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Sample records for chromosome substitution lines

  1. Chromosomal location of genes encoding for resistance to septoria tritici blotch (Mycosphaerella graminicola) in substitution lines of wheat

    NARCIS (Netherlands)

    Simón, M.R.; Worland, A.J.; Struik, P.C.

    2005-01-01

    Chromosomal location of resistance to Mycosphaerella graminicola was studied in substitution lines of resistant Triticum genotypes into the (susceptible) cultivar Chinese Spring (T. aestivum). (Moderately) resistant genotypes for which substitution lines were available were tested in a first screeni

  2. Development of Chromosomal Segment Substitution Lines from a Backcross Recombinant Inbred Population of Interspecific Rice Cross

    Institute of Scientific and Technical Information of China (English)

    CHEN Jie; Hafeez Ur Rahman BUGHIO; CHEN Da-zhou; LIU Guang-jie; ZHENG Kang-le; ZHUANG Jie-yun

    2006-01-01

    A backcross recombinant inbred line population consisting of 202 lines was developed from Xieqingzao B//Xieqingzao B Dongxiang wild rice. The population was assayed with DNA markers and phenotyped on planthopper resistance and yield traits. A linkage map consisting of 119 DNA markers and spanned for 1188 cM over the 12 rice chromosomes was constructed. Thirty-two chromosomal segment substitution lines were selected based on the percentage of Xieqingzao B allele at marker loci. These lines are of great potential for gene mapping and alien gene introgression.

  3. Molecular confirmation of Gossypium hirsutum chromosome substitution lines

    Science.gov (United States)

    The primary gene pool for tetraploid cotton species includes G. hirsutum L., as well as the other four 2n=52 species of Gossypium (G. barbadense, G. mustellinum, G. tomentosum and G. darwinii). To help overcome barriers to effective introgression, we have developed a number of alien chromosome subst...

  4. Exploring the power of rice (O. sativa x O. rufipogon) chromosome segment substitution line libraries

    Science.gov (United States)

    Transgressive variation was reported as an increase in grain yield for several rice (Oryza sativa x O. rufipogon) advanced backcross mapping populations. The objective of this study was to develop chromosome segment substitution line (CSSL) libraries to further dissect the reported transgressive var...

  5. Chromosome Specific Substitution Lines of Aegilops geniculata Alter Parameters of Bread Making Quality of Wheat

    Science.gov (United States)

    Tsujimoto, Hisashi; Gupta, Raj Kumar; Kumar, Aman; Kaur, Navneet; Kumar, Rohit; Chunduri, Venkatesh; Sharma, Nand Kishor; Chawla, Meenakshi; Sharma, Saloni; Mundey, Jaspreet Kaur

    2016-01-01

    Wheat cultivars with wide introgression have strongly impacted global wheat production. Aegilops geniculata (MgUg) is an important wild relative with several useful traits that can be exploited for wheat improvement. Screening of Ae. geniculata addition lines indicated a negative effect of 1Ug and the positive effect of 1Mg chromosome on wheat dough strength. Negative effect of 1Ug is probably associated with variation in number and position of the tripeptide repeat motif in the high molecular weight glutenin (HMW-G) gene. To utilize the positive potential of 1Mg chromosome, three disomic substitution lines (DSLs) 1Mg(1A), 1Mg(1B) and 1Mg(1D) were created. These lines were characterized for morphological, cytogenetic properties and biochemical signatures using FISH, 1D-, 2D-PAGE and RP-HPLC. Contribution of wheat 1A, 1B and 1D chromosomes towards dough mixing and baking parameters, chapatti quality, Fe/Zn content and glume color were identified. Observed order of variation in the dough mixing and baking parameters {1Mg(1D) ≤wheat ≤1Mg(1B) ≤1Mg(1A)} indicated that chromosome specific introgression is desirable for best utilization of wild species’ potential. PMID:27755540

  6. Cotton chromosome substitution lines crossed with cultivars: genetic model evaluation and seed trait analyses.

    Science.gov (United States)

    Wu, Jixiang; McCarty, Jack C; Jenkins, Johnie N

    2010-05-01

    Seed from upland cotton, Gossypium hirsutum L., provides a desirable and important nutrition profile. In this study, several seed traits (protein content, oil content, seed hull fiber content, seed index, seed volume, embryo percentage) for F(3) hybrids of 13 cotton chromosome substitution lines crossed with five elite cultivars over four environments were evaluated. Oil and protein were expressed both as percentage of total seed weight and as an index which is the grams of product/100 seeds. An additive and dominance (AD) genetic model with cytoplasmic effects was designed, assessed by simulations, and employed to analyze these seed traits. Simulated results showed that this model was sufficient for analyzing the data structure with F(3) and parents in multiple environments without replications. Significant cytoplasmic effects were detected for seed oil content, oil index, seed index, seed volume, and seed embryo percentage. Additive effects were significant for protein content, fiber content, protein index, oil index, fiber index, seed index, seed volume, and embryo percentage. Dominance effects were significant for oil content, oil index, seed index, and seed volume. Cytoplasmic and additive effects for parents and dominance effects in homozygous and heterozygous forms were predicted. Favorable genetic effects were predicted in this study and the results provided evidence that these seed traits can be genetically improved. In addition, chromosome associations with AD effects were detected and discussed in this study.

  7. Identification of Quantitative Trait Loci for Rice Quality in a Population of Chromosome Segment Substitution Lines

    Institute of Scientific and Technical Information of China (English)

    Wei Hao; MeiZhen Zhu; JiPing Gao; ShiYong Sun; HongXuan Lin

    2009-01-01

    The demand for high quality rice represents a major issue in rice production. The primary components of rice grain quality include appearance, eating, cooking, physico-chemical, milling and nutritional qualities. Most of these traits are complex and controlled by quantitative trait loci (QTLs), so the genetic characterization of these traits is more difficult than that of traits controlled by a single gene. The detection and genetic identification of QTLs can provide insights into the genetic mechanisms underlying quality traits. Chromosome segment substitution lines (CSSLs) are effective tools used in mapping QTLs. In this study, we constructed 154 CSSLs from backcross progeny (BC3F2) derived from a cross between 'Koshihikari' (an Oryza sativa L. Ssp. Japonica variety) as the recurrent parent and 'Nona Bokra' (an O. Sativa L. Ssp. Indica variety) as the donor parent. In this process, we carried out marker-assisted selection by using 102 cleaved amplified polymorphic sequence and simple sequence repeat markers covering most of the rice genome. Finally, this set of CSSLs was used to identify QTLs for rice quality traits. Ten QTLs for rice appearance quality traits were detected and eight QTLs concerned physico-chemical traits. These results supply the foundation for further genetic studies and breeding for the improvement of grain quality.

  8. Fructan synthesis, accumulation and polymer traits. I. Festulolium chromosome substitution lines

    Directory of Open Access Journals (Sweden)

    Joe A Gallagher

    2015-07-01

    Full Text Available The fructans found as storage carbohydrates in temperate forage grasses have a physiological role in regrowth and stress tolerance. They are also important for the nutritional value of fresh and preserved livestock feeds, and are potentially useful as feedstocks for biorefining. Seasonal variation in fructan content and the capacity for de novo fructan synthesis have been examined in a Festulolium monosomic substitution line family to investigate variation in the polymers produced by grasses in the ryegrass-fescue complex. There were significant differences between ryegrass and fescue. Fescue had low polymeric fructan content and a high oligomer/polymer ratio; synthesis of polymers longer than degree of polymerisation 6 (DP6 from oligomers was slow. However, extension of polymer length from DP10/DP20 upwards appeared to occur relatively freely, and, unlike ryegrass, fescue had a relatively even spread of polymer chain lengths above DP20. This included the presence of some very large polymers. Additionally fescue retained high concentrations of fructan, both polymeric and oligomeric, during conditions of low source/high sink demand. There were indications that major genes involved in the control of some of these traits might be located on fescue chromosome 3 opening the possibility to develop grasses optimised for specific applications.

  9. Analysis of root-knot nematode and fusarium wilt disease resistance in cotton (Gossypium spp.) using chromosome substitution lines from two alien species

    Science.gov (United States)

    To Identify a new germplasm resource, and to validate chromosomal regions and favorable alleles associated with nematode and fungal disease resistance traits, a series of interspecific cotton (Gossypium spp.) chromosome substitution (CS) lines were used in this study. The CS lines were developed in ...

  10. Genetic compensation abilities of Aegilops speltoides chromosomes for homoeologous B-genome chromosomes of polyploid wheat in disomic S(B) chromosome substitution lines

    Science.gov (United States)

    The S genome of Aegilops speltoides is closely related to the B and G genomes of polyploid wheats. However, little work has been reported on the genetic relationships between the S-genome and B-genome chromosomes of polyploid wheat. Here we report the isolation of a set of disomic substitutions (DS)...

  11. Detection of QTL for Cold Tolerance at Bud Bursting Stage Using Chromosome Segment Substitution Lines in Rice (Oryza sativa)

    Institute of Scientific and Technical Information of China (English)

    LIN Jing; WANG Yan-ping; WANG Cai-lin; ZHU Wen-yin; ZHANG Ya-dong; ZHU Zhen; ZHAO Ling; CHEN Tao; ZHAO Qing-yong; ZHOU Li-hui; FANG Xian-wen

    2011-01-01

    The cold tolerance at the bud bursting stage (CTB) was evaluated at 5℃ by using a set of 95 chromosome segment substitution lines (CSSLs) derived from an indica rice 9311 and a japonica rice Nipponbare with a genetic background of 9311.The result showed that six CSSLs had slightly stronger effect on CTB than 9311.Total four quantitative trait loci (QTLs) for CTB were preliminary mapped on chromosomes 5 and 7 by substitution mapping.qCTB-5-1,qCTB-5-2 and qCTB-5-3 were mapped in the region of RM267-RM1237,RM2422-RM6054 and RM3321-RM1054,which were 21.3 cM,27.4 cM and 12.7 cM in genetic distance on rice chromosome 5,respectively.qCTB-7 was mapped in a 6.8-cM region of RM11-RM2752 on rice chromosome 7.

  12. Construction of chromosome segment substitution lines enables QTL mapping for flowering and morphological traits in Brassica rapa

    Directory of Open Access Journals (Sweden)

    Xiaonan eLi

    2015-06-01

    Full Text Available Chromosome segment substitution lines (CSSLs represent a powerful method for precise quantitative trait loci (QTL detection of complex agronomical traits in plants. In this study, we used a marker-assisted backcrossing strategy to develop a population consisting of 63 CSSLs, derived from backcrossing of the F1 generated from a cross between two Brassica rapa subspecies: ‘Chiifu’ (ssp. pekinensis, the Brassica A genome-represented line used as the donor, and ‘49caixin’ (ssp. parachinensis, a non-heading cultivar used as the recipient. The 63 CSSLs covered 87.95% of the B. rapa genome. Among them, 39 lines carried a single segment; 15 lines, two segments; and nine lines, three or more segments of the donor parent chromosomes. To verify the potential advantage of these CSSL lines, we used them to locate QTL for six morphology-related traits. A total of 58 QTL were located on eight chromosomes for all six traits: 17 for flowering time, 14 each for bolting time and plant height, 6 for plant diameter, 2 for leaf width, and 5 for flowering stalk diameter. Co-localized QTL were mainly distributed on eight genomic regions in A01, A02, A05, A06, A08, A09, and A10, present in the corresponding CSSLs. Moreover, new chromosomal fragments that harbored QTL were identified using the findings of previous studies. The CSSL population constructed in our study paves the way for fine mapping and cloning of candidate genes involved in late bolting, flowering, and plant architecture-related traits in B. rapa. Furthermore, it has great potential for future marker-aided gene/QTL pyramiding of other interesting traits in B. rapa breeding.

  13. Genetic mapping of major-effect seed dormancy quantitative trait loci on chromosome 2B using recombinant substitution lines in tetraploid wheat

    Science.gov (United States)

    Durum wheat cultivars can benefit from having some level of seed dormancy to help reduce seed damage and lower grain quality caused by pre-harvest sprouting (PHS) occurring during wet harvesting conditions. Previously a single chromosome substitution line carrying chromosome 2B of wild emmer in the...

  14. Evaluation of Agronomic Traits in Chromosome Segment Substitution Lines of KDML105 Containing Drought Tolerance QTL under Drought Stress

    Institute of Scientific and Technical Information of China (English)

    Vaiphot KANJOO; Kanchana PUNYAWAEW; Jonaliza L. SIANGLIW; Suwat JEARAKONGMAN; Apichart VANAVICHIT; Theerayut TOOJINDA

    2012-01-01

    Drought is a major abiotic constraint to rice production in rainfed lowland and insufficiently irrigated areas.The improvement of drought tolerant varieties is one of the strategies to reduce the negative effects of drought.Quantitative trait loci (QTLs) for primary and secondary traits related to drought toleranco (DT) on chromosomes 1,3,4,8 and 9 that determined from double haploid lines derived from a cross between CT9993 and IR62266 were introgressed and dissected into small pieces in the genetic background of Khao Dawk Mali 105 (KDML105) to develop chromosome segment substitution line (CSSL) population.The CSSLs were evaluated at the reproductive stage for their agronomic performance and yield components under drought stress,and results were compared with irrigated condition.The flowering of CSSL lines was 6 to 7 d earlier than KDML105.The mean values of grain yields in the CSSLs were higher than KDML105 under drought and irrigated conditions.At irrigated condition,the grain yields of introgression lines carrying DT-QTLs from chromosomes 4 and 8 were higher than that of KDML105,whereas other traits showed little difference with KDML105.Analysis indicated that grain yield has positive correlation with plant height,tiller and panicle number per plant,and total grain weight per plant under drought stress while negatively correlated with days to flowering.As mentioned above,CSSLs showing good adaptation under drought stress can be used as genetic materials to improve drought tolerance in Thai rainfed lowland rice breeding program,and as materials to dissect genes underlying drought tolerance.

  15. QTL Mapping for Rice RVA Properties Using High-Throughput Re-sequenced Chromosome Segment Substitution Lines

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chang-quan; HU Bing; ZHU Kong-zhi; ZHANG Hua; LENG Ya-lin; TANG Shu-zhu; GU Ming-hong; LIU Qiao-quan

    2013-01-01

    The rapid visco analyser (RVA) profile is an important factor for evaluation of the cooking and eating quality of rice. To improve rice quality, the identification of new quantitative trait loci (QTLs) for RVA profiling is of great significance. We used a japonica rice cultivar Nipponbare as the recipient and indica rice 9311 as the donor to develop a population containing 38 chromosome segment substitution lines (CSSLs) genotyped by a high-throughput re-sequencing strategy. In this study, the population and the parent lines, which contained similar apparent amylose contents, were used to map the QTLs of RVA properties including peak paste viscosity (PKV), hot paste viscosity (HPV), cool paste viscosity (CPV), breakdown viscosity (BKV), setback viscosity (SBV), consistency viscosity (CSV), peak time (PeT) and pasting temperature (PaT). QTL analysis was carried out using one-way analysis of variance and Dunnett’s test, and stable QTLs were identified over two years and under two environments. We identified 10 stable QTLs:qPKV2-1, qSBV2-1;qPKV5-1, qHPV5-1, qCPV5-1;qPKV7-1, qHPV7-1, qCPV7-1, qSBV7-1;and qPKV8-1 on chromosomes 2, 5, 7 and 8, respectively, with contributions ranging from-95.6%to 47.1%. Besides, there was pleiotropy in the QTLs on chromosomes 2, 5 and 7.

  16. Analysis of root-knot nematode and fusarium wilt disease resistance in cotton (Gossypium spp.) using chromosome substitution lines from two alien species.

    Science.gov (United States)

    Ulloa, M; Wang, C; Saha, S; Hutmacher, R B; Stelly, D M; Jenkins, J N; Burke, J; Roberts, P A

    2016-04-01

    Chromosome substitution (CS) lines in plants are a powerful genetic resource for analyzing the contribution of chromosome segments to phenotypic variance. In this study, a series of interspecific cotton (Gossypium spp.) CS lines were used to identify a new germplasm resource, and to validate chromosomal regions and favorable alleles associated with nematode or fungal disease resistance traits. The CS lines were developed in the G. hirsutum L. TM-1 background with chromosome or chromosome segment substitutions from G. barbadense L. Pima 3-79 or G. tomentosum. Root-knot nematode (Meloidogyne incognita) and fusarium wilt (Fusarium oxysporum f. sp. vasinfectum) (races 1 and 4) resistance alleles and quantitative trait loci (QTL) previously placed on cotton chromosomes using SSR markers in two interspecific recombinant inbred line populations were chosen for testing. Phenotypic responses of increased resistance or susceptibility in controlled inoculation and infested field assays confirmed the resistance QTLs, based on substitution with the positive or negative allele for resistance. Lines CS-B22Lo, CS-B04, and CS-B18 showed high resistance to nematode root-galling, confirming QTLs on chromosomes 4 and 22 (long arm) with resistance alleles from Pima 3-79. Line CS-B16 had less fusarium race 1-induced vascular root staining and higher percent survival than the TM-1 parent, confirming a major resistance QTL on chromosome 16. Lines CS-B(17-11) and CS-B17 had high fusarium race 4 vascular symptoms and low survival due to susceptible alleles introgressed from Pima 3-79, confirming the localization on chromosome 17 of an identified QTL with resistance alleles from TM1 and other resistant lines. Analyses validated regions on chromosomes 11, 16, and 17 harboring nematode and fusarium wilt resistance genes and demonstrated the value of CS lines as both a germplasm resource for breeding programs and as a powerful genetic analysis tool for determining QTL effects for disease

  17. [Effect of rye chromosomes on features of androgenesis in wheat-rye substituted lines of Triticum aestivum L. sort Saratovskaya 29/Secale cerale L. sort Onokhoiskaia and Triticale].

