rays, ethylnitrosourea and Fe-ion beam as mutagens to which wild type males or females were exposed, we screened approx. 1.6 million F1 embryos that correspond to approx. 4.7 million loci. In an attempt to best express the comparative sensitivity of Medaka germ cells to the genetic effects of γ-rays, the gametic doubling doses for acute and high-dose γ-rays were estimated. Extensive sex differences within the wild type (HNI) strain as well as strain differences in male germ cells between the two wild type strains (HNI and Sakura) were notably found in doubling doses for DLM and TSLM. Interestingly, among these values, the doubling dose for TSLM in spermatogonia of the HNI strain (0.33 Gy) nearly coincided with that estimated from the Russell 7-locus system of mice (0.44 Gy). Our data also suggested that the initial genomic changes induced in male germ cells would not straightforwardly manifest themselves as phenotypic effects in F1 progeny, but that twofold checks, one a prefertilization check in the gonads against genomic alterations using DNA repair machinery as well as apoptotic response, and the other postfertilization check in developing embryos through dominant lethal effects. should operate to restore or ameliorate those genomic changes. More mechanistically, AP/PCR-RAPD DNA fingerprinting was employed in order to scan as wider regions of the zygotic genome as possible. These anonymous DNA markers

  5. Surrogate production of eggs and sperm by intrapapillary transplantation of germ cells in cytoablated adult fish.

    Directory of Open Access Journals (Sweden)

    Sullip Kumar Majhi

    Full Text Available Germ cell transplantation (GCT is a promising assisted reproductive technology for the conservation and propagation of endangered and valuable genetic resources. In teleost fish, GCT in adult gonads has been achieved only in male recipients, limiting greatly the usefulness of this technique in situations where both sexes need equal and timely attention for conservation and/or propagation. Here we describe a simplified GCT approach that ultimately leads to production of donor-derived eggs and sperm in considerably short time. Donor germ cells isolated from young pejerrey Odontesthes bonariensis (Atherinopsidae were transplanted non-surgically through the genital papilla into the sexually mature gonads of Patagonian pejerrey O. hatcheri recipients whose gonads have been depleted of endogenous GCs by heat (26°C and chemical treatment (four doses of Busulfan at 30 mg/kg and 40 mg/kg for females and males, respectively. Transplanted spermatogonial and oogonial cells were able to recolonize the recipients' gonads and produce functional donor origin eggs and sperm within 7 months from the GCT. We confirmed the presence of donor-derived gametes by PCR in 17% and 5% of the surrogate O. hatcheri fathers and mothers, respectively. The crosses between surrogate fathers and O. bonariensis mothers yielded 12.6-39.7% pure O. bonariensis and that between a surrogate mother and an O. bonariensis father yielded 52.2% pure O. bonariensis offspring. Our findings confirm that transplantation of germ cells into sexually competent adult fish by non-surgical methods allows the production of functional donor-derived eggs and sperm in a considerably short time. The methods described here could play a vital role in conservation and rapid propagation of endangered fish genetic resources.

  6. Surrogate production of eggs and sperm by intrapapillary transplantation of germ cells in cytoablated adult fish.

    Science.gov (United States)

    Majhi, Sullip Kumar; Hattori, Ricardo Shohei; Rahman, Sheikh Mustafizur; Strüssmann, Carlos Augusto

    2014-01-01

    Germ cell transplantation (GCT) is a promising assisted reproductive technology for the conservation and propagation of endangered and valuable genetic resources. In teleost fish, GCT in adult gonads has been achieved only in male recipients, limiting greatly the usefulness of this technique in situations where both sexes need equal and timely attention for conservation and/or propagation. Here we describe a simplified GCT approach that ultimately leads to production of donor-derived eggs and sperm in considerably short time. Donor germ cells isolated from young pejerrey Odontesthes bonariensis (Atherinopsidae) were transplanted non-surgically through the genital papilla into the sexually mature gonads of Patagonian pejerrey O. hatcheri recipients whose gonads have been depleted of endogenous GCs by heat (26°C) and chemical treatment (four doses of Busulfan at 30 mg/kg and 40 mg/kg for females and males, respectively). Transplanted spermatogonial and oogonial cells were able to recolonize the recipients' gonads and produce functional donor origin eggs and sperm within 7 months from the GCT. We confirmed the presence of donor-derived gametes by PCR in 17% and 5% of the surrogate O. hatcheri fathers and mothers, respectively. The crosses between surrogate fathers and O. bonariensis mothers yielded 12.6-39.7% pure O. bonariensis and that between a surrogate mother and an O. bonariensis father yielded 52.2% pure O. bonariensis offspring. Our findings confirm that transplantation of germ cells into sexually competent adult fish by non-surgical methods allows the production of functional donor-derived eggs and sperm in a considerably short time. The methods described here could play a vital role in conservation and rapid propagation of endangered fish genetic resources.

  7. Perchlorate Exposure Reduces Primordial Germ Cell Number in Female Threespine Stickleback.

    Directory of Open Access Journals (Sweden)

    Ann M Petersen

    Full Text Available Perchlorate is a common aquatic contaminant that has long been known to affect thyroid function in vertebrates, including humans. More recently perchlorate has been shown to affect primordial sexual differentiation in the aquatic model fishes zebrafish and threespine stickleback, but the mechanism has been unclear. Stickleback exposed to perchlorate from fertilization have increased androgen levels in the embryo and disrupted reproductive morphologies as adults, suggesting that perchlorate could disrupt the earliest stages of primordial sexual differentiation when primordial germ cells (PGCs begin to form the gonad. Female stickleback have three to four times the number of PGCs as males during the first weeks of development. We hypothesized that perchlorate exposure affects primordial sexual differentiation by reducing the number of germ cells in the gonad during an important window of stickleback sex determination at 14-18 days post fertilization (dpf. We tested this hypothesis by quantifying the number of PGCs at 16 dpf in control and 100 mg/L perchlorate-treated male and female stickleback. Perchlorate exposure from the time of fertilization resulted in significantly reduced PGC number only in genotypic females, suggesting that the masculinizing effects of perchlorate observed in adult stickleback may result from early changes to the number of PGCs at a time critical for sex determination. To our knowledge, this is the first evidence of a connection between an endocrine disruptor and reduction in PGC number prior to the first meiosis during sex determination. These findings suggest that a mode of action of perchlorate on adult reproductive phenotypes in vertebrates, including humans, such as altered fecundity and sex reversal or intersex gonads, may stem from early changes to germ cell development.

  8. Preconception exposures to potential germ-cell mutagens

    International Nuclear Information System (INIS)

    Draper, G.

    2008-01-01

    Radiation and other agents can cause germ-cell mutations in animal systems. No human germ-cell mutagen has been identified, but this does not mean that human germ-cells are not vulnerable to mutagenesis. There has been particular concern about the possible health effects on offspring following parental preconception exposure to ionizing radiation - both occupational and therapeutic. A strong association with preconception radiation exposure in the fathers of the cases was found in a case-control study of young people with leukaemia living near the Sellafield nuclear plant in the UK. Subsequent studies of workers occupationally exposed to ionizing radiation have failed to confirm these findings. No statistically significant effects have been reported from studies of possible indicators of germ-cell mutagenesis in the A-bomb survivors. Studies of offspring of cancer survivors who receive radiotherapy and mutagenic chemotherapy have found no evidence of germ-cell mutagenesis. Failure to detect human germ-cell mutagenic agents may be a consequence of inadequate study sizes or insufficiently sensitive laboratory techniques. (authors)

  9. MRI of intracranial germ-cell tumours

    International Nuclear Information System (INIS)

    Liang, L.; Korogi, Y.; Sugahara, T.; Ikushima, I.; Shigematsu, Y.; Okuda, T.; Takahashi, M.; Kochi, M.; Ushio, Y.

    2002-01-01

    Abstract. Our aim was to review the MRI appearances of primary intracranial germ-cell tumours (GCT). We reviewed the MRI studies of 32 patients: 19 with germinomas, five with teratomas, one with an embryonal carcinoma, five with mixed and two with malignant nongerminomatous GCT. Eleven were in the pineal region, 12 suprasellar, five in the both sites, two in the basal ganglia and two in the corpus callosum. Contrast-enhanced images were available for 27 patients. The solid parts of GCT were nearly isointense with grey matter on both T1- and T2-weighted images. In seven patients with nongerminomatous GCT high-signal components were found on T1-weighted images, representing haemorrhage, high-protein fluid or fat. Cystic components were detected in 17 of 27 patients; eight germinomas and all nine nongerminomatous GCT had cysts. The solid components of germinomas enhanced homogeneously in eight cases and heterogeneously in 10, while all nongerminomatous GCT showed heterogeneous enhancement. MRI features tumours can facilitate correct diagnosis of GCT, including histological subtypes. (orig.)

  10. Critical role of CCDC6 in the neoplastic growth of testicular germ cell tumors

    International Nuclear Information System (INIS)

    Staibano, Stefania; Fusco, Alfredo; Chieffi, Paolo; Celetti, Angela; Ilardi, Gennaro; Leone, Vincenza; Luise, Chiara; Merolla, Francesco; Esposito, Francesco; Morra, Francesco; Siano, Maria; Franco, Renato

    2013-01-01

    DNA damage response has been clearly described as an anti-cancer barrier in early human tumorigenesis. Moreover, interestingly, testicular germ cell tumors (TGCTs) have been reported to lack the DNA Damage Response (DDR) pathway activation. CCDC6 is a pro-apoptotic phosphoprotein substrate of the kinase ataxia telangectasia mutated (ATM) able to sustain DNA damage checkpoint in response to genotoxic stress and is commonly rearranged in malignancies upon fusion with different partners. In our study we sought to determine whether CCDC6 could have a role in the patho-genesis of testicular germ cell tumors. To achieve this aim, analysis for CCDC6 expression has been evaluated on serial sections of the mouse testis by immunohistochemistry and on separate populations of murine testicular cells by western blot. Next, the resistance to DNA damage-induced apoptosis and the production of reactive oxygen species has been investigated in GC1 cells, derived from immortalized type B murine germ cells, following CCDC6 silencing. Finally, the CCDC6 expression in normal human testicular cells, in Intratubular Germ Cell Neoplasia Unclassified (IGCNU), in a large series of male germ cell tumours and in the unique human seminoma TCam2 cell line has been evaluated by immunohistochemistry and by Western Blot analyses. The analysis of the CCDC6 expression revealed its presence in Sertoli cells and in spermatogonial cells. CCDC6 loss was the most consistent feature among the primary tumours and TCam2 cells. Interestingly, following treatment with low doses of H 2 O 2 , the silencing of CCDC6 in GC1 cells caused a decrease in the oxidized form of cytochrome c and low detection of Bad, PARP-1 and Caspase 3 proteins. Moreover, in the silenced cells, upon oxidative damage, the cell viability was protected, the γH2AX activation was impaired and the Reactive Oxygen Species (ROS) release was decreased. Therefore, our results suggest that the loss of CCDC6 could aid the spermatogonial cells to

  11. Novel somatic and germline mutations in intracranial germ cell tumours.

    Science.gov (United States)

    Wang, Linghua; Yamaguchi, Shigeru; Burstein, Matthew D; Terashima, Keita; Chang, Kyle; Ng, Ho-Keung; Nakamura, Hideo; He, Zongxiao; Doddapaneni, Harshavardhan; Lewis, Lora; Wang, Mark; Suzuki, Tomonari; Nishikawa, Ryo; Natsume, Atsushi; Terasaka, Shunsuke; Dauser, Robert; Whitehead, William; Adekunle, Adesina; Sun, Jiayi; Qiao, Yi; Marth, Gábor; Muzny, Donna M; Gibbs, Richard A; Leal, Suzanne M; Wheeler, David A; Lau, Ching C

    2014-07-10

    Intracranial germ cell tumours (IGCTs) are a group of rare heterogeneous brain tumours that are clinically and histologically similar to the more common gonadal GCTs. IGCTs show great variation in their geographical and gender distribution, histological composition and treatment outcomes. The incidence of IGCTs is historically five- to eightfold greater in Japan and other East Asian countries than in Western countries, with peak incidence near the time of puberty. About half of the tumours are located in the pineal region. The male-to-female incidence ratio is approximately 3-4:1 overall, but is even higher for tumours located in the pineal region. Owing to the scarcity of tumour specimens available for research, little is currently known about this rare disease. Here we report the analysis of 62 cases by next-generation sequencing, single nucleotide polymorphism array and expression array. We find the KIT/RAS signalling pathway frequently mutated in more than 50% of IGCTs, including novel recurrent somatic mutations in KIT, its downstream mediators KRAS and NRAS, and its negative regulator CBL. Novel somatic alterations in the AKT/mTOR pathway included copy number gains of the AKT1 locus at 14q32.33 in 19% of patients, with corresponding upregulation of AKT1 expression. We identified loss-of-function mutations in BCORL1, a transcriptional co-repressor and tumour suppressor. We report significant enrichment of novel and rare germline variants in JMJD1C, which codes for a histone demethylase and is a coactivator of the androgen receptor, among Japanese IGCT patients. This study establishes a molecular foundation for understanding the biology of IGCTs and suggests potentially promising therapeutic strategies focusing on the inhibition of KIT/RAS activation and the AKT1/mTOR pathway.

  12. Novel somatic and germline mutations in intracranial germ cell tumors

    Science.gov (United States)

    Wang, Linghua; Yamaguchi, Shigeru; Burstein, Matthew D.; Terashima, Keita; Chang, Kyle; Ng, Ho-Keung; Nakamura, Hideo; He, Zongxiao; Doddapaneni, Harshavardhan; Lewis, Lora; Wang, Mark; Suzuki, Tomonari; Nishikawa, Ryo; Natsume, Atsushi; Terasaka, Shunsuke; Dauser, Robert; Whitehead, William; Adekunle, Adesina; Sun, Jiayi; Qiao, Yi; Marth, Gábor; Muzny, Donna M.; Gibbs, Richard A.; Leal, Suzanne M.; Wheeler, David A.; Lau, Ching C.

    2015-01-01

    Intracranial germ cell tumors (IGCTs) are a group of rare heterogeneous brain tumors which are clinically and histologically similar to the more common gonadal GCTs. IGCTs show great variation in their geographic and gender distribution, histological composition and treatment outcomes. The incidence of IGCTs is historically 5–8 fold greater in Japan and other East Asian countries than in Western countries1 with peak incidence near the time of puberty2. About half of the tumors are located in the pineal region. The male-to-female incidence ratio is approximately 3–4:1 overall but even higher for tumors located in the pineal region3. Due to the scarcity of tumor specimens available for research, little is currently known about this rare disease. Here we report the analysis of 62 cases by next generation sequencing, SNP array and expression array. We find the KIT/RAS signaling pathway frequently mutated in over 50% of IGCTs including novel recurrent somatic mutations in KIT, its downstream mediators KRAS and NRAS, and its negative regulator CBL. Novel somatic alterations in the AKT/mTOR pathway included copy number gain of the AKT1 locus at 14q32.33 in 19% of patients, with corresponding upregulation of AKT1 expression. We identified loss-of-function mutations in BCORL1, a transcriptional corepressor and tumor suppressor. We report significant enrichment of novel and rare germline variants in JMJD1C, a histone demethylase and coactivator of the androgen receptor, among Japanese IGCT patients. This study establishes a molecular foundation for understanding the biology of IGCTs and suggests potentially promising therapeutic strategies focusing on the inhibition of KIT/RAS activation and the AKT1/mTOR pathway. PMID:24896186

  13. The role of epistatic interactions underpinning resistance to parasitic Varroa mites in haploid honey bee (Apis mellifera) drones.

    Science.gov (United States)

    Conlon, Benjamin H; Frey, Eva; Rosenkranz, Peter; Locke, Barbara; Moritz, Robin F A; Routtu, Jarkko

    2018-06-01

    The Red Queen hypothesis predicts that host-parasite coevolutionary dynamics can select for host resistance through increased genetic diversity, recombination and evolutionary rates. However, in haplodiploid organisms such as the honeybee (Apis mellifera), models suggest the selective pressure is weaker than in diploids. Haplodiploid sex determination, found in A. mellifera, can allow deleterious recessive alleles to persist in the population through the diploid sex with negative effects predominantly expressed in the haploid sex. To overcome these negative effects in haploid genomes, epistatic interactions have been hypothesized to play an important role. Here, we use the interaction between A. mellifera and the parasitic mite Varroa destructor to test epistasis in the expression of resistance, through the inhibition of parasite reproduction, in haploid drones. We find novel loci on three chromosomes which explain over 45% of the resistance phenotype. Two of these loci interact only additively, suggesting their expression is independent of each other, but both loci interact epistatically with the third locus. With drone offspring inheriting only one copy of the queen's chromosomes, the drones will only possess one of two queen alleles throughout the years-long lifetime of the honeybee colony. Varroa, in comparison, completes its highly inbred reproductive cycle in a matter of weeks, allowing it to rapidly evolve resistance. Faced with the rapidly evolving Varroa, a diversity of pathways and epistatic interactions for the inhibition of Varroa reproduction could therefore provide a selective advantage to the high levels of recombination seen in A. mellifera. This allows for the remixing of phenotypes despite a fixed queen genotype. © 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2018 European Society For Evolutionary Biology.

  14. Maternal smoking and testicular germ cell tumors.

    Science.gov (United States)

    McGlynn, Katherine A; Zhang, Yawei; Sakoda, Lori C; Rubertone, Mark V; Erickson, Ralph L; Graubard, Barry I

    2006-10-01

    Testicular germ cell tumors (TGCT) are the most common cancer among men ages 15 to 35 years in the United States. The well-established TGCT risk factors cryptorchism, prior diagnosis of TGCT, and family history of testicular cancer indicate that exposures in early life and/or in the familial setting may be critical to determining risk. Previous reports of familial clustering of lung cancer in mothers and testicular cancers in sons suggest that passive smoking in childhood may be such an exposure. To clarify the relationship of passive smoking exposure to TGCT risk, data from 754 cases and 928 controls enrolled in the Servicemen's Testicular Tumor Environmental and Endocrine Determinants study were analyzed. Data from 1,086 mothers of the cases and controls were also examined. Overall, there was no relationship between maternal [odds ratio (OR), 1.1; 95% confidence interval (95% CI), 0.9-1.3] or paternal smoking (OR, 1.0; 95% CI, 0.8-1.3) and TGCT risk. Although living with a non-parent smoker was marginally related to risk (OR, 1.4; 95% CI, 1.0-2.1), there was no relationship with number of smokers, amount smoked, or duration of smoking. Responses from both case-control participants and mothers also revealed no relationship between either maternal smoking while pregnant or while breast-feeding. Results did not differ by TGCT histology (seminoma, non-seminoma). These results do not support the hypothesis that passive smoking, either in utero or in childhood, is related to risk of TGCT. Other early life exposures, however, may explain the familial clustering of lung cancer in mothers and TGCT in sons.

  15. Specification of primordial germ cells in medaka (Oryzias latipes

    Directory of Open Access Journals (Sweden)

    Raz Erez

    2007-01-01

    Full Text Available Abstract Background Primordial germ cells (PGCs give rise to gametes that are responsible for the development of a new organism in the next generation. Two modes of germ line specification have been described: the inheritance of asymmetrically-localized maternally provided cytoplasmic determinants and the induction of the PGC fate by other cell types. PGCs specification in zebrafish appears to depend on inheritance of germ plasm in which several RNA molecules such as vasa and nanos reside. Whether the specification mode of PGCs found in zebrafish is general for other fish species was brought into question upon analysis of olvas expression – the vasa homologue in another teleost, medaka (Oryzias latipes. Here, in contrast to the findings in zebrafish, the PGCs are found in a predictable position relative to a somatic structure, the embryonic shield. This finding, coupled with the fact that vasa mRNA, which is localized to the germ plasm of zebrafish but does not label a similar structure in medaka opened the possibility of fundamentally different mechanisms governing PGC specification in these two fish species. Results In this study we addressed the question concerning the mode of PGC specification in medaka using embryological experiments, analysis of RNA stability in the PGCs and electron microscopy observations. Dramatic alterations in the somatic environment, i.e. induction of a secondary axis or mesoderm formation alteration, did not affect the PGC number. Furthermore, the PGCs of medaka are capable of protecting specific RNA molecules from degradation and could therefore exhibit a specific mRNA expression pattern controlled by posttrancriptional mechanisms. Subsequent analysis of 4-cell stage medaka embryos using electron microscopy revealed germ plasm-like structures located at a region corresponding to that of zebrafish germ plasm. Conclusion Taken together, these results are consistent with the idea that in medaka the inheritance of

  16. Effect of Antioxidants and Apoptosis Inhibitors on Cryopreservation of Murine Germ Cells Enriched for Spermatogonial Stem Cells.

    Directory of Open Access Journals (Sweden)

    Seung-Jung Ha

    Full Text Available Spermatogonial stem cells (SSCs are germline stem cells that serve as the foundation of spermatogenesis to maintain fertility throughout a male's lifetime. To treat male infertility using stem cell banking systems and transplantation, it is important to be able to preserve SSCs for long periods of time. Therefore, this study was conducted to develop an optimal cryopreservation protocol for SSCs using antioxidants and apoptosis inhibitors in freezing medium. No differences were observed compared to controls when SSCs were cryopreserved in the presence of apoptosis inhibitors by themselves. However, mouse germ cells cryopreserved in basal medium containing the antioxidant hypotaurine (14 mM resulted in significantly greater proliferation potential and mitochondrial activity. Furthermore, treatment groups with combinations containing 200 mM trehalose and 14 mM hypotaurine showed higher proliferation rates compared to controls. In addition, several serum free conditions were evaluated for SSC cryopreservation. Treatment media containing 10% or 20% knockout serum replacement resulted in similar cryopreservation results compared to media containing FBS. SSC transplantation was also performed to confirm the functionality of SSCs frozen in 14 mM hypotaurine. Donor SSCs formed normal spermatogenic colonies and sperm in the recipient testis. These data indicate that inclusion of 14 mM hypotaurine in cryopreservation media is an effective way to efficiently cryopreserve germ cells enriched for SSCs and that knockout serum replacement can replace FBS in germ cell cryopreservation media.

  17. Cold/menthol TRPM8 receptors initiate the cold-shock response and protect germ cells from cold-shock-induced oxidation.

    Science.gov (United States)

    Borowiec, Anne-Sophie; Sion, Benoit; Chalmel, Frédéric; D Rolland, Antoine; Lemonnier, Loïc; De Clerck, Tatiana; Bokhobza, Alexandre; Derouiche, Sandra; Dewailly, Etienne; Slomianny, Christian; Mauduit, Claire; Benahmed, Mohamed; Roudbaraki, Morad; Jégou, Bernard; Prevarskaya, Natalia; Bidaux, Gabriel

    2016-09-01

    Testes of most male mammals present the particularity of being externalized from the body and are consequently slightly cooler than core body temperature (4-8°C below). Although, hypothermia of the testis is known to increase germ cells apoptosis, little is known about the underlying molecular mechanisms, including cold sensors, transduction pathways, and apoptosis triggers. In this study, using a functional knockout mouse model of the cold and menthol receptors, dubbed transient receptor potential melastatine 8 (TRPM8) channels, we found that TRPM8 initiated the cold-shock response by differentially modulating cold- and heat-shock proteins. Besides, apoptosis of germ cells increased in proportion to the cooling level in control mice but was independent of temperature in knockout mice. We also observed that the rate of germ cell death correlated positively with the reactive oxygen species level and negatively with the expression of the detoxifying enzymes. This result suggests that the TRPM8 sensor is a key determinant of germ cell fate under hypothermic stimulation.-Borowiec, A.-S., Sion, B., Chalmel, F., Rolland, A. D., Lemonnier, L., De Clerck, T., Bokhobza, A., Derouiche, S., Dewailly, E., Slomianny, C., Mauduit, C., Benahmed, M., Roudbaraki, M., Jégou, B., Prevarskaya, N., Bidaux, G. Cold/menthol TRPM8 receptors initiate the cold-shock response and protect germ cells from cold-shock-induced oxidation. © The Author(s).

  18. Immunofluorescence Analysis of Testicular Biopsies With Germ Cell and Sertoli Cell Markers Shows Significant MVH Negative Germ Cell Depletion With Older Age of Orchidopexy

    DEFF Research Database (Denmark)

    Li, Ruili; Thorup, Jørgen Mogens; Sun, Cong

    2014-01-01

    Undescended testis is the most common defect in newborn boys. It is associated with increased risks of infertility and testicular malignancy due to abnormal germ cell development in these testes. Early surgery may limit such risks. The aim of our study was to analyse germ cell development verses ...... age of orchidopexy using a germ cell marker and a Sertoli cell marker on testicular biopsies.......Undescended testis is the most common defect in newborn boys. It is associated with increased risks of infertility and testicular malignancy due to abnormal germ cell development in these testes. Early surgery may limit such risks. The aim of our study was to analyse germ cell development verses...

  19. Nuclear Reprogramming in Mouse Primordial Germ Cells: Epigenetic Contribution

    Directory of Open Access Journals (Sweden)

    Massimo De Felici

    2011-01-01

    Full Text Available The unique capability of germ cells to give rise to a new organism, allowing the transmission of primary genetic information from generation to generation, depends on their epigenetic reprogramming ability and underlying genomic totipotency. Recent studies have shown that genome-wide epigenetic modifications, referred to as “epigenetic reprogramming”, occur during the development of the gamete precursors termed primordial germ cells (PGCs in the embryo. This reprogramming is likely to be critical for the germ line development itself and necessary to erase the parental imprinting and setting the base for totipotency intrinsic to this cell lineage. The status of genome acquired during reprogramming and the associated expression of key pluripotency genes render PGCs susceptible to transform into pluripotent stem cells. This may occur in vivo under still undefined condition, and it is likely at the origin of the formation of germ cell tumors. The phenomenon appears to be reproduced under partly defined in vitro culture conditions, when PGCs are transformed into embryonic germ (EG cells. In the present paper, I will try to summarize the contribution that epigenetic modifications give to nuclear reprogramming in mouse PGCs.

  20. ATTEMPT TO APPLY STABILIZED WHEAT GERM FOR BREAD SUPPLEMENTATION

    Directory of Open Access Journals (Sweden)

    Halina Gambuś

    2015-02-01

    Full Text Available The increased interest in rational nutrition causes, that from many years is observed a growing consumption of bread, and novel food supplemented with health promoting components. For the bread production in Poland mainly wheat and rye cake flours are used, depleted of a many valuable nutrients such as protein, dietary fibre, minerals and vitamins. Because of their unique chemical composition wheat germs are a particularly valuable resource, both for direct consumption and to enhance the nutritional value of food products. The aim of the study was to prepare wheat bread with a 10% addition of commercial stabilized wheat germs. Based on the obtained results, it was found that wheat germs, due to their unique chemical composition, were a particularly valuable resource to supplement the nutritional value of bread. However, germs had detrimental effect on mechanical properties of dough, and on bread quality. Texture of bread crumb and its chemical composition were analysed. It was shown, that germs subjected to fermentation process could be used in wheat bread production as dietary fibre and mineral compound supplement.

