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

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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.

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.

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)

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.

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

Science.gov (United States)

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.

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

Science.gov (United States)

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.

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

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.

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)

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)

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.

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.

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).

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.

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

Science.gov (United States)

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

Genetic control of the development of the haploid generation in Oenothera

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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.

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.)

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

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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.

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

OpenAIRE

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...

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.

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.

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)

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)

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

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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.

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)

Lin28a regulates germ cell pool size and fertility

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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

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

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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.

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

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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.

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)

Fixation Probability in a Haploid-Diploid Population.

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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.

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

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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.

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

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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.

[Germ cell membrane lipids in spermatogenesis].

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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.

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.

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

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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.

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...

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

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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.

Production of haploids and doubled haploids in oil palm

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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.

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

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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.

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

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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.

Verification and characterization of chromosome duplication in haploid maize.

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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.

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

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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.

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.

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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.

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

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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.

Estrogens and male reproduction: a new concept

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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.

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

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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.

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

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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

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

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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.

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

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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.

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

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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.

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

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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.

Primary pleuro-pulmonary malignant germ cell tumours.

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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.

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

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

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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.

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)

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

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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...

Regulation of meiotic entry and gonadal sex differentiation in the human

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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...

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

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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.

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

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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.

Diploid male production in a leaf-cutting ant

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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...

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

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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.

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

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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

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.

On the development of extragonadal and gonadal human germ cells

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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.

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.

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...

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.

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.)

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

HP1γ function is required for male germ cell survival and spermatogenesis

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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.

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

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.

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

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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.

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

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

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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.

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.

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.

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

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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.

Two Y genes can replace the entire Y chromosome for assisted reproduction in the mouse.

Science.gov (United States)

Yamauchi, Yasuhiro; Riel, Jonathan M; Stoytcheva, Zoia; Ward, Monika A

2014-01-03

The Y chromosome is thought to be important for male reproduction. We have previously shown that, with the use of assisted reproduction, live offspring can be obtained from mice lacking the entire Y chromosome long arm. Here, we demonstrate that live mouse progeny can also be generated by using germ cells from males with the Y chromosome contribution limited to only two genes, the testis determinant factor Sry and the spermatogonial proliferation factor Eif2s3y. Sry is believed to function primarily in sex determination during fetal life. Eif2s3y may be the only Y chromosome gene required to drive mouse spermatogenesis, allowing formation of haploid germ cells that are functional in assisted reproduction. Our findings are relevant, but not directly translatable, to human male infertility cases.

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.

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.

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

DNMT3L is a regulator of X chromosome compaction and post-meiotic gene transcription.

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Natasha M Zamudio

Full Text Available Previous studies on the epigenetic regulator DNA methyltransferase 3-Like (DNMT3L, have demonstrated it is an essential regulator of paternal imprinting and early male meiosis. Dnmt3L is also a paternal effect gene, i.e., wild type offspring of heterozygous mutant sires display abnormal phenotypes suggesting the inheritance of aberrant epigenetic marks on the paternal chromosomes. In order to reveal the mechanisms underlying these paternal effects, we have assessed X chromosome meiotic compaction, XY chromosome aneuploidy rates and global transcription in meiotic and haploid germ cells from male mice heterozygous for Dnmt3L. XY bodies from Dnmt3L heterozygous males were significantly longer than those from wild types, and were associated with a three-fold increase in XY bearing sperm. Loss of a Dnmt3L allele resulted in deregulated expression of a large number of both X-linked and autosomal genes within meiotic cells, but more prominently in haploid germ cells. Data demonstrate that similar to embryonic stem cells, DNMT3L is involved in an auto-regulatory loop in germ cells wherein the loss of a Dnmt3L allele resulted in increased transcription from the remaining wild type allele. In contrast, however, within round spermatids, this auto-regulatory loop incorporated the alternative non-coding alternative transcripts. Consistent with the mRNA data, we have localized DNMT3L within spermatids and sperm and shown that the loss of a Dnmt3L allele results in a decreased DNMT3L content within sperm. These data demonstrate previously unrecognised roles for DNMT3L in late meiosis and in the transcriptional regulation of meiotic and post-meiotic germ cells. These data provide a potential mechanism for some cases of human Klinefelter's and Turner's syndromes.

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)

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.

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

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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

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

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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.

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.

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

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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.

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.

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

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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.

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

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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.

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...

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

Chemical reproductive traits of diploid Bombus terrestris males: Consequences on bumblebee conservation.

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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.

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

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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

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.

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

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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.

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

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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.

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

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

Testis-Specific Histone Variant H3t Gene Is Essential for Entry into Spermatogenesis

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Jun Ueda

2017-01-01

Full Text Available Cellular differentiation is associated with dynamic chromatin remodeling in establishing a cell-type-specific epigenomic landscape. Here, we find that mouse testis-specific and replication-dependent histone H3 variant H3t is essential for very early stages of spermatogenesis. H3t gene deficiency leads to azoospermia because of the loss of haploid germ cells. When differentiating spermatogonia emerge in normal spermatogenesis, H3t appears and replaces the canonical H3 proteins. Structural and biochemical analyses reveal that H3t-containing nucleosomes are more flexible than the canonical nucleosomes. Thus, by incorporating H3t into the genome during spermatogonial differentiation, male germ cells are able to enter meiosis and beyond.

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

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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.

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.)

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

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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.

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

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

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

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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.

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

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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

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

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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.

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

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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

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

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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.

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

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...

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

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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

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

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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.

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.

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

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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

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

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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

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

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

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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.

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

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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

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

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)

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

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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.

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...

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....

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

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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.

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)

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...

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

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.

Influence of time of auxin application on wheat haploid embrio formation

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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.

Biotechnological approaches to the treatment of aspermatogenic men

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Pedro Manuel Aponte

2013-01-01

Full Text Available Aspermatogenesis is a severe impairment of spermatogenesis in which germ cells are completely lacking or present in an immature form, which results in sterility in approximately 25% of patients. Because assisted reproduction techniques require mature germ cells, biotechnology is a valuable tool for rescuing fertility while maintaining biological fatherhood. However, this process involves, for instance, the differentiation of preexisting immature germ cells or the production/derivation of sperm from somatic cells. This review critically addresses four potential techniques: sperm derivation in vitro, germ stem cell transplantation, xenologous systems, and haploidization. Sperm derivation in vitro is already feasible in fish and mammals through organ culture or 3D systems, and it is very useful in conditions of germ cell arrest or in type II Sertoli-cell-only syndrome. Patients afflicted by type I Sertoli-cell-only syndrome could also benefit from gamete derivation from induced pluripotent stem cells of somatic origin, and human haploid-like cells have already been obtained by using this novel methodology. In the absence of alternative strategies to generate sperm in vitro, in germ cells transplantation fertility is restored by placing donor cells in the recipient germ-cell-free seminiferous epithelium, which has proven effective in conditions of spermatogonial arrest. Grafting also provides an approach for ex-vivo generation of mature sperm, particularly using prepubertal testis tissue. Although less feasible, haploidization is an option for creating gametes based on biological cloning technology. In conclusion, the aforementioned promising techniques remain largely experimental and still require extensive research, which should address, among other concerns, ethical and biosafety issues, such as gamete epigenetic status, ploidy, and chromatin integrity.

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...

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.

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

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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.

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

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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.

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.

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

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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.

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

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

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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.

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...

Transgenerational effect of the endocrine disruptor vinclozolin on male spermatogenesis.

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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

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)

Convergent evolution of germ granule nucleators: A hypothesis.

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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.

[Impact of zearalenone on male fertility: An update].

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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.

Extragonadal Germ Cell Cancer (EGC)

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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 ( ...

Hybrid male sterility is caused by mitochondrial DNA deletion.

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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.

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...

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

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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.

THE DEVELOPMENT OF SEXUAL DIMORPHISM: STUDIES OF THE C. ELEGANS MALE

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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

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....

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

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

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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

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...

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.

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

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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.

Foxn1[Cre] Expression in the Male Germline.

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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.

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

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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.

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

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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

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.

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

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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...

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

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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.

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

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)

Meiosis and haploid gametes in the pathogen Trypanosoma brucei.

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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.

Long term effects of ionizing radiation on mouse spermatogenesis

International Nuclear Information System (INIS)

Hacker-Klom, U.

1985-01-01

The effects of acute or split dose exposure to radiation on murine stem cell spermatogonia were analysed. Flow cytometry was applied to estimate the percentages of haploid germ cells (round and elongated spermatids) up to 12 months after irradiation. The recovery in the number of haploid germ cells continued gradually during the period under observation. The intervals between the two equal doses in split dose exposures were 0, 4, 8, 24 and 48 hours. Split doses that were 24 h or 48 h apart had more harmful effects on spermatogenesis than split doses with 4 or 8 hours intervals or acute exposures. The repair capacity of the stem cell spermatogonia was remarkably high. (orig.)

Segregation distortion causes large-scale differences between male and female genomes in hybrid ants.

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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.

Establishment of the Vertebrate Germ Layers.

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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.

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)

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

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

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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.

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

Understanding Mammalian Germ Line Development with In Vitro Models.

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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.

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

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...

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

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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.

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

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.

Germ Plasm Biogenesis--An Oskar-Centric Perspective.

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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.

Germ cell transplantation in an azoospermic Klinefelter bull.

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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.

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.

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.

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

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

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

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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

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)

Overexpression of aromatase alone is sufficient for ovarian development in genetically male chicken embryos.

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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.

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.

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

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

Successful fertilization and embryo development after spermatid injection: A hope for nonobstructive azoospermic patients

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Geeta Goswami

2015-01-01

Full Text Available Spermatids are the earliest male germ cells with haploid set of chromosomes. Spermatid injection was introduced in human assisted reproduction for the treatment of men with non-obstructive azoospermia. Spermatozoa can be recovered in half of patients with nonobstructive azoospermia. The use of spermatids for intracytoplasmic injection (ICSI has been proposed for cases in which no spermatozoa can be retrieved. However, there are low pregnancy rates following ICSI using round spermatids from men with no elongated spermatids or spermatozoa in their testes. The in vitroculture of immature germ cells has been proposed as a means to improve this poor outcome. Oocyte activation rarely occurs when injected with a spermatid. Therefore, spermatid injection requires use of calcium ionophores for oocyte activation which is otherwise carried out by PLC zeta from mature sperms. This is the only option available for the nonobstructive azoospermic patients to have their own biological child.

Testicular germ cell tumors: Molecular genetic and clinicomorphological aspects

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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. 

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

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

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.

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

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)

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.

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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

Wolbachia Protein TomO Targets nanos mRNA and Restores Germ Stem Cells in Drosophila Sex-lethal Mutants.

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Ote, Manabu; Ueyama, Morio; Yamamoto, Daisuke

2016-09-12

Wolbachia, endosymbiotic bacteria prevalent in invertebrates, manipulate their hosts in a variety of ways: they induce cytoplasmic incompatibility, male lethality, male-to-female transformation, and parthenogenesis. However, little is known about the molecular basis for host manipulation by these bacteria. In Drosophila melanogaster, Wolbachia infection makes otherwise sterile Sex-lethal (Sxl) mutant females capable of producing mature eggs. Through a functional genomic screen for Wolbachia genes with growth-inhibitory effects when expressed in cultured Drosophila cells, we identified the gene WD1278 encoding a novel protein we call toxic manipulator of oogenesis (TomO), which phenocopies some of the Wolbachia effects in Sxl mutant D. melanogaster females. We demonstrate that TomO enhances the maintenance of germ stem cells (GSCs) by elevating Nanos (Nos) expression via its interaction with nos mRNA, ultimately leading to the restoration of germ cell production in Sxl mutant females that are otherwise without GSCs. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

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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.

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.

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...

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 ...

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.

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....

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

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...

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).

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. ...

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.

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

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

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.

Sexual selection by male choice in monogamous and polygynous human populations.

Science.gov (United States)

Ihara, Y; Aoki, K

1999-02-01

The theoretical possibility of coevolution of a viability-reducing female physical trait and a male mating preference for that trait by Fisherian sexual selection in monogamous and polygynous populations is demonstrated using two-locus haploid models. It is assumed that there is dichotomous variation in male resources, resource-rich males have a wider choice among females than resource-poor males, and a female has greater reproductive success when mated with a resource-rich male than a resource-poor one. Under these assumptions, we find that sexual selection operates effectively when female reproductive success is strongly dependent on male resource, the proportion of females that mate with resource-rich males is neither small nor large, the degree of polygyny is low, and resources are inherited from father to son. We suggest that some human female physical traits may have evolved by sexual selection through male choice. The evolution of skin color by sexual selection is discussed as an example. Copyright 1999 Academic Press.