    Science.gov (United States)

    Dobrovolskaia, O B; Pershina, L A; Kravtsova, L A; Silkova, O G; Shchapova, A I

    2001-05-01

    The characteristic features of androgenesis in six wheat-rye substitution lines Triticum aestivum L. (cv. Saratovskaya 29)/Secale cereale L. (cv. Onokhoiskaya) and triticale (2n = 56) using anther culture at different concentrations of 2,4-D in the growth medium were studied. Under variable cultivation conditions, the significant effect of genotypic diversity on the variability of such androgenesis parameters as the frequency of productive anthers, the frequency of embryoid formation, and the frequency of total regenerated plantlets, was shown. It was demonstrated that chromosomes 1R, 3R, and 7R stimulated the formation of androgenous embryoids, while chromosome 5R produced an opposite effect. In triticale and substitution lines, the regeneration ability of androgenous embryoids induced by elevated 2,4-D concentrations was inhibited. Chromosome 1R of the Onokhoiskaya cultivar was suggested to contain genes suppressing regeneration of green plantlets, while chromosome 3R, conversely, stimulated their formation. Chromosomes 1R, 2R, 3R, and 7R of the Onokhoiskaya cultivar did not inhibit the spontaneous formation of androgenous hexaploids in the substitution lines.

  18. Molecular, physicochemical and rheological characteristics of introgressive Triticale/Triticum monococcum ssp. monococcum lines with wheat 1D/1A chromosome substitution.

    Science.gov (United States)

    Salmanowicz, Bolesław P; Langner, Monika; Wiśniewska, Halina; Apolinarska, Barbara; Kwiatek, Michał; Błaszczyk, Lidia

    2013-07-26

    Three sets of hexaploid introgressive triticale lines, with Triticum monococcum ssp. monococcum (cultivated einkorn wheat) genes and a bread wheat chromosome 1D substituted for chromosome 1A, and one set of secondary triticale lines were evaluated for grain and flour physicochemical and dough rheological characteristics in two generations (F7 and F8). Genomic in situ hybridization (GISH) and fluorescence in situ hybridization (FISH) confirmed the 1D/1A chromosome substitution. The presence or absence of einkorn high-molecular-weight (HMW) glutenin subunits and the wheat Glu-D1d locus encoding the 5 + 10 subunits was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), capillary zone electrophoresis, and allele-specific molecular markers. Significant differences were found among physicochemical properties (with the exception of the Hagberg falling number) of all introgressive Triticale/T. monococcum lines and the secondary triticale lines. The wheat 1D/1A chromosome substitution also affected these properties. The results showed that in all introgressive triticale lines, the protein and gluten content, Zeleny sedimentation value, and water absorption capacity, were increased. The rheological parameters estimated using micro-farinograph, reomixer, and Kieffer dough extensibility systems also showed an appreciable increase in dough-mixing properties, maximum resistance to extension (Rmax), and dough extensibility. Introgressive Triticale/T. monococcum lines with 5 + 10 subunits have particularly favorable rheological parameters. The results obtained in this study suggest that the cultivated einkorn genome Am, in the context of hexaploid secondary triticale lines and with a wheat 1D/1A substitution, has the potential to improve gluten polymer interactions and be a valuable genetic resource for triticale quality improvement.

  19. Molecular, Physicochemical and Rheological Characteristics of Introgressive Triticale/Triticum monococcum ssp. monococcum Lines with Wheat 1D/1A Chromosome Substitution

    Directory of Open Access Journals (Sweden)

    Lidia Błaszczyk

    2013-07-01

    Full Text Available Three sets of hexaploid introgressive triticale lines, with Triticum monococcum ssp. monococcum (cultivated einkorn wheat genes and a bread wheat chromosome 1D substituted for chromosome 1A, and one set of secondary triticale lines were evaluated for grain and flour physicochemical and dough rheological characteristics in two generations (F7 and F8. Genomic in situ hybridization (GISH and fluorescence in situ hybridization (FISH confirmed the 1D/1A chromosome substitution. The presence or absence of einkorn high-molecular-weight (HMW glutenin subunits and the wheat Glu-D1d locus encoding the 5 + 10 subunits was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE, capillary zone electrophoresis, and allele-specific molecular markers. Significant differences were found among physicochemical properties (with the exception of the Hagberg falling number of all introgressive Triticale/T. monococcum lines and the secondary triticale lines. The wheat 1D/1A chromosome substitution also affected these properties. The results showed that in all introgressive triticale lines, the protein and gluten content, Zeleny sedimentation value, and water absorption capacity, were increased. The rheological parameters estimated using micro-farinograph, reomixer, and Kieffer dough extensibility systems also showed an appreciable increase in dough-mixing properties, maximum resistance to extension (Rmax, and dough extensibility. Introgressive Triticale/T. monococcum lines with 5 + 10 subunits have particularly favorable rheological parameters. The results obtained in this study suggest that the cultivated einkorn genome Am, in the context of hexaploid secondary triticale lines and with a wheat 1D/1A substitution, has the potential to improve gluten polymer interactions and be a valuable genetic resource for triticale quality improvement.

  20. Genetic Effect on Yield and Fiber Quality Traits of 16 Chromosome Substitution Lines in Upland Cotton

    Institute of Scientific and Technical Information of China (English)

    LUAN Ming-bao; GUO Xiang-mo; ZHANG Yongshan; YAO Jin-bo

    2008-01-01

    Evaluation of the genetic effect on yield and fiber quality can provide useful information on cotton breeding. Sixteen CSB lines and TM-1 introduced from USDA/ARS were used as male and top-crossed with three elite cultivars and the 51 F1 hybrids, 16 CSB lines, TM-1, and 3 elite cultivars were planted at the Cotton Research Institute of CAAS, Anyang, Henan Province and Xiajin, shandong Province, China. The yield traits and fiber quality data were obtained and additive and dominance effect on each trait were measured by AD model. Boll weight takes the largest additive proration, whereas boll number takes the least additive proration. The largest and the least dominant proration for lint yield and boll weight were measured, respectively. Fiber length has the additive and dominance effect, and dominance effect was slightly more than additive effect. Larger additive and no dominance effect on uniformity, micronaire, and fiber strength were measured. Significantly, positive additive effect on boll weight of CSB06 and CSB12Sh was observed. CSBI4Sh and CSB01 have significantly positive additive effect on 4 and 3 traits of fiber quality, respectively. CSB01 has the greatest dominant effect on lint yield among CSB lines. The dominant effect on fiber length of CSB lines showed positive. It is beneficial to use CSB06 and CSB12Sh as parents to improve boll size, to use CSB14Sh and CSB01 as parents to improve fiber quality. As for hybrid cotton breeding, it is reasonable using CSB01 to improve lint yield traits, and using CSB01, CSB11Sh, and CSB06 to improve fiber length.

  1. QTL Location and Epistatic Effect Analysis of 100-Seed Weight Using Wild Soybean (Glycine soja Sieb. & Zucc.) Chromosome Segment Substitution Lines.

    Science.gov (United States)

    Xin, Dawei; Qi, Zhaoming; Jiang, Hongwei; Hu, Zhenbang; Zhu, Rongsheng; Hu, Jiahui; Han, Heyu; Hu, Guohua; Liu, Chunyan; Chen, Qingshan

    2016-01-01

    Increasing the yield of soybean (Glycine max L. Merrill) is a main aim of soybean breeding. The 100-seed weight is a critical factor for soybean yield. To facilitate genetic analysis of quantitative traits and to improve the accuracy of marker-assisted breeding in soybean, a valuable mapping population consisting of 194 chromosome segment substitution lines (CSSLs) was developed. In these lines, different chromosomal segments of the Chinese cultivar Suinong 14 were substituted into the genetic background of wild soybean (Glycine soja Sieb. & Zucc.) ZYD00006. Based on these CSSLs, a genetic map covering the full genome was generated using 121 simple sequence repeat (SSR) markers. In the quantitative trait loci (QTL) analysis, twelve main effect QTLs (qSW-B1-1/2/3, qSW-D1b-1/2, qSW-D2-1/2, qSW-G-1/2/3, qSW-M-2 and qSW-N-2) underlying 100-seed weight were identified in 2011 and 2012. The epistatic effects of pairwise interactions between markers were analyzed in 2011 and 2012. The results clearly demonstrated that these CSSLs could be used to identify QTLs, and that an epistatic analysis was able to detect several sites with important epistatic effects on 100-seed weight. Thus, we identified loci that will be valuable for improving soybean 100-seed weight. These results provide a valuable foundation for identifying the precise location of genes of interest, and for designing cloning and marker-assisted selection breeding strategies targeting the 100-seed weight of soybean.

  2. Production of aneuhaploid and euhaploid sporocytes by meiotic restitution in fertile hybrids between durum wheat Langdon chromosome substitution lines and Aegilops tauschii

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Fertile F1 hybrids were obtained between durum wheat (Triticum durum Desf.) Langdon (LDN) and its 10 disomic substitution (LDN DS) lines with Aegilops tauschii accession AS60 without embryo rescue. Selfed seedset rates for hybrids of LDN with AS60 were 36.87% and 49,45% in 2005 and 2006, respectively. Similar or higher selfed seedset rates were observed in the hybrids of ID (1A), 1D (1B), 3D (3A), 4D (4B), 7D (TA), and 2D (2B) with AS60, while lower in hybrids of 3D (3B) + 3BL, 5D (5A) + 5AL, 5D (5B) + 5B and 6D (6B) + 6BS with AS60 compared with the hybrids of LDN with AS60. Observation of male gametogenesis showed that meiotic restitution, both first-division restitution (FDR) and single-division meiosis (SDM) resulted in the formation of functional unreduced gametes, which in turn produced seeds. Both euhaploid and aneuhaploid gametes were produced in Fi hybrids. This suggested a strategy to simultaneously transfer and locate major genes from the ancestral species T. turgidum or Ae. tauschii. Moreover, there was no significant difference in the aneuhaploid rates between the F1 hybrids of LDN and LDN DS lines with AS60, suggesting that meiotic pairing between the two D chromosomes in the hybrids of LDN DS lines with AS60 did not promote the formation of aneuhaploid gametes.

  3. Development and characterization of recombinant chromosome substitution lines (RCSLs) using Hordeum vulgare subsp. spontaneum as a source of donor alleles in a Hordeum vulgare subsp. vulgare background.

    Science.gov (United States)

    Matus, I; Corey, A; Filichkin, T; Hayes, P M; Vales, M I; Kling, J; Riera-Lizarazu, O; Sato, K; Powell, W; Waugh, R

    2003-12-01

    The ancestor of barley (Hordeum vulgare subsp. spontaneum) may be a source of novel alleles for crop improvement. We developed a set of recombinant chromosome substitution lines (RCSLs) using an accession of H. vulgare subsp. spontaneum (Caesarea 26-24, from Israel) as the donor and Hordeum vulgare subsp. vulgare 'Harrington' (the North American malting quality standard) as the recurrent parent via two backcrosses to the recurrent parent, followed by six generations of selfing. Here we report (i) the genomic architecture of the RCSLs, as inferred by simple sequence repeat (SSR) markers, and (ii) the effects of H. vulgare subsp. spontaneum genome segment introgressions in terms of three classes of phenotypes: inflorescence yield components, malting quality traits, and domestication traits. Significant differences among the RCSLs were detected for all phenotypes measured. The phenotypic effects of the introgressions were assessed using association analysis, and these were referenced to quantitative trait loci (QTL) reported in the literature. Hordeum vulgare subsp. spontaneum, despite its overall inferior phenotype, contributed some favorable alleles for agronomic and malting quality traits. In most cases, the introgression of the ancestral genome resulted in a loss of desirable phenotypes in the cultivated parent. Although disappointing from a plant breeding perspective, this finding may prove to be a useful tool for gene discovery.

  4. Whole-Genome Resequencing of a Cucumber Chromosome Segment Substitution Line and Its Recurrent Parent to Identify Candidate Genes Governing Powdery Mildew Resistance

    Science.gov (United States)

    Yu, Ting; Xu, Xuewen; Yan, Yali; Qi, Xiaohua; Chen, Xuehao

    2016-01-01

    Cucumber is an economically important vegetable crop worldwide. Powdery mildew (PM) is one of the most severe diseases that can affect cucumber crops. There have been several research efforts to isolate PM resistance genes for breeding PM-resistant cucumber. In the present study, we used a chromosome segment substitution line, SSL508-28, which carried PM resistance genes from the donor parent, JIN5-508, through twelve generations of backcrossing with a PM-susceptible inbred line, D8. We performed whole-genome resequencing of SSL508-28 and D8 to identify single nucleotide polymorphisms (SNPs), and insertions and deletions (indels). When compared against the reference genome of the inbred cucumber line 9930, a total of 468,616 SNPs and 67,259 indels were identified in SSL508-28, and 537,352 SNPs and 91,698 indels were identified in D8. Of these, 3,014 non-synonymous SNPs and 226 frameshift indels in SSL508-28, and 3,104 non-synonymous SNPs and 251 frameshift indels in D8, were identified. Bioinformatics analysis of these variations revealed a total of 15,682 SNPs and 6,262 indels between SSL508-28 and D8, among which 120 non-synonymous SNPs and 30 frameshift indels in 94 genes were detected between SSL508-28 and D8. Finally, out of these 94 genes, five resistance genes with nucleotide-binding sites and leucine-rich repeat domains were selected for qRT-PCR analysis. This revealed an upregulation of two transcripts, Csa2M435460.1 and Csa5M579560.1, in SSL508-28. Furthermore, the results of qRT-PCR analysis of these two genes in ten PM resistant and ten PM susceptible cucumber lines showed that when exposed to PM, Csa2M435460.1 and Csa5M579560.1 exhibited a higher expression level of resistant lines than susceptible lines. This indicates that Csa2M435460.1 and Csa5M579560.1 are candidate genes for PM resistance in cucumber. In addition, the non-synonymous SNPs in Csa2M435460.1 and Csa5M579560.1, identified in SSL508-28 and D8, might be the key to high PM-resistance in

  5. [Effect of rye Secale cereale L. chromosomes 1R and 3R on polyembryony expression in hybrid combinations between (Hordeum vulgare L.)-Triticum aestivum L. alloplasmic recombinant lines and wheat T. aestivum L.-rye S. cereale L. substitution lines].

    Science.gov (United States)

    Pershina, L A; Rakovtseva, T S; Belova, L I; Deviatkina, E P; Silkova, O G; Kravtsova, L A; Shchapova, A I

    2007-07-01

    The effect of rye chromosomes on polyembryony was studied for reciprocal hybrid combinations between (Hordeum vulgare L.)-Triticum aestivum L. alloplasmic recombinant lines and five wheat T. aestivum L. (cultivar Saratovskaya 29)-rye Secale cereale L. (cultivar Onokhoiskaya) substitution lines: IR(1D), 2R(2D), 3R(3B), 5R(5A), and 6R(6A), and for direct hybrid combinations between the [H. marinum ssp. gussoneanum (H. geniculatum All.)]-T. aestivum alloplasmic recombinant line and the wheat-rye substitution lines 1R (1A), 1R (1D), and 3R(3B). Chromosomes 1R and 3R of rye cultivar Onokhoiskaya proved to affect the expression of polyembryony in the hybrid combinations that involved the alloplasmic recombinant lines of common wheat as maternal genotypes. Based on this finding, polyembryony was regarded as a phenotypic expression of nuclear-cytoplasmic interactions where an important role is played by rye chromosomes 1R and 3R and the H. vulgare cytoplasm. Consideration is given to the association between the effect of rye chromosomes 1R and 3R on polyembryony in the [(Hordeum)-T. aestivum x wheat-rye substitution lines] hybrid combinations and their stimulating effect on the development on angrogenic embryoids in isolated anther cultures of the wheat-rye substitution lines.

  6. [Chromosome composition of wheat-rye lines and the influence of rye chromosomes on disease resistance and agronomic traits].