  1. Conserved and divergent patterns of expression of DAZL, VASA and OCT4 in the germ cells of the human fetal ovary and testis

    Directory of Open Access Journals (Sweden)

    Coutts Shona

    2007-12-01

    Full Text Available Abstract Background Germ cells arise from a small group of cells that express markers of pluripotency including OCT4. In humans formation of gonadal compartments (cords in testis, nests in ovary takes place during the 1st trimester (6–8 weeks gestation. In the 2nd trimester germ cells can enter meiotic prophase in females whereas in males this does not occur until puberty. We have used qRTPCR, Westerns and immunohistochemical profiling to determine which of the germ cell subtypes in the human fetal gonads express OCT4, DAZL and VASA, as these have been shown to play an essential role in germ cell maturation in mice. Results OCT4 mRNA and protein were detected in extracts from both 1st and 2nd trimester ovaries and testes. In ovarian extracts a marked increase in expression of VASA and DAZL mRNA and protein occurred in the 2nd trimester. In testicular extracts VASA mRNA and protein were low/undetectable in 1st trimester and increased in the 2nd trimester whereas the total amount of DAZL did not seem to change. During the 1st trimester, germ cells were OCT4 positive but did not express VASA. These results are in contrast to the situation in mice where expression of Vasa is initiated in Oct4 positive primordial germ cells as they enter the gonadal ridge. In the 2nd trimester germ cells with intense cytoplasmic staining for VASA were present in both sexes; these cells were OCT4 negative. DAZL expression overlapped with both OCT4 and VASA and changed from the nuclear to the cytoplasmic compartment as cells became OCT4-negative. In males, OCT4-positive and VASA-positive subpopulations of germ cells coexisted within the same seminiferous cords but in the ovary there was a distinct spatial distribution of cells with OCT4 expressed by smaller, peripherally located, germ cells whereas DAZL and VASA were immunolocalised to larger (more mature centrally located cells. Conclusion OCT4, DAZL and VASA are expressed by human fetal germ cells but their

  2. Male fertility preservation before gonadotoxic therapies

    OpenAIRE

    Wyns, C.

    2010-01-01

    Background: Recent advances in cancer therapy have resulted in an increased number of long-term cancer survivors. Unfortunately, aggressive chemotherapy, radiotherapy and preparative regimens for bone marrow transplantation can severely affect male germ cells, including spermatogonial stem cells (SSCs), and lead to permanent loss of fertility. Different options for fertility preservation are dependent on the pubertal state of the patient. Methods: Relevant studies were identified by an extens...

  3. An in vitro, short-term culture method for mammalian haploid round spermatids amenable for molecular manipulation.

    Science.gov (United States)

    Dehnugara, Tushna; Dhar, Surbhi; Rao, M R Satyanarayana

    2012-01-01

    Extensive chromatin remodeling is a characteristic feature of mammalian spermiogenesis. To date, methods for the molecular manipulation of haploid spermatids are not available as there is a lack of a well-established culture system. Biochemical experiments and knockout studies reveal only the final outcome; studying the incremental details of the intricate mechanisms involved is still a challenge. We have established an in vitro culture system for pure haploid round spermatids isolated from rat testes that can be maintained with good viability for up to 72 hr. Changes in cell morphology and flagellar growth were also studied in the cultured spermatids. Further, we have demonstrated that upon treatment of cells with specific histone deacetylase inhibitors, sodium butyrate and trichostatin A, there is an increase in the hyperacetylation status of histone H4, mimicking an important event characteristic of histone replacement process that occurs during later stages of spermiogenesis. We have also tried various methods for introducing DNA and protein into these round spermatids in culture, and report that while DNA transfection is still a challenging task, protein transfection could be achieved using Chariot™ peptide as a transfection reagent. Thus, the method described here sets a stage to study the molecular roles of spermatid-specific proteins and chromatin remodelers in the cellular context. Copyright © 2011 Wiley Periodicals, Inc.

  4. Standing at the Gateway to Europe - The Genetic Structure of Western Balkan Populations Based on Autosomal and Haploid Markers

    Science.gov (United States)

    Kovacevic, Lejla; Tambets, Kristiina; Ilumäe, Anne-Mai; Kushniarevich, Alena; Yunusbayev, Bayazit; Solnik, Anu; Bego, Tamer; Primorac, Dragan; Skaro, Vedrana; Leskovac, Andreja; Jakovski, Zlatko; Drobnic, Katja; Tolk, Helle-Viivi; Kovacevic, Sandra; Rudan, Pavao; Metspalu, Ene; Marjanovic, Damir

    2014-01-01

    Contemporary inhabitants of the Balkan Peninsula belong to several ethnic groups of diverse cultural background. In this study, three ethnic groups from Bosnia and Herzegovina - Bosniacs, Bosnian Croats and Bosnian Serbs - as well as the populations of Serbians, Croatians, Macedonians from the former Yugoslav Republic of Macedonia, Montenegrins and Kosovars have been characterized for the genetic variation of 660 000 genome-wide autosomal single nucleotide polymorphisms and for haploid markers. New autosomal data of the 70 individuals together with previously published data of 20 individuals from the populations of the Western Balkan region in a context of 695 samples of global range have been analysed. Comparison of the variation data of autosomal and haploid lineages of the studied Western Balkan populations reveals a concordance of the data in both sets and the genetic uniformity of the studied populations, especially of Western South-Slavic speakers. The genetic variation of Western Balkan populations reveals the continuity between the Middle East and Europe via the Balkan region and supports the scenario that one of the major routes of ancient gene flows and admixture went through the Balkan Peninsula. PMID:25148043

  5. Standing at the gateway to Europe--the genetic structure of Western balkan populations based on autosomal and haploid markers.

    Science.gov (United States)

    Kovacevic, Lejla; Tambets, Kristiina; Ilumäe, Anne-Mai; Kushniarevich, Alena; Yunusbayev, Bayazit; Solnik, Anu; Bego, Tamer; Primorac, Dragan; Skaro, Vedrana; Leskovac, Andreja; Jakovski, Zlatko; Drobnic, Katja; Tolk, Helle-Viivi; Kovacevic, Sandra; Rudan, Pavao; Metspalu, Ene; Marjanovic, Damir

    2014-01-01

    Contemporary inhabitants of the Balkan Peninsula belong to several ethnic groups of diverse cultural background. In this study, three ethnic groups from Bosnia and Herzegovina - Bosniacs, Bosnian Croats and Bosnian Serbs - as well as the populations of Serbians, Croatians, Macedonians from the former Yugoslav Republic of Macedonia, Montenegrins and Kosovars have been characterized for the genetic variation of 660 000 genome-wide autosomal single nucleotide polymorphisms and for haploid markers. New autosomal data of the 70 individuals together with previously published data of 20 individuals from the populations of the Western Balkan region in a context of 695 samples of global range have been analysed. Comparison of the variation data of autosomal and haploid lineages of the studied Western Balkan populations reveals a concordance of the data in both sets and the genetic uniformity of the studied populations, especially of Western South-Slavic speakers. The genetic variation of Western Balkan populations reveals the continuity between the Middle East and Europe via the Balkan region and supports the scenario that one of the major routes of ancient gene flows and admixture went through the Balkan Peninsula.

  6. "Mixed germ cell testicular tumor" in an adult female

    Directory of Open Access Journals (Sweden)

    Udasimath Shivakumarswamy

    2012-01-01

    Full Text Available The androgen insensitivity (testicular feminization syndrome was described by Morris in phenotypic females with 46XY karyotype, presenting with primary amenorrhea, adequate breast development, and absent or scanty pubic or axillary hair. Gonads consist usually of seminiferous tubules without spermatogenesis. These patients have a 5-10% risk of developing germ cell tumors, usually after the complete development of secondary female sexual characteristics. We hereby report a case considered as a female with married life of 15 years, who was operated for severe abdominal pain. Phenotype characters were that of female. Microscopic examination of the tumor from the abdomen revealed germinoma and yolk sac tumor with adjacent seminiferous tubules. Karyotyping showed 46XY. Final diagnosis of malignant mixed germ cell tumor in androgen insensitivity syndrome was made. Surveillance may be the most appropriate option when these conditions are initially diagnosed in adulthood to prevent development of germ cell tumors.

  7. Germ cell neoplasia in situ (GCNIS)

    DEFF Research Database (Denmark)

    Berney, Daniel M; Looijenga, Leendert H J; Idrees, Muhammad

    2016-01-01

    The pre-invasive lesion associated with post-pubertal malignant germ cell tumours of the testis was first recognized in the early 1970s and confirmed by a number of observational and follow-up studies. Until this year, this scientific story has been confused by resistance to the entity and disagr......The pre-invasive lesion associated with post-pubertal malignant germ cell tumours of the testis was first recognized in the early 1970s and confirmed by a number of observational and follow-up studies. Until this year, this scientific story has been confused by resistance to the entity...... and disagreement on its name. Initially termed 'carcinoma in situ' (CIS), it has also been known as 'intratubular germ cell neoplasia, unclassified' (IGCNU) and 'testicular intraepithelial neoplasia' (TIN). In this paper, we review the history of discovery and controversy concerning these names and introduce...

  8. Germ-line gene therapy and the medical imperative.

    Science.gov (United States)

    Munson, Ronald; Davis, Lawrence H

    1992-06-01

    Somatic cell gene therapy has yielded promising results. If germ cell gene therapy can be developed, the promise is even greater: hundreds of genetic diseases might be virtually eliminated. But some claim the procedure is morally unacceptable. We thoroughly and sympathetically examine several possible reasons for this claim but find them inadequate. There is no moral reason, then, not to develop and employ germ-line gene therapy. Taking the offensive, we argue next that medicine has a prima facie moral obligation to do so.

  9. Reduction of the number of germs in spices by radappertization

    International Nuclear Information System (INIS)

    Beczner, Laszlone; Kiss, Istvan

    1983-01-01

    The sterilization by fumigation with ethylene oxide and propylene oxide of ground paprika and spice mixtures used in preserves and meat industry was compared with the radappertization of the same spices. The number of germs including that of spores and moulds was determined. It can be established that irradiation with ionizing radiation (5 kGy) has the same effect on the reduction of the number of germs as sterilization by ethylene oxide. In addition, the side effects of sterilization can be avoided. (V.N.)

  10. Radiation-induced genetic effects in germ cells of mammals

    International Nuclear Information System (INIS)

    Van der Schans, G.P.

    1993-01-01

    The objectives of the project are a better understanding of the fundamental principles that determine the radiation sensitivity in humans, with specific attention for the role of DNA repair in germ cells. The induction and repair of damage in DNA of germ cells of the Syrian golden hamster exposed to ionizing radiation is studied at biologically relevant doses. It has also been investigated which aspects of DNA sequence or chromosomal organisation are important with respect to their influence on the repairability of DNA damage. (R.P.) 10 refs

  11. Coffee mitigates cyclophosphamide-induced genotoxic damage in Drosophila melanogaster germ cells.

    Science.gov (United States)

    Nagpal, Isha; Abraham, Suresh K

    2018-02-26

    In the present study, coffee (CF) was evaluated for its protective effects against genotoxic damage and oxidative stress induced by the chemotherapeutic drug, cyclophosphamide (CPH). The sex-linked recessive lethal (SLRL) test was employed to study the induction of mutations in the larvae as well as in all the successive germ cell stages of treated males. Control and treated third instar larvae were used to monitor the biomarkers of oxidative stress response such as glutathione content (GSH), glutathione-S-transferase (GST), catalase (CAT), superoxide dismutase (SOD) and lipid peroxidation (MDA content). Our results demonstrated that co-administration of CF (2%) with CPH (3 mM) has significantly reduced CPH-induced lethal mutations in the germ cells of larvae and adult flies. The reductions observed in mutation frequencies were: 75% in larvae and 62.4% in the adult. Significant enhancement in antioxidant enzymatic levels: CAT (46.6%) > SOD (43.0%) > GST (42.4%) > GSH (31.6%) and reduction in MDA levels (32.05%) in the pretreated third instar larvae demonstrated the antioxidant activity of CF against CPH-induced oxidative stress. The findings from the present study suggest that the Drosophila model is an ideal one for evaluating the antigenotoxic and antioxidant activity of complex mixtures like CF.

  12. Strategies for implementing genomic selection in family-based aquaculture breeding schemes: double haploid sib test populations

    Directory of Open Access Journals (Sweden)

    Nirea Kahsay G

    2012-10-01

    Full Text Available Abstract Background Simulation studies have shown that accuracy and genetic gain are increased in genomic selection schemes compared to traditional aquaculture sib-based schemes. In genomic selection, accuracy of selection can be maximized by increasing the precision of the estimation of SNP effects and by maximizing the relationships between test sibs and candidate sibs. Another means of increasing the accuracy of the estimation of SNP effects is to create individuals in the test population with extreme genotypes. The latter approach was studied here with creation of double haploids and use of non-random mating designs. Methods Six alternative breeding schemes were simulated in which the design of the test population was varied: test sibs inherited maternal (Mat, paternal (Pat or a mixture of maternal and paternal (MatPat double haploid genomes or test sibs were obtained by maximum coancestry mating (MaxC, minimum coancestry mating (MinC, or random (RAND mating. Three thousand test sibs and 3000 candidate sibs were genotyped. The test sibs were recorded for a trait that could not be measured on the candidates and were used to estimate SNP effects. Selection was done by truncation on genome-wide estimated breeding values and 100 individuals were selected as parents each generation, equally divided between both sexes. Results Results showed a 7 to 19% increase in selection accuracy and a 6 to 22% increase in genetic gain in the MatPat scheme compared to the RAND scheme. These increases were greater with lower heritabilities. Among all other scenarios, i.e. Mat, Pat, MaxC, and MinC, no substantial differences in selection accuracy and genetic gain were observed. Conclusions In conclusion, a test population designed with a mixture of paternal and maternal double haploids, i.e. the MatPat scheme, increases substantially the accuracy of selection and genetic gain. This will be particularly interesting for traits that cannot be recorded on the

  13. File list: Oth.Gon.20.AllAg.Testicular_germ_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Gon.20.AllAg.Testicular_germ_cells mm9 TFs and others Gonad Testicular germ cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Gon.20.AllAg.Testicular_germ_cells.bed ...

  14. File list: Oth.Gon.10.AllAg.Testicular_germ_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Gon.10.AllAg.Testicular_germ_cells mm9 TFs and others Gonad Testicular germ cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Gon.10.AllAg.Testicular_germ_cells.bed ...

  15. File list: Pol.Gon.05.AllAg.Testicular_germ_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Gon.05.AllAg.Testicular_germ_cells mm9 RNA polymerase Gonad Testicular germ cel...ls http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.Gon.05.AllAg.Testicular_germ_cells.bed ...

  16. File list: DNS.Gon.05.AllAg.Testicular_germ_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Gon.05.AllAg.Testicular_germ_cells mm9 DNase-seq Gonad Testicular germ cells ht...tp://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Gon.05.AllAg.Testicular_germ_cells.bed ...

  17. Adult Immunohistochemical Markers Fail to Detect Intratubular Germ Cell Neoplasia in Prepubertal Boys with Cryptorchidism

    DEFF Research Database (Denmark)

    Kvist, Kolja; Clasen-Linde, Erik; Cortes, Dina

    2013-01-01

    Intratubular germ cell neoplasia (ITGCN) is a precursor to testicular germ cell cancer. It is characterized by large germ cells with large nuclei with a hyperchromatic, coarse chromatin pattern, large prominent nucleoli and abundant pale cytoplasm. In prepubertal boys these cells are located both...

  18. Great migration: epigenetic reprogramming and germ cell-oocyte metamorphosis determine individual ovarian reserve.

    Science.gov (United States)

    Celik, Onder; Aygun, Banu Kumbak; Celik, Nilufer; Aydin, Suleyman; Haberal, Esra Tustas; Sahin, Levent; Yavuz, Yasemin; Celik, Sudenaz

    2016-01-01

    Emigration is defined as a synchronized movement of germ cells between the yolk sack and genital ridges. The miraculous migration of germ cells resembles the remigration of salmon traveling from one habitat to other. This migration of germ cells is indispensible for the development of new generations. It is not, however, clear why germ cells differentiate during migration but not at the place of origin. In order to escape harmful somatic signals which might disturb the proper establishment of germ cells forced germ cell migration may be necessary. Another reason may be to benefit from the opportunities of new habitats. Therefore, emigration may have powerful effects on the population dynamics of the immigrant germ cells. While some of these cells do reach their target, some others die or reach to wrong targets. Only germ cell precursors with genetically, and structurally powerful can reach their target. Likewise, epigenetic reprogramming in both migratory and post-migratory germ cells is essential for the establishment of totipotency. During this journey some germ cells may sacrifice themselves for the goodness of the others. The number and quality of germ cells reaching the genital ridge may vary depending on the problems encountered during migration. If the aim in germ cell specification is to provide an optimal ovarian reserve for the continuity of the generation, then this cascade of events cannot be only accomplished at the same level for every one but also are manifested by several outcomes. This is significant evidence supporting the possibility of unique individual ovarian reserve.

  19. Carcinoma in situ testis displays permissive chromatin modifications similar to immature foetal germ cells

    DEFF Research Database (Denmark)

    Almstrup, K; Nielsen, J E; Mlynarska, O

    2010-01-01

    The majority of testicular germ cell cancers develop through a pre-invasive carcinoma in situ (CIS) stage. The CIS cell is a neoplastic counterpart of foetal germ cells. During their development, foetal germ cells undergo extensive and essential epigenetic modifications, but little is known about...

  20. Childhood Central Nervous System Germ Cell Tumors Treatment (PDQ®)—Patient Version

    Science.gov (United States)

    Childhood central nervous system (CNS) germ cell tumors form from germ cells (a type of cell that forms as a fetus develops and later becomes sperm in the testicles or eggs in the ovaries). Learn about the signs, tests to diagnose, and treatment of pediatric germ cell tumors in the brain in this expert-reviewed summary.

  1. Some characteristics and its influence factors of chromosome aberrations of germ cells induced by ionizing radiation in mice

    International Nuclear Information System (INIS)

    Jin Yuke; Cai Lu; Wang Xianli

    1995-01-01

    The chromosome aberrations of germ cells in mice by low LET ionizing radiation were systematically studied. The study demonstrated that the chromosome aberrations were linear or linearly square correlated with X-ray doses in large doses; that was linear correlated with X-ray doses in low doses. In addition, there were many factors directly influencing chromosome aberrations. The aberrations of the germ cells in males were 4.4 times of that in females. The aberrations in the germ cells were significantly higher after meiosis than before. The aberrations in secondary spermatocytes were 3.6 times of that in spermatogonia and 10 times of that in primary spermatocytes, respectively. In different phases of meiosis, the amount of chromosome aberrations in leptotene was the least, that in diaknesis was the most. The spermatogonic translocation rate receiving a whole body X-irradiation was 1.74 times of that receiving a local testis X-irradiation. The spermatogonic translocation rate of acute X-irradiation was 4.6∼6.3 times of that of chronic γ-irradiation

  2. GAGE cancer-germline antigens bind DNA and are recruited to the nuclear envelope by Germ cell-less

    DEFF Research Database (Denmark)

    Gjerstorff, Morten; Rösner, Heike; Pedersen, Christina Bøg

    GAGE genes encode a highly similar, primate-specific protein family with unique primary structure and undefined roles in germ cells, various fetal cells and cancer cells. We report that GAGE proteins are intrinsically disordered proteins that provide novel interfaces between chromatin and the nuc......GAGE genes encode a highly similar, primate-specific protein family with unique primary structure and undefined roles in germ cells, various fetal cells and cancer cells. We report that GAGE proteins are intrinsically disordered proteins that provide novel interfaces between chromatin...... and the nuclear envelope. Structural analysis by NMR and CD spectroscopy showed GAGE proteins lack distinct secondary or tertiary structure and are therefore intrinsically disordered. In normal cells and cancer cells GAGE proteins localize predominantly in the nucleus; we found GAGE proteins formed stable......) at the nuclear envelope. Furthermore, exogenous and endogenous GAGE proteins were recruited to the nuclear envelope in GCL-overexpressing cells. Gene expression analysis and immunohistochemical staining suggest GAGE proteins and GCL interact physiologically in human cells that express both, including male germ...

  3. Molecular mechanisms governing primordial germ cell migration in zebrafish

    NARCIS (Netherlands)

    Doitsidou, M.

    2005-01-01

    In most sexually reproducing organisms primordial germ cells (pGCs) are specified early in development in places that are distinct from the region where the somatic part of the gonad develops. From their places of specification they have to migrate towards the site where they associate with somatic

  4. Stability of wheat germ oil obtained by supercritical carbon dioxide ...

    African Journals Online (AJOL)

    심정은

    For determination of stability, wheat germ oil obtained by ethanolysis reactants was characterized by ... extract non polar lipids with lipid soluble bioactive com- pounds from different sources (Esquivel et al., 1997; ... thin layer of cotton was placed at the bottom of the extraction vessel. Before plugging with cap another layer of ...

  5. Genetic analysis of neonatal and infantile germ cell tumours.

    NARCIS (Netherlands)

    Veltman, I.M.

    2006-01-01

    Human germ cell tumours (GCTs) can be classified into five distinct types, based on differences in anatomical location, histology, clinical outcome, age and genotype. The first type, the type I GCTs primarily occur in neonates and infants under the age of five years and include teratomas and yolk

  6. Germ cell tumours in neonates and infants: a distinct subgroup?

    NARCIS (Netherlands)

    Veltman, I.M.; Schepens, M.T.M.; Looijenga, L.H.J.; Strong, L.C.; Geurts van Kessel, A.H.M.

    2003-01-01

    Human germ cell tumours (GCTs) constitute a heterogeneous group of tumours that can be classified into four major subgroups. One of these subgroups encompasses (immature) teratomas and yolk sac tumours of patients under the age of 5 years. In this paper we review the various clinical, histological

  7. Treatment Options for Childhood Extracranial Germ Cell Tumors

    Science.gov (United States)

    ... tumors: Yolk sac tumors make a hormone called alpha-fetoprotein (AFP). They can form in the ovary, testicle, ... are used to detect extracranial germ cell tumors: Alpha-fetoprotein (AFP). Beta-human chorionic gonadotropin (β-hCG). For ...

  8. General Information about Childhood Extracranial Germ Cell Tumors

    Science.gov (United States)

    ... tumors: Yolk sac tumors make a hormone called alpha-fetoprotein (AFP). They can form in the ovary, testicle, ... are used to detect extracranial germ cell tumors: Alpha-fetoprotein (AFP). Beta-human chorionic gonadotropin (β-hCG). For ...

  9. Dynamics of germs responsible for acute bacterial meningitis in ...

    African Journals Online (AJOL)

    The aim of this study was to analyze ten (10) years of epidemiological surveillance data of meningitis in Burkina Faso for high risk germs patterns identification in order to contribute to the strengthening of prevention strategies. A retrospective study of the past decade (2005- 2014) of cases of acute bacterial meningitis ...

  10. 10 original article dynamics of germs responsible for acute bacterial ...

    African Journals Online (AJOL)

    boaz

    The aim of this study was to analyze ten (10) years of epidemiological surveillance data of meningitis in Burkina Faso for high risk germs patterns identification in order to contribute to the strengthening of prevention strategies. A retrospective study of the past decade (2005- 2014) of cases of acute bacterial meningitis ...

  11. Wheat Germ Oil Attenuates Gamma Radiation-Induced Skeletal ...

    African Journals Online (AJOL)

    Muscular strength is important in sport as well as in daily activities. Exposure to ionizing radiation is thought to increase oxidative stress and damage muscle tissue. Wheat germ oil is a natural unrefined vegetable oil. It is an excellent source of vitamin E, octacosanol, linoleic and linolenic essential fatty acids, which may be ...

  12. Towards Optimal Diagnosis of Type II Germ Cell Tumors

    NARCIS (Netherlands)

    J.A. Stoop (Hans)

    2011-01-01

    textabstractThe aim of the work described in this thesis is to improve the understanding of the pathobiology of testicular cancer (type II Germ Cell Tumors) to create possibilities for optimalization of diagnosis for this type of malignancy in routine pathology laboratories. The different studies

  13. Clinical and genetic aspects of testicular germ cell tumours

    NARCIS (Netherlands)

    Holzik, Martijn F. Lutke; Sijmons, Rolf H.; Hoekstra-Weebers, Josette E. H. M.; Sleijfer, Dirk Th.; Hoekstra, Harald J.

    2008-01-01

    In this paper we review clinical and genetic aspects of testicular germ cell tumours (TGCTs). TGCT is the most common type of malignant disorder in men aged 15-40 years. Its incidence has increased sharply in recent years. Fortunately, survival of patients with TGCT has improved enormously, which

  14. A comparison between hominy chop and defatted maize germ meal ...

    African Journals Online (AJOL)

    Defatted maize germ meal (DMG) is arbitrarily rated at a lower economic value than maize meal or hominy chop (HC). Five treatments with 15 steers each were fed different inclusion levels of DMG (0%, 25%, 50%, 75% and 100%), replacing hominy chop during the fattening period. Slaughter data were collected for carcass ...

  15. Hybrid male sterility is caused by mitochondrial DNA deletion.

    Science.gov (United States)

    Hayashida, Kenji; Kohno, Shigeru

    2009-07-01

    Although it is known that the hybrid male mouse is sterile just like any other animal's heterogametic sex, the reason why only the male germ cells are impaired has yet to be discovered. TdT-mediated dUTP nick end labeling assay using a confocal fluorescence microscope and DNA fragmentation assay of hybrid testis indicated destruction of the mitochondrial DNA (mtDNA) rather than the nuclear DNA. Previously we reported that maternal mtDNA inheritance is through selective sperm mtDNA elimination based on the sperm factor and two egg factors, and expression of these three factors was recognized in the hybrid testis. It was thereby assumed that mtDNA destruction caused by the expression of maternal mtDNA inheritance system in male germ cells is implicated in the hybrid male sterility of mice.

  16. Genome Sequences of Industrially Relevant Saccharomyces cerevisiae Strain M3707, Isolated from a Sample of Distillers Yeast and Four Haploid Derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Steven D.; Klingeman, Dawn M.; Johnson, Courtney M.; Clum, Alicia; Aerts, Andrea; Salamov, Asaf; Sharma, Aditi; Zane, Matthew; Barry, Kerrie; Grigoriev, Igor V.; Davison, Brian H.; Lynd, Lee R.; Gilna, Paul; Hau, Heidi; Hogsett, David A.; Froehlich, Allan C.

    2013-04-19

    Saccharomyces cerevisiae strain M3707 was isolated from a sample of commercial distillers yeast, and its genome sequence together with the genome sequences for the four derived haploid strains M3836, M3837, M3838, and M3839 has been determined. Yeasts have potential for consolidated bioprocessing (CBP) for biofuel production, and access to these genome sequences will facilitate their development.

  17. Obtaining apple haploid plants (Malus X domestica Borkh.) from in situ parthenogenesis induced by irradiated pollen and in vitro culture of immature seeds

    International Nuclear Information System (INIS)

    Zhang, Y.X.; Lespinasse, Y.; Chevreau, E.

    1988-01-01

    Two apple varieties, ''Erovan'' and ''Lodi'', have been pollinated with pollen carrying the marker gene R irradiated by gamma rays from Cobalt 60 with doses of 500, 1000 and 1500 Gy. By in vitro cultures of the immature seeds removed 7 to 13 weeks after pollination, haploid plants (2n=x=17) have been obtained from ''Erovan'' [fr

  18. Plant regeneration from haploid cell suspension-derived protoplasts of Mediterranean rice (Oryza sativa L. cv. Miara).

    Science.gov (United States)

    Guiderdoni, E; Chaïr, H

    1992-11-01

    More than 750 plants were regenerated from protoplasts isolated from microspore callus-derived cell suspensions of the Mediterranean japonica rice Miara, using a nurse-feeder technique and N6-based culture medium. The mean plating efficiency and the mean regeneration ability of the protocalluses were 0.5% and 49% respectively. Flow cytometric evaluation of the DNA contents of 7 month old-cell and protoplast suspensions showed that they were still haploid. Contrastingly, the DNA contents of leaf cell nuclei of the regenerated protoclones ranged from 1C to 5C including 60% 2C plants. This was consistent with the morphological type and the fertility of the mature plants. These results and the absence of chimeric plants suggest that polyploidization occurred during the early phase of protoplast culture.

  19. Successful xenogeneic germ cell transplantation from Jundia catfish (Rhamdia quelen) into adult Nile tilapia (Oreochromis niloticus) testes.