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...

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...

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

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

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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.

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...

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 ...

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.

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.

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 ...

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.

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

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

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...

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.)

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.

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.

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

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.

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.

Generation of doubled haploid transgenic wheat lines by microspore transformation.

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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.

ATTEMPT TO APPLY STABILIZED WHEAT GERM FOR BREAD SUPPLEMENTATION

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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.

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

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.

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.

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

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.

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%

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...

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)

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.

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.

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.

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

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.

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

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.

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

Assessing reproductive toxicity of two environmental toxicants with a novel in vitro human spermatogenic model

Directory of Open Access Journals (Sweden)

Charles A. Easley, IV

2015-05-01

Full Text Available Environmental influences and insults by reproductive toxicant exposure can lead to impaired spermatogenesis or infertility. Understanding how toxicants disrupt spermatogenesis is critical for determining how environmental factors contribute to impaired fertility. While current animal models are available, understanding of the reproductive toxic effects on human fertility requires a more robust model system. We recently demonstrated that human pluripotent stem cells can differentiate into spermatogonial stem cells/spermatogonia, primary and secondary spermatocytes, and haploid spermatids; a model that mimics many aspects of human spermatogenesis. Here, using this model system, we examine the effects of 2-bromopropane (2-BP and 1,2,dibromo-3-chloropropane (DBCP on in vitro human spermatogenesis. 2-BP and DBCP are non-endocrine disrupting toxicants that are known to impact male fertility. We show that acute treatment with either 2-BP or DBCP induces a reduction in germ cell viability through apoptosis. 2-BP and DBCP affect viability of different cell populations as 2-BP primarily reduces spermatocyte viability, whereas DBCP exerts a much greater effect on spermatogonia. Acute treatment with 2-BP or DBCP also reduces the percentage of haploid spermatids. Both 2-BP and DBCP induce reactive oxygen species (ROS formation leading to an oxidized cellular environment. Taken together, these results suggest that acute exposure with 2-BP or DBCP causes human germ cell death in vitro by inducing ROS formation. This system represents a unique platform for assessing human reproductive toxicity potential of various environmental toxicants in a rapid, efficient, and unbiased format.

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

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.

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

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....

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

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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.

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)

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...

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.

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

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...

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.

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...

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.

Functions of TAM RTKs in regulating spermatogenesis and male fertility in mice.

Science.gov (United States)

Chen, Yongmei; Wang, Huizhen; Qi, Nan; Wu, Hui; Xiong, Weipeng; Ma, Jing; Lu, Qingxian; Han, Daishu

2009-10-01

Mice lacking TYRO3, AXL and MER (TAM) receptor tyrosine kinases (RTKs) are male sterile. The mechanism of TAM RTKs in regulating male fertility remains unknown. In this study, we analyzed in more detail the testicular phenotype of TAM triple mutant (TAM(-/-)) mice with an effort to understand the mechanism. We demonstrate that the three TAM RTKs cooperatively regulate male fertility, and MER appears to be more important than AXL and TYRO3. TAM(-/-) testes showed a progressive loss of germ cells from elongated spermatids to spermatogonia. Young adult TAM(-/-) mice exhibited oligo-astheno-teratozoospermia and various morphological malformations of sperm cells. As the mice aged, the germ cells were eventually depleted from the seminiferous tubules. Furthermore, we found that TAM(-/-) Sertoli cells have an impaired phagocytic activity and a large number of differentially expressed genes compared to wild-type controls. By contrast, the function of Leydig cells was not apparently affected by the mutation of TAM RTKs. Therefore, we conclude that the suboptimal function of Sertoli cells leads to the impaired spermatogenesis in TAM(-/-) mice. The results provide novel insight into the mechanism of TAM RTKs in regulating male fertility.

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.

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

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.

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.

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.)

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)

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.

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)

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)

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.

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:

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.

Localisation of RNAs into the germ plasm of vitellogenic Xenopus oocytes.

Directory of Open Access Journals (Sweden)

Sarbjit Nijjar

Full Text Available We have studied the localisation of mRNAs in full-grown Xenopus laevis oocytes by injecting fluorescent RNAs, followed by confocal microscopy of the oocyte cortex. Concentrating on RNA encoding the Xenopus Nanos homologue, nanos1 (formerly Xcat2, we find that it consistently localised into aggregated germ plasm ribonucleoprotein (RNP particles, independently of cytoskeletal integrity. This implies that a diffusion/entrapment-mediated mechanism is active, as previously reported for previtellogenic oocytes. Sometimes this was accompanied by localisation into scattered particles of the "late", Vg1/VegT pathway; occasionally only late pathway localisation was seen. The Xpat RNA behaved in an identical fashion and for neither RNA was the localisation changed by any culture conditions tested. The identity of the labelled RNP aggregates as definitive germ plasm was confirmed by their inclusion of abundant mitochondria and co-localisation with the germ plasm protein Hermes. Further, the nanos1/Hermes RNP particles are interspersed with those containing the germ plasm protein Xpat. These aggregates may be followed into the germ plasm of unfertilized eggs, but with a notable reduction in its quantity, both in terms of injected molecules and endogenous structures. Our results conflict with previous reports that there is no RNA localisation in large oocytes, and that during mid-oogenesis even germ plasm RNAs localise exclusively by the late pathway. We find that in mid oogenesis nanos1 RNA also localises to germ plasm but also by the late pathway. Late pathway RNAs, Vg1 and VegT, also may localise into germ plasm. Our results support the view that mechanistically the two modes of localisation are extremely similar, and that in an injection experiment RNAs might utilise either pathway, the distinction in fates being very subtle and subject to variation. We discuss these results in relation to their biological significance and the results of others.

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.

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.

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 ...

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 ...

Comparison of the effects of bisphenol A alone and in a combination with X-irradiation on sperm count and quality in male adult and pubescent mice.

Science.gov (United States)

Dobrzyńska, Małgorzata M; Jankowska-Steifer, Ewa A; Tyrkiel, Ewa J; Gajowik, Aneta; Radzikowska, Joanna; Pachocki, Krzysztof A

2014-11-01

Bisphenol A (BPA) is employed in the manufacturing of epoxy, polyester-styrene, and polycarbonate resins, which are used for the production of baby and water bottles and reusable containers, food and beverage packing, dental fillings and sealants. The study was designed to examine the effects of 8-week exposure (a full cycle of spermatogenesis) to BPA alone and in a combination with X-irradiation on the reproductive organs and germ cells of adult and pubescent male mice. Pzh:Sfis male mice were exposed to BPA (5, 10, and 20 mg/kg) or X-rays (0.05 Gy) or to a combination of both (0.05 Gy + 5 mg/kg bw BPA). The following parameters were examined: sperm count, sperm motility, sperm morphology, and DNA damage in male gametes. Both BPA and X-rays alone diminished sperm quality. BPA exposure significantly reduced sperm count in pubescent males compared to adult mice, with degenerative changes detected in seminiferous epithelium. This may suggest a higher susceptibility of germ cells of younger males to BPA action. Combined BPA with X-ray treatment enhanced the harmful effect induced by BPA alone in male germ cells of adult males, whereas low-dose irradiation showed sometimes protective or additive effects in pubescent mice. Copyright © 2013 Wiley Periodicals, Inc., a Wiley company.

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 ...

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 ...

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.

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 ...

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.

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.

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

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.

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

The male reproductive system of Hippolyte inermis Leach 1815 (Decapoda, Caridea)

Science.gov (United States)

Cobos, Vanesa; Díaz, Vanessa; Raso, Jose Enrique García; Manjón-Cabeza, M. E.

2011-03-01

The present work completes a series of studies on the biology of the shrimp Hippolyte inermis Leach 1815, where we suggested the species to be gonochoristic. The morphology of the male reproductive system (testes, vasa deferentia, gonopores) and the different stages of male germ cell development are described for the first time in the genus Hippolyte, using TEM, SEM, and histological methods. All males from 1.70 to 3.42 mm in carapace length had active testes and well-developed vasa deferentia. No case of sex reversal could be found.

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...

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.

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

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

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

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...

Modeling cell elongation during germ band retraction: cell autonomy versus applied anisotropic stress

International Nuclear Information System (INIS)

Lynch, Holley E; Shane Hutson, M; Veldhuis, Jim; Wayne Brodland, G

2014-01-01

The morphogenetic process of germ band retraction in Drosophila embryos involves coordinated movements of two epithelial tissues—germ band and amnioserosa. The germ band shortens along its rostral–caudal or head-to-tail axis, widens along its perpendicular dorsal-ventral axis, and uncurls from an initial ‘U’ shape. The amnioserosa mechanically assists this process by pulling on the crook of the U-shaped germ band. The amnioserosa may also provide biochemical signals that drive germ band cells to change shape in a mechanically autonomous fashion. Here, we use a finite-element model to investigate how these two contributions reshape the germ band. We do so by modeling the response to laser-induced wounds in each of the germ band’s spatially distinct segments (T1–T3, A1–A9) during the middle of retraction when segments T1–A3 form the ventral arm of the ‘U’, A4–A7 form its crook, and A8–A9 complete the dorsal arm. We explore these responses under a range of externally applied stresses and internal anisotropy of cell edge tensions—akin to a planar cell polarity that can drive elongation of cells in a direction parallel to the minimum edge tension—and identify regions of parameter space (edge-tension anisotropy versus stress anisotropy) that best match previous experiments for each germ band segment. All but three germ band segments are best fit when the applied stress anisotropy and the edge-tension anisotropy work against one another—i.e., when the isolated effects would elongate cells in perpendicular directions. Segments in the crook of the germ band (A4–A7) have cells that elongate in the direction of maximum external stress, i.e., external stress anisotropy is dominant. In most other segments, the dominant factor is internal edge-tension anisotropy. These results are consistent with models in which the amnioserosa pulls on the crook of the germ band to mechanically assist retraction. In addition, they suggest a mechanical cue for

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...

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...

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 ...

The induction by X-rays of chromosome aberrations in male guinea-pigs, golden hamsters and rabbits

International Nuclear Information System (INIS)

Cox, B.D.; Lyon, M.F.

1975-01-01

Translocations induced by X-rays in post-meiotic germ cells of male guinea-pigs, golden hamsters and rabbits were studied cytologically in the F 1 sons of the irradiated males. The percentage of spermatocytes displaying multivalent configurations varied with the translocation, but the average percentage appeared to depend on the species: fewer quadrivalents were observed in hamster than in guinea-pig heterozygotes and most were recorded for rabbit heterozygotes. Chain quadrivalents were more abundant than ring quadrivalents at meiosis for the guinea-pig and hamster in contrast to the mouse. Too few translocation heterozygotes were examined to determine which meiotic configuration was the more prevalent in the rabbit. In all three species, as in the mouse, translocations were found which caused male sterility, due to partial or complete failure of spermatogenesis, although most translocations caused semi-sterility. For these semi-sterile males both the frequency and time of embryonic death in the progeny appeared to be the same as in the mouse. It is concluded that similar types of chromosome aberrations are induced by X-rays in post-meiotic germ cells of male guinea-pigs, rabbits, golden hamsters and mice

Sexual dimorphic expression of dnd in germ cells during sex reversal and its requirement for primordial germ cell survival in protogynous hermaphroditic grouper.

Science.gov (United States)

Sun, Zhi-Hui; Zhou, Li; Li, Zhi; Liu, Xiao-Chun; Li, Shui-Sheng; Wang, Yang; Gui, Jian-Fang

2017-06-01

Dead end (dnd), vertebrate-specific germ cell marker, had been demonstrated to be essential for primordial germ cell (PGC) migration and survival, and the link between PGC number and sex change had been revealed in some teleost species, but little is known about dnd in hermaphroditic vertebrates. In the present study, a protogynous hermaphroditic orange-spotted grouper (Epinephelus coioides) dnd homologue (Ecdnd) was identified and characterized. Quantitative real-time PCR and in situ hybridization analysis revealed a dynamic and sexually dimorphic expression pattern in PGCs and germ cells of gonads. During sex changing, the Ecdnd transcript sharply increased in early transitional gonad, reached the highest level at late transitional gonad stage, and decreased after testis maturation. Visualization of zebrafish PGCs by injecting with RFP-Ecdnd-3'UTR RNA and GFP-zfnanos3-3'UTR RNA confirmed importance of Ecdnd 3'UTR for the PGC distribution. In addition, knockdown of EcDnd by using antisense morpholinos (MO) caused the ablation of PGCs in orange-spotted grouper. Therefore, the current data indicate that Ecdnd is essential for PGCs survival and may serve as a useful germ cell marker during gametogenesis in hermaphroditic grouper. Copyright © 2017 Elsevier Inc. All rights reserved.