    Science.gov (United States)

    Chumanova, E V; Efremova, T T; Trubacheeva, N V; Arbuzova, V S; Rosseeva, L P

    2014-11-01

    Identification of the chromosomal composition of common wheat lines with rye chromosomes was carried out using genomic in situ hybridization and 1RS- and 5P-specific PCR markers. It was demonstrated that wheat chromosomes 5A or 5D were substituted by rye chromosome 5R in the wheat-rye lines. It was established that one of the lines with complex disease resistance contained rye chromosome 5R and T1RS.1BL, while another line was found to contain, in addition to T1RS.1BL, a new Robertsonian translocation, T5AS.5RL. Substitution of the wheat chromosome 5A with the dominant Vrn-A1 gene for the Onokhoiskaya rye chromosome 5R led to lengthening of the germination-heading period or to a change in the type of development. A negative influence of T1RS.1BL on SDS sedimentation volume and grain hardness was demonstrated, along with a positive effect of the combination of T1RS. BL and 5R(5D) substitution on grain protein content. Quantitative traits of the 5R(5A) and 5R(5D) substitution lines were at the level of recipient cultivars. A line with two translocations, T1RS.1BL + T5AS.5R1, appeared to be more productive as compared to the line carrying T1RS.1BL in combination with the 5R(5D) substitution.

  7. Monosomic and double monosomic substitutions of Hordeum bulbosum L. chromosomes into H. vulgare L.

    Science.gov (United States)

    Pickering, R A

    1992-07-01

    One of the aims of the interspecific crossing programme between Hordeum vulgare L. and H. bulbosum L. has been to introgress desirable genes into barley from the wild species. However, despite their close taxonomic relationship there have been few reports of achieving this objective using amphidiploid hybrids. In order to broaden the range of available hybrids, partially fertile triploids between H. vulgare (2n = 2x = 14) and H. bulbosum (2n = 4x = 28) were developed and crossed with H. vulgare as female parent. From 580 progeny which were screened, eight putative single monosomic chromosome substitution lines and one double monosomic substitution were identified by cytological analysis. These involved the substitution of H. vulgare chromosome 1 (two lines), 6 (four lines), 6L (one line), 7 (one line) and 1 + 4 (one line) by their respective H. bulbosum homoeologues. The H. bulbosum chromosome was frequently eliminated during plant development, but it was observed regularly in pollen mother cells of two lines. However, pairing between the H. bulbosum chromosome and its H. vulgare homoeologue was low. Several of the lines were more resistant than their H. vulgare parents to powdery mildew (Erysiphe graminis DC. f.sp. hordei Em. Marchai), net blotch (Drechslera teres Sacc.) and scald (Rhynchosporium secalis (Oudem.) Davis). Apart from their use in studying genome relationships, their value to plant breeders will depend on the ease of inducing translocations between the parental chromosomes.

  8. Chromosome substitutions in progeny of hybrids Triticum aestivum x Triticum timopheevii resistant to brown rust and powdery mildew

    Energy Technology Data Exchange (ETDEWEB)

    Badaeva, E.D. [Engelhardt Institute of Molecular Biology, Moscow (Russian Federation); Badaev, N.S. [Bioengineering Center, Moscow (Russian Federation); Enno, T.M.; Peusha, H.O. [Institute of Experimental Biology, Moscow (Russian Federation); Zeller, F.J. [Institut fuer Pflanzenbau und Pflanzenzuechtung, Muenchen (Germany)

    1995-01-01

    By the C-banding technique, chromosome analysis of introgressive wheat lines derived from the tetraploid species T. timopheevii and T. militinae, with complex immunity to pathogens, was performed. It is shown that all hybrid lines possess genetic material of T. timopheevii and are stable in chromosome number (2n = 6x = 42) and composition. In the lines studied, the number of substitutions per genome varied from one to three; variation in the spectrum of chromosome substitutions was observed. Karyotypes of lines 146-155-T, SMT 30, SMT 34, SMT 37, and SMT 45, resistant to brown rust and powdery mildew, had one common chromosome substitution 6B(6G). It is suggested that the resistance to pathogens of these lines is determined by chromosome 6G of T. timopheevii.

  9. Dissecting the genetic basis for the effect of rice chalkiness, amylose content, protein content, and rapid viscosity analyzer profile characteristics on the eating quality of cooked rice using the chromosome segment substitution line population across eight environments.

    Science.gov (United States)

    Liu, Xiaolu; Wan, Xiangyuan; Ma, Xiaodong; Wan, Jianmin

    2011-01-01

    Quantitative trait locus (QTL) mapping and stability analysis were carried out for 16 rice (Oryza sativa L.) quality traits across eight environments, by using a set of chromosome segment substitution lines with 'Asominori' as genetic background. The 16 quality traits include percentage of grain with chalkiness (PGWC), area of chalky endosperm (ACE), amylose content (AC), protein content (PC), peak viscosity, hot paste viscosity, cool paste viscosity, breakdown viscosity (BDV), setback viscosity (SBV), consistency viscosity, cooked-rice luster (LT), scent, tenderness (TD), viscosity, elasticity, and the integrated values of organleptic evaluation (IVOE). A total of 132 additive effect QTLs are detected for the 16 quality straits in the eight environments. Among these QTLs, 56 loci were detected repeatedly in at least three environments. Interestingly, several QTL clusters were observed for multiple quality traits. Especially, one QTL cluster near the G1149 marker on chromosome 8 includes nine QTLs: qPGWC-8, qACE-8, qAC-8, qPC-8a, qBDV-8a, qSBV-8b, qLT-8a, qTD-8a, and qIVOE-8a, which control PGWC, ACE, AC, PC, BDV, SBV, LT, TD, and IVOE, respectively. Moreover, this QTL cluster shows high stability and repeatability in all eight environments. In addition, one QTL cluster was located near the C2340 marker on chromosome 1 and another was detected near the XNpb67 marker on chromosome 2; each cluster contained five loci. Near the C563 marker on chromosome 3, one QTL cluster with four loci was found. Also, there were nine QTL clusters that each had two or three loci; however, their repeatability in different environments was relatively lower, and the genetic contribution rate was relatively smaller. Considering the correlations among all of the 16 quality traits with QTL cluster distributions, we can conclude that the stable and major QTL cluster on chromosome 8 is the main genetic basis for the effect of rice chalkiness, AC, PC, and rapid viscosity analyzer profile

  10. Constructing Molecular Marker Linkage Maps of Chromosome 14Sh and 22Sh and QTL Mapping for Major Traits by Use of Substitution Lines of Gossypium hirsutum L.

    Institute of Scientific and Technical Information of China (English)

    GUO Xiang-mo; LUAN Ming-bao; SAHA Sukumar; JENKINS Johnie N

    2008-01-01

    @@ CSB14Sh,which is isogenic for its recurrent parent TM-1 except for chromosome 14 short arm,was crossed with TM-1,and the F2 population was produced.A total of 3800 SSR primer pairs covering the whole genome were used to screen polymorphism among two parents,TM-1 and CSB14Sh,and their F1 progeny,which resulted in 15 polymorphic primer pairs.The 15 polymorphic primer pairs amplified 23 marker loci.

  11. Development of inter-specific chromosomes segment substitution libraries (CSSL) in rice

    Science.gov (United States)

    Six libraries of inter-specific Chromosome Segment Substitution Lines (CSSLs) of rice are being developed as pre-breeding materials and genetic stocks. Three accessions of O. rufipogon were selected as donors, based on phylogenetic, geographical and morphological divergence, and crossed with two rec...

  12. Chromosome substitution strain assessment of a Huntington's disease modifier locus.

    Science.gov (United States)

    Ramos, Eliana Marisa; Kovalenko, Marina; Guide, Jolene R; St Claire, Jason; Gillis, Tammy; Mysore, Jayalakshmi S; Sequeiros, Jorge; Wheeler, Vanessa C; Alonso, Isabel; MacDonald, Marcy E

    2015-04-01

    Huntington's disease (HD) is a dominant neurodegenerative disorder that is due to expansion of an unstable HTT CAG repeat for which genome-wide genetic scans are now revealing chromosome regions that contain disease-modifying genes. We have explored a novel human-mouse cross-species functional prioritisation approach, by evaluating the HD modifier 6q23-24 linkage interval. This unbiased strategy employs C57BL/6J (B6J) Hdh(Q111) knock-in mice, replicates of the HD mutation, and the C57BL/6J-chr10(A/J)/NaJ chromosome substitution strain (CSS10), in which only chromosome 10 (chr10), in synteny with the human 6q23-24 region, is derived from the A/J (AJ) strain. Crosses were performed to assess the possibility of dominantly acting chr10 AJ-B6J variants of strong effect that may modulate CAG-dependent Hdh(Q111/+) phenotypes. Testing of F1 progeny confirmed that a single AJ chromosome had a significant effect on the rate of body weight gain and in Hdh(Q111) mice the AJ chromosome was associated subtle alterations in somatic CAG instability in the liver and the formation of intra-nuclear inclusions, as well as DARPP-32 levels, in the striatum. These findings in relatively small cohorts are suggestive of dominant chr10 AJ-B6 variants that may modify effects of the CAG expansion, and encourage a larger study with CSS10 and sub-strains. This cross-species approach may therefore be suited to functional in vivo prioritisation of genomic regions harbouring genes that can modify the early effects of the HD mutation.

  13. Development of T. aestivum L.-H. californicum alien chromosome lines and assignment of homoeologous groups of Hordeum californicum chromosomes.

    Science.gov (United States)

    Fang, Yuhui; Yuan, Jingya; Wang, Zhangjun; Wang, Haiyan; Xiao, Jin; Yang, Zhixi; Zhang, Ruiqi; Qi, Zengjun; Xu, Weigang; Hu, Lin; Wang, Xiu-E

    2014-08-20

    Hordeum californicum (2n = 2x = 14, HH) is resistant to several wheat diseases and tolerant to lower nitrogen. In this study, a molecular karyotype of H. californicum chromosomes in the Triticum aestivum L. cv. Chinese Spring (CS)-H. californicum amphidiploid (2n = 6x = 56, AABBDDHH) was established. By genomic in situ hybridization (GISH) and multicolor fluorescent in situ hybridization (FISH) using repetitive DNA clones (pTa71, pTa794 and pSc119.2) as probes, the H. californicum chromosomes could be differentiated from each other and from the wheat chromosomes unequivocally. Based on molecular karyotype and marker analyses, 12 wheat-alien chromosome lines, including four disomic addition lines (DAH1, DAH3, DAH5 and DAH6), five telosomic addition lines (MtH7L, MtH1S, MtH1L, DtH6S and DtH6L), one multiple addition line involving H. californicum chromosome H2, one disomic substitution line (DSH4) and one translocation line (TH7S/1BL), were identified from the progenies derived from the crosses of CS-H. californicum amphidiploid with common wheat varieties. A total of 482 EST (expressed sequence tag) or SSR (simple sequence repeat) markers specific for individual H. californicum chromosomes were identified, and 47, 50, 45, 49, 21, 51 and 40 markers were assigned to chromosomes H1, H2, H3, H4, H5, H6 and H7, respectively. According to the chromosome allocation of these markers, chromosomes H2, H3, H4, H5, and H7 of H. californicum have relationship with wheat homoeologous groups 5, 2, 6, 3, and 1, and hence could be designated as 5H(c), 2H(c), 6H(c), 3H(c) and 1H(c), respectively. The chromosomes H1 and H6 were designated as 7H(c) and 4H(c), respectively, by referring to SSR markers located on rye chromosomes.

  14. Microdissection and chromosome painting of the alien chromosome in an addition line of wheat-Thinopyrum intermedium

    Science.gov (United States)

    The chromosome painting is an efficient tool for chromosome research. However, plant chromosome painting is relatively underdeveloped. In this study, chromosome painting was developed and used to identify alien chromosomes in TAi-27, a wheat-Thinopyrum intermedium addition line, and chromosomes of...

  15. 基于玉米87-1综3单片段代换系的穗长QTL分析%QTL Mapping for Ear Length Based on Chromosome Single Segment Substitution Lines of 87-1 Zong3 in Maize

    Institute of Scientific and Technical Information of China (English)

    王帮太; 张书红; 席章营

    2012-01-01

    以优良玉米自交系综3为供体、87-1为受体,利用回交和SSR标记辅助选择相结合的方法,获得了51份纯合的染色体单片段代换系(Single Segment Substitution Line,SSSL),每个SSSL内只含有一个来源于供体的染色体片段.51个代换片段不均匀分布在玉米10条染色体上,代换片段长度在1.75~172.45 cM之间,平均长度为24.44cM.覆盖玉米基因组的总长度为933.90 cM,覆盖率为40.20%.2008年在郑州利用17份SSSL材料及在三亚利用39份SSSL材料对玉米穗长进行了1年2点的表型鉴定,共检测到20个穗长QTL,加性效率百分率在-12.10%~19.18%之间.结果表明,这些单片段代换系存在较大的遗传变异,是用于玉米复杂性状的QTL鉴定、基因克隆及功能分析的理想材料.%A wide population consisting of 51 chromosome single-segment substitution lines(SSSLs) were developed from an advanced backcross procedure with the marker-assisted selection of simple sequence repeat (SSR) markers using the elite maize inbred line 87-1 as the recipient and Zong3 as the donor. Each SSSL contains a single substituted chromosome segment derived from donor Zong3 in the genetic background of 87-1. The total size of the substituted segments in the SSSL population was 1 246.55 cM, and the genome covered length was 933.90 cM, with a covered ratio of 40.2%. The length of these substituted segments ranged from 1.75 - 172.45 cM, with an average of 24.44 cM. To evaluate the potential application of these SSSLs for QTL detection, phenotypic variations of ear length of 39 SSSLs were observed in two different places. Twenty-three QTLs for ear length were identified and mapped on substituted segment, which the percentages of additive effects varied from -12.10% to 19.18%. The results demonstrated that SSSLs are excellent genetic materials for QTL identification of dissect complex traits, gene cloning and functional genomics.

  16. Chromosome abnormalities in Japanese Burkitt lymphoma cell lines.

    Directory of Open Access Journals (Sweden)

    Hamasaki,Kazuhide

    1982-02-01

    Full Text Available Six established Japanese Burkitt lymphoma (BL cell lines including one case with null cell type were studied by chromosomal banding techniques. The modal chromosome number was diploid or nearly diploid in five cases and hyperdiploid in one case. The marker chromosome 14q+ was observed in four of the six cases; the origin of the extra band was a chromosome 8 in three including the null cell case but could not be identified in the other. The two cases lacking the 14q+ marker had variant translocations involving the long arm of chromosome 8, one of which carried a translocation, t(8;22 (q24;q13 and the other a translocation, t(2;8 (p12;q24. Although structural and/or numerical aberrations were found in all six cell lines, chromosome 8 was the one most consistently involved. This frequent involvement of chromosome 8 in aberrations; therefore, may be an important event in the development of BL rather than the presence of a 14q+ marker chromosome.

  17. 低磷对小麦代换系幼苗根系保护酶活性和丙二醛含量的影响及染色体效应%Effects of Phosphorus Deficiency Stress on Protective Enzyme Activities,MDA Content and Chromosome of Wheat Substitution Lines Seedling Roots

    Institute of Scientific and Technical Information of China (English)

    米少艳; 靖姣姣; 白志英; 李存东

    2013-01-01

      以中国春-Synthetic 6x染色体代换系及其亲本为材料,通过测定不同磷处理条件下根系抗氧化酶SOD、POD活性和丙二醛(MDA)含量,研究低磷胁迫对小麦代换系酶活性的影响,并对耐低磷胁迫特性的基因进行染色体定位。结果表明,低磷胁迫下,小麦代换系苗期根系SOD和POD活性显著升高,丙二醛含量降低。 Synthetic 6x的3A、4A、5A和7A染色体上可能存在诱导根系SOD活性增强的基因,5A、1D和2D染色体上可能存在诱导根系POD活性增强的基因,1A、2A、4B、6B和7D染色体上可能存在抑制根系MDA含量增高的基因。%The effects of phosphorus deficiency stress on enzyme activity in wheat was studied by determining antioxidant enzymes SOD,POD activities and MDA content and locating the gene controlling antioxidant enzymes SOD,POD activities and MDA content at the roots of the seedling stage using wheat substitution lines between Chi -nese Spring(CS)and Synthetic 6x.The results showed that SOD and POD activities increased ,MDA content reduced under phosphorus deficiency stress .This explains that the increased of antioxidant enzyme activity might reduce MDA content and lower membrane lipid peroxidation level ,to improve their resistance.The genes promoting SOD activity might be located on 3A,4A,5A and 7A chromosome of Synthetic 6x;and the genes promoting POD activity might be located on 5A,1D and 2D chromosome,while the genes inhibiting content might be located on 5A,2D,5D and 7D chromosome of Synthetic 6x.