    Science.gov (United States)

    Silva, M A; Costa, G M J; Lacerda, S M S N; Brandão-Dias, P F P; Kalapothakis, E; Silva Júnior, A F; Alvarenga, E R; França, L R

    2016-05-01

    Fish germ cell transplantation presents several important potential applications for aquaculture, including the preservation of germplasm from endangered fish species with high genetic and commercial values. Using this technique in studies developed in our laboratory with adult male Nile tilapias (Oreochromis niloticus), all the necessary procedures were successfully established, allowing the production of functional sperm and healthy progeny approximately 2months after allogeneic transplantation. In the present study, we evaluated the viability of the adult Nile tilapia testis to generate sperm after xenogeneic transplant of germ cells from sexually mature Jundia catfish (Rhamdia quelen) that belong to a different taxonomic order. Therefore, in order to investigate at different time-periods post-transplantation, the presence and development of donor PKH26 labeled catfish germ cells were followed in the tilapia seminiferous tubules. From 7 to 20days post-transplantation, only PKH26 labeled spermatogonia were observed, whereas spermatocytes at different stages of development were found at 70days. Germ cell transplantation success and progression of spermatogenesis were indicated by the presence of labeled PKH26 spermatids and sperm on days 90 and 120 post-transplantation, respectively. Confirming the presence of the catfish genetic material in the tilapia testis, all recipient tilapias evaluated (n=8) showed the genetic markers evaluated. Therefore, we demonstrated for the first time that the adult Nile tilapia testis offers the functional conditions for development of spermatogenesis with sperm production from a fish species belonging to a different order, which provides an important new venue for aquaculture advancement. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Simulation and estimation of gene number in a biological pathway using almost complete saturation mutagenesis screening of haploid mouse cells.

    Science.gov (United States)

    Tokunaga, Masahiro; Kokubu, Chikara; Maeda, Yusuke; Sese, Jun; Horie, Kyoji; Sugimoto, Nakaba; Kinoshita, Taroh; Yusa, Kosuke; Takeda, Junji

    2014-11-24

    Genome-wide saturation mutagenesis and subsequent phenotype-driven screening has been central to a comprehensive understanding of complex biological processes in classical model organisms such as flies, nematodes, and plants. The degree of "saturation" (i.e., the fraction of possible target genes identified) has been shown to be a critical parameter in determining all relevant genes involved in a biological function, without prior knowledge of their products. In mammalian model systems, however, the relatively large scale and labor intensity of experiments have hampered the achievement of actual saturation mutagenesis, especially for recessive traits that require biallelic mutations to manifest detectable phenotypes. By exploiting the recently established haploid mouse embryonic stem cells (ESCs), we present an implementation of almost complete saturation mutagenesis in a mammalian system. The haploid ESCs were mutagenized with the chemical mutagen N-ethyl-N-nitrosourea (ENU) and processed for the screening of mutants defective in various steps of the glycosylphosphatidylinositol-anchor biosynthetic pathway. The resulting 114 independent mutant clones were characterized by a functional complementation assay, and were shown to be defective in any of 20 genes among all 22 known genes essential for this well-characterized pathway. Ten mutants were further validated by whole-exome sequencing. The predominant generation of single-nucleotide substitutions by ENU resulted in a gene mutation rate proportional to the length of the coding sequence, which facilitated the experimental design of saturation mutagenesis screening with the aid of computational simulation. Our study enables mammalian saturation mutagenesis to become a realistic proposition. Computational simulation, combined with a pilot mutagenesis experiment, could serve as a tool for the estimation of the number of genes essential for biological processes such as drug target pathways when a positive selection of

  1. International germ cell consensus classification : A prognostic factor-erased staging system for metastatic germ cell cancers

    NARCIS (Netherlands)

    Mead, GM; Stenning, SP; Cook, P; Fossa, SD; Horwich, A; Kaye, SB; Oliver, RTD; deMulder, PHM; deWit, R; Stoter, G; Sylvester, RJ; Bajorin, DF; Bosl, GJ; Mazumdar, M; Nichols, CR; Amato, R; Pizzocaro, G; Droz, JP; Kramar, A; Daugaard, G; CortesFunes, H; PazAres, L; Levi, JA; Colls, BM; Harvey, VJ; Coppin, C

    Purpose: Cisplatin-containing chemotherapy has dramatically improved the outlook for patients with metastatic germ cell tumors (GCT), and overall cure rates now exceed 80%. To make appropriate risk-based decisions about therapy and to facilitate collaborative trials, a simple prognostic factor-based

  2. NUT midline carcinoma mimicking a germ cell tumor: a case report

    International Nuclear Information System (INIS)

    Harada, Yohei; Koyama, Takafumi; Takeuchi, Kengo; Shoji, Kazufusa; Hoshi, Kazuei; Oyama, Yu

    2016-01-01

    NUT midline carcinoma (NMC) is a rare and highly aggressive malignancy. Although more information on NMC has been recently accumulating in the literature, most oncologists and pathologists remain unfamiliar with the clinical and pathologic features of this disease. The clinical features of NMC sometimes mimic those of other malignancies, and NMC can therefore be overlooked if the diagnosis is not suspected. We present the case of a young male with NMC arising in the mediastinum with elevated serum alpha-fetoprotein levels suggestive of an extragonadal nonseminomatous germ-cell tumor. A 28-year-old Japanese male presented with cough and left-sided chest pain for 6 weeks. The patient had a mediastinal tumor with metastases to the right lung, lymph nodes, and bones at initial presentation. Nonseminomatous germ cell tumor was suspected due to the young age, location of the tumors, and elevated serum alpha-fetoprotein. However, biopsy confirmed the diagnosis of NMC with immunohistochemistry. The tumor briefly responded to cytotoxic chemotherapy but subsequently progressed and became refractory to the chemotherapy regimen. External beam radiotherapy was administered with dramatic shrinkage of the tumor and a metabolic response on 18-fluoro-2-deoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) scan. However, the patient died 4.5 months after the diagnosis of NMC. Serum levels of alpha-fetoprotein may be elevated in patients with NMC. Regardless of the level of tumor markers, immunohistochemistry for NUT should be performed in cases of poorly differentiated carcinomas without glandular differentiation arising in the midline structures. 18 F-FDG PET/CT is useful for staging and assessing responses to therapy

  3. Chemical reproductive traits of diploid Bombus terrestris males: Consequences on bumblebee conservation.

    Science.gov (United States)

    Lecocq, Thomas; Gérard, Maxence; Maebe, Kevin; Brasero, Nicolas; Dehon, Lauren; Smagghe, Guy; Valterová, Irena; De Meulemeester, Thibaut; Rasmont, Pierre; Michez, Denis

    2017-08-01

    The current bumblebee decline leads to inbreeding in populations that fosters a loss of allelic diversity and diploid male production. As diploid males are viable and their offspring are sterile, bumblebee populations can quickly fall in a vortex of extinction. In this article, we investigate for the first time a potential premating mechanism through a major chemical reproductive trait (male cephalic labial gland secretions) that could prevent monandrous virgin queens from mating with diploid males. We focus our study on the cephalic labial gland secretions of diploid and haploid males of Bombus terrestris (L.). Contrary to initial expectations, our results do not show any significant differentiation of cephalic labial gland secretions between diploid and haploid specimens. Queens seem therefore to be unable to avoid mating with diploid males based on their compositions of cephalic labial gland secretions. This suggests that the vortex of extinction of diploid males could not be stopped through premating avoidance based on the cephalic labial gland secretions but other mechanisms could avoid mating between diploid males and queens. © 2016 Institute of Zoology, Chinese Academy of Sciences.

  4. A study on effective extraction of isoflavones from soy germ using the electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong Hoon [Radiation Research Division for Industry and Environment, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongup-si, 580-185 Jeollabuk-do (Korea, Republic of); Choi, Tae Beom [Radiation Research Division for Industry and Environment, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongup-si, 580-185 Jeollabuk-do (Korea, Republic of); Department of Chemistry, Dongguk University, 3 Pildong, Chunggu, Seoul 100-715 (Korea, Republic of); Kim, Sang Wook [Radiation Research Division for Industry and Environment, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongup-si, 580-185 Jeollabuk-do (Korea, Republic of)], E-mail: swkim@kaeri.re.kr; Hur, Min Goo; Yang, Seung Dae [Radiation Research Division for Industry and Environment, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongup-si, 580-185 Jeollabuk-do (Korea, Republic of); Yu, Kook Hyun [Department of Chemistry, Dongguk University, 3 Pildong, Chunggu, Seoul 100-715 (Korea, Republic of)], E-mail: yukook@dongguk.edu

    2009-07-15

    Soy germ was irradiated with 2 MeV electron beam with different doses ranging from 1 to 20 kGy. The amount of isoflavones from irradiated soy germ was compared with those from natural soy germ by extracting with ethanol and methanol. The changed amounts of isoflavones were measured by high-performance liquid chromatography with standard calibration curve. Each extract of soy germ was quantified for antioxidant activity with 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging method. The amount of isoflavones was found to be increased after electron-beam irradiation. Particularly ethanol extract with 15 kGy irradiated soy germ contained the maximum amount of isoflavones. Antioxidant activity of irradiated soy germ was higher than that of natural soy germ.

  5. Primary Germ Cell Tumor of Testes with Extensive Lymph Nodal and Splenic Metastases Masquerading Lymphoma on 18-F-FDG PET/CT

    Science.gov (United States)

    Tripathy, Sarthak; Mukherjee, Anirban; Bal, Chandrasekhar; Tripathi, Madhavi; Mallick, Saumyaranjan; Shamim, Shamim Ahmed

    2017-01-01

    Germ cell tumors (GCT) account for the 95% of the malignancies associated with testes. They are the most common solid malignancies affecting the males in the age group of 15–35 years. It is known to be bilateral in 3% of cases. We herein present FDG PET-CT findings of a case with biopsy proven GCT with multiple lymph nodal and splenic metastases mimicking lymphomatous neoplasm. PMID:28533651

  6. Construction of a dense genetic linkage map and mapping quantitative trait loci for economic traits of a doubled haploid population of Pyropia haitanensis (Bangiales, Rhodophyta).

    Science.gov (United States)

    Xu, Yan; Huang, Long; Ji, Dehua; Chen, Changsheng; Zheng, Hongkun; Xie, Chaotian

    2015-09-21

    Pyropia haitanensis is one of the most economically important mariculture crops in China. A high-density genetic map has not been published yet and quantitative trait locus (QTL) mapping has not been undertaken for P. haitanensis because of a lack of sufficient molecular markers. Specific length amplified fragment sequencing (SLAF-seq) was developed recently for large-scale, high resolution de novo marker discovery and genotyping. In this study, SLAF-seq was used to obtain mass length polymorphic markers to construct a high-density genetic map for P. haitanensis. In total, 120.33 Gb of data containing 75.21 M pair-end reads was obtained after sequencing. The average coverage for each SLAF marker was 75.50-fold in the male parent, 74.02-fold in the female parent, and 6.14-fold average in each double haploid individual. In total, 188,982 SLAFs were detected, of which 6731 were length polymorphic SLAFs that could be used to construct a genetic map. The final map included 4550 length polymorphic markers that were combined into 740 bins on five linkage groups, with a length of 874.33 cM and an average distance of 1.18 cM between adjacent bins. This map was used for QTL mapping to identify chromosomal regions associated with six economically important traits: frond length, width, thickness, fresh weight, growth rates of frond length and growth rates of fresh weight. Fifteen QTLs were identified for these traits. The value of phenotypic variance explained by an individual QTL ranged from 9.59 to 16.61 %, and the confidence interval of each QTL ranged from 0.97 cM to 16.51 cM. The first high-density genetic linkage map for P. haitanensis was constructed, and fifteen QTLs associated with six economically important traits were identified. The results of this study not only provide a platform for gene and QTL fine mapping, map-based gene isolation, and molecular breeding for P. haitanensis, but will also serve as a reference for positioning sequence scaffolds on a physical

  7. MRI Findings of Suprasellar Germ Cell Tumors in Two Dogs.

    Science.gov (United States)

    Cook, Laurie; Tensley, Michelle; Drost, Wm Tod; Koivisto, Christopher; Oglesbee, Michael

    A 4 yr old border collie presenting for mydriasis and decreased mentation and a 7 yr old Boston terrier presenting for obtundation, head tilt, and paraparesis were both evaluated using MRI. Findings in both included mass lesions of the thalamus and brainstem that were hypo- to isointense on T1-weighted images and hyperintense on T2-weighted images with regions of hypointensity, and robust contrast enhancement and displacement of adjacent structures. Postmortem histopathology findings, tumor location, and a mixed pattern of epithelial cell differentiation were consistent with germ cell tumor in both cases. Germ cell tumor of the suprasellar region is an infrequently reported neoplasm of dogs and imaging findings in this species have not been well described in the prior literature.

  8. Video-assisted thoracic surgery mediastinal germ cell metastasis resection.

    Science.gov (United States)

    Nardini, Marco; Jayakumar, Shruti; Migliore, Marcello; Dunning, Joel

    2017-07-01

    Thoracoscopy can be safely used for dissection of masses in the visceral mediastinum. We report the case of a 31-year-old man affected by metastatic germ cell tumour and successfully treated with a 3-port posterior approach video-assisted thoracic surgery. © The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  9. Radiation-induced genetic effects in germ cells of mammals

    International Nuclear Information System (INIS)

    Van Buul, P.P.W.

    1993-01-01

    The aim of the project is to gain information on the effects of ionizing radiation on germ cells of rodents and primates as measured by induced chromosomal translocations. Different aspects of the very significant interspecies differences between the mouse and the rhesus monkey (Macaca mulatta) for translocation induction in spermatogonial stem cells were studied. In addition, possible mechanisms for the well established reduced transmission of induced mouse translocations were investigated. (R.P.) 6 refs

  10. On the number of founding germ cells in humans

    Directory of Open Access Journals (Sweden)

    Byers Breck

    2005-08-01

    Full Text Available Abstract Background The number of founding germ cells (FGCs in mammals is of fundamental significance to the fidelity of gene transmission between generations, but estimates from various methods vary widely. In this paper we obtain a new estimate for the value in humans by using a mathematical model of germ cell development that depends on available oocyte counts for adult women. Results The germline-development model derives from the assumption that oogonial proliferation in the embryonic stage starts with a founding cells at t = 0 and that the subsequent proliferation can be defined as a simple stochastic birth process. It follows that the population size X(t at the end of germline expansion (around the 5th month of pregnancy in humans; t = 0.42 years is a random variable with a negative binomial distribution. A formula based on the expectation and variance of this random variable yields a moment-based estimate of a that is insensitive to the progressive reduction in oocyte numbers due to their utilization and apoptosis at later stages of life. In addition, we describe an algorithm for computing the maximum likelihood estimation of the FGC population size (a, as well as the rates of oogonial division and loss to apoptosis. Utilizing both of these approaches to evaluate available oocyte-counting data, we have obtained an estimate of a = 2 – 3 for Homo sapiens. Conclusion The estimated number of founding germ cells in humans corresponds well with values previously derived from chimerical or mosaic mouse data. These findings suggest that the large variation in oocyte numbers between individual women is consistent with a smaller founding germ cell population size than has been estimated by cytological analyses.

  11. Rna synthesis of perinatal female and male gametes

    International Nuclear Information System (INIS)

    Doering, R.; Hubaleck, K.

    1980-01-01

    Intensity curves of RNA synthesis in the perinatal phase of gametogenesis were established for rat fetuses and young rats by 3 H-uridine autoradiography. Gonads of male and female rat fetuses were studied on days 15 to 22 p.c. and gonads of young animals on days 1 to 7 p.n. The nuclear surface of the gametes was found to increase continuously. The number of silver grains was the same for male and female gametes up to the 18th day of fetal life, and the same applies to the silver grain density. The rate of RNA synthesis of male germ celles remained at a constant, low level throughout the study; in the female germ cells, a 10-fold increase in RNA synthesis was measured after the 19th day of fetal life. (orig./MG) [de

  12. European consensus on diagnosis and treatment of germ cell cancer: a report of the European Germ Cell Cancer Consensus Group (EGCCCG)

    NARCIS (Netherlands)

    Schmoll, H. J.; Souchon, R.; Krege, S.; Albers, P.; Beyer, J.; Kollmannsberger, C.; Fossa, S. D.; Skakkebaek, N. E.; de Wit, R.; Fizazi, K.; Droz, J. P.; Pizzocaro, G.; Daugaard, G.; de Mulder, P. H. M.; Horwich, A.; Oliver, T.; Huddart, R.; Rosti, G.; Paz Ares, L.; Pont, O.; Hartmann, J. T.; Aass, N.; Algaba, F.; Bamberg, M.; Bodrogi, I.; Bokemeyer, C.; Classen, J.; Clemm, S.; Culine, S.; de Wit, M.; Derigs, H. G.; Dieckmann, K. P.; Flasshove, M.; Garcia del Muro, X.; Gerl, A.; Germa-Lluch, J. R.; Hartmann, M.; Heidenreich, A.; Hoeltl, W.; Joffe, J.; Jones, W.; Kaiser, G.; Klepp, O.; Kliesch, S.; Kisbenedek, L.; Koehrmann, K. U.; Kuczyk, M.; Laguna, M. P.; Leiva, O.; Loy, V.; Mason, M. D.; Mead, G. M.; Mueller, R. P.; Nicolai, N.; Oosterhof, G. O. N.; Pottek, T.; Rick, O.; Schmidberger, H.; Sedlmayer, F.; Siegert, W.; Studer, U.; Tjulandin, S.; von der Maase, H.; Walz, P.; Weinknecht, S.; Weissbach, L.; Winter, E.; Wittekind, C.

    2004-01-01

    Germ cell tumour is the most frequent malignant tumour type in young men with a 100% rise in the incidence every 20 years. Despite this, the high sensitivity of germ cell tumours to platinum-based chemotherapy, together with radiation and surgical measures, leads to the high cure rate of > or = 99%

  13. Biochemical Intestinal Parameters in Germ-free Minipigs and Rats and in Ex-germ-free Minipigs and Rats Monoassociated with Escherichia coli

    Czech Academy of Sciences Publication Activity Database

    Cardona, M.,E.; Kozáková, Hana; Collinder, E.; Persson, A.-K.; Midtvedt, T.; Norin, E.

    2005-01-01

    Roč. 52, - (2005), s. 109-113 ISSN 1548-9213 R&D Projects: GA AV ČR IAA5020101 Institutional research plan: CEZ:AV0Z5020903 Keywords : germ-free * minipigs * ex-germ-free Subject RIV: EE - Microbiology, Virology Impact factor: 2.111, year: 2005

  14. DAZ Family Proteins, Key Players for Germ Cell Development

    Science.gov (United States)

    Fu, Xia-Fei; Cheng, Shun-Feng; Wang, Lin-Qing; Yin, Shen; De Felici, Massimo; Shen, Wei

    2015-01-01

    DAZ family proteins are found almost exclusively in germ cells in distant animal species. Deletion or mutations of their encoding genes usually severely impair either oogenesis or spermatogenesis or both. The family includes Boule (or Boll), Dazl (or Dazla) and DAZ genes. Boule and Dazl are situated on autosomes while DAZ, exclusive of higher primates, is located on the Y chromosome. Deletion of DAZ gene is the most common causes of infertility in humans. These genes, encoding for RNA binding proteins, contain a highly conserved RNA recognition motif and at least one DAZ repeat encoding for a 24 amino acids sequence able to bind other mRNA binding proteins. Basically, Daz family proteins function as adaptors for target mRNA transport and activators of their translation. In some invertebrate species, BOULE protein play a pivotal role in germline specification and a conserved regulatory role in meiosis. Depending on the species, DAZL is expressed in primordial germ cells (PGCs) and/or pre-meiotic and meiotic germ cells of both sexes. Daz is found in fetal gonocytes, spermatogonia and spermatocytes of adult testes. Here we discuss DAZ family genes in a phylogenic perspective, focusing on the common and distinct features of these genes, and their pivotal roles during gametogenesis evolved during evolution. PMID:26327816

  15. Malignant primary germ-cell tumor of the brain

    International Nuclear Information System (INIS)

    Yamamoto, Toyoshiro; Sato, Shinichi; Nakao, Satoshi; Ban, Sadahiko; Namba, Koh

    1983-01-01

    The unusual case of a 15 year old boy with three discrete paraventricular germ-cell tumors is reported.FThe first tumor was located just lateral to the left thalamus and included a massive cystic part around it, the second tumor in the paraventricular region above the head of the left caudate nucleus and the third tumor in the medial part of the left parietal lobe.FTotal removal of all tumors was successfully accomplished in stages at four separate operations, namely, the first tumor was removed through the left transsylvian approach, the second tumor via left superior frontal gyrus and the third tumor via left superior frontal gyrus and left superior parietal lobule.FHistological examination revealed that the first tumor was teratoma, the second was choriocarcinoma and the third was germinoma.FPrimary germ-cell tumors of the brain can be divided into 5 groups: 1) germinoma; 2) embryonal carcinoma; 3) choriocarcinoma; 4) yolk-sac tumor; or 5) teratoma.FIn this case, a combination of three different histological patterns was seen. If malignant germ-cell tumor is supected on CT, aggressive extirpation should be done, not only to determine the exact diagnosis, but also to provide the basis for subsequent adjunctive therapy. (author)

  16. Origins and molecular biology of testicular germ cell tumors.

    Science.gov (United States)

    Reuter, Victor E

    2005-02-01

    Testicular germ cell tumors can be divided into three groups (infantile/prepubertal, adolescent/young adult and spermatocytic seminoma), each with its own constellation of clinical histology, molecular and clinical features. They originate from germ cells at different stages of development. The most common testicular cancers arise in postpubertal men and are characterized genetically by having one or more copies of an isochromosome of the short arm of chromosome 12 [i(12p)] or other forms of 12p amplification and by aneuploidy. The consistent gain of genetic material from chromosome 12 seen in these tumors suggests that it has a crucial role in their development. Intratubular germ cell neoplasia, unclassified type (IGCNU) is the precursor to these invasive tumors. Several factors have been associated with their pathogenesis, including cryptorchidism, elevated estrogens in utero and gonadal dysgenesis. Tumors arising in prepubertal gonads are either teratomas or yolk sac tumors, tend to be diploid and are not associated with i(12p) or with IGCNU. Spermatocytic seminoma (SS) arises in older patients. These benign tumors may be either diploid or aneuploid and have losses of chromosome 9 rather than i(12p). Intratubular SS is commonly encountered but IGCNU is not. The pathogenesis of prepubertal GCT and SS is poorly understood.

  17. POMB/ACE chemotherapy for mediastinal germ cell tumours.

    Science.gov (United States)

    Bower, M; Brock, C; Holden, L; Nelstrop, A; Makey, A R; Rustin, G J; Newlands, E S

    1997-05-01

    Mediastinal germ cell tumours (MGCT) are rare and most published series reflect the experiences of individual institutions over many years. Since 1979, we have treated 16 men (12 non-seminomatous germ cell tumours and 4 seminomas) with newly diagnosed primary MGCT with POMB/ACE chemotherapy and elective surgical resection of residual masses. This approach yielded complete remissions in 15/16 (94%) patients. The median follow-up was 6.0 years and no relapses occurred more than 2 years after treatment. The 5 year overall survival in the non-seminomatous germ cell tumours (NSGCT) is 73% (95% confidence interval 43-90%). One patient with NSGCT developed drug-resistant disease and died without achieving remission and 2 patients died of relapsed disease. In addition, 4 patients with bulky and/or metastatic seminoma were treated with POMB/ACE. One died of treatment-related neutropenic sepsis in complete remission and one died of relapsed disease. Finally, 4 patients (2 NSGCT and 2 seminomas) referred at relapse were treated with POMB/ACE and one was successfully salvaged. The combination of POMB/ACE chemotherapy and surgery is effective management for MGCT producing high long-term survival rates.

  18. Tre1, a G protein-coupled receptor, directs transepithelial migration of Drosophila germ cells.

    Directory of Open Access Journals (Sweden)

    Prabhat S Kunwar

    2003-12-01

    Full Text Available In most organisms, germ cells are formed distant from the somatic part of the gonad and thus have to migrate along and through a variety of tissues to reach the gonad. Transepithelial migration through the posterior midgut (PMG is the first active step during Drosophila germ cell migration. Here we report the identification of a novel G protein-coupled receptor (GPCR, Tre1, that is essential for this migration step. Maternal tre1 RNA is localized to germ cells, and tre1 is required cell autonomously in germ cells. In tre1 mutant embryos, most germ cells do not exit the PMG. The few germ cells that do leave the midgut early migrate normally to the gonad, suggesting that this gene is specifically required for transepithelial migration and that mutant germ cells are still able to recognize other guidance cues. Additionally, inhibiting small Rho GTPases in germ cells affects transepithelial migration, suggesting that Tre1 signals through Rho1. We propose that Tre1 acts in a manner similar to chemokine receptors required during transepithelial migration of leukocytes, implying an evolutionarily conserved mechanism of transepithelial migration. Recently, the chemokine receptor CXCR4 was shown to direct migration in vertebrate germ cells. Thus, germ cells may more generally use GPCR signaling to navigate the embryo toward their target.

  19. Germ cell development in the Honeybee (Apis mellifera; Vasa and Nanos expression

    Directory of Open Access Journals (Sweden)

    Dearden Peter K

    2006-02-01

    Full Text Available Abstract Background Studies of specification of germ-cells in insect embryos has indicated that in many taxa the germ cells form early in development, and their formation is associated with pole plasm, germ plasm or an organelle called the oosome. None of these morphological features associated with germ cell formation have been identified in the Honeybee Apis mellifera. In this study I report the cloning and expression analysis of Honeybee homologues of vasa and nanos, germ cell markers in insects and other animals. Results Apis vasa and nanos RNAs are present in early honeybee embryos, but the RNAs clear rapidly, without any cells expressing these germ cell markers past stage 2. These genes are then only expressed in a line of cells in the abdomen from stage 9 onwards. These cells are the developing germ cells that are moved dorsally by dorsal closure and are placed in the genital ridge. Conclusion This study of the expression of germ cell markers in the honeybee implies that in this species either germ cells are formed by an inductive event, late in embryogenesis, or they are formed early in development in the absence of vasa and nanos expression. This contrasts with germ cell development in other members of the Hymenoptera, Diptera and Lepidoptera.

  20. The diversity of nanos expression in echinoderm embryos supports different mechanisms in germ cell specification.

    Science.gov (United States)

    Fresques, Tara; Swartz, Steven Zachary; Juliano, Celina; Morino, Yoshiaki; Kikuchi, Mani; Akasaka, Koji; Wada, Hiroshi; Yajima, Mamiko; Wessel, Gary M

    2016-07-01

    Specification of the germ cell lineage is required for sexual reproduction in all animals. However, the timing and mechanisms of germ cell specification is remarkably diverse in animal development. Echinoderms, such as sea urchins and sea stars, are excellent model systems to study the molecular and cellular mechanisms that contribute to germ cell specification. In several echinoderm embryos tested, the germ cell factor Vasa accumulates broadly during early development and is restricted after gastrulation to cells that contribute to the germ cell lineage. In the sea urchin, however, the germ cell factor Vasa is restricted to a specific lineage by the 32-cell stage. We therefore hypothesized that the germ cell specification program in the sea urchin/Euechinoid lineage has evolved to an earlier developmental time point. To test this hypothesis we determined the expression pattern of a second germ cell factor, Nanos, in four out of five extant echinoderm clades. Here we find that Nanos mRNA does not accumulate until the blastula stage or later during the development of all other echinoderm embryos except those that belong to the Echinoid lineage. Instead, Nanos is expressed in a restricted domain at the 32-128 cell stage in Echinoid embryos. Our results support the model that the germ cell specification program underwent a heterochronic shift in the Echinoid lineage. A comparison of Echinoid and non-Echinoid germ cell specification mechanisms will contribute to our understanding of how these mechanisms have changed during animal evolution. © 2016 Wiley Periodicals, Inc.