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.

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

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

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...

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.

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

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...

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)

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

Neighboring genes for DNA-binding proteins rescue male sterility in Drosophila hybrids.

Science.gov (United States)

Liénard, Marjorie A; Araripe, Luciana O; Hartl, Daniel L

2016-07-19

Crosses between closely related animal species often result in male hybrids that are sterile, and the molecular and functional basis of genetic factors for hybrid male sterility is of great interest. Here, we report a molecular and functional analysis of HMS1, a region of 9.2 kb in chromosome 3 of Drosophila mauritiana, which results in virtually complete hybrid male sterility when homozygous in the genetic background of sibling species Drosophila simulans. The HMS1 region contains two strong candidate genes for the genetic incompatibility, agt and Taf1 Both encode unrelated DNA-binding proteins, agt for an alkyl-cysteine-S-alkyltransferase and Taf1 for a subunit of transcription factor TFIID that serves as a multifunctional transcriptional regulator. The contribution of each gene to hybrid male sterility was assessed by means of germ-line transformation, with constructs containing complete agt and Taf1 genomic sequences as well as various chimeric constructs. Both agt and Taf1 contribute about equally to HMS1 hybrid male sterility. Transgenes containing either locus rescue sterility in about one-half of the males, and among fertile males the number of offspring is in the normal range. This finding suggests compensatory proliferation of the rescued, nondysfunctional germ cells. Results with chimeric transgenes imply that the hybrid incompatibilities result from interactions among nucleotide differences residing along both agt and Taf1 Our results challenge a number of preliminary generalizations about the molecular and functional basis of hybrid male sterility, and strongly reinforce the role of DNA-binding proteins as a class of genes contributing to the maintenance of postzygotic reproductive isolation.

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.

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.

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.

Proteínas do feijão preto sem casca: digestibilidade em animais convencionais e isentos de germes (germ-free Proteins of dehulled black beans: digestibility in conventional and germ-free animals

Directory of Open Access Journals (Sweden)

Conceição Angelina dos Santos PEREIRA

2002-01-01

Full Text Available O feijão (Phaseolus vulgaris, L. é uma leguminosa de grande importância para a dieta da população brasileira. No entanto, um de seus maiores problemas é representado pelo baixo valor nutricional de suas proteínas, decorrente, por um lado, da sua baixa digestibilidade e, de outro, do teor e biodisponibilidade reduzidos de aminoácidos sulfurados. Com o objetivo de avaliar a digestibilidade das proteínas albumina e globulina do feijão preto sem casca, foram realizados ensaios biológicos com camundongos isentos de germes e convencionais e com ratos (Wistar, recém-desmamados, com idade de 21 a 25 dias. Avaliou-se ainda o Escore Químico Corrigido pela Digestibilidade da Proteína. A digestibilidade verdadeira no experimento com camundongos isentos de germes foi de 90,21 e 90,00%, no teste com camundongos convencionais foi de 85,53 e 86,73%, e no experimento com ratos foi de 82,62 e 68,53%, para albumina e globulina, respectivamente. O Escore Químico Corrigido pela Digestibilidade da Proteína foi de 61,00% para a albumina e 51,00% para a globulina. A digestibilidade determinada em animais isentos de germes foi superior aos valores encontrados em animais convencionais, sugerindo que a flora intestinal esteja contribuindo para elevar o teor de nitrogênio nas fezes dos animais convencionais, e, portanto, esteja sendo subestimada a digestibilidade verdadeira do feijão.The bean (Phaseolus vulgaris, L. is a legume of great importance in the Brazilian typical diet. Nevertheless, it presents a low protein quality due to its poor digestibility and low levels and bioavailability of its sulfur aminoacids. The aim of this study was to evaluate the digestibility of albumin and globulin protein fractions of dehulled black beans in conventional and germ-free mice and also in weaning rats (Wistar of 21 to 25 days of age. Protein Digestibility Corrected Amino Acid Score was also determined. True digestibility values in germ-free mice were 90.21 and 90

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

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...

Primary Germ Cell Tumors of the Mediastinum: 10 Years of Experience in a Tertiary Teaching Hospital

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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.

Multidimensional representations: The knowledge domain of germs held by students, teachers and medical professionals

Science.gov (United States)

Rua, Melissa Jo

The present study examined the understandings held by 5th, 8th, and 11th-grade students, their teachers and medical professionals about germs. Specifically, this study describes the content and structure of students' and adults' conceptions in the areas of germ contraction, transmission, and treatment of infectious and non-infectious diseases caused by microorganisms. Naturalistic and empirical research methods were used to investigate participants' conceptions. Between and within group similarities were found using data from concept maps on the topic "flu," drawings of germs, a 20 word card sort related to germs and illness, and a semi-structured interview. Concept maps were coded according to techniques by Novak and Gowan (1984). Drawings of germs were coded into four main categories (bacteria, viruses, animal cell, other) and five subcategories (disease, caricature, insect, protozoa, unclassified). Cluster patterns for the card sorts of each group were found using multidimensional scaling techniques. Six coding categories emerged from the interview transcripts: (a) transmission, (b) treatment, (c) effect of weather on illness, (d) immune response, (e) location of germs, and (f) similarities and differences between bacteria and viruses. The findings showed students, teachers and medical professionals have different understandings about bacteria and viruses and the structures of those understandings vary. Gaps or holes in the participants knowledge were found in areas such as: (a) how germs are transmitted, (b) where germs are found, (c) how the body transports and uses medicine, (d) how the immune system functions, (e) the difference between vaccines and non-prescription medicines, (f) differences that exist between bacteria and viruses, and (g) bacterial resistance to medication. The youngest students relied heavily upon personal experiences with germs rather than formal instruction when explaining their conceptions. As a result, the influence of media was

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

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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

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.

Premeiotic germ cell defect in seminiferous tubules of Atm-null testis

International Nuclear Information System (INIS)

Takubo, Keiyo; Hirao, Atsushi; Ohmura, Masako; Azuma, Masaki; Arai, Fumio; Nagamatsu, Go; Suda, Toshio

2006-01-01

Lifelong spermatogenesis is maintained by coordinated sequential processes including self-renewal of stem cells, proliferation of spermatogonial cells, meiotic division, and spermiogenesis. It has been shown that ataxia telangiectasia-mutated (ATM) is required for meiotic division of the seminiferous tubules. Here, we show that, in addition to its role in meiosis, ATM has a pivotal role in premeiotic germ cell maintenance. ATM is activated in premeiotic spermatogonial cells and the Atm-null testis shows progressive degeneration. In Atm-null testicular cells, differing from bone marrow cells of Atm-null mice, reactive oxygen species-mediated p16 Ink4a activation does not occur in Atm-null premeiotic germ cells, which suggests the involvement of different signaling pathways from bone marrow defects. Although Atm-null bone marrow undergoes p16 Ink4a -mediated cellular senescence program, Atm-null premeiotic germ cells exhibited cell cycle arrest and apoptotic elimination of premeiotic germ cells, which is different from p16 Ink4a -mediated senescence

Control over the morphology and segregation of Zebrafish germ cell granules during embryonic development

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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.

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

Effects of environmental Bisphenol A exposures on germ cell development and Leydig cell function in the human fetal testis.

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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.

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...

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

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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.

"Mixed germ cell testicular tumor" in an adult female

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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.

Male patients presenting with rapidly progressive puberty associated with malignant tumors

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Soo Jung Kim

2016-03-01

Full Text Available In males, precocious puberty (PP is defined as the development of secondary sexual characteristics before age 9 years. PP is usually idiopathic; though, organic abnormalities including tumors are more frequently found in male patients with PP. However, advanced puberty in male also can be an important clinical manifestation in tumors. We report 2 cases of rapidly progressive puberty in males, each associated with a germ-cell tumor. First, an 11-year-old boy presented with mild fever and weight loss for 1 month. Physical examination revealed a pubertal stage of G3P3 with 10-mL testes. Investigations revealed advanced bone age (16 years with elevated basal luteinizing hormone and testosterone levels. An anterior mediastinal tumor was identified by chest radiography and computed tomography, and elevated α-fetoprotein (AFP and β-human chorionic gonadotropin (β-hCG levels were noted. Histopathologic analysis confirmed a yolk-sac tumor. Second, a 12-year-old boy presented with diplopia, polydipsia, and polyuria for 4 months. Physical examination revealed a pubertal stage of G3P3 with 8-mL testes. Bone age was advanced (16 years and laboratory tests indicated panhypopituitarism with elevated testosterone level. A mixed germ-cell tumor was diagnosed with elevated AFP and β-hCG levels. Of course, these patients also have other symptoms of suspecting tumors, however, rapidly progressive puberty can be the more earlier screening sign of tumors. Therefore, in male patients with accelerated or advanced puberty, malignancy should be considered, with evaluation of tumor markers. In addition, advanced puberty in male should be recognized more widely as a unique sign of neoplasm.

Effects of β-glucan polysaccharide revealed by the dominant lethal assay and micronucleus assays, and reproductive performance of male mice exposed to cyclophosphamide

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Rodrigo Juliano Oliveira

2014-01-01

Full Text Available β-glucan is a well-known polysaccharide for its chemopreventive effect. This study aimed to evaluate the chemopreventive ability of β-glucan in somatic and germ cells through the dominant lethal and micronucleus assays, and its influence on the reproductive performance of male mice exposed to cyclophosphamide. The results indicate that β-glucan is capable of preventing changes in DNA in both germ cells and somatic ones. Changes in germ cells were evaluated by the dominant lethal assay and showed damage reduction percentages of 46.46% and 43.79% for the doses of 100 and 150 mg/kg. For the somatic changes, evaluated by micronucleus assay in peripheral blood cells in the first week of treatment, damage reduction percentages from 80.63-116.32% were found. In the fifth and sixth weeks, the percentage ranged from 10.20-52.54% and -0.95-62.35%, respectively. Besides the chemopreventive efficiency it appears that the β-glucan, when combined with cyclophosphamide, is able to improve the reproductive performance of males verified by the significant reduction in rates of post-implantation losses and reabsorption in the mating of nulliparous females with males treated with cyclophosphamide.

Primary Germ Cell Tumor of Testes with Extensive Lymph Nodal and Splenic Metastases Masquerading Lymphoma on 18-F-FDG PET/CT

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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

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...

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

Urethral metastasis from non-seminomatous germ cell tumor: a case report

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Joffe Johnathan

2011-01-01

Full Text Available Abstract Introduction We present a case of nonseminomatous germ cell tumor of the testes with acute urinary retention secondary to urethral metastasis. This presentation, and similar cases of urethral metastasis from this tumor, have not been reported previously. Case presentation A 35-year-old Caucasian man presented to hospital with a history of acute urinary retention. On examination he was found to have right testicular enlargement with raised β-human chorionic gonadotrophin, serum α-fetoprotein and lactate dehydrogenase levels. He underwent radical left inguinal orchidectomy and histology confirmed a nonseminomatous germ cell tumor of the testes. Cystoscopy carried out due to urinary retention showed penile metastasis and the biopsy confirmed metastatic malignant undifferentiated teratoma. Staging computed tomography scan and magnetic resonance imaging of the pelvis showed pulmonary, pelvic nodal, ischial and penile metastasis. The diagnosis of the International Germ Cell Cancer Collaborative Group of poor prognosis metastatic nonseminomatous germ cell tumor was made, following which he received four cycles of bleomycin, etoposide and cisplatin chemotherapy with curative intent. He had a complete marker and an excellent radiological response. He is currently under follow up. Conclusion The unusual presentation of lymphovascular spread in this case of nonseminomatous germ cell tumor highlights the need to include routine pelvic imaging in the assessment and follow up of testicular cancer.

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

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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.

EKSTRAKSI DAN ANALISIS FITOSTEROL LEMBAGA GANDUM [Extraction and analysis of Phytosterol from wheat germ (Triticum sp.

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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.