  18. Mapping QTL for Traits Associated with Resistance to Ferrous Iron Toxicity in Rice (Oryza sativa L.),Using japonica Chromosome Segment Substitution Lines%利用粳稻染色体片段置换系群体检测水稻抗亚铁毒胁迫有关性状QTL

    Institute of Scientific and Technical Information of China (English)

    万建林; 翟虎渠; 万建民; 安井秀; 吉村淳

    2003-01-01

    A mapping population of 66 japonica chromosome segment substitution lines (CSSLs) in indica genetic background,derived from a cross between a japonica variety Asominori and an indica variety IR24 by the single-seed descent,backcrossing and marker-assisted selection,was used to detect quantitative trait loci (QTLs) for leaf bronzing index (LBI),stem dry weight (SDW),plant height (PH),root length (RL) and root dry weight (RDW) under Fe2+ stress condition in rice.Two parents and 66 japonica CSSLs were phenotyped for the traits by growing them in Fe2+ toxicity nutrient solution.A total of fourteen QTLs were detected on chromosome 3,6,7,9,11 and 12,respectively,with LOD of QTLs ranging from 2.72 to 6.63.Three QTLs controlling LBI were located at the region of C515~XNpb279,R2638~C1263 and G1465~C950 on chromosome 3,9 and 11,their contributions to whole variation were 16.45%,11.16% and 28.02%,respectively.Comparing with the other mapping results,the QTL for LBI located at the region of C515~XNpb279 on chromosome 3 was identical with the QTL for chlorophyll content on a rice function map.The results indicated that ferrous iron toxicity of rice is characterized by bronzing spots on the lower leaves,which spread over the whole leaves,causing the lower leaves to turn dark gray and to product chlorophyll catabolites or derivatives which reduce cytotoxicity of some heavy metals,such as ferrous iron.Futhermore,the QTL for LBI,SDW and RDW located at the region of G1465~C950 on chromosome 11 is a major QTL.Whether the QTL for SDW ,PH,RL and RDW at the region of XNpb386~XNpb342 on chromosome 6 is associated with resistance to ferrous iron toxicity need further studies.Our goal is to identify breeding materials for resistance to Fe2+ toxicity through marker-assisted selection based on the detected markers.%潜育性水稻田广泛分布于中国、斯里兰卡、印度、印度尼西亚、塞拉里昂、利比亚、尼日利亚、哥伦比亚和菲律宾等国,其

  19. 小麦-黑麦染色体代换易位系创新材料的选育及抗病性研究%Development and Disease Resistance Survey of New Wheat-rye Chromosomal Substitution-translocation Lines

    Institute of Scientific and Technical Information of China (English)

    舒焕麟; 杨家秀; 杨足君; 李光蓉

    2000-01-01

    Under the condition of wheat stripe rust epidemic induced by spreader lines. 5 wheat-rye substitutiontranslocation lines including NR98117- 9S are developed from the accession of “Currency/Xiaoyan 6//Chuanyu 12/3/A302” through the treatment of wheat-alien direct hybridization backcrossing together with open-pollination These lines exhibited not only the better agronomical traits than their wheat parents Xiaoyan 6 and Chuanyu 12, but also high resistance to wheat stripe rust mixed races and race CYR - 31. Therefore, the above lines can be utilized as important parents to Sichuan wheat breeding for stripe rust resistance. In addition, the reliability of indirect selection in the process of wheat breeding for the development of wheat - rye chromosomal substitution-translocation lines is also discussed in the present paper.%利用小麦-异源直接杂交法回交结合开放授粉处理,在诱发材料制造的条锈病流行条件下,从组合Curren-cy/小偃6号//川育12号/3/A302中选育出小麦-黑麦染色体代换易位系NR98117-9S等5个小麦材料。这些材料大都具有与亲本小麦品种小偃6号及川育12号不相上下的农艺性状,对条锈生理小种条中31和混合菌种表现高抗,可作为四川小麦抗条锈病育种的亲本加以利用。文中还讨论了小麦育种中的间接选择在创制小麦黑麦染色体代换易位系上的可行性。

  20. Identification of QTLs for Plant Height and Its Components by Using Single Segment Substitution Lines in Rice (Oryza sativa)

    Institute of Scientific and Technical Information of China (English)

    HE Feng-hua; XI Zhang-ying; ZENG Rui-zhen; Akshay TALUKDAR; ZHANG Gui-quan

    2005-01-01

    QTLs for plant height and its components on the substituted segments of fifty-two single segment substitution lines (SSSLs)in rice were identified through t-test (P≤0.001) for comparison between each SSSL and recipient parent Huajingxian 74. On the 14 substituted segments, 24 QTLs were detected, 10 for plant height, 2 for panicle length, 4 for length of thefirst internode from the top,5 for length of the second internode from the top and 3 for length of the third internode from the top, respectively. All these QTLs were distributed on nine rice chromosomes except chromosomes 5, 9 and 11. The additive effect ranged from -4.08 to 3.98 cm, and the additive effect percentages varied from -19.35% to 10.43%.

  1. Propranolol induced chromosomal aberrations in Chinese hamster ovary cell line

    Directory of Open Access Journals (Sweden)

    Mozhgan Sedigh-Ardekani

    2013-03-01

    Full Text Available Propranolol (PL, a non-selective beta-blocker, is a cardiovascular drug widely used to treat hypertension. The present study was concerned with assessing the cytogenetic effects of this drug on Chinese hamster ovary (CHO cell line. MTT assay was then carried out to determine the cytotoxicity index (IC50 of the drug. The IC50 value of PL was 0.43±0.02 mM. To investigate the clastogenic effects of the drug, chromatid and chromosome breaks and polyploidy in metaphases were analyzed. CHO cells were exposed to different concentrations of the drug (0.1, 0.2, 0.3, 0.4 mM for 24 hours. Considering that PL has liver metabolism, experiments were carried out in the presence and absence of the metabolic activation system (S9 mix. Mitomycin-C and sodium arsenite were used as positive controls. It was observed that in cells treated with different PL concentrations as 0.1, 0.2 and 0.3 mM, the frequency of chromatid and chromosome breaks as well as polyploidy increased when compared with untreated CHO cells. The addition of S9 mix significantly decreased the chromatid breaks, chromosome breaks and polyploidy compared to the treatment of PL alone. It is concluded that, PL causes chromatid and chromosome aberrations in CHO cell line and the metabolic activation system (S9 mix, playing an important role in drug cytotoxicity reduction.

  2. Chromosome Substitution Lines:Useful Genomic Resources in Cotton

    Institute of Scientific and Technical Information of China (English)

    SAHA Sukumar; JENKINS Johnie N; MCARTY Jack C; WU Ji-xiang; STELLY David

    2008-01-01

    @@ The genus Gossypium is a very diverse one with about 50 species.However,a very narrow germplasm base is presently being used for genetic improvement of Upland cotton.The wild tetraploid cotton species are reservoirs of important genes for pest and disease resistance,and for improved agronomic and fiber traits.Two of the most important forces impeding Upland cotton improvement are" 1)the paucity of information about genes that control important traits,and 2) the need for extensive usage of diverse germplasm.

  3. Novel Bread Wheat Lines Enriched in Carotenoids Carrying Hordeum chilense Chromosome Arms in the ph1b Background

    Science.gov (United States)

    Rey, María-Dolores; Calderón, María-Carmen; Rodrigo, María Jesús; Zacarías, Lorenzo; Alós, Enriqueta; Prieto, Pilar

    2015-01-01

    The use of crop wild relative species to improve major crops performance is well established. Hordeum chilense has a high potential as a genetic donor to increase the carotenoid content of wheat. Crosses between the 7Hch H. chilense substitution lines in wheat and the wheat pairing homoeologous1b (ph1b) mutant allowed the development of wheat-H. chilense translocation lines for both 7Hchα and 7Hchβ chromosome arms in the wheat background. These translocation lines were characterized by in situ hybridization and using molecular markers. In addition, reverse phase chromatography (HPLC) analysis was carried out to evaluate the carotenoid content and both 7Hchα∙7AL and 7AS∙7Hchβ disomic translocation lines. The carotenoid content in 7Hchα∙7AL and 7AS∙7Hchβ disomic translocation lines was higher than the wheat-7Hch addition line and double amount of carotenoids than the wheat itself. A proteomic analysis confirmed that the presence of chromosome 7Hch introgressions in wheat scarcely altered the proteomic profile of the wheat flour. The Psy1 (Phytoene Synthase1) gene, which is the first committed step in the carotenoid biosynthetic pathway, was also cytogenetically mapped on the 7Hchα chromosome arm. These new wheat-H. chilense translocation lines can be used as a powerful tool in wheat breeding programs to enrich the diet in bioactive compounds. PMID:26241856

  4. Novel Bread Wheat Lines Enriched in Carotenoids Carrying Hordeum chilense Chromosome Arms in the ph1b Background.

    Directory of Open Access Journals (Sweden)

    María-Dolores Rey

    Full Text Available The use of crop wild relative species to improve major crops performance is well established. Hordeum chilense has a high potential as a genetic donor to increase the carotenoid content of wheat. Crosses between the 7Hch H. chilense substitution lines in wheat and the wheat pairing homoeologous1b (ph1b mutant allowed the development of wheat-H. chilense translocation lines for both 7Hchα and 7Hchβ chromosome arms in the wheat background. These translocation lines were characterized by in situ hybridization and using molecular markers. In addition, reverse phase chromatography (HPLC analysis was carried out to evaluate the carotenoid content and both 7Hchα∙7AL and 7AS∙7Hchβ disomic translocation lines. The carotenoid content in 7Hchα∙7AL and 7AS∙7Hchβ disomic translocation lines was higher than the wheat-7Hch addition line and double amount of carotenoids than the wheat itself. A proteomic analysis confirmed that the presence of chromosome 7Hch introgressions in wheat scarcely altered the proteomic profile of the wheat flour. The Psy1 (Phytoene Synthase1 gene, which is the first committed step in the carotenoid biosynthetic pathway, was also cytogenetically mapped on the 7Hchα chromosome arm. These new wheat-H. chilense translocation lines can be used as a powerful tool in wheat breeding programs to enrich the diet in bioactive compounds.

  5. Molecular cytogenetic characterization of a new wheat Secale africanum 2Ra(2D) substitution line for resistance to stripe rust

    Indian Academy of Sciences (India)

    Mengping Lei; Guangrong Li; Sufen Zhang; Cheng Liu; Zujun Yang

    2011-08-01

    A stable, highly fertile wheat Secale africanum substitution line LF24, derived from the F7 generation of a cross between Mianyang11 (MY11) and Triticum durum, S. africanum amphiploid (YF) was identified through molecular cytogenetic analysis. Application of C-banding, in situ hybridization and molecular markers analysis showed that LF24 was a wheat S. africanum 2Ra(2D) substitution line. When inoculated with stripe rust isolates, T. durum and MY11 were highly susceptible, while S. africanum, YF and LF24 were immune. It is confirmed through molecular cytogenetic analysis that the stripe rust resistance of LF24 was derived from S. africanum chromosome 2Ra. We compared the banding patterns and disease resistance of reported chromosomes 2R from different S. cereale introduced into wheat background, and found that there was new stripe rust resistance gene(s) on S. africanum 2Ra. LF24 is a new substitution line which can be used as stripe rust resistant source in wheat improvement.

  6. Development of Triticum aestivum-Leymus racemosus ditelosomic substitution line 7Lr#1S(7A) with resistance to wheat scab and its meiotic behavior analysis

    Institute of Scientific and Technical Information of China (English)

    WANG LinSheng; CHEN PeiDu

    2008-01-01

    Leymus racemosus is highly resistant to wheat scab (Fusarum head bright). The transfer of scab re-sistant gene from L. racemosus to Triticum aestivum is of great significance for broadening the base of wheat resistance. In the present study, the pollen of T. aestivum-L, racemosus monosomic addition linewith scab resistance was treated by irradiation with 1200 R 60Co-γ-rays prior to pollinating to emasculated wheat cv. Mianyang 85-45. Nine plants with a telocentric chromosome 7Lr#1S were observed in M1,and one ditelosomic substitution line 7Lr#1S was selected from selfcrossing progenies and confirmed by chromosome C-banding and GISH. Furthermore, a co-dominant EST-SSR marker CINAU 31 was em-ployed to identify this substitution line. A pair of chromosome 7A of common wheat were found to be replaced by a pair of telocentric chromosome 7Lr#1S, and further investigation showed that chromo-some configuration of the substitution line at MI of PMCs after GISH was 17.50(Ⅱ) w + 2.19 (Ⅱ)w +0.42 (Ⅱ)7Lr#1S + 1.08 Ⅰ7Lr#1S + 0.69 Ⅰw. Two telocentric chromosomes paired as a bivalent in 59.7% of PMCs.Abnormal chromosome behaviors of telocentric chromosomes were observed in part of PMCs at ana-phase Ⅰ and telophase Ⅰ, including the moving of two telocentric chromosomes to the same pole, lag-ging and earlier separation of their sister chromatid. All these abnormal behaviors can be grouped into three distinct types of tetrads according to different numbers of 7Lr#1S in their daughter cells and various micronucieus in some tetrads. However, due to the high transmission frequency of the female and male gametes with a 7Lr#1S, 84% of the selfcrossing progeny plants had ditelosomic substitution. The substitution line showed high resistance to wheat scab in a successive two-year test both in the greenhouse and field; hence, the line will be particularly valuable for alien gene mapping, small frag-ment translocation induction and telosomic cytological behavior analysis.

  7. A Chromosome Segment Substitution Library of Weedy Rice for Genetic Dissection of Complex Agronomic and Domestication Traits.

    Directory of Open Access Journals (Sweden)

    Prasanta K Subudhi

    Full Text Available Chromosome segment substitution lines (CSSLs are a powerful alternative for locating quantitative trait loci (QTL, analyzing gene interactions, and providing starting materials for map-based cloning projects. We report the development and characterization of a CSSL library of a U.S. weedy rice accession 'PSRR-1' with genome-wide coverage in an adapted rice cultivar 'Bengal' background. The majority of the CSSLs carried a single defined weedy rice segment with an average introgression segment of 2.8 % of the donor genome. QTL mapping results for several agronomic and domestication traits from the CSSL population were compared with those obtained from two recombinant inbred line (RIL populations involving the same weedy rice accession. There was congruence of major effect QTLs between both types of populations, but new and additional QTLs were detected in the CSSL population. Although, three major effect QTLs for plant height were detected on chromosomes 1, 4, and 8 in the CSSL population, the latter two escaped detection in both RIL populations. Since this was observed for many traits, epistasis may play a major role for the phenotypic variation observed in weedy rice. High levels of shattering and seed dormancy in weedy rice might result from an accumulation of many small effect QTLs. Several CSSLs with desirable agronomic traits (e.g. longer panicles, longer grains, and higher seed weight identified in this study could be useful for rice breeding. Since weedy rice is a reservoir of genes for many weedy and agronomic attributes, the CSSL library will serve as a valuable resource to discover latent genetic diversity for improving crop productivity and understanding the plant domestication process through cloning and characterization of the underlying genes.

  8. The Meiotic Behavior of an Alien Chromosome in Triticum aestivum-Haynaldia villosa Monosomic Addition Lines

    Institute of Scientific and Technical Information of China (English)

    LI Rui-fen; LIANG Hong-xia; ZHAO Mao-lin

    2002-01-01

    By the combination of cytological analysis and using genomic in situ hybridization technique to identify an alien chromosome in wheat-Haynaldia villosa monosomic addition lines, we studied the meiotic behavior of the alien chromosome. The results indicated that the frequency of bivalent pairing was lower than the value expected in PMCs of two monosomic addition lines, the frequency of wheat chromosomes unpairing increased, and the wheat homologous chromosome pairing was interfered with by the added chromosome 6V at metaphase I. The chromosome 6V lagged in 20.3% -29.3% of PMCs, sister chromatids 6V early divided in 29.0% - 34.1% of PMCs, the single chromosome 6V in 18.2% - 26.1% of PMCs went to a pole randomly,the breakage frequency of chromosome 6V was 1.2% - 2.9%. Meanwhile, it was also found that several wheat chromosomes showed earlier division, lagging and breakage in a few PMCs. It revealed that the added chromosome 6V influenced the behavior of wheat chromosomes at anaphase. It was also found that the translocation was produced between 6V and wheat chromosomes in 1.2% of PMCs. It offered evidence for translocation between wheat and Haynaldia villosa 6V chromosomes.