  1. Effects of environmental Bisphenol A exposures on germ cell development and Leydig cell function in the human fetal testis.

    Directory of Open Access Journals (Sweden)

    Soria Eladak

    Full Text Available Using an organotypic culture system termed human Fetal Testis Assay (hFeTA we previously showed that 0.01 μM BPA decreases basal, but not LH-stimulated, testosterone secreted by the first trimester human fetal testis. The present study was conducted to determine the potential for a long-term antiandrogenic effect of BPA using a xenograft model, and also to study the effect of BPA on germ cell development using both the hFETA and xenograft models.Using the hFeTA system, first trimester testes were cultured for 3 days with 0.01 to 10 μM BPA. For xenografts, adult castrate male nude mice were injected with hCG and grafted with first trimester testes. Host mice received 10 μM BPA (~ 500 μg/kg/day in their drinking water for 5 weeks. Plasma levels of total and unconjugated BPA were 0.10 μM and 0.038 μM respectively. Mice grafted with second trimester testes received 0.5 and 50 μg/kg/day BPA by oral gavage for 5 weeks.With first trimester human testes, using the hFeTA model, 10 μM BPA increased germ cell apoptosis. In xenografts, germ cell density was also reduced by BPA exposure. Importantly, BPA exposure significantly decreased the percentage of germ cells expressing the pluripotency marker AP-2γ, whilst the percentage of those expressing the pre-spermatogonial marker MAGE-A4 significantly increased. BPA exposure did not affect hCG-stimulated androgen production in first and second trimester xenografts as evaluated by both plasma testosterone level and seminal vesicle weight in host mice.Exposure to BPA at environmentally relevant concentrations impairs germ cell development in first trimester human fetal testis, whilst gonadotrophin-stimulated testosterone production was unaffected in both first and second trimester testis. Studies using first trimester human fetal testis demonstrate the complementarity of the FeTA and xenograft models for determining the respective short-term and long term effects of environmental exposures.

  2. The clinical impact of {sup 18}F-FDG PET/CT in extracranial pediatric germ cell tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hart, Adam; Vali, Reza; Marie, Eman; Shammas, Amer [The Hospital for Sick Children and University of Toronto, Department of Medical Imaging, Nuclear Medicine, Toronto, ON (Canada); Shaikh, Furqan [The Hospital for Sick Children and University of Toronto, Division of Haematology and oncology, Toronto, ON (Canada)

    2017-10-15

    Extracranial germ cell tumors are an uncommon pediatric malignancy with limited information on the clinical impact of {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the literature. The purpose of this study was to evaluate and compare the clinical impact on management of {sup 18}F-FDG PET/CT with diagnostic computed tomography (CT) in pediatric extracranial germ cell tumor. The list of {sup 18}F-FDG PET/CT performed for extracranial germ cell tumor between May 2007 and November 2015 was obtained from the nuclear medicine database. {sup 18}F-FDG PET/CT and concurrent diagnostic CT were obtained and independently reviewed. Additionally, the patients' charts were reviewed for duration of follow-up and biopsy when available. The impact of {sup 18}F-FDG PET/CT compared with diagnostic CT on staging and patient management was demonstrated by chart review, imaging findings and follow-up studies. During the study period, 9 children (5 males and 4 females; age range: 1.6-17 years, mode age: 14 years) had 11 {sup 18}F-FDG PET/CT studies for the evaluation of germ cell tumor. Diagnostic CTs were available for comparison in 8 patients (10 {sup 18}F-FDG PET/CT studies). The average interval between diagnostic CT and PET/CT was 7.2 days (range: 0-37 days). In total, five lesions concerning for active malignancy were identified on diagnostic CT while seven were identified on PET/CT. Overall, {sup 18}F-FDG PET/CT resulted in a change in management in 3 of the 9 patients (33%). {sup 18}F-FDG PET/CT had a significant impact on the management of pediatric germ cell tumors in this retrospective study. Continued multicenter studies are required secondary to the rarity of this tumor to demonstrate the benefit of {sup 18}F-FDG PET/CT in particular clinical scenarios. (orig.)

  3. FLI-1 Flightless-1 and LET-60 Ras control germ line morphogenesis in C. elegans

    Directory of Open Access Journals (Sweden)

    Dentler William L

    2008-05-01

    Full Text Available Abstract Background In the C. elegans germ line, syncytial germ line nuclei are arranged at the cortex of the germ line as they exit mitosis and enter meiosis, forming a nucleus-free core of germ line cytoplasm called the rachis. Molecular mechanisms of rachis formation and germ line organization are not well understood. Results Mutations in the fli-1 gene disrupt rachis organization without affecting meiotic differentiation, a phenotype in C. elegans referred to here as the germ line morphogenesis (Glm phenotype. In fli-1 mutants, chains of meiotic germ nuclei spanned the rachis and were partially enveloped by invaginations of germ line plasma membrane, similar to nuclei at the cortex. Extensions of the somatic sheath cells that surround the germ line protruded deep inside the rachis and were associated with displaced nuclei in fli-1 mutants. fli-1 encodes a molecule with leucine-rich repeats and gelsolin repeats similar to Drosophila flightless 1 and human Fliih, which have been shown to act as cytoplasmic actin regulators as well as nuclear transcriptional regulators. Mutations in let-60 Ras, previously implicated in germ line development, were found to cause the Glm phenotype. Constitutively-active LET-60 partially rescued the fli-1 Glm phenotype, suggesting that LET-60 Ras and FLI-1 might act together to control germ line morphogenesis. Conclusion FLI-1 controls germ line morphogenesis and rachis organization, a process about which little is known at the molecular level. The LET-60 Ras GTPase might act with FLI-1 to control germ line morphogenesis.

  4. Transgenerational effect of the endocrine disruptor vinclozolin on male spermatogenesis.

    Science.gov (United States)

    Anway, Matthew D; Memon, Mushtaq A; Uzumcu, Mehmet; Skinner, Michael K

    2006-01-01

    The current study was designed to examine the actions of a model endocrine disruptor on embryonic testis development and male fertility. Pregnant rats (F0) that received a transient embryonic exposure to an environmental endocrine disruptor, vinclozolin, had male offspring (F1) with reduced spermatogenic capacity. The reduced spermatogenetic capacity observed in the F1 male offspring was transmitted to the subsequent generations (F2-F4). The administration of vinclozolin, an androgen receptor antagonist, at 100 mg/kg/day from embryonic day 8-14 (E8-E14) of pregnancy to only the F0 dam resulted in a transgenerational phenotype in the subsequent male offspring in the F1-F4 generations. The litter size and male/female sex ratios were similar in controls and the vinclozolin generations. The average testes/body weight index of the postnatal day 60 (P60) males was not significantly different in the vinclozolin-treated generations compared to the controls. However, the testicular spermatid number, as well as the epididymal sperm number and motility, were significantly reduced in the vinclozolin generations compared to the control animals. Postnatal day 20 (P20) testis from the vinclozolin F2 generation had no morphological abnormalities, but did have an increase in spermatogenic cell apoptosis. Although the P60 testis morphology was predominantly normal, the germ cell apoptosis was significantly increased in the testes cross sections of animals from the vinclozolin generations. The increase in apoptosis was stage-specific in the testis, with tubules at stages IX-XIV having the highest increase in apoptotic germ cells. The tubules at stages I-V also had an increase in apoptotic germ cells compared to the control samples, but tubules at stages VI-VIII had no increase in apoptotic germ cells. An outcross of a vinclozolin generation male with a wild-type female demonstrated that the reduced spermatogenic cell phenotype was transmitted through the male germ line. An outcross

  5. Endogenous antispermatogenic agents: prospects for male contraception.

    Science.gov (United States)

    Ewing, L L; Robaire, B

    1978-01-01

    A review of endogenous antispermatogenic agents as prospects for male contraception is reported. It is demonstrated that endogenous compounds exert regulatory influences at 4 major levels in the male: 1) between germ cells; 2) between Sertoli and germ cells; 3) between Leydig cells and seminiferous tubules; and 4) between the central nervous system and the testis. Efforts to interrupt spermatogenesis have failed to find application as male contraceptives for various reasons: 1) some investigators ignored the vulnerable control points by utilizing nonspecific agents; 2) others attacked a vulnerable control point but used synthetic drugs that had deleterious side effects; and 3) still others attacked a vulnerable control point with a relatively innocuous drug but used an impractical mode of drug administration. The potential for devising innovative techniques for administering relatively innocuous drugs at dosages sufficient to produce sterility without causing deleterious side effects is demonstrated. The most promising solution for the development of an antispermatogenic male contraceptive is the interference with the adenohypophyseal-gonadal axis via the subcutaneous sustained release of steroid formulations containing either androgen-danazol, androgen-progestin, or androgen-estrogen formulations. Another promising agent would be luteinizing releasing hormone agonist-androgen formulation.

  6. Study of variation of tocochromanol and phytosterol contents in black and yellow seeds of Brassica napus L. doubled haploid populations.

    Science.gov (United States)

    Cegielska-Taras, Teresa; Nogala-Kałucka, Małgorzata; Szala, Laurencja; Siger, Aleksander

    2016-01-01

    In the study, an analysis of tocopherols, plastochomanol-8 and phytosterols was conducted using DH lines obtained from F1 hybrids of reciprocal crosses between yellow- and black-seeded lines. The biological material for the study consisted of two DH populations of winter oilseed rape obtained from F1 hybrids of reciprocal crosses between two DH lines: yellow- and black-seeded. Seed color was determined using a ColorFlex spectrophotometer. Fat content was determined via pulsed NMR. The levels of tocopherols, and plastochromanol-8 are analyzed using HPLC. Phytosterol contents and composition were determined by the GC method. The fat content of the black-seeded parental line was 49% and this was higher than that of the yellow-seeded parental line (44%). The fat content of DH line populations ranged from 44 to 51%. Total tocopherol content ranged from 460 to 602 mg/kg and the α-T/γ-T ratio was from 0.66 to 1.09. In parental lines H2-26 and Z-114 the total tocopherol content was 534 and 525 mg/kg, but the α-T/γ-T ratios were 0.81 and 1.21, respectively. The yellow-seeded parental line (Z-114) was characterized by a higher PC-8 content (81 mg/kg) than the H2-26 black-seeded parental line (58 mg/kg). The largest part of the total phytosterol content in seeds of both populations was β-sitosterol from 976 to 2148 mg/kg, followed by campasterol, from 636 to 1364 mg/kg, and brassicasterol from 375 to 678 mg/kg. The total tocopherol content ranged from 462 to 595 mg/kg (population HxZ) and from 460 to 602 mg/kg (population ZxH). Significantly positive correlations were observed between the seed color with α-T (r = 0.38, p phytosterol content were not noted. Considering the range of genetic variation among doubled haploids of two populations, selected DH lines may be good parents for further breeding programs focused on increasing the amount and improving the quality of oilseed rapeseed oil. However, further studies will also be made to determine the influence of the

  7. Mouse Tafazzin Is Required for Male Germ Cell Meiosis and Spermatogenesis

    NARCIS (Netherlands)

    Cadalbert, Laurence C.; Ghaffar, Farah Naz; Stevenson, David; Bryson, Sheila; Vaz, Frédéric M.; Gottlieb, Eyal; Strathdee, Douglas

    2015-01-01

    Barth syndrome is an X-linked mitochondrial disease, symptoms of which include neutropenia and cardiac myopathy. These symptoms are the most significant clinical consequences of a disease, which is increasingly recognised to have a variable presentation. Mutation in the Taz gene in Xq28 is thought

  8. Retrovirus-mediated in vitro gene transfer into chicken male germ line cells

    Czech Academy of Sciences Publication Activity Database

    Kalina, J.; Šenigl, Filip; Mičáková, A.; Mucksová, J.; Blažková, Jana; Haifeng, Y.; Poplštejn, M.; Hejnar, Jiří; Trefil, P.

    2007-01-01

    Roč. 134, č. 3 (2007), s. 445-453 ISSN 1470-1626 R&D Projects: GA ČR GA523/04/0569 Grant - others:GA MŠk(CZ) 1P05ME722 Institutional research plan: CEZ:AV0Z50520514 Keywords : Transgenic spermatozoa * infection of testicular cells with retrovirus * transgenesis in chicken Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.962, year: 2007

  9. Role for c-Abl and p73 in the radiation response of male germ cells

    NARCIS (Netherlands)

    Hamer, G.; Gademan, I. S.; Kal, H. B.; de rooij, D. G.

    2001-01-01

    p53 plays a central role in the induction of apoptosis of spermatogonia in response to ionizing radiation. In p53(-/-) testes, however, spermatogonial apoptosis still can be induced by ionizing radiation, so p53 independent apoptotic pathways must exist in spermatogonia. Here we show that the p53

  10. Effects of ionizing radiation on male germ cells of crab-eating monkey

    International Nuclear Information System (INIS)

    Okamoto, Masanori; Kitazuma, Masayuki; Tobari, Izuo

    1989-01-01

    Effects of ionizing radiation on sperm concentration, testicular volume, and sperm shape of the crab-eating monkey were studied by using acute and low dose-rate gamma-ray and X-ray. The animals were acutely irradiated with 0.25-3.00 Gy with Cs-137 gamma-ray at a dose-rate of 0.25 Gy/min. Sperm concentrations were decreased with time after irradiation in a dose-dependent fashion. The time required for the lowest concentration of sperm depended on radiation doses. A linear dose-response relationship was seen for sperm concentrations. In comparing the present results in monkeys to previous results in mice and golden hamsters, the sensitivity of spermatogenic cells in killing effect of gamma ray varied in the following order: monkeys>hamsters>mice. The present monkeys were also subjected to whole-body irradiation with 0.3-1.5 Gy of Cs-137 gamma-ray at 1.8 x 10 -5 Gy/min, for the purpose of estimating low-dose rate irradiation on sperm concentrations, testicular volume and sperm shape. Noticeable changes in either sperm concentration or testicular volume did not occur by irradiation of 0.3 Gy. Sperm concentrations were markedly changed with 1.0 Gy. Changes in sperm concentrations and testicular volume after X-ray irradiation at the dose-rate of 0.32 Gy/min showed that killing effects of X-ray are apparently higher than those of gamma-ray. When the incidence of abnormal head shapes of sperm was examined in monkeys with chronic gamma-ray irradiation, the highest incidence of abnormality was 1.5-1.8% at 0.25-0.50 Gy. The incidence of sperm abnormality in monkeys was comparable to that in hamsters; however, it was markedly higher in mice than monkeys. (Namekawa, K)

  11. Assessment of the degree of contamination of rat germ cell preparations using specific cDNA probes

    Directory of Open Access Journals (Sweden)

    Savaris R.F.

    1997-01-01

    Full Text Available Recent reports showing a decrease in sperm count in men have brought new concerns about male infertility. Animal models have been widely used to provide some relevant information about the human male gamete, and extrapolations are made to men and to the clinical context. The present study assesses one of the methods used for separation of germ cells of the adult rat testis, namely centrifugal elutriation followed by density gradients (Percoll®. This method was chosen since it presents the best results for cell purity in separating germ cells from the rat testis. A comparison between continuous and discontinuous Percoll® gradients was performed in order to identify the best type of gradient to separate the cells. Maximal cell purity was obtained for spermatocytes (81 ± 8.2%, mean ± SEM and spermatids (84 ± 2.6% using centrifugal elutriation followed by continuous Percoll® gradients. A significant difference in purity was observed between elongating spermatids harvested from continuous Percoll® gradients and from discontinuous gradients. Molecular analysis was used to assess cell contamination by employing specific probes, namely transition protein 2 (TP2, mitochondrial cytochrome C oxidase II (COX II, and sulfated glycoprotein 1 (SGP1. Molecular analysis of the samples demonstrated that morphological criteria are efficient in characterizing the main composition of the cell suspension, but are not reliable for identifying minimal contamination from other cells. Reliable cell purity data should be established using molecular analysis

  12. Inter Simple Sequence Repeat DNA (ISSR) Polymorphism Utility in Haploid Nicotiana Alata Irradiated Plants for Finding Markers Associated with Gamma Irradiation and Salinity

    International Nuclear Information System (INIS)

    El-Fiki, A.; Adly, M.; El-Metabteb, G.

    2017-01-01

    Nicotiana alata is an ornamental plant. It is a member of family Solanasea. Tobacco (Nicotiana spp.) is one of the most important commercial crops in the world. Wild Nicotiana species, as a store house of genes for several diseases and pests, in addition to genes for several important phytochemicals and quality traits which are not present in cultivated varieties. Inter simple sequence repeat DNA (ISSR) analysis was used to determine the degree of genetic variation in treated haploid Nicotiana alata plants. Total genomic DNAs from different treated haploid plant lets were amplified using five specific primers. All primers were polymorphic. A total of 209 bands were amplified of which 135 (59.47%) polymorphic across the radiation treatments. Whilst, the level of polymorphism among the salinity treatments were 181 (85.6 %). Whereas, the polymorphism among the combined effects between gamma radiation doses and salinity concentrations were 283 ( 73.95% ). Treatments relationships were estimated through cluster analysis (UPGMA) based on ISSR data

  13. Segregation distortion causes large-scale differences between male and female genomes in hybrid ants.

    Science.gov (United States)

    Kulmuni, Jonna; Seifert, Bernhard; Pamilo, Pekka

    2010-04-20

    Hybridization in isolated populations can lead either to hybrid breakdown and extinction or in some cases to speciation. The basis of hybrid breakdown lies in genetic incompatibilities between diverged genomes. In social Hymenoptera, the consequences of hybridization can differ from those in other animals because of haplodiploidy and sociality. Selection pressures differ between sexes because males are haploid and females are diploid. Furthermore, sociality and group living may allow survival of hybrid genotypes. We show that hybridization in Formica ants has resulted in a stable situation in which the males form two highly divergent gene pools whereas all the females are hybrids. This causes an exceptional situation with large-scale differences between male and female genomes. The genotype differences indicate strong transmission ratio distortion depending on offspring sex, whereby the mother transmits some alleles exclusively to her daughters and other alleles exclusively to her sons. The genetic differences between the sexes and the apparent lack of multilocus hybrid genotypes in males can be explained by recessive incompatibilities which cause the elimination of hybrid males because of their haploid genome. Alternatively, differentiation between sexes could be created by prezygotic segregation into male-forming and female-forming gametes in diploid females. Differentiation between sexes is stable and maintained throughout generations. The present study shows a unique outcome of hybridization and demonstrates that hybridization has the potential of generating evolutionary novelties in animals.

  14. Aromatase and estrogen receptors in male reproduction.

    Science.gov (United States)

    Carreau, Serge; Delalande, Christelle; Silandre, Dorothée; Bourguiba, Sonia; Lambard, Sophie

    2006-02-26

    Aromatase is a terminal enzyme which transforms irreversibly androgens into estrogens and it is present in the endoplasmic reticulum of numerous tissues. We have demonstrated that mature rat germ cells express a functional aromatase with a production of estrogens equivalent to that of Leydig cells. In humans in addition to Leydig cells, we have shown the presence of aromatase in ejaculated spermatozoa and in immature germ cells. In most tissues, high affinity estrogen receptors, ERalpha and/or ERbeta, mediate the role of estrogens. Indeed, in human spermatozoa, we have successfully amplified ERbeta mRNA but the protein was not detectable. Using ERalpha antibody we have detected two proteins in human immature germ cells: one at the expected size 66 kDa and another at 46 kDa likely corresponding to the ERalpha isoform lacking exon 1. In spermatozoa only the 46 kDa isoform was present, and we suggest that it may be located on the membrane. In addition, in men genetically deficient in aromatase, it is reported that alterations of spermatogenesis occur both in terms of the number and motility of spermatozoa. All together, these observations suggest that endogenous estrogens are important in male reproduction.

  15. In vitro haploid zygotic embryogenesis due to pollination with maize pollen and induced in vitro androgenesis in Czech wheat breeding genotypes

    Czech Academy of Sciences Publication Activity Database

    Vagera, Jiří; Nesvadba, Z.; Martinek, P.; Ohnoutková, Ludmila

    2001-01-01

    Roč. 47, č. 5 (2001), s. 193-200 ISSN 0370-663X R&D Projects: GA ČR GA521/01/1383; GA ČR GV521/96/K117 Institutional research plan: CEZ:AV0Z5038910 Keywords : haploid zygote * embryogenesis * maize pollen Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.237, year: 2001

  16. Expression Patterns of ERF Genes Underlying Abiotic Stresses in Di-Haploid Populus simonii × P. nigra

    Directory of Open Access Journals (Sweden)

    Shengji Wang

    2014-01-01

    Full Text Available 176 ERF genes from Populus were identified by bioinformatics analysis, 13 of these in di-haploid Populus simonii × P. nigra were investigate by real-time RT-PCR, the results demonstrated that 13 ERF genes were highly responsive to salt stress, drought stress and ABA treatment, and all were expressed in root, stem, and leaf tissues, whereas their expression levels were markedly different in the various tissues. In roots, PthERF99, 110, 119, and 168 were primarily downregulated under drought and ABA treatment but were specifically upregulated under high salt condition. Interestingly, in poplar stems, all ERF genes showed the similar trends in expression in response to NaCl stress, drought stress, and ABA treatment, indicating that they may not play either specific or unique roles in stems in abiotic stress responses. In poplar leaves, PthERF168 was highly induced by ABA treatment, but was suppressed by high salinity and drought stresses, implying that PthERF168 participated in the ABA signaling pathway. The results of this study indicated that ERF genes could play essential but distinct roles in various plant tissues in response to different environment cues and hormonal treatment.

  17. Evaluation of GRCh38 and de novo haploid genome assemblies demonstrates the enduring quality of the reference assembly.

    Science.gov (United States)

    Schneider, Valerie A; Graves-Lindsay, Tina; Howe, Kerstin; Bouk, Nathan; Chen, Hsiu-Chuan; Kitts, Paul A; Murphy, Terence D; Pruitt, Kim D; Thibaud-Nissen, Françoise; Albracht, Derek; Fulton, Robert S; Kremitzki, Milinn; Magrini, Vincent; Markovic, Chris; McGrath, Sean; Steinberg, Karyn Meltz; Auger, Kate; Chow, William; Collins, Joanna; Harden, Glenn; Hubbard, Timothy; Pelan, Sarah; Simpson, Jared T; Threadgold, Glen; Torrance, James; Wood, Jonathan M; Clarke, Laura; Koren, Sergey; Boitano, Matthew; Peluso, Paul; Li, Heng; Chin, Chen-Shan; Phillippy, Adam M; Durbin, Richard; Wilson, Richard K; Flicek, Paul; Eichler, Evan E; Church, Deanna M

    2017-05-01

    The human reference genome assembly plays a central role in nearly all aspects of today's basic and clinical research. GRCh38 is the first coordinate-changing assembly update since 2009; it reflects the resolution of roughly 1000 issues and encompasses modifications ranging from thousands of single base changes to megabase-scale path reorganizations, gap closures, and localization of previously orphaned sequences. We developed a new approach to sequence generation for targeted base updates and used data from new genome mapping technologies and single haplotype resources to identify and resolve larger assembly issues. For the first time, the reference assembly contains sequence-based representations for the centromeres. We also expanded the number of alternate loci to create a reference that provides a more robust representation of human population variation. We demonstrate that the updates render the reference an improved annotation substrate, alter read alignments in unchanged regions, and impact variant interpretation at clinically relevant loci. We additionally evaluated a collection of new de novo long-read haploid assemblies and conclude that although the new assemblies compare favorably to the reference with respect to continuity, error rate, and gene completeness, the reference still provides the best representation for complex genomic regions and coding sequences. We assert that the collected updates in GRCh38 make the newer assembly a more robust substrate for comprehensive analyses that will promote our understanding of human biology and advance our efforts to improve health. © 2017 Schneider et al.; Published by Cold Spring Harbor Laboratory Press.

  18. Global gene transcription patterns in in vitro-cultured fertilized embryos and diploid and haploid murine parthenotes

    International Nuclear Information System (INIS)

    Cui Xiangshun; Li Xingyu; Kim, Nam-Hyung

    2007-01-01

    To gain insights into the roles the paternal genome and chromosome number play in pre-implantation development, we cultured fertilized embryos and diploid and haploid parthenotes (DPs and HPs, respectively), and compared their development and gene expression patterns. The DPs and fertilized embryos did not differ in developmental ability but HPs development was slower and characterized by impaired compaction and blastocoel formation. Microarray analysis revealed that fertilized blastocysts expressed several genes at higher levels than DP blastocysts; these included the Y-chromosome-specific gene eukaryotic translation initiation factor 2, subunit 3, structural gene Y-linked (Eif2s3y) and the imprinting gene U2 small nuclear ribonucleoprotein auxiliary factor 1, related sequence 1 (U2af1-rs1). We also found that when DPs and HPs were both harvested at 44 and 58 h of culture, they differed in the expression of 38 and 665 genes, respectively. However, when DPs and HPs were harvested at the midpoints of 4-cell stage (44 and 49 h, respectively), no differences in expression was observed. Similarly, when the DPs and HPs were harvested when they became blastocysts (102 and 138 h, respectively), only 15 genes showed disparate expression. These results suggest that while transcripts needed for early development are delayed in HPs, it does progress sufficiently for the generation of the various developmental stages despite the lack of genetic components

  19. Response of Barley Double Haploid Lines to the Grain Yield and Morphological Traits under Water Deficit Stress Conditions

    Directory of Open Access Journals (Sweden)

    Maroof Khalily

    2017-04-01

    Full Text Available To study the relationships of grain yield and some of agro-morphological traits in 40 doubled haploid (DH lines along with parental and three check genotypes in a randomized complete block design with two replications under two water regimes (normal and stress were evaluated during 2011-2012 and 2012-2013 growing seasons. Combined analysis of variance showed significant difference for all the traits in terms of the year, water regimes, lines, and and line × year. Comparison of group means, between non-stress and stress conditions, showed that DH lines had the lowest reduction percentage for the number of grains per spike, thousand grain weight, grain yield and biological yield as opposed to check genotypes. The correlation between grain yield with biological yield, harvest index, thousand grain weight, and hectoliter of kernel weight in both conditions, were highly significant and positive. Based on stepwise regression the peduncle length, number of seeds per spike, thousand seed weight, and hectoliter of kernel weight had important effect on increasing seed yield. The result of path analysis showed that these traits had the highest direct effect on grain yield. Based on mean comparisons of morphological characters as well as STI and GMP indices it can be concluded that lines No.11, 13, 14, 24, 29, 30, 35 and 39 were distinguished to be desirable lines for grain yield and their related traits and also tolerant lines in terms of response to drought stress conditions.

  20. Immature germ cells in semen - correlation with total sperm count and sperm motility

    Directory of Open Access Journals (Sweden)

    Priya S Patil

    2013-01-01

    Conclusions: Round cells in semen can be differentiated into immature germ cells and leucocytes using simple staining methods. The differential counts mentioned in a semen report give valuable and clinically relevant information. In this study, we observed a negative correlation between total count and immature germ cells, as well as sperm motility and shedding of immature germ cells. The latter was statistically significant with a P value 0.000.

  1. Fatty acid composition of maize germ oil from high-oil hybrids wet-milling processing

    Directory of Open Access Journals (Sweden)

    Jovanović Petar Lj.

    2005-01-01

    Full Text Available Maize germ was obtained by wet-milling laboratory processing of domestic high-oil maize hybrids. After separation, the germ was subjected to extraction of maize oil. Fatty acid composition of maize germ oil was determined by gas chromatography. The results showed very high levels of unsaturated fatty acids and a constant sum of oleic and linoleic acids in oils of different maize hybrids.