ASSESSMENT OF MALE INFERTILITY BY TESTICULAR BIOPSY IN SOUTHERN ODISHA

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Sujata Naik

2017-10-01

Full Text Available BACKGROUND Infertility continues to be a significant problem since ages. Studies suggest that the problem affects 8-12% of couples across the globe, and among these affected couples, approximately 50% cases are contributed by the male partner. Semen analysis is the first investigation that indicates towards male factor in infertility. Finding the cause of infertility in cases of severe oligozoospermia and azoospermia by evaluating testicular biopsies has now become essential with the availability of Assisted Reproductive Techniques (ART, which gives information about the level of spermatogenesis. The present study was undertaken to detect the histological findings in cases of male infertility in this geographic region. MATERIALS AND METHODS A prospective cross-sectional study was undertaken in which testicular biopsies received from 52 infertile male patients with seminogram impressions of very severe oligozoospermia and azoospermia constituted the study group. Detailed clinical data including the LH. FSH and testosterone hormone levels were recorded. Tissue samples were routinely processed and Haematoxylin and Eosin stained were made. Modified Johnsen scoring was used to categorise each case. RESULTS 86.5% cases in the study group were found to have azoospermia and rest 13.5% cases had severe oligozoospermia. All the cases were histologically classified into six categories- obstructive pathology 25 of 52 cases (48.1%, pure germ cell aplasia 14 of 52 cases (26.9%, maturation arrest 7 of 52 cases (13.5%, atrophic testis 4 of 52 cases (7.7%, hypospermatogenesis 1 of 52 cases (1.9% and inconclusive in 1 of 52 cases. Serum FSH and serum LH levels were found significantly raised in cases of pure germ cell aplasia and atrophic testis in contrast cases of obstructive aetiology had normal levels. Modified Johnsen scoring values were 9 in cases with obstructive pathology, 1/2 only in cases of pure germ cell aplasia and atrophic testes and 3 to 6 in cases

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.

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

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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.

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

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

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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.

Fatty acid composition of maize germ oil from high-oil hybrids wet-milling processing

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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.

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.

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

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

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

Direct but no transgenerational effects of decitabine and vorinostat on male fertility.

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Ruth Kläver

Full Text Available Establishment and maintenance of the correct epigenetic code is essential for a plethora of physiological pathways and disturbed epigenetic patterns can provoke severe consequences, e.g. tumour formation. In recent years, epigenetic drugs altering the epigenome of tumours actively have been developed for anti-cancer therapies. However, such drugs could potentially also affect other physiological pathways and systems in which intact epigenetic patterns are essential. Amongst those, male fertility is one of the most prominent. Consequently, we addressed possible direct effects of two epigenetic drugs, decitabine and vorinostat, on both, the male germ line and fertility. In addition, we checked for putative transgenerational epigenetic effects on the germ line of subsequent generations (F1-F3. Parental adult male C57Bl/6 mice were treated with either decitabine or vorinostat and analysed as well as three subsequent untreated generations derived from these males. Treatment directly affected several reproductive parameters as testis (decitabine & vorinostat and epididymis weight, size of accessory sex glands (vorinostat, the height of the seminiferous epithelium and sperm concentration and morphology (decitabine. Furthermore, after decitabine administration, DNA methylation of a number of loci was altered in sperm. However, when analysing fertility of treated mice (fertilisation, litter size and sex ratio, no major effect of the selected epigenetic drugs on male fertility was detected. In subsequent generations (F1-F3 generations only subtle changes on reproductive organs, sperm parameters and DNA methylation but no overall effect on fertility was observed. Consequently, in mice, decitabine and vorinostat neither affected male fertility per se nor caused marked transgenerational effects. We therefore suggest that both drugs do not induce major adverse effects-in terms of male fertility and transgenerational epigenetic inheritance-when used in anti-cancer-therapies.

Direct but no transgenerational effects of decitabine and vorinostat on male fertility.

Science.gov (United States)

Kläver, Ruth; Sánchez, Victoria; Damm, Oliver S; Redmann, Klaus; Lahrmann, Elisabeth; Sandhowe-Klaverkamp, Reinhild; Rohde, Christian; Wistuba, Joachim; Ehmcke, Jens; Schlatt, Stefan; Gromoll, Jörg

2015-01-01

Establishment and maintenance of the correct epigenetic code is essential for a plethora of physiological pathways and disturbed epigenetic patterns can provoke severe consequences, e.g. tumour formation. In recent years, epigenetic drugs altering the epigenome of tumours actively have been developed for anti-cancer therapies. However, such drugs could potentially also affect other physiological pathways and systems in which intact epigenetic patterns are essential. Amongst those, male fertility is one of the most prominent. Consequently, we addressed possible direct effects of two epigenetic drugs, decitabine and vorinostat, on both, the male germ line and fertility. In addition, we checked for putative transgenerational epigenetic effects on the germ line of subsequent generations (F1-F3). Parental adult male C57Bl/6 mice were treated with either decitabine or vorinostat and analysed as well as three subsequent untreated generations derived from these males. Treatment directly affected several reproductive parameters as testis (decitabine & vorinostat) and epididymis weight, size of accessory sex glands (vorinostat), the height of the seminiferous epithelium and sperm concentration and morphology (decitabine). Furthermore, after decitabine administration, DNA methylation of a number of loci was altered in sperm. However, when analysing fertility of treated mice (fertilisation, litter size and sex ratio), no major effect of the selected epigenetic drugs on male fertility was detected. In subsequent generations (F1-F3 generations) only subtle changes on reproductive organs, sperm parameters and DNA methylation but no overall effect on fertility was observed. Consequently, in mice, decitabine and vorinostat neither affected male fertility per se nor caused marked transgenerational effects. We therefore suggest that both drugs do not induce major adverse effects-in terms of male fertility and transgenerational epigenetic inheritance-when used in anti-cancer-therapies.

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.

Treatment Option Overview (Extragonadal Germ Cell Tumors)

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... 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. ...

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. ...

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...

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...

Deoxyribonucleic acid-deficient strains of Candida albicans.

Science.gov (United States)

Olaiya, A F; Steed, J R; Sogin, S J

1980-03-01

We analyzed a series of germ tube-negative variants isolated from Candida albicans 3153A for deoxyribonucleic acid content. As analyzed by flow microfluorometry, the deoxyribonucleic acid level in these variant strains was 50% of that of the parental strain and equivalent to that of haploid Saccharomyces cerevisiae. This finding was confirmed by comparison of survival rates when exposed to the mutagens ultraviolet light, ethyl methane sulfonate, and methyl methane sulfonate. The diameter of the variant cells as compared to the diameter of the parental 3153A strain showed a relationship similar to that of the diameters of haploid versus diploid S. cerevisiae. These results indicate that those strains may be representative of the imperfect stage of C. albicans.

Characteristics, causes and evolutionary consequences of male-biased mutation.

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Ellegren, Hans

2007-01-07

Mutation has traditionally been considered a random process, but this paradigm is challenged by recent evidence of divergence rate heterogeneity in different genomic regions. One facet of mutation rate variation is the propensity for genetic change to correlate with the number of germ cell divisions, reflecting the replication-dependent origin of many mutations. Haldane was the first to connect this association of replication and mutation to the difference in the number of cell divisions in oogenesis (low) and spermatogenesis (usually high), and the resulting sex difference in the rate of mutation. The concept of male-biased mutation has been thoroughly analysed in recent years using an evolutionary approach, in which sequence divergence of autosomes and/or sex chromosomes are compared to allow inference about the relative contribution of mothers and fathers in the accumulation of mutations. For instance, assuming that a neutral sequence is analysed, that rate heterogeneity owing to other factors is cancelled out by the investigation of many loci and that the effect of ancestral polymorphism is properly taken into account, the male-to-female mutation rate ratio, alpham, can be solved from the observed difference in rate of X and Y chromosome divergence. The male mutation bias is positively correlated with the relative excess of cell divisions in the male compared to the female germ line, as evidenced by a generation time effect: in mammals, alpham is estimated at approximately 4-6 in primates, approximately 3 in carnivores and approximately 2 in small rodents. Another life-history correlate is sexual selection: when there is intense sperm competition among males, increased sperm production will be associated with a larger number of mitotic cell divisions in spermatogenesis and hence an increase in alpham. Male-biased mutation has implications for important aspects of evolutionary biology such as mate choice in relation to mutation load, sexual selection and the

Generation of germ cells in vitro in the era of induced pluripotent stem cells.

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Imamura, Masanori; Hikabe, Orie; Lin, Zachary Yu-Ching; Okano, Hideyuki

2014-01-01

Induced pluripotent stem cells (iPSCs) are stem cells that can be artificially generated via "cellular reprogramming" using gene transduction in somatic cells. iPSCs have enormous potential in stem-cell biology as they can give rise to numerous cell lineages, including the three germ layers. An evaluation of germ-line competency by blastocyst injection or tetraploid complementation, however, is critical for determining the developmental potential of mouse iPSCs towards germ cells. Recent studies have demonstrated that primordial germ cells obtained by the in vitro differentiation of iPSCs produce functional gametes as well as healthy offspring. These findings illustrate not only that iPSCs are developmentally similar to embryonic stem cells (ESCs), but also that somatic cells from adult tissues can produce gametes in vitro, that is, if they are reprogrammed into iPSCs. In this review, we discuss past and recent advances in the in vitro differentiation of germ cells using pluripotent stem cells, with an emphasis on ESCs and iPSCs. While this field of research is still at a stage of infancy, it holds great promises for investigating the mechanisms of germ-cell development, especially in humans, and for advancing reproductive and developmental engineering technologies in the future. © 2013 Wiley Periodicals, Inc.

Ghrelin modulates testicular germ cells apoptosis and proliferation in adult normal rats

International Nuclear Information System (INIS)

Kheradmand, Arash; Dezfoulian, Omid; Alirezaei, Masoud; Rasoulian, Bahram

2012-01-01

Highlights: ► Spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. ► Numerous studies have documented the direct action of ghrelin in the modulation of apoptosis in different cell types. ► Ghrelin may be considered as a modulator of spermatogenesis in normal adult rats. ► Ghrelin may be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors. -- Abstract: Under normal condition in the most mammals, spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. The present study was designed to determine the effects of ghrelin treatment on in vivo quality and quantity expression of apoptosis and proliferation specific indices in rat testicular germ cells. Twenty eight adult normal rats were subdivided into equal control and treatment groups. Treatment group received 3 nmol of ghrelin as subcutaneous injection for 30 consecutive days or vehicle to the control animals. The rats from each group (n = 7) were killed on days 10 and 30 and their testes were taken for immunocytochemical evaluation and caspase-3 assay. Immunohistochemical analysis indicated that the accumulations of Bax and PCNA peptides are generally more prominent in spermatocytes and spermatogonia of both groups. Likewise, the mean percentage of immunoreactive spermatocytes against Bax increased (P 0.05). Upstream of Bax substance parallel to down-regulation of PCNA demonstrate that ghrelin may prevent massive accumulation of germ cells during normal spermatogenesis. These observations also indicate that ghrelin may be considered as a modulator of spermatogenesis in normal adult rats and could be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors.

Patterns of Glycoconjugate Distribution during Molar Tooth Germ Development in Mice

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AR. Varasteh

2007-09-01

Full Text Available Objective: The aim of the present study was to evaluate the structure and distribution of Glycoconjugates during molar tooth germ development in mice.Materials and Methods: Sixteen tooth germs were obtained from BALB/c mice embryos 15 to 18 days post-gestation and fixed in 10% formalin. After routine tissue processing, 5μm sections were cut and stained with BSA1-B4 and PNA using the lectin histochemical method. All slides were evaluated by light microscopy.Results: Both lectins showed positive reaction in the tooth germ but with spatiotemporal differences. During bell stage, the reaction was strong with BSA1-B4 but moderate with PNA. Strong PNA uptake was observed in the odontoblastic and ameloblastic nuclei alongwith the apical cytoplasm of the ameloblasts.Conclusion: Although the lectins that were used in the present study recognize the same terminal sugar residue, they reacted with different disaccharide sequences with various penaltomer sugars. Therefore it may be assumed that the pattern of affinity for different parts of the developing tooth germ such as ameloblasts and odontoblasts is different in various lectins.

Neurl4 contributes to germ cell formation and integrity in Drosophila

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Jennifer Jones

2015-08-01

Full Text Available Primordial germ cells (PGCs form at the posterior pole of the Drosophila embryo, and then migrate to their final destination in the gonad where they will produce eggs or sperm. Studies of the different stages in this process, including assembly of germ plasm in the oocyte during oogenesis, specification of a subset of syncytial embryonic nuclei as PGCs, and migration, have been informed by genetic analyses. Mutants have defined steps in the process, and the identities of the affected genes have suggested biochemical mechanisms. Here we describe a novel PGC phenotype. When Neurl4 activity is reduced, newly formed PGCs frequently adopt irregular shapes and appear to bud off vesicles. PGC number is also reduced, an effect exacerbated by a separate role for Neurl4 in germ plasm formation during oogenesis. Like its mammalian homolog, Drosophila Neurl4 protein is concentrated in centrosomes and downregulates centrosomal protein CP110. Reducing CP110 activity suppresses the abnormal PGC morphology of Neurl4 mutants. These results extend prior analyses of Neurl4 in cultured cells, revealing a heightened requirement for Neurl4 in germ-line cells in Drosophila.