  9. Development of Triticum aestivum-Leymus racemosus translocation lines using gametocidal chromosomes

    Institute of Scientific and Technical Information of China (English)

    袁建华; 陈佩度; 刘大钧

    2003-01-01

    Specific chromosomes of certain Aegilops species introduced into wheat genome background may often facilitate chromosome breakage and refusion, and finally result in a variety of chromosome restructuring. Such a phenomenon is commonly called gametocidal effect of the chromosomes. The chromosome 2C of Ae. cylindrica is one of such chromosomes. In the present study, scab resistant wheat-L. racemosus addition lines involving chromosomes Lr.2 and Lr.7 were crossed to wheat-Ae. cylindrica disomic addition line Add2C. Then F1 hybrids were subsequently backcrossed with wheat cv "Chinese Spring". BC1 plants with chromosome structural aberration were identified by C-banding. In the self-pollinated progenies of these plants, three translocation lines were developed and characterized by mitotic and meiotic analysis combined with C-banding and fluorescent in situ hybridization (FISH) using biotin-labeled genomic DNA of L. racemosus as probe. Some other putative translocation lines to be further characterized were also found. The practicability and efficiency of the translocation between wheat and alien chromosomes induced by gametocidal chromosomes, as well as the potential use of the developed alien translocation lines were also discussed.

  10. Characterization of human PGD blastocysts with unbalanced chromosomal translocations and human embryonic stem cell line derivation?

    Science.gov (United States)

    Frydman, N; Féraud, O; Bas, C; Amit, M; Frydman, R; Bennaceur-Griscelli, A; Tachdjian, G

    2009-01-01

    Novel embryonic stem cell lines derived from embryos carrying structural chromosomal abnormalities obtained after preimplantation genetic diagnosis (PGD) are of interest to study in terms of the influence of abnormalities on further development. A total of 22 unbalanced blastocysts obtained after PGD were analysed for structural chromosomal defects. Morphological description and chromosomal status of these blastocysts was established and they were used to derive human embryonic stem cell (ESC) lines. An outgrowth of cells was observed for six blastocysts (6/22; 27%). For two blastocysts, the exact morphology was unknown since they were at early stage, and for four blastocysts, the inner cell mass was clearly visible. Fifteen blastocysts carried an unbalanced chromosomal defect linked to a reciprocal translocation, resulting in a positive outgrowth of cells for five blastocysts. One human ESC line was obtained from a blastocyst carrying a partial chromosome-21 monosomy and a partial chromosome-1 trisomy. Six blastocysts carried an unbalanced chromosomal defect linked to a Robertsonian translocation, and one showed a positive outgrowth of cells. One blastocyst carried an unbalanced chromosomal defect linked to an insertion and no outgrowth was observed. The efficiency of deriving human ESC lines with constitutional chromosomal disorders was low and probably depends on the initial morphological aspect of the blastocysts and/or the type of the chromosomal disorders.

  11. Molecular Cytogenetic Characterization of Wheat-Thinopyrum elongatum Addition, Substitution and Translocation Lines with a Novel Source of Resistance to Wheat Fusarium Head Blight

    Institute of Scientific and Technical Information of China (English)

    Shulan Fu; Zhenling Lv; Bao Qi; Xiang Guo; Jun Li; Bao Liu; Fangpu Han

    2012-01-01

    Thinopyrum elongatum (2n =2x =14,EE),a wild relative of wheat,has been suggested as a potentially novel source of resistance to several major wheat diseases including Fusarium Head Blight (FHB).In this study,a series of wheat (cv.Chinese Spring,CS) substitution and ditelosomic lines,including Th.elongatum additions,were assessed for Type Ⅱ resistance to FHB.Results indicated that the lines containing chromosome 7E of Th.elongatum gave a high level of resistance to FHB,wherein the infection did not spread beyond the inoculated floret.Furthermore,it was determined that the novel resistance gene(s) of 7E was located on the short-arm (7ES) based on sharp difference in FHB resistance between the two 7E ditelosomic lines for each arm.On the other hand,Th.elongatum chromosomes 5E and 6E likely contain gene(s) for susceptibility to FHB because the disease spreads rapidly within the inoculated spikes of these lines.Genomic in situ hybridization (GISH) analysis revealed that the alien chromosomes in the addition and substitution lines were intact,and the lines did not contain discernible genomic aberrations.GISH and multicolor-GISH analyses were further performed on three translocation lines that also showed high levels of resistance to FHB.Lines TA3499 and TA3695 were shown to contain one pair of wheat-Th.elongatum translocated chromosomes involving fragments of 7D plus a segment of the 7E,while line TA3493 was found to contain one pair of wheat-Th.elongatum translocated chromosomes involving the D- and A-genome chromosomes of wheat.Thus,this study has established that the short-arm of chromosome 7E of Th.elongatum harbors gene(s) highly resistant to the spreading of FHB,and chromatin of 7E introgressed into wheat chromosomes largely retained the resistance,implicating the feasibility of using these lines as novel material for breeding FHB-resistant wheat cultivars.

  12. Alterations and abnormal mitosis of wheat chromosomes induced by wheat-rye monosomic addition lines.

    Directory of Open Access Journals (Sweden)

    Shulan Fu

    Full Text Available BACKGROUND: Wheat-rye addition lines are an old topic. However, the alterations and abnormal mitotic behaviours of wheat chromosomes caused by wheat-rye monosomic addition lines are seldom reported. METHODOLOGY/PRINCIPAL FINDINGS: Octoploid triticale was derived from common wheat T. aestivum L. 'Mianyang11'×rye S. cereale L. 'Kustro' and some progeny were obtained by the controlled backcrossing of triticale with 'Mianyang11' followed by self-fertilization. Genomic in situ hybridization (GISH using rye genomic DNA and fluorescence in situ hybridization (FISH using repetitive sequences pAs1 and pSc119.2 as probes were used to analyze the mitotic chromosomes of these progeny. Strong pSc119.2 FISH signals could be observed at the telomeric regions of 3DS arms in 'Mianyang11'. However, the pSc119.2 FISH signals were disappeared from the selfed progeny of 4R monosomic addition line and the changed 3D chromosomes could be transmitted to next generation stably. In one of the selfed progeny of 7R monosomic addition line, one 2D chromosome was broken and three 4A chromosomes were observed. In the selfed progeny of 6R monosomic addition line, structural variation and abnormal mitotic behaviour of 3D chromosome were detected. Additionally, 1A and 4B chromosomes were eliminated from some of the progeny of 6R monosomic addition line. CONCLUSIONS/SIGNIFICANCE: These results indicated that single rye chromosome added to wheat might cause alterations and abnormal mitotic behaviours of wheat chromosomes and it is possible that the stress caused by single alien chromosome might be one of the factors that induced karyotype alteration of wheat.

  13. Production and cytogenetics of Brassica campestris-alboglabra chromosome addition lines

    DEFF Research Database (Denmark)

    Chen, B.Y.; Cheng, B.F.; Bagger Jørgensen, Rikke;

    1997-01-01

    Four different Brassica campestris-alboglabra monosomic addition lines (AA + 1 chromosome from C, 2n = 21) were obtained after consecutive backcrosses between resynthesized B. napus (AACC, 2n = 38) and the parental B. campestris (AA, 2n = 20) accession. The alien chromosomes of B. alboglabra (CC,...

  14. Mapping Heterotic Loci for Yield and Agronomic Traits Using Chromosome Segment Introgression Lines in Cotton

    Institute of Scientific and Technical Information of China (English)

    Xian Guo; Yuping Guo; Jun Ma; Fang Wang; Mizhen Sun; Lijuan Gui; Jiajia Zhou

    2013-01-01

    In the present study,a set of chromosome segment introgression lines (CSILs) using Gossypium hirsutum L.TM-1 as the recipient parent and G.barbadense Hai7124 as the donor parent were used to explore the genetic basis of heterosis for interspecific hybrids.Two sets of F1 populations individually derived from CSlLs crossing with both parents were configured to investigate heterotic loci (HL) and substitution effect loci (SL).A total of 58 HL and 39 SL were identified in 3 years.One stable HL,hLP-A4-3,could be detected in all 3 years.Three HLs,hBS-A8-1,hLP-D6-1,and hSI-D7-11,could be detected in 2 years.Four SLs,sBS-D7-1,sLP-A8-1,sLP-D7-1,and sLP-D12-1,could be detected in 2 years.HL and SL tended to be distributed in some HL-rich chromosome segments with close positions.Compared with QTL detected in a former study,HL showed little overlap with QTL,indicating that trait phenotype and heterosis might be controlled by different sets of loci.All three forms of genetic effects (partial-,full-,over-dominant) were identified,while the over-dominant effect made the main contribution to heterosis.These results may help lay the foundation for clarifying the heredity mechanism of heterosis in cotton.

  15. Chromosome

    Science.gov (United States)

    Chromosomes are structures found in the center (nucleus) of cells that carry long pieces of DNA. DNA ... is the building block of the human body. Chromosomes also contain proteins that help DNA exist in ...

  16. The Relationship Between Spontaneous Telomere Loss and Chromosome Instability in a Human Tumor Cell Line

    Directory of Open Access Journals (Sweden)

    Bijan Fouladi

    2000-01-01

    Full Text Available Chromosome instability plays an important role in cancer by promoting the alterations in the genome required for tumor cell progression. The loss of telomeres that protect the ends of chromosomes and prevent chromosome fusion has been proposed as one mechanism for chromosome instability in cancer cells, however, there is little direct evidence to support this hypothesis. To investigate the relationship between spontaneous telomere loss and chromosome instability in human cancer cells, clones of the EJ-30 tumor cell line were isolated in which a herpes simplex virus thymidine kinase (HSV-tk gene was integrated immediately adjacent to a telomere. Selection for HSV-tkdeficient cells with ganciclovir demonstrated a high rate of loss of the end these "marked" chromosomes (10-4 events/cell per generation. DNA sequence and cytogenetic analysis suggests that the loss of function of the HSV-tk gene most often involves telomere loss, sister chromatid fusion, and prolonged periods of chromosome instability. In some HSV-tk-deficient cells, telomeric repeat sequences were added on to the end of the truncated HSV-tk gene at a new location, whereas in others, no telomere was detected on the end of the marked chromosome. These results suggest that spontaneous telomere loss is a mechanism for chromosome instability in human cancer cells.

  17. Development of Mammalian Cell Lines with lac Operator-Tagged Chromosomes

    OpenAIRE

    sprotocols

    2014-01-01

    Authors: Yuri G. Strukov and Andrew S. Belmont This protocol was adapted from “Development of Mammalian Cell Lines with lac Operator-Tagged Chromosomes,” Chapter 25, in[ *Live Cell Imaging* ](http://www.cshlpress.com/link/livecelp.htm)(eds. Goldman and Spector). Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY, USA, 2005. ### INTRODUCTION The discovery and use of fluorescent proteins to label chromosomal proteins has yielded basic structural information as well as insig...

  18. Development and Molecular Cytogenetic Identification of a Novel Wheat-Leymus mollis Lm#7Ns (7D Disomic Substitution Line with Stripe Rust Resistance.

    Directory of Open Access Journals (Sweden)

    Xiaofei Yang

    Full Text Available Leymus mollis (2n = 4x = 28, NsNsXmXm possesses novel and important genes for resistance against multi-fungal diseases. The development of new wheat-L. mollis introgression lines is of great significance for wheat disease resistance breeding. M11003-3-1-15-8, a novel disomic substitution line of common wheat cv. 7182 -L. mollis, developed and selected from the BC1F5 progeny between wheat cv. 7182 and octoploid Tritileymus M47 (2n = 8x = 56, AABBDDNsNs, was characterized by morphological and cytogenetic identification, analysis of functional molecular markers, genomic in situ hybridization (GISH, sequential fluorescence in situ hybridization (FISH-genomic in situ hybridization (GISH and disease resistance evaluation. Cytological observations suggested that M11003-3-1-15-8 contained 42 chromosomes and formed 21 bivalents at meiotic metaphase I. The GISH investigations showed that line contained 40 wheat chromosomes and a pair of L. mollis chromosomes. EST-STS multiple loci markers and PLUG (PCR-based Landmark Unique Gene markers confirmed that the introduced L. mollis chromosomes belonged to homoeologous group 7, it was designated as Lm#7Ns. While nulli-tetrasomic and sequential FISH-GISH analysis using the oligonucleotide Oligo-pSc119.2 and Oligo-pTa535 as probes revealed that the wheat 7D chromosomes were absent in M11003-3-1-15-8. Therefore, it was deduced that M11003-3-1-15-8 was a wheat-L. mollis Lm#7Ns (7D disomic substitution line. Field disease resistance demonstrated that the introduced L. mollis chromosomes Lm#7Ns were responsible for the stripe rust resistance at the adult stage. Moreover, M11003-3-1-15-8 had a superior numbers of florets. The novel disomic substitution line M11003-3-1-15-8, could be exploited as an important genetic material in wheat resistance breeding programs and genetic resources.

  19. Chromosomal and Genetic Analysis of a Human Lung Adenocarcinoma Cell Line OM

    Institute of Scientific and Technical Information of China (English)

    Yong-Wu Li; Lin Bai; Lyu-Xia Dai; Xu He; Xian-Ping Zhou

    2016-01-01

    Background: Lung cancer has become the leading cause of death in many regions.Carcinogenesis is caused by the stepwise accumulation of genetic and chromosomal changes.The aim of this study was to investigate the chromosome and gene alterations in the human lung adenocarcinoma cell line OM.Methods: We used Giemsa banding and multiplex fluorescence in situ hybridization focusing on the human lung adenocarcinoma cell line OM to analyze its chromosome alterations.In addition, the gains and losses in the specific chromosome regions were identified by comparative genomic hybridization (CGH) and the amplifications of cancer-related genes were also detected by polymerase chain reaction (PCR).Results: We identified a large number of chromosomal numerical alterations on all chromosomes except chromosome X and 19.Chromosome 10 is the most frequently involved in translocations with six different interchromosomal translocations.CGH revealed the gains on chromosome regions of 3q25.3-28, 5p13, 12q22-23.24, and the losses on 3p25-26, 6p25, 6q26-27, 7q34-36, 8p22-23, 9p21-24, 10q25-26.3, 12p 13.31-13.33 and 17p 13.1-13.3.And PCR showed the amplification of genes: Membrane metalloendopeptidase (MME), sucrase-isomaltase (SI), butyrylcholinesterase (BCHE), and kininogen (KNG).Conclusions: The lung adenocarcinoma cell line OM exhibited multiple complex karyotypes, and chromosome 10 was frequently involved in chromosomal translocation, which may play key roles in tumorigenesis.We speculated that the oncogenes may be located at 3q25.3-28, 5p13, 12q22-23.24, while tumor suppressor genes may exist in 3p25-26, 6p25, 6q26-27, 7q34-36, 8p22-23, 9p21-24, 10q25-26.3, 12p 13.31-13.33, and 17p 13.1-13.3.Moreover, at least four genes (MME, SI, BCHE, and KNG) may be involved in the human lung adenocarcinoma cell line OM.

  20. Impacts of yttrium substitution on FMR line-width and magnetic properties of nickel spinel ferrites

    Energy Technology Data Exchange (ETDEWEB)

    Ishaque, M., E-mail: ishaqdgk1@gmail.com [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Khan, Muhammad Azhar, E-mail: azhar.khan@iub.edu.pk [Department of Physics, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Ali, Irshad; Khan, Hasan M. [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Iqbal, M. Asif [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); College of E & ME, National University of Science and Technology, Islamabad (Pakistan); Islam, M.U. [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Warsi, Muhammad Farooq [Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan)

    2015-05-15

    The influence of yttrium (Y) substitution on ferromagnetic resonance (FMR), initial permeability, and magnetic properties of NiFe{sub 2}O{sub 4} ferrites were investigated. It was observed that the FMR line-width decreases with yttrium contents for the substitution level 0≤×≤0.06. Beyond this, the FMR line-width increases with yttrium contents. The nominal composition NiY{sub 0.12}Fe{sub 1.88}O{sub 4} exhibited the smallest FMR line-width ~282 Oe. A significant change in FMR position of nickel–yttrium (Ni–Y) ferrites was observed and it found to exist between 4150 and 4600 Oe. The saturation magnetization was observed to decrease with the increase of yttrium contents and this was referred to the redistribution of cations on octahedral. The coercivity increased from 15 Oe to 59 Oe by increasing the yttrium concentration. The initial permeability decreased from 110 to 35 at 1 MHz by the incorporation of yttrium and this was attributed to the smaller grains which may obstruct the domain wall movement and impede the domain wall motion. The magnetic loss factors of substituted samples exhibit decreasing behavior in the frequency range 1 kHz to 10 MHz. The smaller FMR line-width and reduced magnetic loss factor of the investigated samples suggest the possible use of these materials in high frequency applications. - Highlights: • Influence of Y{sup 3+} substitution on the properties of nickel ferrites is investigated. • Very small FMR line-width (282 Oe) is exhibited by these substituted ferrites. • Fourfold increase in coercivity was observed for NiY{sub 0.24}Fe{sub 1.76}O{sub 4} ferrites.