  2. Male Infertility

    Science.gov (United States)

    ... hypothalamus, pituitary, thyroid and adrenal glands. Low testosterone (male hypogonadism) and other hormonal problems have a number of possible underlying causes. Defects of tubules that transport sperm. Many ... syndrome — in which a male is born with two X chromosomes and one ...

  3. Production of haploid plants from ten hybrids of bread wheat (Triticum aestivum L. through wide hybridization with maize (Zea mays L. Producción de plantas haploides a partir de 10 híbridos de trigo para pan (Triticum aestivum L. mediante hibridación interespecífica con maíz (Zea mays L.

    Directory of Open Access Journals (Sweden)

    L.E. Torres

    2010-12-01

    Full Text Available The aim of this work was to obtain haploid plants of bread wheat through wide hybridization with maize. The experimental material included ten bread wheat hybrids (female parent and one population of maize (pollen donor. Two assays were carried out in two different seasons (summer and winter. Wheat spikes were manually emasculated, each spike was pollinated twice with fresh pollen of maize and a solution of 2,4-D (100 mg l-1 was sprayed on pollinated florets and injected in the upper internode. Fifteen and 21 days after pollination caryopses were removed and surface sterilized. Embryos were cultured in tubes containing B5 medium. The ten hybrid combinations produced caryopses, but only eight of these hybrids produced embryos and, in six of them, the recovered embryos developed into haploid plantlets. The results showed that there is genotypic influence of the wheat parents on the percentage of haploid embryo formation, in accordance with the results obtained by other authors. Regardless of the genotype, the sowing season and the harvest date, 69.4% of the pollinated flowers gave place to the formation of caryopses, 5.5% of these caryopses developed into presumably haploid embryos (for their morphological phenotypes and 26.1 % of the recovered embryos developed into haploid plantlets.El objetivo del presente trabajo fue obtener plantas haploides de trigo para pan mediante hibridación interespecífica con maíz. Se utilizaron 10 híbridos de trigo para pan (madre y una población de maíz (donante de polen; se llevaron a cabo dos ensayos en distintas estaciones de cultivo. Cada espiga de trigo fue emasculada manualmente y polinizada dos veces con polen fresco de maíz; las flores polinizadas se pulverizaron con una solución de 2,4-D (100 mg l-1, la que también se inyectó en la base de la espiga. Las semillas se cosecharon a los 15 y 21 días posteriores a la polinización. Los embriones recuperados se colocaron en tubos conteniendo medio de

  4. Origin of pluripotent germ cell tumours: the role of microenvironment during embryonic development

    DEFF Research Database (Denmark)

    Kristensen, David Møbjerg; Sonne, Si Brask; Ottesen, Anne Marie

    2008-01-01

    into virtually any type of tissue and form teratomas (non-seminomas). CIS cells display a close phenotypic similarity to fetal germ cells (primordial germ cells or gonocytes) suggesting an origin due to a developmental delay or arrest of differentiation of early germ cells. The pluripotency of these neoplasms...... in several tissue specific stem cells, such as TFAP2C (AP-2gamma) or KIT. CIS and seminomas highly express a number of pre-meiotic germ cell specific genes, which are down-regulated during development to non-seminomas, while the expression of other embryonic markers, such as SOX2, is up...

  5. Pathogenesis of germ cell neoplasia in testicular dysgenesis and disorders of sex development

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Lindhardt Johansen, Marie; Juul, Anders

    2015-01-01

    in individuals with 46,XY DSD. We summarise knowledge concerning development and sex differentiation of human gonads, with focus on sex-dimorphic steps of germ cell maturation, including meiosis. We also briefly outline the histopathology of germ cell neoplasia in situ (GCNIS) and gonadoblastoma (GDB), which......Development of human gonads is a sex-dimorphic process which evolved to produce sex-specific types of germ cells. The process of gonadal sex differentiation is directed by the action of the somatic cells and ultimately results in germ cells differentiating to become functional gametes through...

  6. Isolation and purification of wheat germ agglutinin and analysis of its properties

    Science.gov (United States)

    Wang, Han

    2017-12-01

    In this paper, the wheat germ agglutinin was isolated and purified by affinity chromatography of chicken ovomucoid as ligand. The physicochemical properties were analyzed. The chicken ovomucoid was isolated from egg white and conjugated to affinity chromatography column agarose gel to prepare affinity adsorbent. The crude extract of wheat germ was freezedried by affinity chromatography. The physicochemical properties were analyzed by SDSpolyacrylamide gel electrophoresis and isoelectric focusing electrophoresis. And the relative molecular mass and isoelectric point of wheat germ agglutinin were obtained, and the high efficiency of purification of wheat germ agglutinin was proved by affinity chromatography.

  7. Peculiarities in the CT findings of germ cell tumors in various tumor localizations

    International Nuclear Information System (INIS)

    Tazoe, Makoto; Miyagami, Mitsusuke; Tsubokawa, Takashi

    1991-01-01

    The CT findings of 17 germ cell tumors were studied in relation to the locations of the tumor, the pathological diagnoses, and the tumor markers (AFP and HCG). Generally, the CT findings of germ cell tumors depended on the pathological diagnoses more strongly than on the location of the tumors. On plain CT of 7 germ cell tumors in the pineal region, all of them demonstrated heterogeneous findings. Hydrocephalus was seen in 6 cases (86%) and calcification in 6 cases (86%) of the germ cell tumors in the pineal region. Calcification and hydrocephalus that appeared more often than in other regions were characteristic of germ cell tumors of the pineal region. The germ cell tumors in the basal ganglia had a slightly homogenous high density, with small cysts and calcification in most of them on plain CT. On enhanced CT, the tumors were moderately enhanced in all cases located in the basal ganglia. Four cases of germ cell tumors located in the basal ganglia revealed the dilatation of lateral ventricle due to hemispheric atrophy in the tumor side. The germ cell tumors showing an increase in the tumor markers such as AFP and HCG, which were usually malignant germ cell tumors, were strongly enhanced on enhanced CT. (author)

  8. Insights into female germ cell biology: from in vivo development to in vitro derivations.

    Science.gov (United States)

    Jung, Dajung; Kee, Kehkooi

    2015-01-01

    Understanding the mechanisms of human germ cell biology is important for developing infertility treatments. However, little is known about the mechanisms that regulate human gametogenesis due to the difficulties in collecting samples, especially germ cells during fetal development. In contrast to the mitotic arrest of spermatogonia stem cells in the fetal testis, female germ cells proceed into meiosis and began folliculogenesis in fetal ovaries. Regulations of these developmental events, including the initiation of meiosis and the endowment of primordial follicles, remain an enigma. Studying the molecular mechanisms of female germ cell biology in the human ovary has been mostly limited to spatiotemporal characterizations of genes or proteins. Recent efforts in utilizing in vitro differentiation system of stem cells to derive germ cells have allowed researchers to begin studying molecular mechanisms during human germ cell development. Meanwhile, the possibility of isolating female germline stem cells in adult ovaries also excites researchers and generates many debates. This review will mainly focus on presenting and discussing recent in vivo and in vitro studies on female germ cell biology in human. The topics will highlight the progress made in understanding the three main stages of germ cell developments: namely, primordial germ cell formation, meiotic initiation, and folliculogenesis.

  9. The impact of atmospheric cold plasma treatment on inactivation of lipase and lipoxygenase of wheat germs

    DEFF Research Database (Denmark)

    Tolouie, Haniye; Mohammadifar, Mohammad Amin; Ghomi, Hamid

    2018-01-01

    Wheat germ is a by-product of milling process which contains large amount of nutrients. The shelf life of wheat germ could improve by inactivation of destructive endogenous enzymes especially lipase and lipoxygenase. In this work, the impact of atmospheric cold plasma treatment on the inactivation...... of lipase and lipoxygenase enzymes of wheat germ was studied. Dielectric barrier discharge plasma was utilized to treat wheat germs. The impact of treatment time and voltage of plasma on the inactivation of lipase and lipoxygenase were investigated as well. The higher voltage and treatment time led...

  10. Could vitamin C and zinc chloride protect the germ cells against sodium arsenite?

    Science.gov (United States)

    Altoé, L S; Reis, I B; Gomes, Mlm; Dolder, H; Pirovani, Jc Monteiro

    2017-10-01

    Arsenic (As) is commonly associated with natural and human processes such as volcanic emissions, mining and herbicides production, being an important pollutant. Several studies have associated As intake with male fertility reduction, thus the aim of the present study was to evaluate whether vitamin C and/or zinc would counteract As side effects within the testicles. Adult male Wistar rats were divided into six experimental groups: control, sodium arsenite (5 mg/kg/day), vitamin C (100 mg/kg/day), zinc chloride (ZnCl 2 ; 20 mg/kg/day), sodium arsenite + vitamin C and sodium arsenite + ZnCl 2 . Testicles and epididymis were harvested and either frozen or routinely processed to be embedded in glycol methacrylate resin. As reduced the seminiferous epithelium and tubules diameter due to germ cell loss. In addition, both the round spermatids population and the daily sperm production were reduced. However, ZnCl 2 and vitamin C showed to be effective against such side effects, mainly regarding to sperm morphology. Long-term As intake increased the proportions of abnormal sperm, whereas the concomitant intake of As with zinc or vitamin C enhanced the proportions of normal sperm, showing that such compounds could be used to protect this cell type against morphological defects.

  11. Germ-line mutations at a mouse ESTR (Pc-3) locus and human microsatellite loci

    International Nuclear Information System (INIS)

    Ryo, Haruko; Nakajima, Hiroo; Nomura, Taisei

    2006-01-01

    We examined the use of the mouse Pc-3 ESTR (expanded simple tandem repeat) locus and 72 human microsatellite loci as potentially sensitive biomarkers for mutagenic exposures to germ cells in mice and humans respectively. In the mouse work, we treated male mice with TCDD (2, 3, 7, 8-tetrachlo-rodibenzo-p-dioxin; a chemical known to induce congenital anomalies in humans and mice) and, analysed the F 1 fetuses for Pc-3 mutations. Although the incidence of anomalies was higher in the TCDD group, there were no induced mutations. However, respiratory distress syndrome (RDS) was observed in 3 of 7 fetuses born to male mice which were treated with TCDD and which showed abnormal length of Pc-3 allele. In the human studies, the children of Chernobyl liquidators were examined for mutations at a total of 72 (31 autosomal, 1 X-linked and 40 Y-linked) microsatellite loci. This study was prompted by earlier findings of increases in microsatellite mutations in barn swallows and wheat in the highly contaminated areas after the Chernobyl accident. We examined 64 liquidator families (70 children) and 66 control families (70 children). However, no increases in mutation rates were found. The estimated mean dose to the liquidators was about 39 mSv and this might be one possible reason why no increases of mutations could be found. (author)

  12. Integrative characterization of germ cell-specific genes from mouse spermatocyte UniGene library

    Directory of Open Access Journals (Sweden)

    Eddy Edward M

    2007-07-01

    Full Text Available Abstract Background The primary regulator of spermatogenesis, a highly ordered and tightly regulated developmental process, is an intrinsic genetic program involving male germ cell-specific genes. Results We analyzed the mouse spermatocyte UniGene library containing 2155 gene-oriented transcript clusters. We predict that 11% of these genes are testis-specific and systematically identified 24 authentic genes specifically and abundantly expressed in the testis via in silico and in vitro approaches. Northern blot analysis disclosed various transcript characteristics, such as expression level, size and the presence of isoform. Expression analysis revealed developmentally regulated and stage-specific expression patterns in all of the genes. We further analyzed the genes at the protein and cellular levels. Transfection assays performed using GC-2 cells provided information on the cellular characteristics of the gene products. In addition, antibodies were generated against proteins encoded by some of the genes to facilitate their identification and characterization in spermatogenic cells and sperm. Our data suggest that a number of the gene products are implicated in transcriptional regulation, nuclear integrity, sperm structure and motility, and fertilization. In particular, we found for the first time that Mm.333010, predicted to contain a trypsin-like serine protease domain, is a sperm acrosomal protein. Conclusion We identify 24 authentic genes with spermatogenic cell-specific expression, and provide comprehensive information about the genes. Our findings establish a new basis for future investigation into molecular mechanisms underlying male reproduction.

  13. Foxn1[Cre] Expression in the Male Germline.

    Science.gov (United States)

    Shi, Jianjun; Getun, Irina; Torres, Bivian; Petrie, Howard T

    2016-01-01

    Foxn1 (forkhead box N1), also known as the nude gene or winged-helix nude (Whn), is a forkhead transcription factor thought to be restricted to keratinocytes in the skin and thymus. Consistent with this tissue distribution, spontaneous or targeted mutation of Foxn1 results in the absence of both hair and a thymus. Genetic manipulation of the Foxn1 locus thus represents a powerful tool for tissue specific gene control in the skin and thymus, and tools such as Cre recombinase under control of the Foxn1 locus are widely used for this purpose. Unexpectedly, we show that Foxn1[Cre] exhibits unexpected activity in male germ cells, resulting in ubiquitous targeting of loxP-flanked alleles in all tissues in offspring from Foxn1[Cre] expressing male mice. Inheritance of recombined loxP alleles occurs independently of Cre inheritance (i.e., offspring lacking Cre nonetheless exhibit recombined alleles), suggesting that Foxn1[Cre] induced recombination in male germ cells must occur prior to meiosis in diploid germ cells. Together with previously published data, our results show that Foxn1, and alleles under its control, are expressed in the pre-meiotic male germline, revealing a new tool for germline targeting of genes, and raising important concerns for gender selection when using Foxn1 regulatory elements.

  14. [Impact of zearalenone on male fertility: An update].

    Science.gov (United States)

    Pang, Jian; Cao, Quan-Fu; Sun, Zhong-Yi

    2016-11-01

    Zearalenone (ZEA) is a nonsteroidal estrogen-like mycotoxin widely distributed in maize, wheat, rice and other cereals with its derivants. It also presents in meat or dairy products or even in the aquatic ecosystem via rain, and thus can affect human health. ZEA affects the body function in various ways. On the one hand, it can disturb the synthesis of estrogen and its combination with the receptor, influence the reproductive ability via the estrogen signaling pathway, and cause the dysfunction of the reproductive systems. On the other hand, it can disturb the synthesis of DNA and proteins and result in lipid peroxidation and cytotoxicity by inducing the apoptosis of germ cells. It is known that exposure to different doses of ZEA can affect the female reproductive system by increasing the apoptosis of germ cells and inducing germ cell prematurity, sexual precocity, endocrine disorder, reproductive cycle disorder, and so on. But studies of its influence on the male reproductive system are relatively rare, especially about its unique male-related action mechanisms. This review presents an overview of the studies on the mechanisms of ZEA affecting male fertility and the phenotype changes in the male reproductive system after exposure to ZEA, hoping to provide some new ideas for the protection of human fertility.

  15. Gods, Germs, and Petri Dishes: Toward a Nonsecular Medical Anthropology.

    Science.gov (United States)

    Roberts, Elizabeth F S

    2016-01-01

    This commentary calls on medical anthropology to become programmatically non-secular. Despite recent anthropological critiques of secularity, within and outside of anthropology, most contemporary medical anthropologists continue to leave deities and religiosity out of their examinations of healing practices, especially in their accounts of biomedicine. Through a critical, relational constructionist lens, which traces how all entities are both constructed and real, a non-secular medical anthropology would insist that when deities are part of medical practice, they are integral to analysis. Importantly then, within the symmetrical nature of this same constructionist lens, biomedical entities like germs and petri dishes need to be accounted for just as much as deities.

  16. In utero bisphenol A exposure disrupts germ cell nest breakdown and reduces fertility with age in the mouse

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei, E-mail: weiwang2@illinois.edu; Hafner, Katlyn S., E-mail: katlynhafner@gmail.com; Flaws, Jodi A., E-mail: jflaws@illinois.edu

    2014-04-15

    Bisphenol A (BPA) is a known reproductive toxicant in rodents. However, the effects of in utero BPA exposure on early ovarian development and the consequences of such exposure on female reproduction in later reproductive life are unclear. Thus, we determined the effects of in utero BPA exposure during a critical developmental window on germ cell nest breakdown, a process required for establishment of the finite primordial follicle pool, and on female reproduction. Pregnant FVB mice (F0) were orally dosed daily with tocopherol-striped corn oil (vehicle), diethylstilbestrol (DES; 0.05 μg/kg, positive control), or BPA (0.5, 20, and 50 μg/kg) from gestational day 11 until birth. Ovarian morphology and gene expression profiles then were examined in F1 female offspring on postnatal day (PND) 4 and estrous cyclicity was examined daily after weaning for 30 days. F1 females were also subjected to breeding studies with untreated males at three to nine months. The results indicate that BPA inhibits germ cell nest breakdown via altering expression of selected apoptotic factors. BPA also significantly advances the age of first estrus, shortens the time that the females remain in estrus, and increases the time that the females remain in metestrus and diestrus compared to controls. Further, F1 females exposed to low doses of BPA exhibit various fertility problems and have a significantly higher percentage of dead pups compared to controls. These results indicate that in utero exposure to low doses of BPA during a critical ovarian developmental window interferes with early ovarian development and reduces fertility with age. - Highlights: • In utero BPA exposure inhibits germ cell nest breakdown in female mouse offspring. • In utero BPA exposure alters expression of apoptosis regulators in the ovaries of mouse offspring. • In utero BPA exposure advances first estrus age and alters cyclicity in mouse offspring. • In utero BPA exposure causes various fertility problems in

  17. In utero bisphenol A exposure disrupts germ cell nest breakdown and reduces fertility with age in the mouse

    International Nuclear Information System (INIS)

    Wang, Wei; Hafner, Katlyn S.; Flaws, Jodi A.

    2014-01-01

    Bisphenol A (BPA) is a known reproductive toxicant in rodents. However, the effects of in utero BPA exposure on early ovarian development and the consequences of such exposure on female reproduction in later reproductive life are unclear. Thus, we determined the effects of in utero BPA exposure during a critical developmental window on germ cell nest breakdown, a process required for establishment of the finite primordial follicle pool, and on female reproduction. Pregnant FVB mice (F0) were orally dosed daily with tocopherol-striped corn oil (vehicle), diethylstilbestrol (DES; 0.05 μg/kg, positive control), or BPA (0.5, 20, and 50 μg/kg) from gestational day 11 until birth. Ovarian morphology and gene expression profiles then were examined in F1 female offspring on postnatal day (PND) 4 and estrous cyclicity was examined daily after weaning for 30 days. F1 females were also subjected to breeding studies with untreated males at three to nine months. The results indicate that BPA inhibits germ cell nest breakdown via altering expression of selected apoptotic factors. BPA also significantly advances the age of first estrus, shortens the time that the females remain in estrus, and increases the time that the females remain in metestrus and diestrus compared to controls. Further, F1 females exposed to low doses of BPA exhibit various fertility problems and have a significantly higher percentage of dead pups compared to controls. These results indicate that in utero exposure to low doses of BPA during a critical ovarian developmental window interferes with early ovarian development and reduces fertility with age. - Highlights: • In utero BPA exposure inhibits germ cell nest breakdown in female mouse offspring. • In utero BPA exposure alters expression of apoptosis regulators in the ovaries of mouse offspring. • In utero BPA exposure advances first estrus age and alters cyclicity in mouse offspring. • In utero BPA exposure causes various fertility problems in

  18. Melatonin receptor genes (mel-1a, mel-1b, mel-1c) are differentially expressed in the avian germ line.

    Science.gov (United States)

    Kawashima, Takaharu; Stepińska, Urszula; Kuwana, Takashi; Olszańska, Bozenna

    2008-09-01

    The presence of melatonin receptor transcripts (mel-1a, mel-1b and mel-1c) was investigated in primordial germ cells (PGCs), immature and mature oocytes, and sperm of Japanese quail by reverse transcription--polymerase chain reaction (RT-PCR). The mel-1a transcript was detected in as few as in a thousand PGCs. Significant differences in the expression of melatonin receptor genes were found in differentiating germ cells: in PGCs only the mel-1a receptor was expressed, in blastoderms and immature oocytes all three transcripts (mel-1a, mel-1b, mel-1c) were present, while in mature ovulated oocytes the predominant transcript was mel-1c (with sporadic occurrence of mel-1a and mel-1b). In sperm, mel-1a and mel-1c were present but mel-1b was absent. This indicates that the expression of melatonin receptor genes changes throughout the differentiation of PGCs into adult gametes: during oocyte differentiation two additional transcripts, mel-1b and mel-1c, are synthesized in addition to mel-1a, but at oocyte maturation, mel-1a and mel-1b are degraded and only mel-1c remains. During male line (spermatozoa) differentiation mel-1c is transcribed in addition to mel-1a, with mel-1b being completely absent. Since melatonin and the activities of enzymes participating in melatonin synthesis are present in the avian yolk, it is reasonable to suggest a role for this molecule in early avian development and germ line differentiation. We propose that melatonin may act as a signaling molecule regulating some differentiation processes (e.g., cell proliferation, migration, etc.) before the formation of neural and hormonal systems.

  19. Male Hypogonadism

    Science.gov (United States)

    ... the hormone that plays a key role in masculine growth and development during puberty — or has an ... Adulthood In adult males, hypogonadism may alter certain masculine physical characteristics and impair normal reproductive function. Signs ...

  20. Male Infertility

    Science.gov (United States)

    ... to have a baby? If treatment doesn’t work, what are our other options? Resources National Institute of Child Health and Human Development, What Causes Male Infertility? Last Updated: May 30, 2017 This ...

  1. Male contraception.

    Science.gov (United States)

    Amory, John K

    2016-11-01

    Although female contraceptives are very effective at preventing unintended pregnancy, some women can not use them because of health conditions or side-effects, leaving some couples without effective contraceptive options. In addition, many men wish to take active responsibility for family planning. Thus, there is a great need for male contraceptives to prevent unintended pregnancies, of which 80-90 million occur annually. At present, effective male contraceptive options are condoms and vasectomy, which are not ideal for all men. Therefore, efforts are under way to develop novel male contraceptives. This paper briefly reviews the advantages and disadvantages of condoms and vasectomies and then discusses the research directed toward development of novel methods of male contraception. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  2. Condoms - male

    Science.gov (United States)

    Prophylactics; Rubbers; Male condoms; Contraceptive - condom; Contraception - condom; Barrier method - condom ... your health care provider or pharmacy about emergency contraception ("morning-after pills"). PROBLEMS WITH CONDOM USE Some ...

  3. Male contraception

    OpenAIRE

    Mathew, Vivek; Bantwal, Ganapathi

    2012-01-01

    Contraception is an accepted route for the control of population explosion in the world. Traditionally hormonal contraceptive methods have focused on women. Male contraception by means of hormonal and non hormonal methods is an attractive alternative. Hormonal methods of contraception using testosterone have shown good results. Non hormonal reversible methods of male contraception like reversible inhibition of sperm under guidanceare very promising. In this article we have reviewed the curren...

  4. Male sexuality.

    Science.gov (United States)

    Ginsberg, Terrie B

    2010-05-01

    It should be recognized that sexuality in the aging male is of such import that a complete sexual history must be performed. By taking a complete sexual history, facts can be obtained that will allow for appropriate focus relating to a holistic evaluation and will enable us to dispel antiquated sexual myths pertaining to the aging male. If initiated by the history taker, questions concerning sexuality may be discussed more comfortably by the patient. Erectile dysfunction, male sexual response cycle, testosterone, sexually transmitted diseases, human immunodeficiency virus, long-term illness, along with religion and culture are explored in this article with the aim of improving one's knowledge base, self reflection, and awareness of the importance of male sexuality. A complete understanding and appreciation of the aging male's medical history, surgical history, social history, and emotional history as well as his sexual, cultural, and religious concepts will allow the health care provider to better analyze information, and to recommend and provide appropriate advice and treatment to the aging male patient. Copyright 2010 Elsevier Inc. All rights reserved.

  5. Phenotypic diversity of diploid and haploid Emiliania huxleyi cells and of cells in different growth phases revealed by comparative metabolomics.

    Science.gov (United States)

    Mausz, Michaela A; Pohnert, Georg

    2015-01-01

    In phytoplankton a high species diversity of microalgae co-exists at a given time. But diversity is not only reflected by the species composition. Within these species different life phases as well as different metabolic states can cause additional diversity. One important example is the coccolithophore Emiliania huxleyi. Diploid cells play an important role in marine ecosystems since they can form massively abundant algal blooms but in addition the less abundant haploid life phase of E. huxleyi occurs in lower quantities. Both life phases may fulfill different functions in the plankton. We hypothesize that in addition to the functional diversity caused by this life phase transition the growth stage of cells can also influence the metabolic composition and thus the ecological impact of E. huxleyi. Here we introduce a metabolomic survey in dependence of life phases as well as different growth phases to reveal such changes. The comparative metabolomic approach is based on the extraction of intracellular metabolites from intact microalgae, derivatization and analysis by gas chromatography coupled to mass spectrometry (GC-MS). Automated data processing and statistical analysis using canonical analysis of principal coordinates (CAP) revealed unique metabolic profiles for each life phase. Concerning the correlations of metabolites to growth phases, complex patterns were observed. As for example the saccharide mannitol showed its highest concentration in the exponential phase, whereas fatty acids were correlated to stationary and sterols to declining phase. These results are indicative for specific ecological roles of these stages of E. huxleyi and are discussed in the context of previous physiological and ecological studies. Copyright © 2014 Elsevier GmbH. All rights reserved.

  6. In vivo evolutionary engineering for ethanol-tolerance of Saccharomyces cerevisiae haploid cells triggers diploidization.

    Science.gov (United States)

    Turanlı-Yıldız, Burcu; Benbadis, Laurent; Alkım, Ceren; Sezgin, Tuğba; Akşit, Arman; Gökçe, Abdülmecit; Öztürk, Yavuz; Baykal, Ahmet Tarık; Çakar, Zeynep Petek; François, Jean M

    2017-09-01

    Microbial ethanol production is an important alternative energy resource to replace fossil fuels, but at high level, this product is highly toxic, which hampers its efficient production. Towards increasing ethanol-tolerance of Saccharomyces cerevisiae, the so far best industrial ethanol-producer, we evaluated an in vivo evolutionary engineering strategy based on batch selection under both constant (5%, v v -1 ) and gradually increasing (5-11.4%, v v -1 ) ethanol concentrations. Selection under increasing ethanol levels yielded evolved clones that could tolerate up to 12% (v v -1 ) ethanol and had cross-resistance to other stresses. Quite surprisingly, diploidization of the yeast population took place already at 7% (v v -1 ) ethanol level during evolutionary engineering, and this event was abolished by the loss of MKT1, a gene previously identified as being implicated in ethanol tolerance (Swinnen et al., Genome Res., 22, 975-984, 2012). Transcriptomic analysis confirmed diploidization of the evolved clones with strong down-regulation in mating process, and in several haploid-specific genes. We selected two clones exhibiting the highest viability on 12% ethanol, and found productivity and titer of ethanol significantly higher than those of the reference strain under aerated fed-batch cultivation conditions. This higher fermentation performance could be related with a higher abundance of glycolytic and ribosomal proteins and with a relatively lower respiratory capacity of the evolved strain, as revealed by a comparative transcriptomic and proteomic analysis between the evolved and the reference strains. Altogether, these results emphasize the efficiency of the in vivo evolutionary engineering strategy for improving ethanol tolerance, and the link between ethanol tolerance and diploidization. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  7. A haploid genetic screen identifies the G1/S regulatory machinery as a determinant of Wee1 inhibitor sensitivity.