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.

Treatment Option Overview (Ovarian Germ Cell Tumors)

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... 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 ...

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.

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.

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 ...

Genetic and epigenetic factors: Role in male infertility

Directory of Open Access Journals (Sweden)

M B Shamsi

2011-01-01

Full Text Available Genetic factors contribute upto 15%-30% cases of male infertility. Formation of spermatozoa occurs in a sequential manner with mitotic, meiotic, and postmeiotic differentiation phases each of which is controlled by an intricate genetic program. Genes control a variety of physiologic processes, such as hypothalamus-pituitary-gonadal axis, germ cell development, and differentiation. In the era of assisted reproduction technology, it is important to understand the genetic basis of infertility to provide maximum adapted therapeutics and counseling to the couple.

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)

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

Anti-Inflammatory Activity of Citric Acid-Treated Wheat Germ Extract in Lipopolysaccharide-Stimulated Macrophages.

Science.gov (United States)

Jeong, Hee-Yeong; Choi, Yong-Seok; Lee, Jae-Kang; Lee, Beom-Joon; Kim, Woo-Ki; Kang, Hee

2017-07-10

Until recently, fermentation was the only processing used to improve the functionality of wheat germ. The release of 2,6-dimethoxy-1,4-benzoquinone (DMBQ) from hydroquinone glycosides during the fermentation process is considered a marker of quality control. Here, we treated wheat germ extract with citric acid (CWG) to release DMBQ and examined the anti-inflammatory activity of this extract using a lipopolysaccharide-activated macrophage model. Treatment of wheat germ with citric acid resulted in detectable release of DMBQ but reduced total phenolic and total flavonoid contents compared with untreated wheat germ extract (UWG). CWG inhibited secretion of the pro-inflammatory cytokines tumor necrosis factor-α, interleukin (IL)-6, and IL-12 and the synthesis of cyclooxygenase-2, while UWG only decreased IL-12 production. CWG and UWG induced high levels of anti-inflammatory IL-10 and heme oxygenase-1. CWG specifically inhibited phosphorylation of NF-κB p65 and p38 kinase at 15 min after LPS stimulation. Our study showed that citric acid treatment enhanced the anti-inflammatory activity of wheat germ extract.

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.

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...

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:...

DNA methylation profiling of embryonic stem cell differentiation into the three germ layers.

Science.gov (United States)

Isagawa, Takayuki; Nagae, Genta; Shiraki, Nobuaki; Fujita, Takanori; Sato, Noriko; Ishikawa, Shumpei; Kume, Shoen; Aburatani, Hiroyuki

2011-01-01

Embryogenesis is tightly regulated by multiple levels of epigenetic regulation such as DNA methylation, histone modification, and chromatin remodeling. DNA methylation patterns are erased in primordial germ cells and in the interval immediately following fertilization. Subsequent developmental reprogramming occurs by de novo methylation and demethylation. Variance in DNA methylation patterns between different cell types is not well understood. Here, using methylated DNA immunoprecipitation and tiling array technology, we have comprehensively analyzed DNA methylation patterns at proximal promoter regions in mouse embryonic stem (ES) cells, ES cell-derived early germ layers (ectoderm, endoderm and mesoderm) and four adult tissues (brain, liver, skeletal muscle and sperm). Most of the methylated regions are methylated across all three germ layers and in the three adult somatic tissues. This commonly methylated gene set is enriched in germ cell-associated genes that are generally transcriptionally inactive in somatic cells. We also compared DNA methylation patterns by global mapping of histone H3 lysine 4/27 trimethylation, and found that gain of DNA methylation correlates with loss of histone H3 lysine 4 trimethylation. Our combined findings indicate that differentiation of ES cells into the three germ layers is accompanied by an increased number of commonly methylated DNA regions and that these tissue-specific alterations in methylation occur for only a small number of genes. DNA methylation at the proximal promoter regions of commonly methylated genes thus appears to be an irreversible mark which functions to fix somatic lineage by repressing the transcription of germ cell-specific genes.

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.)

3D modeling of genome macroorganization on the basis of its structural changes after action of radiation

International Nuclear Information System (INIS)

Aleksandrov, I.D.; Aleksandrova, M.V.; Zaikin, N.S.; Koren'kov, V.V.; Pervushova, O.V.; Stepanenko, V.A.

2006-01-01

At present, after 120 years of the theoretical and experimental works, the issue of the genome macroarchitecture as the highest level of interphase chromosome organization in somatic cell nuclei remains still unresolved. The problem of the spatial arrangement of interphase chromosomes in haploid germ cells has never even been studied. A 3D simulation of packaging of the entire second chromosome in Drosophila mature sperms has been performed by using mathematical approaches and visualization methods to present macromolecular structure data. As genetic markers for simulation, frequency and location of the second inversion breakpoints for 72 structural υg mutants induced by ionizing radiation were used supposing that both ends of each inversion are topologically brought together forming loop of appropriate size. For the account of a degree of spatial affinity and visualization of chromosomal loops modern 3D-modeling methods with application of splines, libraries OpenGL, language Delphi, program Gmax were used. According to the model proposed, the entire second chromosome within mature sperm nuclei seems to be packaged in the form of a megarosette-loop structure which may be a basic principle of organization of the genome macro-architecture in animal haploid germ cells

Minichromosome maintenance helicase paralog MCM9 is dispensible for DNA replication but functions in germ-line stem cells and tumor suppression.

Science.gov (United States)

Hartford, Suzanne A; Luo, Yunhai; Southard, Teresa L; Min, Irene M; Lis, John T; Schimenti, John C

2011-10-25

Effective DNA replication is critical to the health and reproductive success of organisms. The six MCM2-7 proteins, which form the replicative helicase, are essential for high-fidelity replication of the genome. Many eukaryotes have a divergent paralog, MCM9, that was reported to be essential for loading MCM2-7 onto replication origins in the Xenopus oocyte extract system. To address the in vivo role of mammalian MCM9, we created and analyzed the phenotypes of mice with various mutations in Mcm9 and an intronic DNA replication-related gene Asf1a. Ablation of Mcm9 was compatible with cell proliferation and mouse viability, showing that it is nonessential for MCM2-7 loading or DNA replication. Mcm9 mutants underwent p53-independent embryonic germ-cell depletion in both sexes, with males also exhibiting defective spermatogonial stem-cell renewal. MCM9-deficient cells had elevated genomic instability and defective cell cycle reentry following replication stress, and mutant animals were prone to sex-specific cancers, most notably hepatocellular carcinoma in males. The phenotypes of mutant mice and cells suggest that MCM9 evolved a specialized but nonessential role in DNA replication or replication-linked quality-control mechanisms that are especially important for germ-line stem cells, and also for tumor suppression and genome maintenance in the soma.

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.)

Germ cell specification and ovary structure in the rotifer Brachionus plicatilis.

Science.gov (United States)

Smith, James M; Cridge, Andrew G; Dearden, Peter K

2010-08-02

The segregation of the germline from somatic tissues is an essential process in the development of all animals. Specification of the primordial germ cells (PGCs) takes place via different strategies across animal phyla; either specified early in embryogenesis by the inheritance of maternal determinants in the cytoplasm of the oocyte ('preformation') or selected later in embryonic development from undifferentiated precursors by a localized inductive signal ('epigenesis'). Here we investigate the specification and development of the germ cells in the rotifer Brachionus plicatilis, a member of the poorly-characterized superphyla Lophotrochozoa, by isolating the Brachionus homologues of the conserved germ cell markers vasa and nanos, and examining their expression using in situ hybridization. Bpvasa and Bpnos RNA expression have very similar distributions in the Brachionus ovary, showing ubiquitous expression in the vitellarium, with higher levels in the putative germ cell cluster. Bpvas RNA expression is present in freshly laid eggs, remaining ubiquitous in embryos until at least the 96 cell stage after which expression narrows to a small cluster of cells at the putative posterior of the embryo, consistent with the developing ovary. Bpnos RNA expression is also present in just-laid eggs but expression is much reduced by the four-cell stage and absent by the 16-cell stage. Shortly before hatching of the juvenile rotifer from the egg, Bpnos RNA expression is re-activated, located in a subset of posterior cells similar to those expressing Bpvas at the same stage. The observed expression of vasa and nanos in the developing B. plicatilis embryo implies an epigenetic origin of primordial germ cells in Rotifer.

Germ cell specification and ovary structure in the rotifer Brachionus plicatilis

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Smith James M

2010-08-01

Full Text Available Abstract Background The segregation of the germline from somatic tissues is an essential process in the development of all animals. Specification of the primordial germ cells (PGCs takes place via different strategies across animal phyla; either specified early in embryogenesis by the inheritance of maternal determinants in the cytoplasm of the oocyte ('preformation' or selected later in embryonic development from undifferentiated precursors by a localized inductive signal ('epigenesis'. Here we investigate the specification and development of the germ cells in the rotifer Brachionus plicatilis, a member of the poorly-characterized superphyla Lophotrochozoa, by isolating the Brachionus homologues of the conserved germ cell markers vasa and nanos, and examining their expression using in situ hybridization. Results Bpvasa and Bpnos RNA expression have very similar distributions in the Brachionus ovary, showing ubiquitous expression in the vitellarium, with higher levels in the putative germ cell cluster. Bpvas RNA expression is present in freshly laid eggs, remaining ubiquitous in embryos until at least the 96 cell stage after which expression narrows to a small cluster of cells at the putative posterior of the embryo, consistent with the developing ovary. Bpnos RNA expression is also present in just-laid eggs but expression is much reduced by the four-cell stage and absent by the 16-cell stage. Shortly before hatching of the juvenile rotifer from the egg, Bpnos RNA expression is re-activated, located in a subset of posterior cells similar to those expressing Bpvas at the same stage. Conclusions The observed expression of vasa and nanos in the developing B. plicatilis embryo implies an epigenetic origin of primordial germ cells in Rotifer.

N-cadherin Expression in Testicular Germ Cell and Gonadal Stromal Tumors

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Daniel J. Heidenberg, Joel H. Barton, Denise Young, Michael Grinkemeyer, Isabell A. Sesterhenn

2012-01-01

Full Text Available Neural-cadherin is a member of the cadherin gene family encoding the N-cadherin protein that mediates cell adhesion. N-cadherin is a marker of Sertoli cells and is also expressed in germ cells of varying stages of maturation. The purpose of this study was to determine the presence and distribution of this protein by immunohistochemistry in 105 germ cell tumors of both single and mixed histological types and 12 gonadal stromal tumors. Twenty-four germ cell tumors consisted of one cell type and the remaining were mixed. Of the 23 seminomas in either pure or mixed tumors, 74% were positive. Two spermatocytic seminomas were positive. Of the 83 cases with yolk sac tumor, 99% were positive for N-cadherin. The teratomas were positive in 73% in neuroectodermal and / or glandular components. In contrast, 87% of embryonal carcinomas did not express N-cadherin. Only 17% of the syncytiotrophoblastic cells were positive for N-cadherin. In conclusion, N-cadherin expression is very helpful in the identification of yolk sac tumors. In addition to glypican-3 and Sal-like protein 4, N-cadherin can be beneficial for the diagnosis and classification of this subtype of testicular germ cell tumor. Nine of the 12 gonadal stromal tumors were positive to a variable extent.