  1. The microcell mediated transfer of human chromosome 8 into highly metastatic rat liver cancer cell line C5F

    Institute of Scientific and Technical Information of China (English)

    Hu Liu; Sheng-Long Ye; Jiong Yang; Zhao-You Tang; Yin-Kun Liu; Lun-Xiu Qin; Shuang-Jian Qiu; Rui-Xia Sun

    2003-01-01

    AIM: Our previous research on the surgical samples of primary liver cancer with CGH showed that the loss of human chromosome 8p had correlation with the metastatic phenotype of liver cancer. In order to seek the functional evidence that there could be a metastatsis suppressor gene (s) for liver cancer on human chromosome 8, we tried to transfer normal human chromosome 8 into rat liver cancer cell line C5F, which had high metastatic potential to lung.METHODS: Human chromosome 8 randomly marked with neo gene was introduced into C5F cell line by MMCT and positive microcell hybrids were screened by double selections of G418 and HAT. Single cell isolation cloning was applied to clone microcell hybrids. Finally, STS-PCR and WCP-FISH were used to confirm the introduction.RESULTS: Microcell hybrids resistant to HAT and G418 were obtained and 15 clones were obtained by single-cell isolation cloning. STS-PCR and WCP-FISH proved that human chromosome 8 had been successfully introduced into rat liver cancer cell line C5F. STS-PCR detected a random loss in the chromosome introduced and WCP-FISH found a consistent recombination of the introduced human chromosome with the rat chromosome.CONCLUSION: The successful introduction of human chromosome 8 into highly metastatic rat liver cancer cell line builds the basis for seeking functional evidence of a metastasis suppressor gene for liver cancer harboring on human chromosome 8 and its subsequent cloning.

  2. Anticancer Activities of Substituted Cinnamic Acid Phenethyl Esters on Human Cancer Cell Lines

    Institute of Scientific and Technical Information of China (English)

    LIShu-chun; LIHui; ZHANGFa; LIZhong-jun; CUIJing-rong

    2003-01-01

    Caffeic acid phenethyl ester (CAPE) and sixteen substituted cinnamic acid phenethyl esters were prepared via conventional procedures in order to test their in vitro anticancer activities by either MTT assay or SRB assay on six different human cancer cell lines. The results indicated that in the concentration of 10μmol·L-1 the lead compmuM CAPE possessed anficancer activities against human HL-60, Bel-7402, and Hela cell lines, and two other compounds possessed potent anticancer activities against Bel-7402 and Hela cell lines.

  3. Investigation of chromosome abnormalities and early embryonic mortality in goose lines.

    Science.gov (United States)

    Liptói, Krisztina; Hidas, A; Rouvier, R

    2005-01-01

    Early embryonic mortality and chromosome abnormalities were studied in three goose lines: Grey Landes (line 7), White Polish (line 4) and their synthetic line (line 9). Eggs laid at the beginning, in the middle and at the end of the laying season were set. At candling at 5th day after egg set, all eggs (2847) were examined and those showing no normal embryonic development were opened 2847. Dead embryos were classified phenotypically and karyotyped. The mean ratio of embryonic mortality (EM) among fertile eggs was 9.4%, 5.2%, 7.3% in the lines 4, 7 and 9, respectively. The mean ratio of embryos with chromosomal abnormalities (CA) among the dead embryos was 8.0%, 14.8% and 13.1% in the lines 4, 7 and 9, respectively. Gander effect and layer within gander effect on embryo mortality were significant, indicating genetic factors. Father and mother of the layer effects were also significant, showing family effects. Animals producing dead embryos and embryos with chromosome abnormalities in high proportion were selected. In the selected groups the mean EM was 17.7-22.9%, and the mean CA was 11.7-34.7% among the three lines. The repetition of CA was not observed in the reproductive season of following year, while animals repeated the high EM (repeatability coefficient of 0.54). This shows that some part of EM may be resulted from other genetic factors. Ganders and layers progeny of these selected animals showed also high EM. It was concluded that culling pairs giving high EM value in their embryos could increase the average level of embryo viability and that the study of genetic determinism of that trait should be continued in geese.

  4. A codon substitution model that incorporates the effect of the GC contents, the gene density and the density of CpG islands of human chromosomes

    Directory of Open Access Journals (Sweden)

    Misawa Kazuharu

    2011-08-01

    Full Text Available Abstract Background Developing a model for codon substitutions is essential for the analyses of protein sequences. Recent studies on the mutation rates in the non-coding regions have shown that CpG mutation rates in the human genome are negatively correlated to the local GC content and to the densities of functional elements. This study aimed at understanding the effect of genomic features, namely, GC content, gene density, and frequency of CpG islands, on the rates of codon substitution in human chromosomes. Results Codon substitution rates of CpG to TpG mutations, TpG to CpG mutations, and non-CpG transitions and transversions in humans were estimated by comparing the coding regions of thousands of human and chimpanzee genes and inferring their ancestral sequences by using macaque genes as the outgroup. Since the genomic features are depending on each other, partial regression coefficients of these features were obtained. Conclusion The substitution rates of codons depend on gene densities of the chromosomes. Transcription-associated mutation is one such pressure. On the basis of these results, a model of codon substitutions that incorporates the effect of genomic features on codon substitution in human chromosomes was developed.

  5. TP53-dependent chromosome instability is associated with transient reductions in telomere length in immortal telomerase-positive cell lines

    Science.gov (United States)

    Schwartz, J. L.; Jordan, R.; Liber, H.; Murnane, J. P.; Evans, H. H.

    2001-01-01

    Telomere shortening in telomerase-negative somatic cells leads to the activation of the TP53 protein and the elimination of potentially unstable cells. We examined the effect of TP53 gene expression on both telomere metabolism and chromosome stability in immortal, telomerase-positive cell lines. Telomere length, telomerase activity, and chromosome instability were measured in multiple clones isolated from three related human B-lymphoblast cell lines that vary in TP53 expression; TK6 cells express wild-type TP53, WTK1 cells overexpress a mutant form of TP53, and NH32 cells express no TP53 protein. Clonal variations in both telomere length and chromosome stability were observed, and shorter telomeres were associated with higher levels of chromosome instability. The shortest telomeres were found in WTK1- and NH32-derived cells, and these cells had 5- to 10-fold higher levels of chromosome instability. The primary marker of instability was the presence of dicentric chromosomes. Aneuploidy and other stable chromosome alterations were also found in clones showing high levels of dicentrics. Polyploidy was found only in WTK1-derived cells. Both telomere length and chromosome instability fluctuated in the different cell populations with time in culture, presumably as unstable cells and cells with short telomeres were eliminated from the growing population. Our results suggest that transient reductions in telomere lengths may be common in immortal cell lines and that these alterations in telomere metabolism can have a profound effect on chromosome stability. Copyright 2000 Wiley-Liss, Inc.

  6. Deletion and translocation of chromosome 11q13 sequences in cervical carcinoma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Jesudasan, R.A.; Srivatsan, E.S. [UCLA School of Medicine, CA (United States); Rahman, R.A. [Clinical Genetics Center, La Mirada, CA (United States); Chandrashekharappa, S. [National Center for Human Genome Research, Bethesda, MD (United States); Evans, G.A. [Univ. of Texas Southwestern Medical Center, Dallas, TX (United States)

    1995-03-01

    Molecular genetic studies on HeLa cell-derived nontumorigenic and tumorigenic hybrids have previously localized the HeLa cell tumor-suppressor gene to the long arm of chromosome 11. Extensive molecular and cytogenetic studies on HeLa cells have shown chromosome band 11q13 to be rearranged in this cell line. To determine whether q13 rearrangement is a nonrandom event in cervical carcinomas, six different human papilloma virus (HPV)-positive (HeLa, SiHa, Caski, C4-I, Me180, and Ms751) and two different HPV-negative (C33A and HT3) cell lines were studied. Long-range restriction mapping using a number of q13-specific probes showed molecular arrangements within 75 kb of INT2 probe in three HPV-positive cell lines (HeLa, SiHa, and Caski) and in an HPV-negative cell line (HT3). FISH using an INT2 YAC identified a breakpoint within the sequences spanned by this YAC in two of the cell lines, HeLa and Caski. INT2 cosmid derived from this YAC showed deletion of cosmid sequences in two other cell lines, SiHa and C33A. These two cell lines, however, retained cosmid sequences of Cyclin D1, a probe localized 100 kb proximal to INT2. Deletions being the hallmark of a tumor-suppressor gene, we conclude that the 100-kb interval between the two cosmids might contain sequences of the cervical carcinoma tumor-suppressor gene. 28 refs., 9 figs.

  7. Integration sites of Epstein-Barr virus genome on chromosomes of human lymphoblastoid cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Wuu, K.D.; Chen, Y.J.; Wang-Wuu, S. [Institute of Genetics, Taipei (Taiwan, Province of China)

    1994-09-01

    Epstein-Barr virus (EBV) is the pathogen of infectious mononucleosis. The viral genome is present in more than 95% of the African cases of Burkitt lymphoma and it is usually maintained in episomal form in the tumor cells. Viral integration has been described only for Nanalwa which is a Burkitt lymphoma cell line lacking episomes. In order to examine the role of EBV in the immortalization of human Blymphocytes, we investigated whether the EBV integration into the human genome is essential. If the integration does occur, we would like to know whether the integration is randomly distributed or whether the viral DNA integrates preferentially at certain sites. Fourteen in vitro immortalized human lymphoblastoid cell lines (LCLs) were examined by fluorescence in situ hybridization (FISH) with a biotinylated EBV BamHI w DNA fragment as probe. The episomal form of EBV DNA was found in all cells of these cell lines, while only about 65% of the cells have the integrated viral DNA. This might suggest that integration is not a pre-requisite for cell immortalization. Although all chromosomes, except Y, have been found with integrated viral genome, chromsomes 1 and 5 are the most frequent EBV DNA carrier (p<0.05). Nine chromosome bands, namely, 1p31, 1q31, 2q32, 3q13, 3q26, 5q14, 6q24, 7q31 and 12q21, are preferential targets for EBV integration (p<0.001). Eighty percent of the total 938 EBV hybridization signals were found to be at G-band-positive area. This suggests that the mechanism of EBV integration might be different from that of the retroviruses, which specifically integrate to G-band-negative areas. Thus, we conclude that the integration of EBV to host genome is non-random and it may have something to do with the structure of chromosome and DNA sequences.

  8. Genetic dissection of tetraploid cotton resistant to Verticillium wilt using interspecific chromosome segment introgression lines

    Institute of Scientific and Technical Information of China (English)

    Peng; Wang; Zhiyuan; Ning; Ling; Lin; Hong; Chen; Hongxian; Mei; Jun; Zhao; Bingliang; Liu; Xin; Zhang; Wangzhen; Guo; Tianzhen; Zhang

    2014-01-01

    Verticillium wilt(caused by the pathogen Verticillium dahliae) is of high concern for cotton producers and consumers. The major strategy for controlling this disease is the development of resistant cotton(Gossypium spp.) cultivars. We used interspecific chromosome segment introgression lines(CSILs) to identify quantitative trait loci(QTL) associated with resistance to Verticillium wilt in cotton grown in greenhouse and inoculated with three defoliating V. dahliae isolates. A total of 42 QTL, including 23 with resistance-increasing and 19 with resistancedecreasing, influenced host resistance against the three isolates. These QTL were identified and mapped on 18 chromosomes(chromosomes A1, A3, A4, A5, A7, A8, A9, A12, A13, D1, D2,D3, D4, D5, D7, D8, D11, and D12), with LOD values ranging from 3.00 to 9.29. Among the positive QTL with resistance-increasing effect, 21 conferred resistance to only one V. dahliae isolate, suggesting that resistance to V. dahliae conferred by most QTL is pathogen isolate-specific. The At subgenome of cotton had greater effect on resistance to Verticillium wilt than the Dt subgenome. We conclude that pyramiding different resistant QTL could be used to breed cotton cultivars with broad-spectrum resistance to Verticillium wilt.

  9. X chromosome inactivation and Xist evolution in a rodent lacking LINE-1 activity.

    Science.gov (United States)

    Cantrell, Michael A; Carstens, Bryan C; Wichman, Holly A

    2009-07-15

    Dosage compensation in eutherian mammals occurs by inactivation of one X chromosome in females. Silencing of that X chromosome is initiated by Xist, a large non-coding RNA, whose coating of the chromosome extends in cis from the X inactivation center. LINE-1 (L1) retrotransposons have been implicated as possible players for propagation of the Xist signal, but it has remained unclear whether they are essential components. We previously identified a group of South American rodents in which L1 retrotransposition ceased over 8 million years ago and have now determined that at least one species of these rodents, Oryzomys palustris, still retains X inactivation. We have also isolated and analyzed the majority of the Xist RNA from O. palustris and a sister species retaining L1 activity, Sigmodon hispidus, to determine if evolution in these sequences has left signatures that might suggest a critical role for L1 elements in Xist function. Comparison of rates of Xist evolution in the two species fails to support L1 involvement, although other explanations are possible. Similarly, comparison of known repeats and potential RNA secondary structures reveals no major differences with the exception of a new repeat in O. palustris that has potential to form new secondary structures.

  10. Construction of BAC-based physical map and analysis of chromosome rearrangement in Chinese hamster ovary cell lines.

    Science.gov (United States)

    Cao, Yihua; Kimura, Shuichi; Itoi, Takayuki; Honda, Kohsuke; Ohtake, Hisao; Omasa, Takeshi

    2012-06-01

    Chinese hamster ovary (CHO) cells have frequently been used in biotechnology for many years as a mammalian host cell platform for cloning and expressing genes of interest. A detailed physical chromosomal map of the CHO DG44 cell line was constructed by fluorescence in situ hybridization (FISH) imaging using randomly selected 303 BAC clones as hybridization probes (BAC-FISH). The two longest chromosomes were completely paired chromosomes; other chromosomes were partly deleted or rearranged. The end sequences of 624 BAC clones, including 287 mapped BAC clones, were analyzed and 1,119 informative BAC end sequences were obtained. Among 303 mapped BAC clones, 185 clones were used for BAC-FISH analysis of CHO K1 chromosomes and 94 clones for primary Chinese hamster lung cells. Based on this constructed physical map and end sequences, the chromosome rearrangements between CHO DG44, CHO K1, and primary Chinese hamster cells were investigated. Among 20 CHO chromosomes, eight were conserved without large rearrangement in CHO DG44, CHO K1, and primary Chinese hamster cells. This result suggested that these chromosomes were stable and essential in CHO cells and supposedly conserved in other CHO cell lines.

  11. Transcriptomic analysis of fiber strength in upland cotton chromosome introgression lines carrying different Gossypium barbadense chromosomal segments.

    Directory of Open Access Journals (Sweden)

    Lei Fang

    Full Text Available Fiber strength is the key trait that determines fiber quality in cotton, and it is closely related to secondary cell wall synthesis. To understand the mechanism underlying fiber strength, we compared fiber transcriptomes from different G. barbadense chromosome introgression lines (CSILs that had higher fiber strengths than their recipient, G. hirsutum acc. TM-1. A total of 18,288 differentially expressed genes (DEGs were detected between CSIL-35431 and CSIL-31010, two CSILs with stronger fiber and TM-1 during secondary cell wall synthesis. Functional classification and enrichment analysis revealed that these DEGs were enriched for secondary cell wall biogenesis, glucuronoxylan biosynthesis, cellulose biosynthesis, sugar-mediated signaling pathways, and fatty acid biosynthesis. Pathway analysis showed that these DEGs participated in starch and sucrose metabolism (328 genes, glycolysis/gluconeogenesis (122 genes, phenylpropanoid biosynthesis (101 genes, and oxidative phosphorylation (87 genes, etc. Moreover, the expression of MYB- and NAC-type transcription factor genes were also dramatically different between the CSILs and TM-1. Being different to those of CSIL-31134, CSIL-35431 and CSIL-31010, there were many genes for fatty acid degradation and biosynthesis, and also for carbohydrate metabolism that were down-regulated in CSIL-35368. Metabolic pathway analysis in the CSILs showed that different pathways were changed, and some changes at the same developmental stage in some pathways. Our results extended our understanding that carbonhydrate metabolic pathway and secondary cell wall biosynthesis can affect the fiber strength and suggested more genes and/or pathways be related to complex fiber strength formation process.

  12. Transcriptomic analysis of fiber strength in upland cotton chromosome introgression lines carrying different Gossypium barbadense chromosomal segments.