    Science.gov (United States)

    Heijink, Anne Margriet; Blomen, Vincent A; Bisteau, Xavier; Degener, Fabian; Matsushita, Felipe Yu; Kaldis, Philipp; Foijer, Floris; van Vugt, Marcel A T M

    2015-12-08

    The Wee1 cell cycle checkpoint kinase prevents premature mitotic entry by inhibiting cyclin-dependent kinases. Chemical inhibitors of Wee1 are currently being tested clinically as targeted anticancer drugs. Wee1 inhibition is thought to be preferentially cytotoxic in p53-defective cancer cells. However, TP53 mutant cancers do not respond consistently to Wee1 inhibitor treatment, indicating the existence of genetic determinants of Wee1 inhibitor sensitivity other than TP53 status. To optimally facilitate patient selection for Wee1 inhibition and uncover potential resistance mechanisms, identification of these currently unknown genes is necessary. The aim of this study was therefore to identify gene mutations that determine Wee1 inhibitor sensitivity. We performed a genome-wide unbiased functional genetic screen in TP53 mutant near-haploid KBM-7 cells using gene-trap insertional mutagenesis. Insertion site mapping of cells that survived long-term Wee1 inhibition revealed enrichment of G1/S regulatory genes, including SKP2, CUL1, and CDK2. Stable depletion of SKP2, CUL1, or CDK2 or chemical Cdk2 inhibition rescued the γ-H2AX induction and abrogation of G2 phase as induced by Wee1 inhibition in breast and ovarian cancer cell lines. Remarkably, live cell imaging showed that depletion of SKP2, CUL1, or CDK2 did not rescue the Wee1 inhibition-induced karyokinesis and cytokinesis defects. These data indicate that the activity of the DNA replication machinery, beyond TP53 mutation status, determines Wee1 inhibitor sensitivity, and could serve as a selection criterion for Wee1-inhibitor eligible patients. Conversely, loss of the identified S-phase genes could serve as a mechanism of acquired resistance, which goes along with development of severe genomic instability.

  8. Male-mediated developmental toxicity

    International Nuclear Information System (INIS)

    Anderson, Diana

    2005-01-01

    In recent years, the public has become more aware that exposure of males to certain agents can adversely affect their offspring and cause infertility and cancer. The hazards associated with exposure to ionising radiation have been recognised for nearly a century, but interest was aroused when a cluster of leukaemia cases was identified in young children living in Seascale, close to the nuclear processing plant at Sellafield in West Cumbria. There was a civil court case on behalf of two of the alleged victims of paternal irradiation at Seascale against British Nuclear Fuels. The case foundered on 'the balance of probabilities'. Nevertheless, there was support for paternal exposure from Japanese experimental X-ray studies in mice. The tumours were clearly heritable as shown by F2 transmission. Also, effects of a relatively non-toxic dose of radiation (1Gy) on cell proliferation transmitted to the embryo were manifested in the germ line of adult male mice even after two generations. In addition in humans, smoking fathers appear to give rise to tumours in the F 1 generation. Using rodent models, developmental abnormalities/congenital malformations and tumours can be studied after exposure of males in an extended dominant lethal assay and congenital malformations can be determined which have similar manifestations in humans. The foetuses can also be investigated for skeletal malformations and litters can be allowed to develop to adulthood when tumours, if present, can be observed. Karyotype analysis can be performed on foetuses and adult offspring to determine if induced genetic damage can be transmitted. Using this study design, cyclophosphamide, 1,3-butadiene and urethane have been examined and each compound produced positive responses: cyclophosphamide in all endpoints examined, 1,3-butadiene in some and urethane only produced liver tumours in F 1 male offspring. This suggests the endpoints are determined by independent genetic events. The results from heritable

  9. Issues in identifying germ tube positive yeasts by conventional methods.

    Science.gov (United States)

    Yazdanpanah, Atta; Khaithir, Tzar Mohd Nizam

    2014-01-01

    Candida speciation is vital for epidemiology and management of candidiasis. Nonmolecular conventional methods often fail to identify closely related germ tube positive yeasts from clinical specimens. The present study was conducted to identify these yeasts and to highlight issues in conventional versus molecular methods of identification. A total of 98 germ tube positive yeasts from high vaginal swabs were studied over a 12-month period. Isolates were examined with various methods including growth at 42 °C and 45 °C on Sabouraud dextrose agar (SDA), color development on CHROMagar Candida medium, chlamydospore production on corn meal agar at 25 °C, carbohydrate assimilation using ID 32C system, and polymerase chain reaction using a single pair of primers targeting the hyphal wall protein 1 (Hwp1) gene. Of all the isolates studied, 97 were molecularly confirmed as C. albicans and one isolate was identified as C. dubliniensis. No C. africana was detected in this study. The molecular method used in our study was an accurate and useful tool for discriminating C. albicans, C. dubliniensis, and C. africana. The conventional methods, however, were less accurate and riddled with many issues that will be discussed in further details. © 2013 Wiley Periodicals, Inc.

  10. Erythropoietin may reduce the risk of germ cell loss in boys with cryptorchidism

    DEFF Research Database (Denmark)

    Cortes, Dina; Visfeldt, J; Thorup, J M

    2001-01-01

    In boys with cryptorchidism older than 2 years a testicular biopsy at time of orchiopexy shows lack of germ cells in 10-40% of the cases. The number of spermatogonia per tubule is prognostic for subsequent fertility potential. A biopsy without germ cells is associated with 33-100% risk of inferti...

  11. Orientation of Germ Tubes of Puccinia hordei on the Hordeum chilense Leaf Surface

    NARCIS (Netherlands)

    Vaz Patto, M.C.; Niks, R.E.

    2000-01-01

    The directional growth of urediospores germ tubes along the transverse axis of a cereal's leaf is considered to be a response to stimuli from the plant surface. In order to find out if the germ tube growth is directed towards stomata, and if the cuticular wax layer plays a role in this orientated

  12. Influence of different dose irradiation on genetic effect in mice somatic and germ cells

    International Nuclear Information System (INIS)

    Kostrova, L.N.; Molofej, V.P.; Mosseh, I.B.

    2007-01-01

    Comparison of clastogenic effects of different radiation doses in somatic and germ cells of one the same animals has been studied. Correlation analysis allows to extrapolate genetic effects from somatic cells to germ ones. This can be useful for human model elaboration. (authors)

  13. Prevention of airborne contamination and cross-contamination in germ-free mice by laminar flow

    NARCIS (Netherlands)

    Waaij, D. van der; Andres, A.H.

    1971-01-01

    The efficacy of horizontal and vertical laminar flow units (equipped with high-efficiency air filters) in the prevention of cross-contamination between cages and of contamination from outside has been demonstrated. With germ-free mice and using germ-free standard techniques for sterilization and for

  14. Weierstrass preparation and division theorems for the ring of germs of superanalytic functions

    International Nuclear Information System (INIS)

    Yankov, C.L.

    1989-11-01

    The aim of this paper is to show that Weierstrass preparation and division theorems hold for the ring of germs of superanalytic functions at a given point. This ring is the tensor product of the ring of germs of analytic functions at that point and a finite-dimensional complex Grassmann algebra. 7 refs

  15. Risk and prognostic significance of metachronous contralateral testicular germ cell tumours

    NARCIS (Netherlands)

    Schaapveld, M.; van den Belt-Dusebout, A. W.; Gietema, J. A.; de Wit, R.; Horenblas, S.; Witjes, J. A.; Hoekstra, H. J.; Kiemeney, L. A. L. M.; Louwman, W. J.; Ouwens, G. M.; Aleman, B. M. P.; van Leeuwen, F. E.

    2012-01-01

    BACKGROUND: Testicular germ cell tumour (TGCT) patients are at increased risk of developing a contralateral testicular germ cell tumour (CTGCT). It is unclear whether TGCT treatment affects CTGCT risk. METHODS: The risk of developing a metachronous CTGCT (a CTGCT diagnosed >= 6 months after a

  16. Primary Germ Cell Tumors of the Mediastinum: 10 Years of Experience in a Tertiary Teaching Hospital

    Directory of Open Access Journals (Sweden)

    Chih-Jen Yang

    2005-09-01

    Full Text Available Germ cell tumors occur mostly in the gonad. Extragonadal germ cell tumors are rare, and most occur in the retroperitoneum and mediastinum. Primary mediastinal germ cell tumors are often found in the anterior portion of the mediastinum and include teratomas and non-teratomatous tumors. Non-teratomatous tumors include seminomas and malignant non-seminomatous germ cell tumors (MNSGCTs. MNSGCTs include yolk sac tumors, choriocarcinomas, embryonal carcinomas, and mixed type germ cell tumors. Teratomas are the most common germ cell tumors of the mediastinum, and seminomas are the most common non-teratomatous germ cell tumors of the mediastinum. Cases of primary mediastinal MNSGCT reported in the literature are rare. In this report, we review all primary mediastinal germ cell tumors from a 10-year period at the Chung-Ho Memorial Hospital of Kaohsiung Medical University. A total of 14 cases were reviewed, including 11 patients with mature teratomas, two with yolk sac tumors, and one with seminoma. We discuss the differences in clinical presentation, histopathologic characteristics, treatment, and prognosis.

  17. Childhood Central Nervous System Germ Cell Tumors Treatment (PDQ®)—Health Professional Version

    Science.gov (United States)

    CNS germ cell tumors can be diagnosed and classified based on histology, tumor markers, or a combination of both. Get detailed information about newly diagnosed and recurrent childhood CNS germ cell tumors including molecular features and clinical features, diagnostic and staging evaluation, and treatment in this summary for clinicians.

  18. Dafachronic acid inhibits C. elegans germ cell proliferation in a DAF-12-dependent manner.

    Science.gov (United States)

    Mukherjee, Madhumati; Chaudhari, Snehal N; Balachandran, Riju S; Vagasi, Alexandra S; Kipreos, Edward T

    2017-12-15

    Dafachronic acid (DA) is a bile acid-like steroid hormone that regulates dauer formation, heterochrony, and lifespan in C. elegans. Here, we describe that DA is an inhibitor of C. elegans germ stem cell proliferation in adult hermaphrodites. Using a C. elegans germ cell primary culture system, we show that DA inhibits the proliferation of germ cells in vitro. Exogenous DA reduces the frequency of large tumors in adult tumorous germline mutants and decreases the proliferation of wild-type germ stem cells in adult hermaphrodites. In contrast, DA has no appreciable effect on the proliferation of larval-stage germ cells in wild type. The inhibition of adult germ cell proliferation by DA requires its canonical receptor DAF-12. Blocking DA production by inactivating the cytochrome P450 DAF-9 increases germ cell proliferation in wild-type adult hermaphrodites and the frequency of large tumors in germline tumorous mutants, suggesting that DA inhibits the rate of germ cell proliferation under normal growth conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. [Serum hormones that regulate the reproductive axis in men with testicular germ cell cancer and its impact on fertility].

    Science.gov (United States)

    Tovar-Rodríguez, José María; Chávez-Zúñiga, Irma; Bañuelos-Ávila, Leticia; Vargas-Hernández, Víctor Manuel; Acosta-Altamirano, Gustavo

    2014-01-01

    Epidemiological studies treat testicular germ cancer as a single disease, the behavior of the two histological types of cancer; seminoma and nonseminoma have differences in reproductive hormone secretion and impair fertility differently. To demonstrate that the serum concentration of pituitary hormones involved in fertility and spermatogenesis in the affected male is different in the two histological types. Were determined by radioimmunoassay or inmunoradiometric assay, luteinizing hormone, follicle stimulating hormone, total testosterone, prolactin, estradiol, human chorionic gonadotropin and alpha fetoprotein in 37 patients with germ cell cancer (15 seminoma and 22 nonseminoma) and 35 controls. We analyzed the semen of patients, and were questioned about paternity before the cancer diagnosis. Age was higher in patients with seminoma cancer, showed decreased luteinizing hormone, follicle stimulating hormone, and testosterone and increased estradiol and prolactin in nonseminoma compared with seminoma. In patients with nonseminoma they had 9 children, 5 were oligozoospermic, 3 azoospermic and 6 normal concentration, 8 did not provide sample, seminoma group they had eight children, only one azoospermic, nine normal concentration, and 5 did not provide sample . The hormonal behavior is different in men with nonseminoma compared with seminoma, so that the negative impact on the reproductive axis and fertility is higher in cases of non-seminoma.

  20. Effect of mode of administration of methyl methanesulfonate and triethylenemelamine on induction of unscheduled DNA synthesis in mouse germ cells

    International Nuclear Information System (INIS)

    Sheu, C.W.; Sega, G.A.; Owens, J.G.

    1987-01-01

    The effect of route of administration on induction of unscheduled DNA synthesis (UDS) in mouse germ cells in vivo was studied using two germ cell mutagens, methyl methanesulfonate (MMS) and triethylenemelamine (TEM). The chemicals were administered to male mice (C3Hf x 101)F 1 by IP injection or gavage using acute or 5-day subacute regimens. After completion of dosing, methyl-[ 3 H]thymidine ([ 3 H]TdR) was injected into the testes, and spermatozoa were collected 16 days later. The sperm heads were isolated, and UDS was determined by the amount of [ 3 H]TdR incorporated. Acute administration of MMS (2-100 mg/kg) induced a strong, dose-related UDS response. The response was slightly higher with IP injection than with gavage. Acute administration of TEM (0.05-4.0 mg/kg) by IP injection or gavage induced weak and variable responses. The study showed that gavage, as well as IP injection, can be used for the administration of test chemicals and that the subacute 5-day regimen induced a higher UDS response than the acute regimen. Furthermore, the testicular route may enhance the detection of weak UDS inducers

  1. Germ cell regeneration-mediated, enhanced mutagenesis in the ascidian Ciona intestinalis reveals flexible germ cell formation from different somatic cells.

    Science.gov (United States)

    Yoshida, Keita; Hozumi, Akiko; Treen, Nicholas; Sakuma, Tetsushi; Yamamoto, Takashi; Shirae-Kurabayashi, Maki; Sasakura, Yasunori

    2017-03-15

    The ascidian Ciona intestinalis has a high regeneration capacity that enables the regeneration of artificially removed primordial germ cells (PGCs) from somatic cells. We utilized PGC regeneration to establish efficient methods of germ line mutagenesis with transcription activator-like effector nucleases (TALENs). When PGCs were artificially removed from animals in which a TALEN pair was expressed, somatic cells harboring mutations in the target gene were converted into germ cells, this germ cell population exhibited higher mutation rates than animals not subjected to PGC removal. PGC regeneration enables us to use TALEN expression vectors of specific somatic tissues for germ cell mutagenesis. Unexpectedly, cis elements for epidermis, neural tissue and muscle could be used for germ cell mutagenesis, indicating there are multiple sources of regenerated PGCs, suggesting a flexibility of differentiated Ciona somatic cells to regain totipotency. Sperm and eggs of a single hermaphroditic, PGC regenerated animal typically have different mutations, suggesting they arise from different cells. PGCs can be generated from somatic cells even though the maternal PGCs are not removed, suggesting that the PGC regeneration is not solely an artificial event but could have an endogenous function in Ciona. This study provides a technical innovation in the genome-editing methods, including easy establishment of mutant lines. Moreover, this study suggests cellular mechanisms and the potential evolutionary significance of PGC regeneration in Ciona. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Male baldness.

    Science.gov (United States)

    Clarke, Philip

    2016-04-01

    Male baldness is very common. Its effect on individuals is extremely variable, and in some people it will have a significant adverse effect on their quality of life. The objectives of this article are to help general practitioners (GPs) be aware of potential health problems related to male baldness, to have an approach to assessing hair loss and to be aware of treatment options. Male baldness is, most often, a normal occurrence, but it may have significant effects on a man's health. It may also be a pointer to other potential health issues. The GP is in the ideal position to conduct an initial evaluation, consider other health issues and advise on treatment options.

  3. Multiplicity of Buc copies in Atlantic salmon contrasts with loss of the germ cell determinant in primates, rodents and axolotl

    OpenAIRE

    Skugor, Adrijana; Tveiten, Helge; Johnsen, Hanne; Andersen, Øivind

    2016-01-01

    Background The primordial germ cells (PGCs) giving rise to gametes are determined by two different mechanisms in vertebrates. While the germ cell fate in mammals and salamanders is induced by zygotic signals, maternally delivered germ cell determinants specify the PGCs in birds, frogs and teleost fish. Assembly of the germ plasm in the oocyte is organized by the single Buc in zebrafish, named Velo1 in Xenopus, and by Oskar in Drosophila. Secondary loss of oskar in several insect lineages coin...

  4. From Young Children's Ideas about Germs to Ideas Shaping a Learning Environment

    Science.gov (United States)

    Ergazaki, Marida; Saltapida, Konstantina; Zogza, Vassiliki

    2010-11-01

    This paper is concerned with highlighting young children’s ideas about the nature, location and appearance of germs, as well as their reasoning strands about germs’ ontological category and biological functions. Moreover, it is concerned with exploring how all these could be taken into account for shaping a potentially fruitful learning environment. Conducting individual, semi-structured interviews with 35 preschoolers (age 4.5-5.5) of public kindergartens in the broader area of Patras, we attempted to trace their ideas about what germs are, where they may be found, whether they are good or bad and living or non-living and how they might look like in a drawing. Moreover, children were required to attribute a series of biological functions to dogs, chairs and germs, and finally to create a story with germs holding a key-role. The analysis of our qualitative data within the “NVivo” software showed that the informants make a strong association of germs with health and hygiene issues, locate germs mostly in our body and the external environment, are not familiar with the ‘good germs’-idea, and draw germs as ‘human-like’, ‘animal-like’ or ‘abstract’ entities. Moreover, they have significant difficulties not only in employing biological functions as criteria for classifying germs in the category of ‘living’, but also in just attributing such functions to germs using a warrant. Finally, the shift from our findings to a 3-part learning environment aiming at supporting preschoolers in refining their initial conceptualization of germs is thoroughly discussed in the paper.

  5. Wheat germ oil enrichment in broiler feed with α-lipoic acid to enhance the antioxidant potential and lipid stability of meat

    Science.gov (United States)

    2013-01-01

    Background Lipid peroxidation is the cause of declining the meat quality. Natural antioxidants plays a vital role in enhancing the stability and quality of meat. The supplementation of natural antioxidants in feed decreases lipid peroxidation and improves the stability of meat. Methods The present research was conducted to determine the effect of α-lipoic acid, α-tocopherol and wheat germ oil on the status of antioxidants, quality and lipid stability of broiler meat. One day old male broilers were fed with different feeds containing antioxidants i.e. natural (wheat germ oil) and synthetic α-tocopherol and α-lipoic acid during the two experimental years. Results The feed treatments have significant variation on the body weight and feed conversion ratio (FCR) while having no influence on the feed intake. The broilers fed on wheat germ oil (natural α-tocopherol) gained maximum body weight (2451.97 g & 2466.07 g) in the experimental years 2010–11 & 2011–12, respectively. The higher total phenolic contents were found in the broilers fed on wheat germ oil plus α-lipoic acid in breast (162.73±4.8 mg Gallic acid equivalent/100 g & 162.18±4.5 mg Gallic acid equivalent/100 g) and leg (149.67±3.3 mg Gallic acid equivalent/100 g & 146.07±3.2 mg Gallic acid equivalent/100 g) meat during both experimental years. Similar trend was observed for the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power assay (FRAP). The production of malondialdehydes in the breast and leg meat increased with progressive increase in the time period. The deposition of α-tocopherol (AT) and α-lipoic acid (ALA) contents were found to be higher in the broilers fed on wheat germ oil plus α-lipoic acid in breast and leg meat during the both experimental years. Conclusion In conclusion, the combination of wheat germ oil and α-lipoic acid has more beneficial for stability and the quality of the broiler meat and more work should be needed in future for the bio

  6. Location of bladder and urethral sphincter motoneurons in the male guinea pig (Cavia porcellus)

    NARCIS (Netherlands)

    Kuipers, R; Izhar, Z; Gerrits, PO; Miner, W; Holstege, G; Gerrits, Peter O.

    2004-01-01

    Although the guinea pig is used widely in experimental medical research, including in studies on micturition control, the spinal origin of preganglionic parasympathetic bladder and somatic external urethral sphincter motoneurons is not known. In the male, guinea pig using wheat germ

  7. Male-mediated spontaneous abortion among spouses of stainless steel welders

    DEFF Research Database (Denmark)

    Hjollund, N H; Bonde, J P; Jensen, T K

    2000-01-01

    Male-mediated spontaneous abortion has never been documented for humans. The welding of stainless steel is associated with the pulmonary absorption of hexavalent chromium, which has genotoxic effects on germ cells in rodents. Clinical and early subclinical spontaneous abortions were examined among...

  8. Clinical use of serum TRA-1-60 as tumor marker in patients with germ cell cancer

    DEFF Research Database (Denmark)

    Lajer, Henrik; Daugaard, Gedske; Andersson, Anna-Maria

    2002-01-01

    TRA-1-60 antigen has been related to the presence of embryonal germ cell carcinoma (EC) and carcinoma in situ. Our study further investigated the clinical efficacy of TRA-1-60 as a serum tumor marker for germ cell cancer in the testis. Three groups of patients with germ cell tumors were included:...

  9. File list: InP.Gon.10.AllAg.Testicular_germ_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Gon.10.AllAg.Testicular_germ_cells mm9 Input control Gonad Testicular germ cell.../dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Gon.10.AllAg.Testicular_germ_cells.bed ...

  10. Nanosecond pulsed electric field suppresses development of eyes and germ cells through blocking synthesis of retinoic acid in Medaka (Oryzias latipes.

    Directory of Open Access Journals (Sweden)

    Eri Shiraishi

    Full Text Available Application of nanosecond pulsed electric fields (nsPEFs has attracted rising attention in various scientific fields including medical, pharmacological, and biological sciences, although its effects and molecular mechanisms leading to the effects remain poorly understood. Here, we show that a single, high-intensity (10-30 kV/cm, 60-ns PEF exposure affects gene expression and impairs development of eyes and germ cells in medaka (Oryzias latipes. Exposure of early blastula stage embryos to nsPEF down-regulated the expression of several transcription factors which are essential for eye development, causing abnormal eye formation. Moreover, the majority of the exposed genetic female embryos showed a fewer number of germ cells similar to that of the control (unexposed genetic male at 9 days post-fertilization (dpf. However, all-trans retinoic acid (atRA treatment following the exposure rescued proliferation of germ cells and resumption of normal eye development, suggesting that the phenotypes induced by nsPEF are caused by a decrease of retinoic acid levels. These results confirm that nsPEFs induce novel effects during embryogenesis in medaka.

  11. Genetic Diversity in Haploid Nicotiana alata Induced by Gamma Irradiation, Salt Tolerance and Detection of These Differences by RAPD

    Directory of Open Access Journals (Sweden)

    Ayman EL-FIKI

    2016-03-01

    Full Text Available Haploid plants of Nicotiana alata were cultured in vitro on MS medium with IAA + KIN. The resulting plantlets were irradiated using gamma radiation doses of 10, 15, 20 and 25 Gy. Single node pieces were cut and transferred onto fresh MS medium. Gamma radiation doses caused the death of 9% and up to 28% of explants. NaCl concentrations caused the death of 8% up to 36% of explants, while the combined effect between gamma radiation doses and salinity had an impact suffused on the percentage of survival. The combined effect of gamma radiation doses 20 Gy and 25 Gy on NaCl concentrations of 100, 150 and 200 mM were deadly. Even more, the combined effect of gamma radiation doses and salinity had a severe negative impact on both the proline content and total soluble protein. Random amplified polymorphic DNA (RAPD analysis was used to determine the degree of genetic variation in treated haploid Nicotiana alata plants. Total genomic DNAs from different haploid plantlets treated were amplified using five arbitrary primers. Two hundred and seventy bands were detected from plantlets irradiated with doses of 15, 20 and 25 Gy, with polymorphic band number 226 (83.7%. The total number of bands resulted from plant grew on 150 mM and 200 mM NaCl were 260 bands with polymorphic bands 185 (85.6%. However, the total number of bands produced from combined effects between gamma rays and salinity (20 Gy X 50 mM NaCl, 20 Gy X 100 mM NaCl and 25 Gy X 50 mM NaCl were 270, with polymorphic band number 231 (85.5%. High similarity between treatments was revealed. Treatments relationships were estimated through cluster analysis (UPGMA based on RAPD data.

  12. Evaluation of the effects of ethinylestradiol on sexual differentiation in the olvas-GFP/STII-YI medaka (transgenic Oryzias latipes) strain as estimated by proliferative activity of germ cells

    International Nuclear Information System (INIS)

    Hano, Takeshi; Oshima, Yuji; Kinoshita, Masato; Tanaka, Minoru; Mishima, Noriko; Wakamatsu, Yuko; Ozato, Kenjiro; Shimasaki, Yohei; Honjo, Tsuneo

    2011-01-01

    We evaluated the effects of 17(-ethinylestradiol (EE 2 ) on sexual differentiation in transgenic olvas-GFP/STII-YI medaka (Oryzias latipes) in terms of the proliferative activity of germ cells. This strain contains the green fluorescent protein (GFP) gene fused to the regulatory region of the medaka vasa gene, and germ cell-specific expression of GFP can be visualized in living (transparent) individuals. From 0 days post-hatch (0 dph) onwards, juveniles were exposed to graded concentrations of EE 2 (25.2-1710 ng/L) for 35 days. The gonads of live specimens were monitored by measuring their size and calculating their GFP-fluorescence area. GFP-fluorescent area in control females was about 10 times that in control males at 10 days posthatch (dph) whereas the gonadal size of 10 dph males that had been exposed to 158 ng/L of EE 2 significantly increased up to twice the size of control males, indicating that abnormal sexual differentiation towards female might occur in these individuals. Histological examination and identification of the sex-linked marker SL1 indicated that male to female sex reversal occurred at EE 2 exposure ≥45.1 ng/L at 35 dph. These results suggest that observation of proliferative activity of germ cells in the olvas-GFP/STII-YI strain could be applied to facilitated screening fish model to detect adverse effects on sexual differentiation as early as 10 dph juveniles.

  13. DNA repair studies in mouse germ cells exposed to two carcinogens and two non-carcinogens

    International Nuclear Information System (INIS)

    Sega, G.A.; Owens, J.G.

    1987-01-01

    An in vivo test was used to measure induced unscheduled DNA synthesis (UDS) in the germ cells of male mice exposed to the carcinogens benzo(a)pyrene [B(a)P] and 2-acetylaminofluorene (2AAF), and to the noncarcinogens pyrene (PYR) and 4-acetylaminofluorene (4AAF). Early spermatids, a DNA-repair competent stage, were used to test the effects of all chemicals. After chemical treatment and testicular injection of [ 3 H]dThd, sperm were recovered 16 days later from the caudal epididymides (these sperm were in early spermatid stages at the time of treatment) and assayed for the unscheduled incorporation of [ 3 H]dThd using liquid scintillation counting (LSC). Exposures of 2AAF ranged from 125 to 1600 mg/kg, 4AAF from 125 to 2000 mg/kg, PYR from 100 to 600 mg/kg, B(a)P from 100 to 400 mg/kg. Chemicals were administered both by intraperitoneal (i.p.) injection and by gavage. Methyl methanesulfonate (MMS) was used as a positive control

  14. Noninvasive Prenatal Diagnosis of Hypohidrotic Ectodermal Dysplasia by Tooth Germ Sonography.

    Science.gov (United States)

    Wünsche, S; Jüngert, J; Faschingbauer, F; Mommsen, H; Goecke, T; Schwanitz, K; Stepan, H; Schneider, H

    2015-08-01

    Hypohidrotic ectodermal dysplasia, a potentially life-threatening heritable disorder, may be recognized already in utero by characteristic features such as oligodontia and mandibular hypoplasia. As therapeutic options and prognosis depend on the time point of diagnosis, early recognition was attempted during routine prenatal ultrasound examinations. Fetuses of nine pregnant women (one triplet and eight singleton pregnancies) with family histories of hypohidrotic ectodermal dysplasia were investigated by sonography between the 20th and 24th week of gestation. In 4 male and 2 female fetuses reduced amounts of tooth germs were detected, whereas 5 fetal subjects showed the normal amount. Three-dimensional ultrasound evaluation revealed mandibular hypoplasia in 5 of the 6 fetuses with oligodontia. Molecular genetic analysis and/or clinical findings after birth confirmed the prenatal sonographic diagnosis in each subject. In subjects with a family history of hypohidrotic ectodermal dysplasia, the diagnosis of this rare condition can be established noninvasively by sonography in the second trimester of pregnancy. Early recognition of the disorder may help to prevent dangerous hyperthermic episodes in infancy and may allow timely therapeutic interventions. © Georg Thieme Verlag KG Stuttgart · New York.