Ghrelin modulates testicular germ cells apoptosis and proliferation in adult normal rats

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Kheradmand, Arash, E-mail: arashkheradmand@yahoo.com [Department of Clinical Sciences, School of Veterinary Medicine, Lorestan University, P.O. Box: 465, Khorram Abad (Iran, Islamic Republic of); Dezfoulian, Omid [Department of Pathobiology, School of Veterinary Medicine, Lorestan University, Khorram Abad (Iran, Islamic Republic of); Alirezaei, Masoud [Division of Biochemistry, School of Veterinary Medicine, Lorestan University, P.O. Box: 465, Khorram Abad (Iran, Islamic Republic of); Rasoulian, Bahram [Razi Herbal Medicine Research Center, Lorestan University of Medical Sciences, Khorram Abad (Iran, Islamic Republic of)

2012-03-09

Highlights: Black-Right-Pointing-Pointer Spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. Black-Right-Pointing-Pointer Numerous studies have documented the direct action of ghrelin in the modulation of apoptosis in different cell types. Black-Right-Pointing-Pointer Ghrelin may be considered as a modulator of spermatogenesis in normal adult rats. Black-Right-Pointing-Pointer Ghrelin may be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors. -- Abstract: Under normal condition in the most mammals, spermatogenesis is closely associated with the balance between germ cells proliferation and apoptosis. The present study was designed to determine the effects of ghrelin treatment on in vivo quality and quantity expression of apoptosis and proliferation specific indices in rat testicular germ cells. Twenty eight adult normal rats were subdivided into equal control and treatment groups. Treatment group received 3 nmol of ghrelin as subcutaneous injection for 30 consecutive days or vehicle to the control animals. The rats from each group (n = 7) were killed on days 10 and 30 and their testes were taken for immunocytochemical evaluation and caspase-3 assay. Immunohistochemical analysis indicated that the accumulations of Bax and PCNA peptides are generally more prominent in spermatocytes and spermatogonia of both groups. Likewise, the mean percentage of immunoreactive spermatocytes against Bax increased (P < 0.01) in the ghrelin-treated group on day 10, while despite of 30% increment in the Bax level of spermatocytes in the treated rats on day 30, however, it was not statistically significant. During the experimental period, only a few spermatogonia represented Bax expression and the changes of Bax immunolabling cells were negligible upon ghrelin treatment. Likewise, there were immunostaining cells against Bcl-2 in each germ cell neither in the control nor in the treated animals. In fact

Primordial germ cell-mediated chimera technology produces viable pure-line Houbara bustard offspring: potential for repopulating an endangered species.

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Ulrich Wernery

2010-12-01

Full Text Available The Houbara bustard (Chlamydotis undulata is a wild seasonal breeding bird populating arid sandy semi-desert habitats in North Africa and the Middle East. Its population has declined drastically during the last two decades and it is classified as vulnerable. Captive breeding programmes have, hitherto, been unsuccessful in reviving population numbers and thus radical technological solutions are essential for the long term survival of this species. The purpose of this study was to investigate the use of primordial germ cell-mediated chimera technology to produce viable Houbara bustard offspring.Embryonic gonadal tissue was dissected from Houbara bustard embryos at eight days post-incubation. Subsequently, Houbara tissue containing gonadal primordial germ cells (gPGCs was injected into White Leghorn chicken (Gallus gallus domesticus embryos, producing 83/138 surviving male chimeric embryos, of which 35 chimeric roosters reached sexual maturity after 5 months. The incorporation and differentiation of Houbara gPGCs in chimeric chicken testis were assessed by PCR with Houbara-specific primers and 31.3% (5/16 gonads collected from the injected chicken embryos showed the presence of donor Houbara cells. A total of 302 semen samples from 34 chimeric roosters were analyzed and eight were confirmed as germline chimeras. Semen samples from these eight roosters were used to artificially inseminate three female Houbara bustards. Subsequently, 45 Houbara eggs were obtained and incubated, two of which were fertile. One egg hatched as a male live born Houbara; the other was female but died before hatching. Genotyping confirmed that the male chick was a pure-line Houbara derived from a chimeric rooster.This study demonstrates for the first time that Houbara gPGCs can migrate, differentiate and eventually give rise to functional sperm in the chimeric chicken testis. This approach may provide a promising tool for propagation and conservation of endangered avian

Prenatal ultrasound and postmortem histologic evaluation of tooth germs: an observational, transversal study.

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Seabra, Mariana; Felino, António; Nogueira, Rosete; Valente, Francisco; Braga, Ana Cristina; Vaz, Paula

2015-05-12

Hypodontia is the most frequent developmental anomaly of the orofacial complex, and its detection in prenatal ultrasound may indicate the presence of congenital malformations, genetic syndromes and chromosomal abnormalities. To date, only a few studies have evaluated the histological relationship of human tooth germs identified by two-dimensional (2D) ultrasonography. In order to analyze whether two-dimensional ultrasonography of tooth germs may be successfully used for identifying genetic syndromes, prenatal ultrasound images of fetal tooth germs obtained from a Portuguese population sample were compared with histological images obtained from fetal autopsies. Observational, descriptive, transversal study. The study protocol followed the ethical principles outlined by the Helsinki Declaration and was approved by the Ethics Committee of the School of Dental Medicine, University of Porto (FMDUP, Porto, Portugal) and of the Centro Hospitalar de Vila Nova de Gaia/Espinho (CHVNG/EPE, Porto, Portugal) as well as by the CGC Genetics Embryofetal Pathology Laboratory. Eighty-five fetuses examined by prenatal ultrasound screening from May 2011 to August 2012 had an indication for autopsy following spontaneous fetal death or medical termination of pregnancy. Of the 85 fetuses, 37 (43.5%) were randomly selected for tooth germ evaluation by routine histopathological analysis. Fetuses who were up to 30 weeks of gestation, and whose histological pieces were not representative of all maxillary tooth germs was excluded. Twenty four fetus between the 13(th) and 30(th) weeks of gestation fulfilled the parameters to autopsy. Twenty four fetuses were submitted to histological evaluation and were determined the exact number, morphology, and mineralization of their tooth germs. All tooth germs were identifiable with ultrasonography as early as the 13(th) week of gestation. Of the fetuses autopsied, 41.7% had hypodontia (29.1% maxillary hypodontia and 20.9% mandibular hypodontia). This

Molecular biology of testicular germ cell tumors.

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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.

Childhood Central Nervous System Germ Cell Tumors Treatment (PDQ®)—Health Professional Version

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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.

Hybrid incompatibilities are affected by dominance and dosage in the haplodiploid wasp Nasonia

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Beukeboom, Leo W.; Koevoets, Tosca; Morales, Hernán E.; Ferber, Steven; van de Zande, Louis

2015-01-01

Study of genome incompatibilities in species hybrids is important for understanding the genetic basis of reproductive isolation and speciation. According to Haldane's rule hybridization affects the heterogametic sex more than the homogametic sex. Several theories have been proposed that attribute asymmetry in hybridization effects to either phenotype (sex) or genotype (heterogamety). Here we investigate the genetic basis of hybrid genome incompatibility in the haplodiploid wasp Nasonia using the powerful features of haploid males and sex reversal. We separately investigate the effects of heterozygosity (ploidy level) and sex by generating sex reversed diploid hybrid males and comparing them to genotypically similar haploid hybrid males and diploid hybrid females. Hybrid effects of sterility were more pronounced than of inviability, and were particularly strong in haploid males, but weak to absent in diploid males and females, indicating a strong ploidy level but no sex specific effect. Molecular markers identified a number of genomic regions associated with hybrid inviability in haploid males that disappeared under diploidy in both hybrid males and females. Hybrid inviability was rescued by dominance effects at some genomic regions, but aggravated or alleviated by dosage effects at other regions, consistent with cytonuclear incompatibilities. Dosage effects underlying Bateson–Dobzhansky–Muller (BDM) incompatibilities need more consideration in explaining Haldane's rule in diploid systems. PMID:25926847

Ovarian mixed germ cell tumor with yolk sac and teratomatous components in a dog.

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Robinson, Nicholas A; Manivel, J Carlos; Olson, Erik J

2013-05-01

Mixed germ cell tumors of the ovary have rarely been reported in veterinary species. A 3-year-old intact female Labrador Retriever dog was presented for lethargy, abdominal distention, and a midabdominal mass. An exploratory laparotomy revealed a large (23 cm in diameter) left ovarian tumor and multiple small (2-3 cm in diameter) pale tan masses on the peritoneum and abdominal surface of the diaphragm. Histological examination of the left ovary revealed a mixed germ cell tumor with a yolk sac component with rare Schiller-Duval bodies and a teratomatous component comprised primarily of neural differentiation. The abdominal metastases were solely comprised of the yolk sac component. The yolk sac component was diffusely immunopositive for cytokeratin with scattered cells reactive for α-fetoprotein and placental alkaline phosphatase. Within the teratomatous component, the neuropil was diffusely immunopositive for S100, neuron-specific enolase, and neurofilaments with a few glial fibrillary acidic protein immunopositive cells. Ovarian germ cell tumors may be pure and consist of only 1 germ cell element or may be mixed and include more than 1 germ cell element, such as teratoma and yolk sac tumor.

When does germ cell loss and fibrosis occur in patients with Klinefelter syndrome?

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Van Saen, D; Vloeberghs, V; Gies, I; Mateizel, I; Sermon, K; De Schepper, Jean; Tournaye, H; Goossens, E

2018-06-01

When does germ cell loss and fibrosis occur in patients with Klinefelter syndrome (KS)? In KS, germ cell loss is not observed in testicular tissue from fetuses in the second semester of pregnancy but present at a prepubertal age when the testicular architecture is still normal, while fibrosis is highly present at an adolescent age. Most KS patients are azoospermic at adult age because of a massive germ cell loss. However, the timing when this germ cell loss starts is not known. It is assumed that germ cell loss increases at puberty. Therefore, testicular sperm extraction (TESE) at an adolescent age has been suggested to increase the chances of sperm retrieval at onset of spermatogenesis. However, recent data indicate that testicular biopsies from peripubertal KS patients contain only a few germ cells. In this study, we give an update on fertility preservation in adolescent KS patients and evaluate whether fertility preservation would be beneficial at prepubertal age. The possibility of retrieving testicular spermatozoa by TESE was evaluated in adolescent and adult KS men. The presence of spermatogonia and the degree of fibrosis were also analysed in testicular biopsies from KS patients at different ages. The patients were divided into four age groups: foetal (n = 5), prepubertal (aged 4-7 years; n = 4), peripubertal (aged 12-16 years; n = 20) and adult (aged 18-41 years; n = 27) KS patients. In peripubertal and adult KS patients, retrieval of spermatozoa was attempted by semen analysis after masturbation, vibrostimulation, electroejaculation or by TESE. MAGE-A4 immunohistochemistry was performed to evaluate the presence of germ cells in testicular biopsies from foetal, prepubertal, peripubertal and adult KS patients. Tissue morphology was evaluated by haematoxylin-periodic acid Schiff (H/PAS) staining. Testicular spermatozoa were collected by TESE in 48.1% of the adult KS patients, while spermatozoa were recovered after TESE in only one peripubertal patient (5

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...

Pluripotency Factors in Embryonic Stem Cells Regulate Differentiation into Germ Layers

OpenAIRE

Thomson, Matt; Liu, Siyuan John; Zou, Ling-Nan; Smith, Zack; Meissner, Alexander; Ramanathan, Sharad

2011-01-01

Cell fate decisions are fundamental for development, but we do not know how transcriptional networks reorganize during the transition from a pluripotent to a differentiated cell state. Here, we asked how mouse embryonic stem cells (ESCs) leave the pluripotent state and choose between germ layer fates. By analyzing the dynamics of the transcriptional circuit that maintains pluripotency, we found that Oct4 and Sox2, proteins that maintain ESC identity, also orchestrate germ layer fate selection...

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

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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

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.

Primordial germ cell biology at the beginning of the XXI century.

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De Felici, Massimo

2009-01-01

At the XIV Workshop on the Development and Function of the Reproductive Organs held at the Congress Centre of the University of Rome Tor Vergata, Monteporzio Catone, Rome, Italy, the introduction to the first session entitled Mammalian primordial germ cells dedicated to the memory of Anne McLaren, was the occasion for a concise review of the state of art of research on the biology of primordial germ cells (PGCs). This great, unforgettable scientist, who died in a car accident in July 2007, dedicated most of her studies to this field over the last 25 years. Topics briefly reviewed in this Meeting Report are: 1) how the germ line is determined; 2) what are the mechanisms underlying PGC migration; 3) to what extent PGC survival, proliferation and differentiation are cell autonomous or environmentally controlled processes and 4) how the potential for totipotency is retained in PGCs.

EMMPRIN (basigin/CD147) is involved in the morphogenesis of tooth germ in mouse molars.

Science.gov (United States)

Xie, Ming; Jiao, Ting; Chen, Yuqin; Xu, Chun; Li, Jing; Jiang, Xinquan; Zhang, Fuqiang

2010-05-01

The pattern of gene expression for extracellular matrix metalloproteinase inducer (EMMPRIN) was revealed in the tooth germ of mouse mandibular molars using quantitative real-time PCR. In situ hybridization and immunohistochemical study demonstrated the characteristic distribution of EMMPRIN in the different stages of tooth germ development. To investigate the functional role played by EMMPRIN in tooth germ development, EMMPRIN siRNA interference approach was carried out in cultured mouse mandibles at embryonic day 11.0 (E11.0). The results showed that EMMPRIN siRNA-treated explants exhibited a marked growth inhibition of tooth germ compared to the control and scrambled siRNA-treated explants. Meanwhile, a significant increase in MT1-MMP mRNA expression and a reduction in MMP-2, MMP-3, MMP-9, MMP-13 and MT2-MMP mRNA expression were observed in the mouse mandibles following EMMPRIN abrogation. The current results indicate that EMMPRIN could thus be involved in the early stage of tooth germ development and morphogenesis, possibly by regulating the expression of MMP genes.