    Science.gov (United States)

    Fang, Lei; Tian, Ruiping; Chen, Jiedan; Wang, Sen; Li, Xinghe; Wang, Peng; Zhang, Tianzhen

    2014-01-01

    Fiber strength is the key trait that determines fiber quality in cotton, and it is closely related to secondary cell wall synthesis. To understand the mechanism underlying fiber strength, we compared fiber transcriptomes from different G. barbadense chromosome introgression lines (CSILs) that had higher fiber strengths than their recipient, G. hirsutum acc. TM-1. A total of 18,288 differentially expressed genes (DEGs) were detected between CSIL-35431 and CSIL-31010, two CSILs with stronger fiber and TM-1 during secondary cell wall synthesis. Functional classification and enrichment analysis revealed that these DEGs were enriched for secondary cell wall biogenesis, glucuronoxylan biosynthesis, cellulose biosynthesis, sugar-mediated signaling pathways, and fatty acid biosynthesis. Pathway analysis showed that these DEGs participated in starch and sucrose metabolism (328 genes), glycolysis/gluconeogenesis (122 genes), phenylpropanoid biosynthesis (101 genes), and oxidative phosphorylation (87 genes), etc. Moreover, the expression of MYB- and NAC-type transcription factor genes were also dramatically different between the CSILs and TM-1. Being different to those of CSIL-31134, CSIL-35431 and CSIL-31010, there were many genes for fatty acid degradation and biosynthesis, and also for carbohydrate metabolism that were down-regulated in CSIL-35368. Metabolic pathway analysis in the CSILs showed that different pathways were changed, and some changes at the same developmental stage in some pathways. Our results extended our understanding that carbonhydrate metabolic pathway and secondary cell wall biosynthesis can affect the fiber strength and suggested more genes and/or pathways be related to complex fiber strength formation process.

  13. Characterization of T. aestivum-H, californicum chromosome addition lines DA2H and MA5H

    Institute of Scientific and Technical Information of China (English)

    Fang Kong; Haiyan Wang; Aizhong Cao; Bi Qin; Jianhui Ji; Suling Wang; Xiu-E Wang

    2008-01-01

    In order to transfer useful genes of Hordeum californicum into common wheat (Triticum aestivum L.), the T. aestivum c.v. Chinese Spring (CS)-H. californicum amphiploid was crossed to CS, and its backcrossing and self-fertilized progenies were analyzed by morpho-logical observation, cytological, biochemical and molecular marker techniques. Alien addition lines with two H. californicum chromo-somes were identified and their genetic constitution was characterized. STS-PCR analysis using chromosome 2B specific markers indi-cated that chromosome H3 of 1t. califomicum belongs to homoeologous group 2, and was thus designated 2H. SDS-PAGE showed that chromosome H2 of H. californicum belongs to homoeologous group 5, and was designated 5H. The CS-H. californicum amphiploid and the chromosome addition lines (DA2H and MA5H) identified were evaluated for powdery mildew (Erysiphe graminis f. sp. triticii) resis-tance in field. The preliminary results indicated that the amphiploid showed higher powdery mildew resistance than CS. However, chro-mosome addition lines DA2H and MA5H were highly susceptible to powdery mildew, indicating that major powdery mildew resistant genes of H. californicum should be located on chromosomes other than 2H and 5H.

  14. Inducement of chromosome translocation with small alien segments by irradiating mature female gametes of the whole arm translocation line

    Institute of Scientific and Technical Information of China (English)

    CHEN ShengWei; CHEN PeiDu; WANG XiuE

    2008-01-01

    Haynaldia villosa Schur. (syn. Dasypyrum villosum Candargy, 2n=14, VV) has been proved to be an Important genetic resource for wheat improvement. The development of translocation with small alien chromosome segments, especially interstitial translocation, will be helpful for better utilization of its useful genes. Up to now, most of the reported Triticum aestivum - H. villosa translocation lines are involved in a whole arm or large alien fragments. In this paper, we report a highly efficient approach for the creation of small chromosome segment translocation lines. Before flowering, the female gametes of wheat-H, villosa 6VS/6AL trsnslocation line were irradiated by 60Co-γ ray at 160 Rad/M dosage rate and three dosages (1600, 1920, 2240 Rad). Anthers were removed from the irradiated florets on the same day and the florets were pollinated with normal fresh pollens of T. aestivum cv. Chinese Spring after 2-3 days. Genomic in situ hybridization (GISH) at mitosis metaphase of root-tip cell of M1 plants was used to detect the chromosome structural changes involving 6VS of H. villosa. Among the 534 M1 plants screened, 97 plants contained small segment chromosome structural changes of 6VS, including 80 interstitial translocation chromosomes, 57 terminal translocation chromosomes and 55 deletion chromosomes. For the 2240 Rad dosage treatment, the inducement frequencies of interstitial translocation, terminal translocation and deletion were 21.02%, 14.01%, and 14.65%, respectively, which were much higher than those previously reported. The M2 seeds were obtained by bsckcrossing of 74 M1 plants involving 146 chromosomes structural changes of 6VS, and it was found that the structural aberrations in the M1 plants could be transmitted to their progenies. Irradiating mature female gametes of whole arm translocation is a new and highly efficient approach for creation of small segment chromosome structural changes, especially for interstitial translocations.

  15. Inducement of chromosome translocation with small alien segments by irradiating mature female gametes of the whole arm translocation line

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Haynaldia villosa Schur. (syn. Dasypyrum villosum Candargy, 2n=14, VV) has been proved to be an important genetic resource for wheat improvement. The development of translocation with small alien chromosome segments, especially interstitial translocation, will be helpful for better utilization of its useful genes. Up to now, most of the reported Triticum aestivum – H. villosa translocation lines are involved in a whole arm or large alien fragments. In this paper, we report a highly efficient approach for the creation of small chromosome segment translocation lines. Before flowering, the female gametes of wheat-H. villosa 6VS/6AL translocation line were irradiated by 60CO-γ ray at 160 Rad/M dosage rate and three dosages (1600, 1920, 2240 Rad). Anthers were removed from the irradiated florets on the same day and the florets were pollinated with normal fresh pollens of T. aestivum cv. Chinese Spring after 2-3 days. Genomic in situ hybridization (GISH) at mitosis metaphase of root-tip cell of M1 plants was used to detect the chromosome structural changes involving 6VS of H. villosa. Among the 534 M1 plants screened, 97 plants contained small segment chromosome structural changes of 6VS, including 80 interstitial translocation chromosomes, 57 terminal translocation chromosomes and 55 deletion chromosomes. For the 2240 Rad dosage treatment, the inducement frequencies of interstitial translo-cation, terminal translocation and deletion were 21.02%, 14.01%, and 14.65%, respectively, which were much higher than those previously reported. The M2 seeds were obtained by backcrossing of 74 M1 plants involving 146 chromosomes structural changes of 6VS, and it was found that the structural aberrations in the M1 plants could be transmitted to their progenies. Irradiating mature female gametes of whole arm translocation is a new and highly efficient approach for creation of small segment chromosome struc-tural changes, especially for interstitial translocations.

  16. Interspecific Chromosome Substitution Lines as Genetic Resources for Improvement,Trait Analysis and Genomic Inference

    Institute of Scientific and Technical Information of China (English)

    RASKA Dwaine A; SAHA Sukumar; JENKINS Johnie N; MCCARTY Jack C; WU Ji-xiang; STELLY David M

    2008-01-01

    @@ The genetic base that cotton breeders commonly use to improve Upland cultivars is very narrow.The AD-genome species Gossypium barbadense,G.tomentosum,and G.mustelinum are part of the primary germplasm pool,too,and constitute genetic reservoirs of genes for resistance to abiotic stress,pests,and pathogens,as well as agronomic and fiber traits.

  17. Construction of six Oryza sativa x O. rufipogon Chromosome Segment Substitution Line (CSSL) Libraries

    Science.gov (United States)

    Transgressive variation has been observed in rice (Oryza sativa) as an increase in grain yield and attributed to the ancestral parent, O. rufipogon, in mapping populations developed from several adapted rice varieties crossed with a single O. rufipogon accession. To explore this phenomenon of transg...

  18. Deletion breakpoint mapping on chromosome 9p21 in breast cancer cell line MCF-7

    Directory of Open Access Journals (Sweden)

    Hua-ping XIE

    2012-05-01

    Full Text Available Objective  To map the deletion breakpoint of chromosome 9p21 in breast cancer cell line MCF-7. Methods  The deletion of chromosome 9p21 was checked by Multiplex Ligation-dependent Probe Amplification (MLPA in MCF-7. Subsequently, the deletion breakpoint was amplified by long range PCR and the deletion region was narrowed by primer walking. Finally, the deletion position was confirmed by sequencing. Results  The deletion was found starting within the MTAP gene and ending within CDKN2A gene by MLPA. Based on long range PCR and primer walking, the deletion was confirmed to cover the region from chr9:21819532 to chr9:21989622 by sequencing, with a deletion size of 170kb, starting within the intron 4 of MTAP and ending within the intron 1 near exon 1β of CDKN2A. Conclusions  Long range PCR is an efficient way to detect deletion breakpoints. In MCF-7, the deletion has been confirmed to be 170kb, starting within the MTAP gene and ending within the CDKN2A gene. The significance of the deletion warrants further research.

  19. Identification of Wheat-Barley 2H Alien Substitution Lines%小麦-大麦2H异代换系的鉴定

    Institute of Scientific and Technical Information of China (English)

    原亚萍; 陈孝; 肖世和; A.K.M.R.ISLAM; 辛志勇

    2003-01-01

    通过基因组原位杂交、重双端体测交及RFLP分析,解析了来自小麦品种"中国春"(Triticum aestivumL.cv."Chinese Spring"(CS))×大麦品种"Betzes"(Hordeum vulgare L.cv."Betzes")杂种后代15份材料的遗传组成,鉴定出6个二体异代换系;对与"中国春"重双端体DDT2A、DDT2B及DDT2D测交的F1代花粉母细胞减数分裂中期染色体构型进行观察,同时以小麦第二部分同源群短臂探针psr131进行RFLP分析,鉴定出一套遗传稳定的小麦-大麦2H二体异代换系2H(A)、2H(B)和2H(D).小麦第二部分同源群短臂探针psr131可作为追踪大麦2H染色体的RFLP标记.从代换系的生长势及其他农艺性状看,大麦2H染色体对小麦染色体2B和2D的补偿作用较好.通过考种观察到携带大麦α淀粉酶抑制蛋白基因的2H染色体导入小麦后,淀粉品质发生了改变,外观品质由原来"中国春"的半粉质转变为代换系的半角质.%The genetic constitution of fifteen materials derived from the cross wheat ( Triticum aestivum L. cv. "Chinese Spring") × barley (Hordeum vulgare L. cv. "Betzes") was analyzed, and six disomic aliensubstitution lines were screened by GISH. The chromosome configurations in pollen mother cells atmeiotic metaphase Ⅰ (PMCs M I ) of F1 from each disomic substitution line respectively crossed withdouble ditelocentric lines 2A, 2B and 2D of "Chinese Spring" were observed, and a set of wheat-barleydisomic alien substitution lines 2H(A), 2H(B) and 2H(D) were obtained. The RFLP analysis with the probepsr131 on the short arm of wheat homeologous group 2 combining with four restriction enzymes werecarried out. The results indicated that the probe psr131 could be used as molecular marker to tag thebarley chromosome 2H. The barley chromosome 2H had good genetic compensation ability for wheatchromosomes 2B and 2D in vitality and other agronomic characters. The result of testing seed was thatthe wheat appearance starch quality had been changed

  20. Unconditional and Conditional QTL Mapping for Tiller Numbers at Various Stages with Single Segment Substitution Lines in Rice (Oryza sativa L.)

    Institute of Scientific and Technical Information of China (English)

    ZHAO Fang-ming; LIU Gui-fu; ZHU Hai-tao; DING Xiao-hua; ZENG Rui-zhen; ZHANG Ze-min; LI Wen-tao; ZHANG Gui-quan

    2008-01-01

    Tiller is one of the most important agronomic traits which influences quantity and quality of effective panicles and finally influences yield in rice.It is important to understand "static" and "dynamic" information of the QTLs for tillers in rice.This work was the first time to simultaneously map unconditional and conditional QTLs for tiller numbers at various stages by using single segment substitution lines in rice.Fourteen QTLs for tiller number,distributing on the corresponding substitution segments of chromosomes 1,2,3,4,6,7 and 8 were detected.Both the number and the effect of the QTLs for tiller number were various at different stages,from 6 to 9 in the number and from 1.49 to 3.49 in the effect,respectively. Tiller number QTLs expressed in a time order,mainly detected at three stages of 0-7d,14-21d and 35-42d after transplanting with 6 positive,9 random and 6 negative expressing QTLs,respectively.Each of the QTLs expressed one time at least during the whole duration of rice.The tiller number at a specific stage was determined by sum of QTL effects estimated by the unconditional method,while the increasing or decreasing number in a given time interval was controlled by the total of QTL effects estimated by the conditional method.These results demonstrated that it is highly effective and accurate for mapping of the QTLs by using single segment substitution lines and the conditional analysis methodology.

  1. Dynamic Investigation on Chromosome Aberration of a Human Retinoblastoma Cell Line SO-Rb_(50)

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    G-banding and karyotype analyses of cells in seventeen passages of SO-Rb_(50) during a long period of culture for about four years were performed. Three chromosome markers 13q14~-, 1p36~+ and 12p13~+ were found. Cells possessed 13q14~- reduced to zero after the 200th passage while 1p~+ and 12p~+ cells increased to 100% after 30 and 200 passages respectively. Abnormal chromosomes, ring chromosomes, chromosome radiuses and double minutes were also observed. These chromosomal changes were more often seen b...

  2. On-line reaction monitoring of lithiation of halogen substituted acetanilides via in situ calorimetry, ATR spectroscopy, and endoscopy.

    Science.gov (United States)

    Godany, Tamas A; Neuhold, Yorck-Michael; Hungerbühler, Konrad

    2011-01-01

    Lithiation of N-(4-chlorophenyl)-pivalamide (NCP) and two additional substituted acetanilides: 4-fluoroacetanilide (4-F) and 4-chloroacetanilide (4-Cl) has been monitored by means of calorimetry, on-line ATR-IR and UV/vis spectroscopy and endoscopy. The combined on-line monitoring revealed the differences between the reaction paths of the chosen substrates. Thus the product structure and the reaction times for the individual reaction steps can be determined in situ.

  3. Introgression of chromosome segments from multiple alien species in wheat breeding lines with wheat streak mosaic virus resistance.

    Science.gov (United States)

    Ali, N; Heslop-Harrison, Js Pat; Ahmad, H; Graybosch, R A; Hein, G L; Schwarzacher, T

    2016-08-01

    Pyramiding of alien-derived Wheat streak mosaic virus (WSMV) resistance and resistance enhancing genes in wheat is a cost-effective and environmentally safe strategy for disease control. PCR-based markers and cytogenetic analysis with genomic in situ hybridisation were applied to identify alien chromatin in four genetically diverse populations of wheat (Triticum aestivum) lines incorporating chromosome segments from Thinopyrum intermedium and Secale cereale (rye). Out of 20 experimental lines, 10 carried Th. intermedium chromatin as T4DL*4Ai#2S translocations, while, unexpectedly, 7 lines were positive for alien chromatin (Th. intermedium or rye) on chromosome 1B. The newly described rye 1RS chromatin, transmitted from early in the pedigree, was associated with enhanced WSMV resistance. Under field conditions, the 1RS chromatin alone showed some resistance, while together with the Th. intermedium 4Ai#2S offered superior resistance to that demonstrated by the known resistant cultivar Mace. Most alien wheat lines carry whole chromosome arms, and it is notable that these lines showed intra-arm recombination within the 1BS arm. The translocation breakpoints between 1BS and alien chromatin fell in three categories: (i) at or near to the centromere, (ii) intercalary between markers UL-Thin5 and Xgwm1130 and (iii) towards the telomere between Xgwm0911 and Xbarc194. Labelled genomic Th. intermedium DNA hybridised to the rye 1RS chromatin under high stringency conditions, indicating the presence of shared tandem repeats among the cereals. The novel small alien fragments may explain the difficulty in developing well-adapted lines carrying Wsm1 despite improved tolerance to the virus. The results will facilitate directed chromosome engineering producing agronomically desirable WSMV-resistant germplasm.

  4. Experimental Researches on Carcinogenesis or Tumorigenicity of MDCK Canine Kidney Cell(CKC) Lines and Analysis of Their Chromosome Karyotypes

    Institute of Scientific and Technical Information of China (English)

    ZHANG De-li; FANG Fu-de; LI Liu-jin; XIA Geng-tian; HE Xu-yu; GAO Bu-xian; BAI Xiao-hong; HUANG Gao-sheng; LIU Shang-gao; YAN Long-fei

    2002-01-01

    The chromosomal number variations & structural aberrations of the MDCK cell line, primary feline or canine kidney cell(FKC or CKC) and Hela cell line were investigated and their karyotypes of conventional chromosome bands were analyzed. The carcinogenesis or tumorigenicity testing of these cell lines in about 232 nude mice and for colony formation in soft agarose and for haemagglutination under different concentration of plant lectins of these cells were carried out. Under the prerequisite that the incidence of cancer or tumor in negative-control nude mice inoculated subcutaneously with primary feline or canine kidney cell cultures purified in vitro at passage 3 was 0 (0/22) and 0 (0/10), respectively. The incidence of the progressively-growing malignant tumor(MT) in positive-control nude mice inoculated subcutaneously with Hela cell cultures of KB, X, or NM20/X strain was 10/10, 25/25 and 5/51, respectively. The results showed that the incidence of tumor in nude mice with tetrapioid YA strain of MDCK cell during 20 - 45 passages, with hypodiploid JB strain of MDCK cell on passage 25, with di-and hypoploid JC strain of MDCK cell during 2 - 15passages or with hypoploid M strain of MDCK cell during 9 - 27 passages was 28/58, 1/5, 4/18 and 0/31,respectively. The chromosomal analysis results showed that the ratio of difference in the rate of modal chromosome number between high (mcs + n) and lowest (mcs)passages was not more than 5 % - 15 % and the structure aberrations was generally 0 - 3%. These results proved that the genetic characteristics of chromosomal number of cell lines determines their tumorigenicity, but it is species-specific. MDCK line has tumorigenicity no matter what its chromosome karyotype is, at least it has very low tumorigenicity even when its modal chromosome number is hypoploid. The repeatedly frozen, thawed and split controls of tumorigenicity-positive cell lines(X strain of Hela, M strain of BHK-21, JA strain of Vero, YA strain of MDCK) have

  5. [Investigation of chromosomes in varieties and translocation lines of pea Pisum sativum L. by FISH, Ag-NOR, and differential DAPI staining].