  15. Clinical profile, treatment and survival outcomes of peadiatric germ cell tumours: A Pakistani perspective.

    Science.gov (United States)

    Islam Nasir, Irfan Ul; Ashraf, Muhammad Ijaz; Ahmed, Nouman; Shah, Muhammad Fahd; Pirzada, Muhammad Taqi; Syed, Amir Ali; Qazi, Abid Quddus

    2016-10-01

    Germ Cell Tumours (GCTs) are rare tumours. Generally 80% are benign and 20% malignant with a bimodal age distribution. The retrospective study was conducted at Shaukat Khanum Cancer Hospital, Lahore, Pakistan, and comprised all paediatric patients below 18 years of age who received treatment for histology-proven GCT from 2006 to 2014. Of the 207 patients, 98(42.3%) were males and 109(52.7%) were females. The most common GCT was yolk sac tumour in 90(43.5%) children followed by mixed GCT in 40(19.3%) and dysgerminoma in 34(16.4%). Gonads were most commonly involved in 165(79.7%) patients with metastasis in 24(11.6%) at presentation and recurrence in 26(12.5%) patients. Overall, 133(64.3%) patients are well and followed up at regular intervals and 55(26.5%) have been lost to follow-up with an expected overall 5-year median survival of 45%. Despite the distinct clinical profile of paediatric GCT, survival can be improved by early diagnosis, regimented treatment according to set guidelines, protocols and by improving follow-up.

  16. Impact of Coagulase-Negative Staphylococci and Other Germs on Sperm Forms

    Directory of Open Access Journals (Sweden)

    Ricardo Lozano-Hernández

    2017-08-01

    Full Text Available Coagulase-negative Staphylococci (CoNS is part of the microbiota of the male genitourinary tract, sometimes it has been considered as possible pathogenic microorganism. In the 5th version of sperm manual (WHO, 2010 sperm morphology criterion is very restricted to 4% of normal heads whereas David’s criterion evaluates several spermatic forms. The abnormalities of sperm forms were evaluated according to criteria of spermatic morphology: WHO and David in semen samples with bacterial concentrations ≤ 103, 104 and ≥ 105 CFU/mL of CoNS as of other bacteria. Spermogram, sperm culture and antibodies anti-Chlamydia trachomatis IgA detection in 281 semen samples men were performed. CoNS was the most frequent germ isolated in pure culture (9.25%. Semen samples with CoNS showed higher round cells and microcephalus forms by means of David’s criterion. CoNS in higher concentrations than 104 CFU/mL may have a negative impact on sperm cellularity, sperm head and probably on fertility.

  17. Conservation of Poultry Germplasm Through Cryopreservation of Primordial Germ Cells (PGCs

    Directory of Open Access Journals (Sweden)

    A R Setioko

    2008-06-01

    Full Text Available Indonesia has abundantly available genetic potential of local poultry that needs to be conserved for future use of poultry development. Live conservation of poultry, both in-situ and ex-situ, would be very expensive and has a risk of mortality due to diseases such as avian influenza. Cryopreservation of Primordial Germ Cells (PGCs, which are progenitor of eggs and spermatozoa, provides an alternative way to preserve both male and female genetic materials in poultry. PGCs in poultry can be specifically harvested from blatoderm or blood embryo, and preserved in a liquid nitrogen similar to sperm, ovum and embryo in large ruminant. Technique for producing germline chimeric chicken has been established by transferring PGCs into the circulated blood embryo where the original PGCs have been removed or inactivated. Mating of germline chimeras yields offsprings that are derived entirely from the donor stock. Conservation of genetic materials of Indonesian indigenous poultry through preservation of PGCs could be used for future poultry improvement.

  18. Evaluation of corn germ from ethanol production as an alternative fat source in dairy cow diets.

    Science.gov (United States)

    Abdelqader, M M; Hippen, A R; Kalscheur, K F; Schingoethe, D J; Karges, K; Gibson, M L

    2009-03-01

    Sixteen multiparous cows (12 Holstein and 4 Brown Swiss, 132 +/- 20 d in milk) were used in a replicated 4 x 4 Latin square design with 4-wk periods to determine the effects of feeding corn germ on dairy cow performance. Diets were formulated with increasing concentrations of corn germ (Dakota Germ, Poet Nutrition, Sioux Falls, SD) at 0, 7, 14, and 21% of the diet dry matter (DM). All diets had a 55:45 forage to concentrate ratio, where forage was 55% corn silage and 45% alfalfa hay. Dietary fat increased from 4.8% in the control diet to 8.2% at the greatest inclusion level of corn germ. The addition of corn germ resulted in a quadratic response in DM intake with numerically greater intake at 14% of diet DM. Feeding corn germ at 7 and 14% of diet DM increased milk yield and energy-corrected milk as well as fat percentage and yield. Milk protein yield tended to decrease as the concentration of corn germ increased in the diet. Dietary treatments had no effect on feed efficiency, which averaged 1.40 kg of energy-corrected milk/kg of DMI. Increasing the dietary concentration of corn germ resulted in a linear increase in milk fat concentrations of monounsaturated and polyunsaturated fatty acids at the expense of saturated fatty acids. Milk fat concentration and yield of cis-9, trans-11 and trans-10, cis-12 conjugated linoleic acid were increased with increased dietary concentrations of corn germ. Although milk fat concentrations of both total trans-18:1 and cis-18:1 fatty acids increased linearly, a marked numeric increase in the concentration of trans-10 C18:1 was observed in milk from cows fed the 21% corn germ diet. A similar response was observed in plasma concentration of trans-10 C18:1. Feeding increasing concentrations of corn germ had no effect on plasma concentrations of glucose, triglyceride, or beta-hydroxybutyrate; however, the concentration of nonesterified fatty acids increased linearly, with plasma cholesterol concentration demonstrating a similar trend

  19. Pathobiology of germ cell tumors - applying the gossip test!

    Science.gov (United States)

    Looijenga, Leendert H J; Oosterhuis, J Wolter

    2013-01-01

    Residual mature teratoma, a frequent finding in clinical pathology since the introduction of cisplatin-based chemotherapy, put Wolter Oosterhuis on the track of germ cell tumors (GCTs). These neoplasms in the borderland between developmental biology and oncology have fascinated him ever since. He tells the story on how GCTs brought him in contact with leading investigators in the field like Ivan Damjanov, Peter Andrews, and Niels Skakkebaek. His fruitful line of research was made possible through a longstanding collaboration with Bauke de Jong and, to this day, Leendert Looijenga who joined his group as a student in 1988. Probably their most important contribution to the field of GCTs is an integrated approach to GCTs, combining epidemiology, pathology, (cyto)genetics and molecular biology, that has resulted in a pathobiology-based classification of GCTs in five types. It has clinical relevance and stimulates further research on these intriguing neoplasms and their corresponding animal models.

  20. Functional fixation of autotransplanted tooth germs by using bioresorbable membranes.

    Science.gov (United States)

    Gérard, Eric; Membre, Hervé; Gaudy, Jean-François; Mahler, Patrick; Bravetti, Pierre

    2002-12-01

    The purpose of this study was to evaluate the contribution of a bioresorbable membrane placement to the healing of immature teeth after autotransplantation of tooth buds. Six cases were selected: 2 transplantations of wisdom teeth, 2 for premolar agenesis, 1 for ectopia, and 1 premolar in an incisor position. The crown of each tooth germ and the marginal alveolar bone were covered with a resorbable membrane. The radicular edification was nearly complete, neither ankylosis nor inflammatory resorption was observable, the pulp vitality was preserved, and the periodontal integration was identical to that of other teeth. The membrane ensured contention and stabilization of the transplant, allowed functional stimulation, permitted protection of the coagulum and periodontal cells, and kept the epithelium at a distance. The transplantations of immature teeth were improved by the use of a resorbable membrane, which caused an optimal functional fixation of the transplanted tooth.

  1. Testicular germ cell tumours and parental occupational exposure to pesticides

    DEFF Research Database (Denmark)

    Le Cornet, Charlotte; Fervers, Béatrice; Oksbjerg Dalton, Susanne

    2015-01-01

    OBJECTIVES: A potential impact of exposure to endocrine disruptors, including pesticides, during intrauterine life, has been hypothesised in testicular germ cell tumour (TGCT) aetiology, but exposure assessment is challenging. This large-scale registry-based case-control study aimed to investigate...... controls per case were randomly selected from the general national populations, matched on year of birth. Information on parental occupation was collected through censuses or Pension Fund information and converted into a pesticide exposure index based on the Finnish National Job-Exposure Matrix. RESULTS......: A total of 9569 cases and 32 028 controls were included. No overall associations were found for either maternal or paternal exposures and TGCT risk in their sons, with ORs of 0.83 (95% CI 0.56 to 1.23) and of 1.03 (0.92 to 1.14), respectively. Country-specific estimates and stratification by birth cohorts...

  2. Segregation distortion in homozygous lines obtained via anther culture and maize doubled haploid methods in comparison to single seed descent in wheat (Triticum aestivum L.

    Directory of Open Access Journals (Sweden)

    Tadeusz Adamski

    2014-01-01

    Conclusions: Segregation distortion in DH-AC populations was caused by the development of more than one plant of the same genotype from one callus. This distortion was minimized if only one plant per callus was included in the population. Selection of haploid wheat plants before chromosome doubling based on allele-specific markers allows us to choose genotypes that possess desirable Glu-1 alleles and to reduce the number of plants in the next steps of DH production. The SSD technique appeared to be the most advantageous in terms of Mendelian segregation, thus the occurrence of residual heterozygosity can be minimized by continuous selfing beyond the F6 generation.

  3. Induction and persistence of abnormal testicular germ cells following gestational exposure to di-(n-butyl) phthalate in p53-null mice.

    Science.gov (United States)

    Saffarini, Camelia M; Heger, Nicholas E; Yamasaki, Hideki; Liu, Tao; Hall, Susan J; Boekelheide, Kim

    2012-01-01

    Phthalate esters are commonly used plasticizers found in many household items, personal care products, and medical devices. Animal studies have shown that in utero exposure to di-(n-butyl) phthalate (DBP) within a critical window during gestation causes male reproductive tract abnormalities resembling testicular dysgenesis syndrome. Our studies utilized p53-deficient mice for their ability to display greater resistance to apoptosis during development. This model was chosen to determine whether multinucleated germ cells (MNG) induced by gestational DBP exposure could survive postnatally and evolve into testicular germ cell cancer. Pregnant dams were exposed to DBP (500 mg/kg/day) by oral gavage from gestational day 12 until birth. Perinatal effects were assessed on gestational day 19 and postnatal days 1, 4, 7, and 10 for the number of MNGs present in control and DBP-treated p53-heterozygous and null animals. As expected, DBP exposure induced MNGs, with greater numbers found in p53-null mice. Additionally, there was a time-dependent decrease in the incidence of MNGs during the early postnatal period. Histologic examination of adult mice exposed in utero to DBP revealed persistence of abnormal germ cells only in DBP-treated p53-null mice, not in p53-heterozygous or wild-type mice. Immunohistochemical staining of perinatal MNGs and adult abnormal germ cells was negative for both octamer-binding protein 3/4 and placental alkaline phosphatase. This unique model identified a role for p53 in the perinatal apoptosis of DBP-induced MNGs and provided insight into the long-term effects of gestational DBP exposure within a p53-null environment.

  4. Overexpression of aromatase alone is sufficient for ovarian development in genetically male chicken embryos.

    Directory of Open Access Journals (Sweden)

    Luke S Lambeth

    Full Text Available Estrogens play a key role in sexual differentiation of both the gonads and external traits in birds. The production of estrogen occurs via a well-characterised steroidogenic pathway, which is a multi-step process involving several enzymes, including cytochrome P450 aromatase. In chicken embryos, the aromatase gene (CYP19A1 is expressed female-specifically from the time of gonadal sex differentiation. To further explore the role of aromatase in sex determination, we ectopically delivered this enzyme using the retroviral vector RCASBP in ovo. Aromatase overexpression in male chicken embryos induced gonadal sex-reversal characterised by an enlargement of the left gonad and development of ovarian structures such as a thickened outer cortex and medulla with lacunae. In addition, the expression of key male gonad developmental genes (DMRT1, SOX9 and Anti-Müllerian hormone (AMH was suppressed, and the distribution of germ cells in sex-reversed males followed the female pattern. The detection of SCP3 protein in late stage sex-reversed male embryonic gonads indicated that these genetically male germ cells had entered meiosis, a process that normally only occurs in female embryonic germ cells. This work shows for the first time that the addition of aromatase into a developing male embryo is sufficient to direct ovarian development, suggesting that male gonads have the complete capacity to develop as ovaries if provided with aromatase.

  5. A Case of Nongerminomatous Germ Cell Tumor of the Pineal Region: Risks and Advantages of Biopsy by Endoscopic Approach.

    Science.gov (United States)

    Dobran, Mauro; Nasi, Davide; Mancini, Fabrizio; Gladi, Maurizio; Scerrati, Massimo

    2018-01-01

    A 21-year-old male was admitted to our department with headache and drowsiness. CT scan and MRI revealed acute obstructive hydrocephalus caused by a pineal region mass. The serum and CSF levels of beta-human chorionic gonadotropin (beta-hCG) were 215 IU/L and 447 IU/L, respectively, while levels of alpha-fetoprotein (AFP) were normal. A germ cell tumor (GCT) was suspected, and the patient underwent endoscopic third ventriculostomy (ETV) with biopsy. After four days from surgery, the tumor bled with mass expansion and ETV stoma occlusion; thus, a ventriculoperitoneal shunt was positioned. After ten months, the tumor metastasized to the thorax and abdomen with progression of intracerebral tumor mass. Despite the aggressive nature of this tumor, ETV remains a valid approach for a pineal region mass, but in case of GCT, the risk of bleeding should be taken into account, during and after the surgical procedure.

  6. A Case of Nongerminomatous Germ Cell Tumor of the Pineal Region: Risks and Advantages of Biopsy by Endoscopic Approach

    Directory of Open Access Journals (Sweden)

    Mauro Dobran

    2018-01-01

    Full Text Available A 21-year-old male was admitted to our department with headache and drowsiness. CT scan and MRI revealed acute obstructive hydrocephalus caused by a pineal region mass. The serum and CSF levels of beta-human chorionic gonadotropin (beta-hCG were 215 IU/L and 447 IU/L, respectively, while levels of alpha-fetoprotein (AFP were normal. A germ cell tumor (GCT was suspected, and the patient underwent endoscopic third ventriculostomy (ETV with biopsy. After four days from surgery, the tumor bled with mass expansion and ETV stoma occlusion; thus, a ventriculoperitoneal shunt was positioned. After ten months, the tumor metastasized to the thorax and abdomen with progression of intracerebral tumor mass. Despite the aggressive nature of this tumor, ETV remains a valid approach for a pineal region mass, but in case of GCT, the risk of bleeding should be taken into account, during and after the surgical procedure.

  7. Quantitative radiobiology: a method of in vivo study of germ cells exposed to gamma and neutron radiation, descriptive models

    International Nuclear Information System (INIS)

    Lemaire, Guy.

    1977-01-01

    A technique of quantitative analysis of in vivo cell survival of the germ cells of male rats was developed from the gonadal weight loss observed after irradiation. This technique - both global and functional - of quantifiying a cellular damage has several advantages: cell survival is completely studied in vivo; the dose range investigated is large; the results can be extended to man. The cell survival after γ and neutron exposure thus determined was investigated in the light of four cell survival theories: LEA's target theory; KELLERER and ROSSI's theory of dual action, CHADWICKS and LEENHOUT's molecular theory, and DELATTRE's general theory of transformation systems. The experimental results were well described by each theory. It was therefore concluded that the fundamental oneness of these theories should make it possible to include them all in a strict conceptual frame [fr

  8. A correlative study on the frequencies of radiation-induced chromosome aberrations in somatic and germ cells of mammals

    International Nuclear Information System (INIS)

    Buul, P.P.W. van

    1976-01-01

    A series of investigations on the correlation between the frequencies of radiation-induced chromosome aberrations in somatic and germ cells of mouse and rhesus monkey is described. In the mouse the induction of reciprocal translocations in bone-marrow cells was compared with that in spermatogonia (as scored in the descending spermatocytes). In the rhesus monkey frequencies of radiation-induced chromosome aberrations in spermatogonia and peripheral blood lymphocytes were studied. Furthermore the effect of multigeneration irradiation (69 generations with 200 rads X-rays) on the sensitivity for translocation induction in spermatogonia of male mice was studied. Frequencies of dicentric chromosomes and chromosomal deletions in cultured peripheral blood lymphocytes of 5 different types of mice were determined following in vitro irradiation with doses of 100 and/or 200 rad X-rays. To obtain more insight into the processes underlying translocation induction in spermatogonia of the mouse, fractionation experiments were conducted

  9. In utero exposure to nanosized carbon black (Printex90) does not induce tandem repeat mutations in female murine germ cells

    DEFF Research Database (Denmark)

    Boisen, Anne Mette Zenner; Shipley, Thomas; Jackson, Petra

    2013-01-01

    Inhalation of particles has been shown to induce mutations in the male germline in mice following both prenatal and adult exposures in several experiments. In contrast, the effects of particles on female germ cell mutagenesis are not well established. Germline mutations are induced during active...... cell division, which occurs during fetal development in females. We investigated the effects of prenatal exposure to carbon black nanoparticles (CB) on induction of mutations in the female mouse germline during fetal development, spanning the critical developmental stages of oogenesis. Pregnant C57BL/6...... mutation rates in the resulting F2 generation were determined from full pedigrees (mother, father, offspring) of F1 female mice (178 CB-exposed and 258 control F2 offspring). ESTR mutation rates in CB-exposed F2 female offspring were not statistically different from those of F2 female control offspring....

  10. Germ Cell Proteins in Melanoma: Prognosis, Diagnosis, Treatment, and Theories on Expression

    International Nuclear Information System (INIS)

    Rosa, A. M.; Dabas, N.; Byrnes, D. M.; Eller, M. S.; Grichnik, J. M.; Grichnik, J M.; Grichnik, J M.

    2012-01-01

    Germ cell protein expression in melanoma has been shown to correlate with malignancy, severity of disease and to serve as an immunologic target for therapy. However, very little is known about the role that germ cell proteins play in cancer development. Unique germ cell pathways include those involved in immortalization, genetic evolution, and energy metabolism. There is an ever increasing recognition that within tumors there is a subpopulation of cells with stem-cell-like characteristics that play a role in driving tumor genesis. Stem cell and germ cell biology is intertwined. Given the enormous potential and known expression of germ cell proteins in melanoma, it is possible that they represent a largely untapped resource that may play a fundamental role in tumor development and progression. The purpose of this paper is to provide an update on the current value of germ cell protein expression in melanoma diagnosis, prognosis, and therapy, as well as to review critical germ cell pathways and discuss the potential roles these pathways may play in malignant transformation

  11. Generation of organized germ layers from a single mouse embryonic stem cell.

    Science.gov (United States)

    Poh, Yeh-Chuin; Chen, Junwei; Hong, Ying; Yi, Haiying; Zhang, Shuang; Chen, Junjian; Wu, Douglas C; Wang, Lili; Jia, Qiong; Singh, Rishi; Yao, Wenting; Tan, Youhua; Tajik, Arash; Tanaka, Tetsuya S; Wang, Ning

    2014-05-30

    Mammalian inner cell mass cells undergo lineage-specific differentiation into germ layers of endoderm, mesoderm and ectoderm during gastrulation. It has been a long-standing challenge in developmental biology to replicate these organized germ layer patterns in culture. Here we present a method of generating organized germ layers from a single mouse embryonic stem cell cultured in a soft fibrin matrix. Spatial organization of germ layers is regulated by cortical tension of the colony, matrix dimensionality and softness, and cell-cell adhesion. Remarkably, anchorage of the embryoid colony from the 3D matrix to collagen-1-coated 2D substrates of ~1 kPa results in self-organization of all three germ layers: ectoderm on the outside layer, mesoderm in the middle and endoderm at the centre of the colony, reminiscent of generalized gastrulating chordate embryos. These results suggest that mechanical forces via cell-matrix and cell-cell interactions are crucial in spatial organization of germ layers during mammalian gastrulation. This new in vitro method could be used to gain insights on the mechanisms responsible for the regulation of germ layer formation.

  12. Control over the morphology and segregation of Zebrafish germ cell granules during embryonic development

    Directory of Open Access Journals (Sweden)

    Nakkrasae La-Iad

    2008-05-01

    Full Text Available Abstract Background Zebrafish germ cells contain granular-like structures, organized around the cell nucleus. These structures share common features with polar granules in Drosophila, germinal granules in Xenopus and chromatoid bodies in mice germ cells, such as the localization of the zebrafish Vasa, Piwi and Nanos proteins, among others. Little is known about the structure of these granules as well as their segregation in mitosis during early germ-cell development. Results Using transgenic fish expressing a fluorescently labeled novel component of Zebrafish germ cell granules termed Granulito, we followed the morphology and distribution of the granules. We show that whereas these granules initially exhibit a wide size variation, by the end of the first day of development they become a homogeneous population of medium size granules. We investigated this resizing event and demonstrated the role of microtubules and the minus-end microtubule dependent motor protein Dynein in the process. Last, we show that the function of the germ cell granule resident protein the Tudor domain containing protein-7 (Tdrd7 is required for determination of granule morphology and number. Conclusion Our results suggest that Zebrafish germ cell granules undergo a transformation process, which involves germ cell specific proteins as well as the microtubular network.

  13. Radiation-induced germ-line mutations detected by a direct comparison of parents and children DNA sequences containing SNPs

    International Nuclear Information System (INIS)

    Morimyo, M.; Hongo, E.; Higashi, T.; Wu, J.; Matsumoto, I.; Okamoto, M.; Kawano, A.; Tsuji, S.

    2003-01-01

    Full text: Germ-line mutation is detected in mice but not in humans. To estimate genetic risk of humans, a new approach to extrapolate from animal data to humans or to directly detect radiation-induced mutations in man is expected. We have developed a new method to detect germ-line mutations by directly comparing DNA sequences of parents and children. The nucleotide sequences among mouse strains are almost identical except SNP markers that are detected at 1/1000 frequency. When gamma-irradiated male mice are mated with female mice, heterogeneous nucleotide sequences induced in children DNA are a candidate of mutation, whose assignment can be done by SNP analysis. This system can easily detect all types of mutations such as transition, transversion, frameshift and deletion induced by radiation and can be applied to humans having genetically heterogeneous nucleotide sequences and many SNP markers. C3H male mice of 8 weeks of gestation were irradiated with gamma rays of 3 and 1 Gy and after 3 weeks, they were mated with the same aged C57BL female mice. After 3 weeks breeding, DNA was extracted from parents and children mice. The nucleotide sequences of 150 STS markers containing 300-900 bp and SNPs of parents and children DNA were determined by a direct sequencing; amplification of STS markers by Taq DNA polymerase, purification of PCR products, and DNA sequencing with a dye-terminator method. At each radiation dose, a total amount of 5 Mb DNA sequences were examined to detect radiation-induced mutations. We could find 6 deletions in 3 Gy irradiated mice but not in 1 Gy and control mice. The mutation frequency was about 4.0 x 10 -7 /bp/ Gy or 1.6 x 10 -4 /locus/Gy, and suggested the non-linear increase of mutation rate with dose

  14. Predictors of viable germ cell tumor in postchemotherapeutic residual retroperitoneal masses

    Directory of Open Access Journals (Sweden)

    Khalid Al Othman

    2014-01-01

    Full Text Available Objective: The aim of this study was to identify predictors of viable germ cell tumor (GCT in postchemotherapeutic residual retroperitoneal masses. Materials and Methods: The pertinent clinical and pathologic data of 16 male patients who underwent postchemotherapeutic retroperitoneal lymph node dissection (PC-RPLND at King Faisal Specialist Hospital and Research Centre between 1994 and 2005 were reviewed retrospectively. It was found that all patients received cisplatin-based chemotherapy for advanced testicular GCT. Results: Out of the 16 male patients, 2 (13%, 8 (50%, and 6 (37% had viable GCT, fibrosis, and teratoma, respectively. Ten (10 of the patients with prechemotherapeutic S1 tumor markers did not have viable GCT, and two of the six patients who had prechemotherapeutic S2 tumor markers have viable GCT. All tumor marker levels normalized after chemotherapy even in patients with viable GCT. Four patients had vascular invasion without viable GCT. Furthermore, four patients had more than 60% embryonal elements in the original pathology, but only 1 had viable GCT at PC-RPLND. Four of the five patients with immature teratoma had teratoma at PC-RPLND but no viable GCT; however, out of the four patients with mature teratoma, one had viable GCT and two had teratoma at PC-RPLND. Of the two patients with viable GCT, one had 100% embryonal cancer in the original pathology, prechemotherapeutic S2 tumor markers, history of orchiopexy, and no vascular invasion; the other patient had yolk sac tumor with 25% embryonal elements and 40% teratoma in the original pathology, and prechemotherapeutic S2 tumor markers. Conclusion: None of the clinical or pathological parameters showed a strong correlation with the presence of viable GCT in PC-RPLND. However, patients with ≥S2 may be at higher risk to have viable GCT. Further studies are needed to clarify this.