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

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

High production of wheat double haploids via anther culture

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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.

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)

Oxidative stress and male reproductive health

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Robert J Aitken

2014-02-01

Full Text Available One of the major causes of defective sperm function is oxidative stress, which not only disrupts the integrity of sperm DNA but also limits the fertilizing potential of these cells as a result of collateral damage to proteins and lipids in the sperm plasma membrane. The origins of such oxidative stress appear to involve the sperm mitochondria, which have a tendency to generate high levels of superoxide anion as a prelude to entering the intrinsic apoptotic cascade. Unfortunately, these cells have very little capacity to respond to such an attack because they only possess the first enzyme in the base excision repair (BER pathway, 8-oxoguanine glycosylase 1 (OGG1. The latter successfully creates an abasic site, but the spermatozoa cannot process the oxidative lesion further because they lack the downstream proteins (APE1, XRCC1 needed to complete the repair process. It is the responsibility of the oocyte to continue the BER pathway prior to initiation of S-phase of the first mitotic division. If a mistake is made by the oocyte at this stage of development, a mutation will be created that will be represented in every cell in the body. Such mechanisms may explain the increase in childhood cancers and other diseases observed in the offspring of males who have suffered oxidative stress in their germ line as a consequence of age, environmental or lifestyle factors. The high prevalence of oxidative DNA damage in the spermatozoa of male infertility patients may have implications for the health of children conceivedin vitro and serves as a driver for current research into the origins of free radical generation in the germ line.

Oocyte toxicity: female germ-cell loss from radiation and chemical exposures

International Nuclear Information System (INIS)

Dobson, R.L.

1984-01-01

In some mammals, female germ cells are extraordinarily sensitive to killing by exposure to ionizing radiation, especially during development. Immature oocytes, which constitute the lifetime germ-cell pool of the female, have an LD 50 in juvenile mice of only 6 rad (compared with typical LD 50 s of 100-300 rad for most other cell types studied). Essentially, the entire germ-cell supply in female squirrel monkeys is destroyed prenatally by exposure of only 0.7 rad/day. Severe but lesser destruction has been found in other species. However, evidence suggests (though not ruled out for all developmental stages) that unusually high sensitivity probably does not occur in the human female. Germ cells can also be killed by certain chemicals, and similarities exist between chemical and radiation effects. More than 75 compounds have been quantitatively studied in mice, with determination of OTI values (OTI = oocyte toxicity index = mouse LD 50 /oocyte LD 50 ) to measure the degree of preferential oocyte killing. High sensitivity in mice does not mean necessarily high sensitivity in women. Of special interest is the recent discovery that the lethal target in the extremely sensitive mouse immature oocyte is probably the plasma membrane, not DNA. Since mouse data form the main basis from which human genetic hazard (for both radiation and chemicals) is estimated, this has important implications for the determination of genetic risk in women

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

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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.

On the number of founding germ cells in humans

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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.

Conservation of Poultry Germplasm Through Cryopreservation of Primordial Germ Cells (PGCs

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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.

Impact of Coagulase-Negative Staphylococci and Other Germs on Sperm Forms

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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.

Female-to-male sex reversal in mice caused by transgenic overexpression of Dmrt1

DEFF Research Database (Denmark)

Zhao, Liang; Svingen, Terje; Ting Ng, Ee

2015-01-01

for primary sex determination and instead maintains Sertoli cell phenotype in postnatal testes. Here, we report that enforced expression of Dmrt1 in XX mouse fetal gonads using a Wt1-BAC transgene system is sufficient to drive testicular differentiation and male secondary sex development. XX transgenic fetal...... into testicular cell types, including steroidogenic fetal Leydig cells and non-meiotic germ cells. As a consequence, male internal and external reproductive organs developed postnatally, with an absence of female reproductive tissues. These results reveal that Dmrt1 has retained its ability to act as the primary...

Ovarian germ cell tumors with rhabdomyosarcomatous components and later development of growing teratoma syndrome: a case report

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Al-Jumaily Usama

2012-01-01

Full Text Available Abstract Introduction Development of a sarcomatous component in a germ cell tumor is an uncommon phenomenon. Most cases reported have a grim prognosis. Growing teratoma syndrome is also an uncommon phenomenon and occurs in approximately 2% to 7% of non seminomatous germ cell tumors and should be treated surgically. Case presentation We report the case of a 12-year-old Asian girl with an ovarian mixed germ cell tumor containing a rhabdomyosarcomatous component. She was treated with a germ cell tumor chemotherapy regimen and rhabdomyosarcoma-specific chemotherapy. Towards the end of her treatment, she developed a retroperitoneal mass that was increasing in size. It was completely resected, revealing a mature teratoma, consistent with growing teratoma syndrome. She is still in complete remission approximately three years after presentation. Conclusion The presence of rhabdomyosarcoma in a germ cell tumor should be treated by a combined chemotherapy regimen (for germ cell tumor and rhabdomyosarcoma. In addition, development of a mass during or after therapy with normal serum markers should raise the possibility of growing teratoma syndrome that should be treated surgically.

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 ...

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

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

Efficacy of wheat germ oil in modulating radiation-induced heart damage in rats

International Nuclear Information System (INIS)

Said, U.Z.; Azab, Kh.Sh.

2006-01-01

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 beneficial in neutralizing the free oxygen radicals. This study was designed to investigate the cardio-protective efficacy of wheat germ oil, on radiation-induced oxidative damage in rat's heart. Wheat germ oil was supplemented by gavage to rats at a dose of 81 mg/ kg body wt for 10 successive days pre- and 7 successive days post-exposure to 7 Gy (single dose) of whole body gamma irradiation. The dose of wheat germ oil is equivalent to daily human nutritional supplementation quantity. The results revealed that whole body ?-irradiation of rats produced significant alterations in blood cells picture. The erythrocyte, leucocyte, platelet counts and hemoglobin levels decreased after irradiation. Also, radiation-induced biochemical disorders manifested by significant elevation in xanthine oxidase activity (XO) and thiobarbituric acid reactive substances (TBARS) level, with decrease in reduced glutathione (GSH) content in heart tissues, indicating depression in the antioxidant status. Serum lipid profile as total cholesterol, high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and triglycerides levels (TG) were significantly higher than normal control rats. Radiation exposure produced a significant rise in the activities of serum markers for heart damage as creatine phosphokinase (CPK), aspartate aminotransferase (AST) and lactic dehydrogenase (LDH) indicating acute cardiac toxicity. Moreover, the obtained results revealed abnormal electrophoretic pattern of LDH isoenzymes in the 7th day after exposure to gamma rays. Three bands only appear on the agarose film comparing with 4 bands in normal control rats. The rats that received wheat germ oil supplement showed significantly less severe damage and remarkable improvement in all of the measured parameters when compared to

Further characterization of serum alkaline phosphatase from male and female beagle dogs.

Science.gov (United States)

Amacher, D E; Higgins, C V; Schomaker, S J; Clay, R J

1989-01-01

Alkaline phosphatase (AP) from the sera of both male and female beagle dogs was partially purified and then analyzed for the presence of AP isoenzymes having intestinal or osseous characteristics as detected by bromotetramisole inhibition or wheat germ lectin agarose electrophoresis, respectively. The sera from both sexes were similar in regard to the presence of AP isoenzymes with intestinal (16 vs. 20%) or osseous (19 vs. 23%) characteristics, but serum AP from the male had a greater sialic acid content and only the male serum contained a detectable constitutive acidic (pI = 3.4) AP isoenzyme. This was similar to a serum AP isoenzyme previously found elevated in the sera of dogs afflicted with hyperadrenocorticalism or of dogs treated with certain corticosteroids.

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

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.

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 ...

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 ...

Germ Plasm Anchoring Is a Dynamic State that Requires Persistent Trafficking

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Kristina S. Sinsimer

2013-12-01

Full Text Available Localized cytoplasmic determinants packaged as ribonucleoprotein (RNP particles direct embryonic patterning and cell fate specification in a wide range of organisms. Once established, the asymmetric distributions of such RNP particles must be maintained, often over considerable developmental time. A striking example is the Drosophila germ plasm, which contains RNP particles whose localization to the posterior of the egg during oogenesis results in their asymmetric inheritance and segregation of germline from somatic fates in the embryo. Although actin-based anchoring mechanisms have been implicated, high-resolution live imaging revealed persistent trafficking of germ plasm RNP particles at the posterior cortex of the Drosophila oocyte. This motility relies on cortical microtubules, is mediated by kinesin and dynein motors, and requires coordination between the microtubule and actin cytoskeletons. Finally, we show that RNP particle motility is required for long-term germ plasm retention. We propose that anchoring is a dynamic state that renders asymmetries robust to developmental time and environmental perturbations.

Genetic Diversity in Haploid Nicotiana alata Induced by Gamma Irradiation, Salt Tolerance and Detection of These Differences by RAPD

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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.

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

The Nanos3-3'UTR is required for germ cell specific NANOS3 expression in mouse embryos.

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Hitomi Suzuki

Full Text Available BACKGROUND: The regulation of gene expression via a 3' untranslated region (UTR plays essential roles in the discrimination of the germ cell lineage from somatic cells during embryogenesis. This is fundamental to the continuation of a species. Mouse NANOS3 is an essential protein required for the germ cell maintenance and is specifically expressed in these cells. However, the regulatory mechanisms that restrict the expression of this gene in the germ cells is largely unknown at present. METHODOLOGY/PRINCIPAL FINDINGS: In our current study, we show that differences in the stability of Nanos3 mRNA between germ cells and somatic cells is brought about in a 3'UTR-dependent manner in mouse embryos. Although Nanos3 is transcribed in both cell lineages, it is efficiently translated only in the germ lineage. We also find that the translational suppression of NANOS3 in somatic cells is caused by a 3'UTR-mediated mRNA destabilizing mechanism. Surprisingly, even when under the control of the CAG promoter which induces strong ubiquitous transcription in both germ cells and somatic cells, the addition of the Nanos3-3'UTR sequence to the coding region of exogenous gene was effective in restricting protein expression in germ cells. CONCLUSIONS/SIGNIFICANCE: Our current study thus suggests that Nanos3-3'UTR has an essential role in translational control in the mouse embryo.

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.

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

Effects of postnatal administration of diethylstilbestrol on puberty and thyroid function in male rats.

Science.gov (United States)

Shin, Jae-Ho; Kim, Tae Sung; Kang, Il Hyun; Kang, Tae Seok; Moon, Hyun Ju; Han, Soon-Young

2009-10-01

To examine the effects of diethylstilbestrol (DES) on male pubertal development and thyroid function, juvenile male Sprague-Dawley rats were given DES daily by oral intubation at doses of 10, 20 and 40 microg/kg/day from postnatal day 33 for 20 days. Prepuce separation was significantly delayed at the dose of 20 microg/kg/day and above in the DES-treated rats. DES treatment induced a significant reduction in the weights of testes, epididymides, the ventral prostate, seminal vesicles plus coagulating glands and fluid, levator ani bulbocavernosus muscles, Cowper's glands and the glans penis. The weights of the liver and adrenals increased in the DES-treated animals. DES caused a dose-dependent reduction in germ cells; in particular the spermatids were mainly affected. The serum levels of testosterone and luteinizing hormone were significantly reduced in the DES-treated groups, but that of estradiol decreased. No differences were observed in the serum thyroxine levels of the control and DES-treated groups. In microscopic observation of the DES-treated animals, degeneration of germ cells and tubular atrophy in the testis were noted, but there were no microscopic changes in the thyroid. These results indicate that DES affected the pubertal development of juvenile male rats and that its mode of action may be related to alterations in hormone levels.

Unusual Father-to-Daughter Transmission of Incontinentia Pigmenti Due to Mosaicism in IP Males.