  15. The proteasome inhibitor bortezomib induces testicular toxicity by upregulation of oxidative stress, AMP-activated protein kinase (AMPK) activation and deregulation of germ cell development in adult murine testis

    International Nuclear Information System (INIS)

    Li, Wei; Fu, Jianfang; Zhang, Shun; Zhao, Jie; Xie, Nianlin; Cai, Guoqing

    2015-01-01

    Understanding how chemotherapeutic agents mediate testicular toxicity is crucial in light of compelling evidence that male infertility, one of the severe late side effects of intensive cancer treatment, occurs more often than they are expected to. Previous study demonstrated that bortezomib (BTZ), a 26S proteasome inhibitor used to treat refractory multiple myeloma (MM), exerts deleterious impacts on spermatogenesis in pubertal mice via unknown mechanisms. Here, we showed that intermittent treatment with BTZ resulted in fertility impairment in adult mice, evidenced by testicular atrophy, desquamation of immature germ cells and reduced caudal sperm storage. These deleterious effects may originate from the elevated apoptosis in distinct germ cells during the acute phase and the subsequent disruption of Sertoli–germ cell anchoring junctions (AJs) during the late recovery. Mechanistically, balance between AMP-activated protein kinase (AMPK) activation and Akt/ERK pathway appeared to be indispensable for AJ integrity during the late testicular recovery. Of particular interest, the upregulated testicular apoptosis and the following disturbance of Sertoli–germ cell interaction may both stem from the excessive oxidative stress elicited by BTZ exposure. We also provided the in vitro evidence that AMPK-dependent mechanisms counteract follicle-stimulating hormone (FSH) proliferative effects in BTZ-exposed Sertoli cells. Collectively, BTZ appeared to efficiently prevent germ cells from normal development via multiple mechanisms in adult mice. Employment of antioxidants and/or AMPK inhibitor may represent an attractive strategy of fertility preservation in male MM patients exposed to conventional BTZ therapy and warrants further investigation. - Highlights: • Intermittent treatment with BTZ caused fertility impairment in adult mice. • BTZ treatment elicited apoptosis during early phase of testicular recovery. • Up-regulation of oxidative stress by BTZ treatment

  16. The proteasome inhibitor bortezomib induces testicular toxicity by upregulation of oxidative stress, AMP-activated protein kinase (AMPK) activation and deregulation of germ cell development in adult murine testis

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wei [Department of Human Anatomy, Histology and Embryology, Fourth Military Medical University, Xi' an 710032 (China); Fu, Jianfang [Department of Endocrinology, Xijing Hospital, Fourth Military Medical University, Xi' an 710032 (China); Zhang, Shun [Reproductive Medicine Center, Department of Gynecology and Obstetrics, Tangdu Hospital, Fourth Military Medical University, Xi' an 710038 (China); Zhao, Jie [Department of Human Anatomy, Histology and Embryology, Fourth Military Medical University, Xi' an 710032 (China); Xie, Nianlin, E-mail: xienianlin@126.com [Department of Thoracic Surgery, Tangdu Hospital, Fourth Military Medical University, Xi' an 710038 (China); Cai, Guoqing, E-mail: firstchair@fmmu.edu.cn [Department of Gynaecology and Obstetrics, Xijing Hospital, Fourth Military Medical University, Xi' an 710032 (China)

    2015-06-01

    Understanding how chemotherapeutic agents mediate testicular toxicity is crucial in light of compelling evidence that male infertility, one of the severe late side effects of intensive cancer treatment, occurs more often than they are expected to. Previous study demonstrated that bortezomib (BTZ), a 26S proteasome inhibitor used to treat refractory multiple myeloma (MM), exerts deleterious impacts on spermatogenesis in pubertal mice via unknown mechanisms. Here, we showed that intermittent treatment with BTZ resulted in fertility impairment in adult mice, evidenced by testicular atrophy, desquamation of immature germ cells and reduced caudal sperm storage. These deleterious effects may originate from the elevated apoptosis in distinct germ cells during the acute phase and the subsequent disruption of Sertoli–germ cell anchoring junctions (AJs) during the late recovery. Mechanistically, balance between AMP-activated protein kinase (AMPK) activation and Akt/ERK pathway appeared to be indispensable for AJ integrity during the late testicular recovery. Of particular interest, the upregulated testicular apoptosis and the following disturbance of Sertoli–germ cell interaction may both stem from the excessive oxidative stress elicited by BTZ exposure. We also provided the in vitro evidence that AMPK-dependent mechanisms counteract follicle-stimulating hormone (FSH) proliferative effects in BTZ-exposed Sertoli cells. Collectively, BTZ appeared to efficiently prevent germ cells from normal development via multiple mechanisms in adult mice. Employment of antioxidants and/or AMPK inhibitor may represent an attractive strategy of fertility preservation in male MM patients exposed to conventional BTZ therapy and warrants further investigation. - Highlights: • Intermittent treatment with BTZ caused fertility impairment in adult mice. • BTZ treatment elicited apoptosis during early phase of testicular recovery. • Up-regulation of oxidative stress by BTZ treatment

  17. Recurrent population improvement of rice breeding facilitated with male sterility

    International Nuclear Information System (INIS)

    Fujimaki, Hiroshi

    1982-01-01

    A new rice breeding system has been developed, making use of genic male sterility to utilize diverse breeding materials and to promote genetic recombination. In this system, recurrent selection technique and introgressive hybridization were used to increase the frequencies of producing desired genotypes and to improve the population in succession. To promote genetic recombination by the recurrent selection technique, intermating within the population is necessary, and to introduce useful germ plasms by the introgressive hybridization, back crossing with new genetic material is necessary. These can be done efficiently by using the recessive alleles for male sterility, and the representative models for thisF type of breeding were presented. (Kaihara, S.)

  18. EKSTRAKSI DAN ANALISIS FITOSTEROL LEMBAGA GANDUM [Extraction and analysis of Phytosterol from wheat germ (Triticum sp.

    Directory of Open Access Journals (Sweden)

    Latifah K Darusman3

    2005-04-01

    Full Text Available Phytosterol may reduce the absorption of cholesterol, and used for preventing atherosclerosis. It is limited in soybean, but potentially abundant in wheat germ. Research on the utilization of wheat germ sterol had not been reported so far. Many aspects of germ sterol extraction from wheat germ and its characteristics were still unknown. In this research, the best extraction method, kinds and content of phytosterol from wheat germ were investigated.This research consisted of two steps: (1 extraction of phytosterol directly form whole germ and ground germ using hexane, and indirect extraction through germ oil using hexane and mixed solvent of hexane and ethanol, and direct extraction from ground germ using ethanol; (2 analysis of the type and content of phytosterol in the crude extract through the following steps: preparation of crude extract, fractionation, and analysis.Results showed that indirect extraction through germ oil was considered as the best method which yielded 1.37% of phytosterol. The highest yield was obtained when extracted using a mixed solvent of hexane – ethanol 82:18. However, the odor of ethanol and hexane (gasoline like odor was still detected. The solvent’s ratio of hexane to ethanol at 1:2 resulted better odor of the extract. Extraction of sterol using ethanol yielded 18.39% of sterol when the ratio of germ to ethanol at 1:10 (w/v was applied.Results of quantitative analysis on the main component of crude extract of wheat germ sterol showed that the total content of sterol extracted with mixed solvent was higher than those extracted with ethanol. The ratio of hexane to ethanol at 1:1 (v/v gave higher content of total sterol, stigmasterol and campesterol, whereas higher content of -sitosterol was produced at the solvent’s ratio of hexane to ethanol at 1:2 (v/v.

  19. Fat absorption in germ-free and conventional rats artificially deprived of bile secretion

    OpenAIRE

    Demarne, Y.; Corring, T.; Pihet, A.; Sacquet, E.

    1982-01-01

    Bile duct ligation was performed in germ-free and conventional rats in order to study the effects of bile deprivation on the absorption of dietary lipids and the excretion of faecal lipids in the presence or the absence of gastrointestinal flora. The main consequence of bile duct ligation in conventional rats was decrease of about 50% in the apparent absorption of dietary lipids (peanut oil). In germ-free rats, absorption decreased by only about 25%.In conventional as well as in germ-free con...

  20. Nanocarrier-mediated delivery of α-mangostin for non-surgical castration of male animals

    OpenAIRE

    Yostawonkul, Jakarwan; Surassmo, Suvimol; Namdee, Katawut; Khongkow, Mattaka; Boonthum, Chatwalee; Pagseesing, Sasithon; Saengkrit, Nattika; Ruktanonchai, Uracha Rungsardthong; Chatdarong, Kaywalee; Ponglowhapan, Suppawiwat; Yata, Teerapong

    2017-01-01

    The overpopulation of abandoned and stray companion animals has become a global crisis. The main purpose of this study was to develop a novel nanomedicine-based antifertility compound for non-surgical castration of male animals. Mangosteen (Garcinia mangostana L) pericarp extract has been shown to exhibit anti-fertility property. α-mangostin (AM)-loaded nanostructured lipid carrier (AM-NLC) was developed to improve male germ cell apoptosis. This study was conducted to investigate physicochemi...

  1. Defatted wheat germ application: Influence on cookies' properties with regard to its particle size and dough moisture content.

    Science.gov (United States)

    Petrović, Jovana; Rakić, Dušan; Fišteš, Aleksandar; Pajin, Biljana; Lončarević, Ivana; Tomović, Vladimir; Zarić, Danica

    2017-10-01

    The introduction of agro-food industry by-products rich in bioactive compounds represents major challenge in food industry sector. The influence of wheat germ particle size (Box-Behnken experimental design. The substitution of wheat flour with wheat germ increased the protein, fat, mineral, and fiber content of the cookies. The particle size of wheat germ affected the textural properties of cookies. As the particle size of wheat germ increased, the hardness of cookies decreased. The color of the cookie was most influenced by the interaction of dough moisture content and wheat germ particle size. Wheat germ level up to 15% had no significant effect on the sensory characteristics of cookies. A suitable combination of defatted wheat germ level, its particle size, and dough moisture content can improve the nutritional value of cookies, without causing a negative effect on the cookies' sensory characteristics.

  2. Comparison of Different Methods for Separation of Haploid Embryo Induced through Irradiated Pollen and Their Economic Analysis in Melon (Cucumis melo var. inodorus

    Directory of Open Access Journals (Sweden)

    Gökhan Baktemur

    2013-01-01

    Full Text Available Irradiated pollen technique is the most successful haploidization technique within Cucurbitaceae. After harvesting of fruits pollinated with irradiated pollen, classical method called as “inspecting the seeds one by one” is used to find haploid embryos in the seeds. In this study, different methods were used to extract the embryos more easily, quickly, economically, and effectively. “Inspecting the seeds one by one” was used as control treatment. Other four methods tested were “sowing seeds direct nutrient media,” “inspecting seeds in the light source,” “floating seeds on liquid media,” and “floating seeds on liquid media after surface sterilization.” Y2 and Y3 melon genotypes selected from the third backcross population of Yuva were used as plant material. Results of this study show that there is no statistically significant difference among methods “inspecting the seeds one by one,” “sowing seeds direct CP nutrient media,” and “inspecting seeds in the light source,” although the average number of embryos per fruit is slightly different. No embryo production was obtained from liquid culture because of infection. When considered together with labor costs and time required for embryo rescue, the best methods were “sowing seeds directly in the CP nutrient media“ and ”inspecting seeds in the light source.”

  3. Reduced Self-Diploidization and Improved Survival of Semi-cloned Mice Produced from Androgenetic Haploid Embryonic Stem Cells through Overexpression of Dnmt3b

    Directory of Open Access Journals (Sweden)

    Wenteng He

    2018-02-01

    Full Text Available Summary: Androgenetic haploid embryonic stem cells (AG-haESCs hold great promise for exploring gene functions and generating gene-edited semi-cloned (SC mice. However, the high incidence of self-diploidization and low efficiency of SC mouse production are major obstacles preventing widespread use of these cells. Moreover, although SC mice generation could be greatly improved by knocking out the differentially methylated regions of two imprinted genes, 50% of the SC mice did not survive into adulthood. Here, we found that the genome-wide DNA methylation level in AG-haESCs is extremely low. Subsequently, downregulation of both de novo methyltransferase Dnmt3b and other methylation-related genes was determined to be responsible for DNA hypomethylation. We further demonstrated that ectopic expression of Dnmt3b in AG-haESCs could effectively improve DNA methylation level, and the high incidence of self-diploidization could be markedly rescued. More importantly, the developmental potential of SC embryos was improved, and most SC mice could survive into adulthood. : Ectopic expression of Dnmt3b could rescue DNA methylation level in repetitive sequences of hypomethylated AG-haESCs, suppress high incidence of self-diploidization, and promote developmental potential of SC embryos, and most SC mice could survive into adulthood. Keywords: androgenetic haploid embryonic stem cells, self-diploidization, semi-cloned mice, DNA methylation, Dnmt3b

  4. Haploid genetic screens identify an essential role for PLP2 in the downregulation of novel plasma membrane targets by viral E3 ubiquitin ligases.

    Directory of Open Access Journals (Sweden)

    Richard T Timms

    Full Text Available The Kaposi's sarcoma-associated herpesvirus gene products K3 and K5 are viral ubiquitin E3 ligases which downregulate MHC-I and additional cell surface immunoreceptors. To identify novel cellular genes required for K5 function we performed a forward genetic screen in near-haploid human KBM7 cells. The screen identified proteolipid protein 2 (PLP2, a MARVEL domain protein of unknown function, as essential for K5 activity. Genetic loss of PLP2 traps the viral ligase in the endoplasmic reticulum, where it is unable to ubiquitinate and degrade its substrates. Subsequent analysis of the plasma membrane proteome of K5-expressing KBM7 cells in the presence and absence of PLP2 revealed a wide range of novel K5 targets, all of which required PLP2 for their K5-mediated downregulation. This work ascribes a critical function to PLP2 for viral ligase activity and underlines the power of non-lethal haploid genetic screens in human cells to identify the genes involved in pathogen manipulation of the host immune system.

  5. A Perfect Match Genomic Landscape Provides a Unified Framework for the Precise Detection of Variation in Natural and Synthetic Haploid Genomes.

    Science.gov (United States)

    Palacios-Flores, Kim; García-Sotelo, Jair; Castillo, Alejandra; Uribe, Carina; Aguilar, Luis; Morales, Lucía; Gómez-Romero, Laura; Reyes, José; Garciarubio, Alejandro; Boege, Margareta; Dávila, Guillermo

    2018-04-01

    We present a conceptually simple, sensitive, precise, and essentially nonstatistical solution for the analysis of genome variation in haploid organisms. The generation of a Perfect Match Genomic Landscape (PMGL), which computes intergenome identity with single nucleotide resolution, reveals signatures of variation wherever a query genome differs from a reference genome. Such signatures encode the precise location of different types of variants, including single nucleotide variants, deletions, insertions, and amplifications, effectively introducing the concept of a general signature of variation. The precise nature of variants is then resolved through the generation of targeted alignments between specific sets of sequence reads and known regions of the reference genome. Thus, the perfect match logic decouples the identification of the location of variants from the characterization of their nature, providing a unified framework for the detection of genome variation. We assessed the performance of the PMGL strategy via simulation experiments. We determined the variation profiles of natural genomes and of a synthetic chromosome, both in the context of haploid yeast strains. Our approach uncovered variants that have previously escaped detection. Moreover, our strategy is ideally suited for further refining high-quality reference genomes. The source codes for the automated PMGL pipeline have been deposited in a public repository. Copyright © 2018 by the Genetics Society of America.

  6. THE DEVELOPMENT OF SEXUAL DIMORPHISM: STUDIES OF THE C. ELEGANS MALE

    Science.gov (United States)

    Emmons, Scott W.

    2014-01-01

    Studies of the development of the C. elegans male have been carried out with the aim of understanding the basis of sexual dimorphism. Postembryonic development of the two C. elegans sexes differs extensively. Development along either the hermaphrodite or male pathway is specified initially by the X to autosome ratio. The regulatory events initiated by this ratio include a male-determining paracrine intercellular signal. Expression of this signal leads to different consequences in three regions of the body: the non-gonadal soma, the somatic parts of the gonad, and the germ line. In the non-gonadal soma, activity of the key Zn-finger transcription factor TRA 1 determines hermaphrodite development; in its absence, the male pathway is followed. Only a few genes directly regulated by TRA 1 are currently known, including members of the evolutionarily conserved, male-determining DM domain Zn-finger transcription factors. In the somatic parts of the gonad and germ line, absence of TRA 1 activity is not sufficient for full expression of the male pathway. Several additional transcription factors involved have been identified. In the germ line, regulatory genes for sperm development that act at the level of RNA in the cytoplasm play a prominent role. PMID:25262817

  7. Sex mosaics in a male dimorphic ant Cardiocondyla kagutsuchi

    Science.gov (United States)

    Yoshizawa, Juri; Mimori, Kohei; Yamauchi, Katsusuke; Tsuchida, Koji

    2009-01-01

    Gynandromorphy, or the development of organisms with a combination of male and female morphological features, is common in Hymenoptera. The underlying mechanism is likely associated with the sex-determination system, and studying this phenomenon should lead to a deeper understanding of both embryonic development and sex determination. The reproductive capabilities of gynandromorphs (hereafter, sex mosaics) remain unclear. We studied gynandromorphy in the Malaysian ant Cardiocondyla kagutsuchi, which has sex mosaics of queens (gynandromorphs; mosaic of queens and winged male) and workers (ergatandromorphs; mosaic of worker and wingless ergatoid male). These sex mosaics were classified into seven morphological categories. Most individuals had more male than female body areas. Behavioral observations revealed that sex mosaics behave more in accordance with the “sex” of their brain than that of the reproductive organs (gaster). Relative DNA quantities showed that both female and male regions contained haploid and diploid nuclei, irrespective of their phenotypic appearance, indicating that external appearance did not reflect internal tissues. Nearly one third of the adults were sex mosaics and they were not infected with Wolbachia. Our results suggest that the production of sex mosaics in this species does not pose a substantial cost to colonies and that the underlying causes are therefore not strongly selected against.

  8. Profiling of androgen response in rainbow trout pubertal testis: relevance to male gonad development and spermatogenesis.

    Directory of Open Access Journals (Sweden)

    Antoine D Rolland

    Full Text Available The capacity of testicular somatic cells to promote and sustain germ cell differentiation is largely regulated by sexual steroids and notably androgens. In fish species the importance of androgens is emphasized by their ability to induce sex reversal of the developing fries and to trigger spermatogenesis. Here we studied the influence of androgens on testicular gene expression in trout testis using microarrays. Following treatment of immature males with physiological doses of testosterone or 11-ketotestosterone, 418 genes that exhibit changes in expression were identified. Interestingly, the activity of testosterone appeared stronger than that of 11-ketotestosterone. Expression profiles of responsive genes throughout testis development and in isolated germ cells confirmed androgens to mainly affect gene expression in somatic cells. Furthermore, specific clusters of genes that exhibit regulation coincidently with changes in the natural circulating levels of androgens during the reproductive cycle were highlighted, reinforcing the physiological significance of these data. Among somatic genes, a phylogenetic footprinting study identified putative androgen response elements within the proximal promoter regions of 42 potential direct androgen target genes. Finally, androgens were also found to alter the germ line towards meiotic expression profiles, supporting the hypothesis of a role for the somatic responsive genes in driving germ cell fate. This study significantly increases our understanding of molecular pathways regulated by androgens in vertebrates. The highly cyclic testicular development in trout together with functions associated with regulated genes reveal potential mechanisms for androgen actions in tubule formation, steroid production, germ cell development and sperm secretion.

  9. Gonadal germ cell tumors in children and adolescents

    Directory of Open Access Journals (Sweden)

    Giovanni Cecchetto

    2014-01-01

    Full Text Available Pediatric germ cell tumors (GCT are rare tumors: 80% are benign, 20% malignant (2-3% of all malignant pediatric tumors. The gonadal sites (ovary and testis account for 40% of cases. Ovarian GCTs: Represent 30% of GCTs and 70% of neoplastic ovarian masses, being the most common ovarian neoplasms in children and teenagers. Benign and immature forms (teratomas constitute about 80% of all ovarian GCTs, malignant forms represent 20% increasing during adolescence. The most common malignant entity in children is the yolk sac tumors (YST; dysgerminoma is frequent during adolescence and being bilateral in 10% of cases. Presentation is similar in malignant and benign lesions; abdominal pain (70-80% and lower abdominal mass are common symptoms. Evaluation of alpha-fetoprotein (αFP or beta subunit of human chorionic gonadotropin (βHCG is essential to address the nature of the tumors: Their elevation means presence of malignancy. Surgery includes intraoperative staging procedures and requires ovariectomy or ovarosalpingectomy for malignant lesions, but may be conservative in selected benign tumors. Since malignant GCTs are very chemosensitive, primary chemotherapy is recommended in metastatic or locally advanced tumors. Testicular GCT: Represent 10% of pediatric GCT, and about 30% of malignant GCT with two age peaks: Children <3 years may experience mature teratoma and malignant GCTs, represented almost exclusively by YST, while adolescents may also show seminomas or other mixed tumors. The main clinical feature is a painless scrotal mass. Surgery represents the cornerstone of the management of testicular GCTs, with an inguinal approach and a primary high orchidectomy for malignant tumors, while a testis-sparing surgery can be considered for benign lesions. A retroperitoneal lymph node (LN biopsy may be necessary to define the staging when the involvement of retroperitoneal LN is uncertain at imaging investigations. Conclusion: Patients with gonadal

  10. Stereotactic radiotherapy for pediatric intracranial germ cell tumors

    International Nuclear Information System (INIS)

    Zissiadis, Yvonne; Dutton, Sharon; Kieran, Mark; Goumnerova, Liliana; Scott, R. Michael; Kooy, Hanne M.; Tarbell, Nancy J.

    2001-01-01

    Purpose: Intracranial germ cell tumors are rare, radiosensitive tumors seen most commonly in the second and third decades of life. Radiotherapy alone has been the primary treatment modality for germinomas, and is used with chemotherapy for nongerminomatous tumors. Stereotactic radiotherapy techniques minimize the volume of surrounding normal tissue irradiated and, hence, the late radiation morbidity. This study reports our experience with stereotactic radiotherapy in this group of tumors. Methods and Materials: Between December 1992 and December 1998, 18 patients with intracranial germ cell tumors were treated with stereotactic radiotherapy. A total of 23 histologically proven tumors were treated. Thirteen patients had a histologic diagnosis of germinoma, and 5 patients had germinoma with nongerminomatous elements. Of those patients with a histologic diagnosis of germinoma, 5 had multiple midline tumors. The median age of the patients was 12.9 years (range, 5.6-17.5 years). Results: A boost using stereotactic radiotherapy was delivered to 19 tumors following whole-brain radiation in 8 cases and craniospinal radiation in 11 cases. Three tumors were treated with stereotactic radiotherapy to the tumor volume alone following chemotherapy, and 1 tumor received a boost using stereotactic radiosurgery following craniospinal radiation. A median dose of 2520 cGy (range, 1500-3600) cGy was given to the whole brain, and a median dose of 2160 (range, 2100-2600) cGy was given to the spinal field. The median boost dose to the tumor was 2600 (range, 2160-3600) cGy, given by stereotactic radiotherapy delivered to the 95% isodose line. At a median follow-up time of 40 (range, 12-73) months, no local or marginal recurrences were reported in patients with germinoma. Two patients with nongerminomatous tumors have relapsed. One had elevation of tumor markers only at 37 months following treatment, and the other had persistent disease following chemotherapy and radiation therapy. Eight

  11. Pathogenesis of Testicular Germ Cell Tumors from a Developmental Point of View

    NARCIS (Netherlands)

    K. Biermann (Katharina)

    2010-01-01

    textabstractCurrent classification systems of human germ cell tumors (GCTs) are based on histological composition. In the group of nonseminomas, different variants of teratoma (somatic differentiation), yolk sac tumor and choriocarcinoma (extra-embryonic differentiation), are recognized, as well

  12. Expression of immunohistochemical markers for testicular carcinoma in situ by normal human fetal germ cells

    DEFF Research Database (Denmark)

    Jørgensen, N; Rajpert-De Meyts, E; Graem, N

    1995-01-01

    study. EXPERIMENTAL DESIGN: Normal human germ cells from 10 first-trimester fetuses and 76 second- and third-trimester testes were investigated for the immunohistochemical expression of the markers of testicular carcinoma in situ. The panel of markers included in the study consisted of placental......-like alkaline phosphatase, the protooncogene c-kit protein product, and the antigens for the monoclonal antibodies TRA-1-60 and M2A. The relative numbers of fetal germ cells that demonstrated positive reaction with the markers were calculated. RESULTS: The vast majority of the germ cells (75-100%) in the first......-trimester gonads were positive for placental-like alkaline phosphatase, TRA-1-60, and M2A. The c-kit protein was detected in three out of the ten first-trimester gonads. The relative number of germ cells positive for all the markers studied declined rapidly during the first part of the second trimester...

  13. In vivo cytogenetic effects of 2-trans hexenal on somatic and germ ...

    African Journals Online (AJOL)

    Francis

    meiotic cells. Wyrobek et al. (1983) emphasized that chemicals which are mutagenic to somatic cells, could also affect germ cells. The dose-dependent increase in the frequency of abnormal sperm observed in the present study suggests that ...

  14. Repair and mutation induction in mouse germ cells: a summary and some thoughts

    International Nuclear Information System (INIS)

    Russell, L.B.

    1979-01-01

    The various lines of evidence for repair of premutational damage in mouse germ cells are reviewed with the implications for future experiment planning. Relation between mutagenicity and carcinogenicity are discussed

  15. In Vitro Effect of Local Anesthetics on Candida albicans Germ Tube Formation

    Directory of Open Access Journals (Sweden)

    Acácio Rodrigues

    1994-01-01

    Full Text Available Objective: This study was planned to clarify the in vitro effect of lidocaine and bupivacaine on germ tube formation by Candida albicans isolates from cases of clinical vaginal candidiasis.

  16. The ethics of germ line gene manipulation--a five dimensional debate.

    Science.gov (United States)

    Carter, Lucy

    2002-10-01

    Contributors to the debate surrounding the ethics of germ line gene manipulation have by and large concentrated their efforts on discussions of the potential risks that are associated with the use of this technology. Many international advisory committees have ruled out the acceptability of germ line gene manipulation at least for the time being. The purpose of this work is to generate much needed discussion on the many other ethical issues concerning the implementation of not only germ line gene manipulation but also other related biotechnologies. In this paper I systematically investigate and analyse the most salient issues put forward by proponents and opponents alike. I argue that if germ line manipulation proves to be a safe and effective procedure, then the principle of beneficence imposes on the medical profession a moral duty to pursue the technology.

  17. Involvement of epigenetic modifiers in the pathogenesis of testicular dysgenesis and germ cell cancer

    DEFF Research Database (Denmark)

    Lawaetz, Andreas C.; Almstrup, Kristian

    2015-01-01

    Testicular germ cell cancer manifests mainly in young adults as a seminoma or non-seminoma. The solid tumors are preceded by the presence of a non-invasive precursor cell, the carcinoma in situ cell (CIS), which shows great similarity to fetal germ cells. It is therefore hypothesized that the CIS...... of epigenetic modifiers with a focus on jumonji C enzymes in the development of testicular dysgenesis and germ cell cancer in men....... cell is a fetal germ cell that has been arrested during development due to testicular dysgenesis. CIS cells retain a fetal and open chromatin structure, and recently several epigenetic modifiers have been suggested to be involved in testicular dysgenesis in mice. We here review the possible involvement...

  18. Analysis of Maize Seed Germs by Photoacoustic Microscopy and Photopyroelectric Technique

    Science.gov (United States)

    Pacheco, A. Domínguez; Aguilar, C. Hernández; Cruz-Orea, A.

    2013-05-01

    A knowledge about thermal parameters of structural components of maize seed is of great relevance in the seed technology practice. The objective of the present study was to determine the thermal effusivity of germs of maize ( Zea mays L.) of different genotypes by means of the photopyroelectric technique (PPE) in the inverse configuration and obtaining the thermal imaging of these samples by photoacoustic microscopy (PAM). Germs from crystalline maize (white pigment), semi-crystalline maize (yellow pigment), and floury maize (blue pigment) were used in this investigation. The results show differences between germs of maize seeds mainly in the values of their thermal effusivities. The thermal images showed minimum inhomogeneity of these seed germs. Characterizations of thermal parameters in seeds are important in agriculture and food production and could be particularly useful to define their quality and determine their utility. PPE and PAM can be considered as potential diagnostic tools for the characterization of agriculture seeds.

  19. The uranyl influence on a mutation process in germ and somatic cells of mice

    International Nuclear Information System (INIS)

    Kostrova, L.N.; Mosseh, I.B.; Molofej, V.P.

    2008-01-01

    The mutagenic effect of uranyl was revealed by the chromosome rearrangement test in germ and somatic cells of mice. The effect value depended on duration of substance administration into organism. (authors)

  20. Regulation of meiotic entry and gonadal sex differentiation in the human

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Rajpert-De Meyts, Ewa

    2014-01-01

    Meiosis is a unique type of cell division that is performed only by germ cells to form haploid gametes. The switch from mitosis to meiosis exhibits a distinct sex-specific difference in timing, with female germ cells entering meiosis during fetal development and male germ cells at puberty when...... spermatogenesis is initiated. During early fetal development, bipotential primordial germ cells migrate to the forming gonad where they remain sexually indifferent until the sex-specific differentiation of germ cells is initiated by cues from the somatic cells. This irreversible step in gonadal sex...... in the context of fetal gonad development and germ cell differentiation, with emphasis on results obtained in humans. Furthermore, the consequences of dysregulated meiosis signaling in humans are briefly discussed in the context of selected pathologies, including testicular germ cell cancer and some forms...