Science.gov (United States)

Fusco, Francesca; Conte, Matilde Immacolata; Diociaiuti, Andrea; Bigoni, Stefania; Branda, Maria Francesca; Ferlini, Alessandra; El Hachem, Maya; Ursini, Matilde Valeria

2017-09-01

Incontinentia pigmenti (IP; Online Mendelian Inheritance in Man catalog #308300) is an X-linked dominant ectodermal disorder caused by mutations of the inhibitor of κ polypeptide gene enchancer in B cells, kinase γ ( IKBKG )/ nuclear factor κB, essential modulator ( NEMO ) gene. Hemizygous IKBKG/NEMO loss-of-function (LoF) mutations are lethal in males, thus patients are female, and the disease is always transmitted from an IP-affected mother to her daughter. We present 2 families with father-to-daughter transmission of IP and provide for the first time molecular evidence that the combination of somatic and germ-line mosaicism for IKBKG/NEMO loss of function mutations in IP males resulted in the transmission of the disease to a female child. We searched for the IKBKG/NEMO mutant allele in blood, urine, skin, and sperm DNA and found that the 2 fathers were somatic and germ-line mosaics for the p.Gln132×mutation or the exon 4-10 deletion of IKBKG/NEMO , respectively. The highest level of IKBKG/NEMO mutant cells was detected in the sperm, which might explain the recurrence of the disease. We therefore recommend careful clinical evaluation in IP male cases and the genetic investigation in sperm DNA to ensure correct genetic counseling and prevent the risk of paternal transmission of IP. Copyright © 2017 by the American Academy of Pediatrics.

Systems Toxicology of Male Reproductive Development ...

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 reproductive developmental defects. The present study established the links between environmental chemicals, molecular targets, and adverse outcomes using U.S. EPA animal study (ToxRefDB) and high-throughput screening (ToxCast) databases. This systems-based approach revealed a phenotypic hierarchy across 63 chemicals and a pleiotropic in vitro bioactivity profile. Although estrogenic and anti-androgenic activities have been extensively studied in male reproductive developmental toxicity, the present study showed these receptor targets to be only a subset of the potential landscape of molecular targets. A variety of chemical (e.g. phthalates, conazoles, carbamates, and phenol compounds) and bioactivity (e.g. nuclear receptors, vascular remodeling proteins, and cytochrome-P450 reductases) clusters further suggested multiple pathways leading to the adverse outcomes. This points to the need for multi-scale systems models to predict whether the occurrence of one adverse outcome may predict the risk of another. Imbalances in androgen and estrogen signaling have been a general focus in male reproductive toxicology research. While a number of recent studies have demonstrated that both hormonal

Metabolism of UC-labelled urea in conventional, germ-free and mono-associated rats

Energy Technology Data Exchange (ETDEWEB)

Juhr, N.C.; Franke, J.

1987-01-01

This report deals with the utilization of UC-labelled urea in conventional, defined associated and germ-free rats. With conventional animals 71.44% of the administered UC dose can be demonstrated in the exhaled air, 0.47% in organs and 27.35% in the urine. 1.04% was found in the intestinal and fecal contents. Animals mono-associated with Proteus mirabilis have nearly the same utilization rate (59.15, 0.34, 35.98, 2% resp.). In germ-free animals 1.21% of the activity appeared in the exhaled air and showed a small part of non-enzymatic hydrolysis of urea. The excretion of 97.70% in the urine shows that urea is absorbed from the intestine in germ-free animals.

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

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

THE MODERN THEORY AND TECHNOLOGY OF PRODUCTION, PROCESSING AND USE OF THE PRODUCTS OF COMPLEX PROCESSING OF WHEAT GERM

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N. S. Rodionova

2014-01-01

Full Text Available Summary. The data and methods for the preparation of deep processing of wheat germ and their impact on the physical and chemical properties of the final products. It was found that for use in food technology is preferable to use a method is-cold-pressed wheat germ, under which the processed products do not present a residual amount of solvents and other non-food components. Given food and biological characteristics of wheat germ and products deep processing, it was found that they contain vitamin E, A, D, vitamin group В, more than 20 macro- and microelements. Methods of extracting oil from different types raw materials. Analyzed the functional role of ω-6 and ω -3 fatty acids for the human body and ways to maintain balance. A review of plant oils, the prospects of its use to create food systems balanced composition of fatty acids. It was found that the ratio of ω-6 and ω -3 fatty acids in wheat germ oil does not meet the recommended therefore to establish the necessary balance it is preferable to mix amaranth oil and pumpkin. Classified the factors affecting the quality parameters of wheat germ stored, evaluated the role of the enzyme complex during storage of wheat germ and their products deep processing. It was found that a significant effect on the damage of wheat germ has a dual action of lipase, lipoxygenase and catalase. Given the storage and stabilization of wheat germ, shows the potential use of stabilizers to increase the shelf life of wheat germ. As stabilizers, preference is given to compositions of organic acids: ascorbic, succinic and fumaric. It is proved that the composition of organic acids suppress the activity of lipase and lipoxygenase catalase by wheatgerm type noncompetitive inhibition. A review of the technologies used wheat germ and products of their complex processing in medical, cosmetic, feed and food industry. Evaluated the potential application of wheat germ and products deep processing industry of functional

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.

Profiling of androgen response in rainbow trout pubertal testis: relevance to male gonad development and spermatogenesis.

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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.

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

Research of Wheat Germ Foaming Capacity in Dairy Ice-Cream Composition

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V.V. Martich

2013-09-01

Full Text Available Surface activity of grain component in model systems and in the milk ice cream is investigated. It is found that increase of wheat germ comtent in model systems and mixtures leads to a corresponding decrease in surface tension in the presence of surface-active plant protein. The expediency of previous frying and shredding of plant material to improve its foaming ability in the milk mixtures is proved. The need of wheat germ hydration before its use to improve functional and technological properties in the ice cream is confirmed.

Novel Soy Germ Pasta Enriched in Isoflavones Ameliorates Gastroparesis in Type 2 Diabetes

Science.gov (United States)

Setchell, Kenneth D.R.; Nardi, Elisabetta; Battezzati, Pier-Maria; Asciutti, Stefania; Castellani, Danilo; Perriello, Gabriele; Clerici, Carlo

2013-01-01

OBJECTIVE To determine the effect of soy germ pasta enriched in biologically active isoflavone aglycons on gastric emptying in type 2 diabetic patients with gastroparesis. RESEARCH DESIGN AND METHODS This randomized double-blind, placebo-controlled study compared soy germ pasta with conventional pasta for effects on gastric emptying. Patients (n = 10) with delayed gastric emptying consumed one serving per day of each pasta for 8 weeks, with a 4-week washout. Gastric emptying time (t1/2) was measured using the [13C]octanoic acid breath test at baseline and after each period, and blood glucose and insulin concentrations were determined after oral glucose load. RESULTS Soy germ pasta significantly accelerated the t1/2 in these patients (161.2 ± 17.5 min at baseline vs. 112.6 ± 11.2 min after treatment, P = 0.009). Such change differed significantly (P = 0.009) from that for conventional pasta (153.6 ± 24.2 vs. 156.2 ± 27.4 min), without affecting glucose or insulin concentrations. CONCLUSIONS These findings suggest that soy germ pasta may offer a simple dietary approach to managing diabetic gastropathy. PMID:23835688

In utero and transgeneration effects and biological defence mechanism in mice

International Nuclear Information System (INIS)

Normura, T.

1992-01-01

Multicellular animals are composed of 2 types of cells; cells of the germ line, from which next generation of gametes will be derived, and the somatic cells, which form the rest of the body and leave no progeny. In a sense, somatic cells exist only to help the germ line cells survive and propagate. During development of mammals, 2 haploid cells (gametes), one large and non-motile (ovum) and the other small and motile (sperm) fuse and then diploid cells proliferate and diversify to form a complex multicellular organism in utero. During the long course of germ line and embryonic development, there are extraordinary radiation (also chemicals)-sensitive phases, some of which must be very important for animals to defense their species from radiation and chemical hazards in the environment by replacing damaged cells with un-damaged or normal totipotent reserve cells. (author). 17 refs., 5 figs

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...

Germs of local automorphisms of real analytic CR structures and analytic dependence on the k-jets

OpenAIRE

ZAITSEV, DMITRI

1997-01-01

PUBLISHED The topic of the paper is the study of germs of local holomorphisms f between Cn and Cn ? such that f(M) #26; M? and df(TcM) = TcM? for M #26; Cn and M? #26; Cn ? generic real-analytic CR submanifolds of arbitrary codimensions. It is proved that for M minimal and M? finitely nondegenerate, such germs depend analytically on their jets. As a corollary, an analytic structure on the set of all germs of this type is obtained.

Wheat Germ Oil Attenuates Gamma Radiation- Induced Skeletal Muscles Damage in Rats

International Nuclear Information System (INIS)

Said, U.Z.; Saada, H.N.; Shedid, Sh.M.; Mahdy, E.M.E.; Shousha, W.Gh.

2008-01-01

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 beneficial in neutralizing the free oxygen radicals. The present study was designed to investigate the efficacy of wheat germ oil, on radiation-induced oxidative damage in rats skeletal muscle. Wheat germ oil was supplemented orally via gavages to rats at a dose of 54 mg/ kg body weight/day for 14 successive days pre- and 7 post-exposure to 5 Gy (one shot dose) of whole body gamma irradiation. Animals were sacrificed 7, 14 and 21 days post radiation exposure. The results revealed that whole body gamma-irradiation of rats induces oxidative stress in skeletal muscles obvious by significant elevation in the level of thiobarbituric acid reactive substances (TBARS) associated with significant decreases in the content of reduced glutathione (GSE1), as well as decreases in superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities. Irradiated rats showed, also, significant decreases in creatine phosphokinase (CPK), glutamate dehydrogenase (GDH) and glucose-6-phosphate dehydrogenase (G-6-PD) activities. Furthermore, total iron, total copper and total calcium levels were significantly increased in skeletal muscles of irradiated rats group compared to control group. Wheat germ oil treated-irradiated rats showed significantly less sever damage and remarkable improvement in all the measured parameters, compared to irradiated rats. It could be concluded that wheat germ oil by attenuating radiation induced oxidative stress might play a role in maintaining skeletal muscle integrity

Spondyloepiphseal dysplasia congenita in siblings born to unaffected parents: ? germ line mosaicism

Energy Technology Data Exchange (ETDEWEB)

Mulla, W.; McDonald-McGinn, D.; Zackai, E. [Univ. of Pennsylvania School of Medicine, Philadelphia, PA (United States)] [and others

1994-09-01

Germ line mosaicism has been used to explain the birth of more than one child affected with a dominantly inherited disorder born to unaffected parents. Furthermore, it has been confirmed clinically in families where recurrence in siblings was originally thought to be autosomal recessive, but were affected individuals have reproduced affected offspring. Firm evidence of germ line mosaicism using mutation analysis by molecular methods exists for some autosomal disorders. We present two siblings with spondyloepipheseal dysplasia congenita (SEDC) born to unaffected parents. This suggests the presence of germ line mosaicism in this entity. Patient 1 was born at 32 weeks gestation to a G1P1 Puerto Rican mother. The pregnancy was complicated by polyhydramnios. The neonate, a short-limbed dwarf, died at 15 hours of age from respiratory distress and a compromised thoracic cavity. Patient 2, the sibling of patient 1 was born at 37 weeks gestation after a pregnancy complicated by polyhydramnios and prenatal ultrasound diagnosis of short-limbed dwarfism. The diagnosis of SEDC was made and, after review of the sibling`s postmortem X-rays, it was felt that she was similarly affected. The family history reveals no history of dwarfism or consanguinity. The SEDC is described as an autosomal dominant form of dwarfism with variable presentation including some cases that have been lethal in the neonatal period. SEDC is now believed to represent a family of collagen II mutations. Sporadic cases that have arisen in families with no history have been ascribed to new heterozygous mutations. Other families in which SEDC and SEMD recurred without a family history most likely represent germ line mosaicism. In these cases molecular studies should be pursued to document a collagen II mutation. We believe that germ line mosaicism is the most plausible explanation for recurrence in our family.

Serum inhibin B levels during male childhood and puberty

DEFF Research Database (Denmark)

Andersson, A M; Skakkebaek, N E

2001-01-01

Inhibin B is a testicular peptide hormone that regulates FSH secretion in a negative feedback loop. In males serum levels of inhibin B are detectable throughout life with prominent changes in the first year of life and during puberty. Serum inhibin B is normally detectable throughout childhood...... normal or near-normal levels are seen in cryptorchidism and disorders with preserved Sertoli cell function in spite of absence of germ cells or impaired androgen biosynthesis or action. During puberty a developmental change in the regulation of serum inhibin B occurs. In contrast to childhood inhibin B...