    Science.gov (United States)

    Samatadze, T E; Muravenko, O M; Bol'sheva, N L; Amosova, A B; Gostimsckiĭ, S A; Zelenin, A V

    2005-12-01

    The DNA intercalator 9-aminoachridine was used for obtaining high-resolution DAPI patterns of chromosomes of Pisum sativum L. with more than 300 bands per haploid chromosome set. The karyotypes of three pea varieties, Viola, Capital, and Rosa Crown, and two translocation lines, L-108 (T(2-4s)) and M-10 (T(2-7s)), were examined. Based on the results of DAPI staining, we have identified chromosomes, constructed idiograms, and established breakpoints of chromosome translocations. Lines L-108 (T(2-4s)) and M-10 (T(2-7s)) were shown to appear as a result of respectively one translocation between chromosomes 2 and 4 and two translocations between chromosomes 2 and 7. All varieties and translocation lines of pea were examined using fluorescence in situ hybridization (FISH) with telomere repetition probes, 5S and 45S wheat DNA probes. Transcriptional activity of 45S rRNA was detected by Ag-NOR staining. Telomere repetitions were shown to be located only in telomeric chromosome regions. Using high-resolution DAPI staining allowed us to verify localization of 5S genes on pea chromosomes 1, 3, and 5. 45S rDNAs were localized in the secondary constriction regions on the satellite and the satellite thread of chromosome and on the satellite thread and in more proximal satellite heterochromatic region of chromosome 7. The size of 45S rDNA signal on chromosome 7 was larger and its transcriptional activity, higher than the corresponding parameters on chromosome 4 in most of the forms studied. A visual comparison of the results of FISH and Ag-NOR staining of normal and translocated pea chromosomes did not reveal any significant differences between them. The translocations of the satellite chromosomes apparently did not cause significant changes either in the amount of the ribosomal genes or in their transcriptional activity.

  6. Identification and Investigation of Native Chromosomal Fragile Sites in the Avian Cell Line DT40

    DEFF Research Database (Denmark)

    Pentzold, Constanze

    Chromosomal fragile sites are a cytogenetic phenomenon of genome instability that manifests in gaps or breaks on metaphase chromosomes. Diverse mechanisms are involved in their expression but all of them originate from the idea of replication impairment as the main driver for fragility. Cellular ...... kingdom....

  7. Cytogenetic Characterization of the TM4 Mouse Sertoli Cell Line. II. Chromosome Microdissection, FISH, Scanning Electron Microscopy, and Confocal Laser Scanning Microscopy.

    Science.gov (United States)

    Schmid, Michael; Guttenbach, Martina; Steinlein, Claus; Wanner, Gerhard; Houben, Andreas

    2015-01-01

    The chromosomes and interphase cell nuclei of the permanent mouse Sertoli cell line TM4 were examined by chromosome microdissection, FISH, scanning electron microscopy, and confocal laser scanning microscopy. The already known marker chromosomes m1-m5 were confirmed, and 2 new large marker chromosomes m6 and m7 were characterized. The minute heterochromatic marker chromosomes m4 and m5 were microdissected and their DNA amplified by DOP-PCR. FISH of this DNA probe on TM4 metaphase chromosomes demonstrated that the m4 and m5 marker chromosomes have derived from the centromeric regions of normal telocentric mouse chromosomes. Ectopic pairing of the m4 and m5 marker chromosomes with the centromeric region of any of the other chromosomes (centromeric associations) was apparent in ∼60% of the metaphases. Scanning electron microscopy revealed DNA-protein bridges connecting the centromeric regions of normal chromosomes and the associated m4 and m5 marker chromosomes. Interphase cell nuclei of TM4 Sertoli cells did not exhibit the characteristic morphology of Sertoli cells in the testes of adult mice as shown by fluorescence microscopy and confocal laser scanning microscopy.

  8. Introgression of Resistance to Powdery Mildew Conferred by Chromosome 2R by Crossing Wheat Nullisomic 2D with Rye

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Using the nullisomic back-cross procedure, four wheat-rye chromosome substitution 2R (2D) lines with different agronomic performance, designated WR02-145-1, WR01-145-2, WR02-145-3, and WR02-145-4, were produced from a cross between 2D nullisomic wheat (Triticum aestivum L. cv. "Xiaoyan 6") and rye (Secale cereale L. cv. "German White"). The chromosomal constitution of 2n=42=21 in WR02-145 lines was confirmed by cytological and molecular cytogenetic methods. Using genomic in situ hybridization on root tip chromosome preparations, a pair of intact rye chromosomes was detected in the WR02-145 lines. PCR using chromosome-specific primers confirmed the presence of 2R chromosomes of rye in these wheat-rye lines, indicating that WR02-145 lines are disomic chromosome substitution lines 2R (2D). The WR02-145 lines are resistant to the powdery mildew (Erysiphe graminis DC. f. sp. tritici E. Marchal) isolates prevalent in northern China and may possess gene(s) for resistance to powdery mildew, which differ from the previously identified Pm7 gene located on chromosome 2RL. The newly developed "Xiaoyan 6"- "German White"2R (2D) chromosome substitution lines are genetically stable, show desirable agronomic traits, and are expected to be useful in wheat improvement.

  9. A new chromosome nomenclature system for oat (Avena sativa L. and A. byzantina C. Koch) based on FISH analysis of monosomic lines.

    Science.gov (United States)

    Sanz, M J; Jellen, E N; Loarce, Y; Irigoyen, M L; Ferrer, E; Fominaya, A

    2010-11-01

    Fluorescent in situ hybridization (FISH) with multiple probes was used to analyze mitotic and meiotic chromosome spreads of Avena sativa cv 'Sun II' monosomic lines, and of A. byzantina cv 'Kanota' monosomic lines from spontaneous haploids. The probes used were A. strigosa pAs120a (a repetitive sequence abundant in A-genome chromatin), A. murphyi pAm1 (a repetitive sequence abundant in C-genome chromatin), A. strigosa pITS (internal transcribed spacer of rDNA) and the wheat rDNA probes pTa71 (nucleolus organizer region or NOR) and pTa794 (5S). Simultaneous and sequential FISH employing pairs of these probes allowed the identification and genome assignation of all chromosomes. FISH mapping using mitotic and meiotic metaphases facilitated the genomic and chromosomal identification of the monosome in each line. Of the 17 'Sun II' lines analyzed, 13 distinct monosomic lines were found, corresponding to four monosomes of the A-genome, five of the C-genome and four of the D-genome. In addition, 12 distinct monosomic lines were detected among the 20 'Kanota' lines examined, corresponding to six monosomes of the A-genome, three of the C-genome and three of the D-genome. The results show that 19 chromosomes out of 21 of the complement are represented by monosomes between the two genetic backgrounds. The identity of the remaining chromosomes can be deduced either from one intergenomic translocation detected on both 'Sun II' and 'Kanota' lines, or from the single reciprocal, intergenomic translocation detected among the 'Sun II' lines. These results permit a new system to be proposed for numbering the 21 chromosome pairs of the hexaploid oat complement. Accordingly, the A-genome contains chromosomes 8A, 11A, 13A, 15A, 16A, 17A and 19A; the C-genome contains chromosomes 1C, 2C, 3C, 4C, 5C, 6C and 7C; and the D-genome consists of chromosomes 9D, 10D, 12D, 14D, 18D, 20D and 21D. Moreover, the FISH patterns of 16 chromosomes in 'Sun II' and 15 in 'Kanota' suggest that these

  10. Transmission and recombination of homeologous Solanum sitiens chromosomes in tomato.

    Science.gov (United States)

    Pertuzé, Ricardo A; Ji, Yuanfu; Chetelat, Roger T

    2003-11-01

    The goal of the present experiments was to transfer the chromosomes of Solanum sitiens (syn. Solanum rickii) into cultivated tomato ( Lycopersicon esculentum). By crossing an allotetraploid L. esculentum x Solanum sitiens hybrid to sesquidiploid L. esculentum x S. lycopersicoides, a trigenomic hybrid (2n+14=38) was obtained. Analysis of the latter by GISH (genomic in situ hybridization) indicated it contained a full set of 12 S. sitiens chromosomes, plus two extras from S. lycopersicoides. This and other complex hybrids were pollinated with Lycopersicon pennellii-derived bridging lines to overcome unilateral incompatibility. A total of 40 progeny were recovered by embryo rescue, including diploids and aneuploids (up to 2n+8). In order to determine the origin of chromosomes and the location of introgressed segments, progeny were genotyped with RFLP markers. S. sitiens-specific markers on all chromosomes, except 6 and 11, were detected in the progeny. Several S. sitiens chromosomes were transmitted intact, either through chromosome addition (i.e., trisomics) or substitution (i.e., disomics). Recombination between S. sitiens and L. esculentum was detected on most chromosomes, in both diploid and aneuploid progeny. A monosomic alien addition line for S. sitiens chromosome 8 was identified, and the extra chromosome was stably transmitted to approximately 13% of the backcross progeny. This study demonstrates the feasibility of gene transfer from S. sitiens to L. esculentum through chromosome addition, substitution, and recombination in the progeny of complex aneuploid hybrids.

  11. Identification of Multiple Alleles at the Wx Locus and Development of Single Segment Substitution Lines for the Alleles in Rice

    Institute of Scientific and Technical Information of China (English)

    ZENG Rui-zhen; ZHANG Ze-min; HE Feng-hua; XI Zhang-ying; Akshay TALUKDAR; SHI Jun-qiong; QIN Li-jun; HUANG Chao-feng; ZHANG Gui-quan

    2006-01-01

    The microsatellite markers 484/485 and 484/W2R were used to identify the multiple alleles at the Wx locus in rice germplasm. Fifteen alleles were identified in 278 accessions by using microsatellite class and G-T polymorphism. Among these alleles, (CT)12-G, (CT)15-G, (CT)16-G, (CT)17-G, (CT)18-G and (CT)21-G have not been reported. Seventy-two single-segment substitution lines (SSSLs) carrying different alleles at the Wx locus were developed by using Huajingxian 74 with the (CT)11-G allele as a recipient and 20 accessions containing 12 different alleles at the Wx locus as donors. The estimated length of the substituted segments ranged from 2.2 to 77.3 cM with an average of 17.4 cM.

  12. 野生黄瓜代换系的构建%Construction of Wild Cucumber Substitution Lines

    Institute of Scientific and Technical Information of China (English)

    李学峰; 胡晓文; 张圣平; 顾兴芳; 张忠华; 黄三文

    2011-01-01

    Cucumis sativus var. hardwickii Royle is the only extant wild subspecies of domesticated cucumber ( Cucumis sativus var. sativus L. ). The wild cucumber contains several favorable traits including root-knot nematodes and CMV resistance, etc. It has a strong branching capability. The fruit shape of wild cucumber is oval and it tastes very bitter. In this study, we created a set of substitution lines using wild cucumber accession lines PI183967 as the donor and domesticated cucumber inbred Xintaimici as the receptor. During the process of backcrossing and self crossing, the wild cucumber genomic fragments were tracked using 62 SSR markers distributed in the cucumber genome. Subsequently, 21 single-segment substitution lines and 10 double-segment substitution lines were obtained, which in total cover 96.81% of the wild cucumber genome. These substitution lines provided a new resource for the utilization of genes from wild cucumber and also the materials basis for the precise genetic analysis of quantitative traits in cucumber, as well as for the investigation of molecular mechanism of evolution from wild cucumber to domesticated cucumber.%野牛黄瓜(Cucumis sativus var.hardwickii Royle)是目前唯一被发现的黄瓜野生变种,具有抗根结线虫和CMV等优异性状,分枝性强,果实为卵圆形,味极苦.利用野生黄瓜品系PI183967为供体材料,栽培黄瓜(Cucumis sativus var.sativus L.)‘新泰密刺'纯系为受体材料,经过3次回交和1次自交,创造了一套代换系材料.在回交和自交过程中,利用均匀分布在全基凶组上的62个SSR标记,跟踪野生黄瓜的基因组片段,共选择出21份单片段和10份双片段代换系材料,共得到代换片段41个.这些野生代换片段重叠累加覆盖野生黄瓜染色体组96.81%.这套代换系材料为利用野生黄瓜的优异基因提供了新的种质资源,也为精确分析黄瓜数量性状奠定了材料基础.

  13. Construction of a Bacterial Artificial Chromosome Library of TM-1, a Standard Line for Genetics and Genomics in Upland Cotton

    Institute of Scientific and Technical Information of China (English)

    Yan Hu; Wang-Zhen Guo; Tian-Zhen Zhang

    2009-01-01

    A bacterial artificial chromosome (BAC) library was constructed for Gossyplum hirsutum acc. TM-1, a genetic and genomic standard line for Upland cotton. The library consists of 147 456 clones with an average insert size of 122.8 kb ranging from 97 to 240 kb. About 96.0% of the clones have inserts over 100 kb. Therefore, this library represents theoretically 7.4 haploid genome equivalents based on an AD genome size of 2 425 Mb. Clones were stored in 384 384- well plates and arrayed into multiplex pools for rapid and reliable library screening. BAC screening was carded out by four-round polymerase chain reactions using 23 simple sequence repeats (SSR) markers, three sequence-related amplified polymorphism markers and one pair of pdmere for a gene associated with fiber development to test the quality of the library. Correspondingly, in total 92 positive BAC clones were Identified with an average four positive clones per SSR marker, ranging from one to eight hits. Additionally, since these SSR markers have been localized to chromosome 12 (A12) and 26 (D12) according to the genetic map, these BAC clonee are expected to serve as seeds for the physical mapping of these two homologous chromosomes, sequentially map-based cloning of quantitative trait loci or genes associated with Important agronomic traits.

  14. Brassica juncea Lines with Substituted Chimeric GFP-CENH3 Give Haploid and Aneuploid Progenies on Crossing with Other Lines

    OpenAIRE

    Watts, Anshul; Singh, Sunil K.; Bhadouria, Jyoti; Naresh, Vasupalli; Bishoyi, Ashok K.; K.A. Geetha; Chamola, Rohit; Pattanayak, Debasis; Bhat, Shripad R.

    2017-01-01

    Haploids and doubled haploids are invaluable for basic genetic studies and in crop improvement. A novel method of haploid induction through genetic engineering of the Centromere Histone Protein gene, CENH3, has been demonstrated in Arabidopsis. The present study was undertaken to develop haploid inducer (HI) lines of Brassica juncea based on the principles elaborated in Arabidopsis. B. juncea was found to carry three copies of CENH3 which generated five different transcripts, of which three t...

  15. Molecular Cytogenetic Identification of a New Wheat-Rye 6R Chromosome Disomic Addition Line with Powdery Mildew Resistance.

    Directory of Open Access Journals (Sweden)

    Diaoguo An

    Full Text Available Rye (Secale cereale L. possesses many valuable genes that can be used for improving disease resistance, yield and environment adaptation of wheat (Triticum aestivum L.. However, the documented resistance stocks derived from rye is faced severe challenge due to the variation of virulent isolates in the pathogen populations. Therefore, it is necessary to develop desirable germplasm and search for novel resistance gene sources against constantly accumulated variation of the virulent isolates. In the present study, a new wheat-rye line designated as WR49-1 was produced through distant hybridization and chromosome engineering protocols between common wheat cultivar Xiaoyan 6 and rye cultivar German White. Using sequential GISH (genomic in situ hybridization, mc-FISH (multicolor fluorescence in situ hybridization, mc-GISH (multicolor GISH and EST (expressed sequence tag-based marker analysis, WR49-1 was proved to be a new wheat-rye 6R disomic addition line. As expected, WR49-1 showed high levels of resistance to wheat powdery mildew (Blumeria graminis f. sp. tritici, Bgt pathogens prevalent in China at the adult growth stage and 19 of 23 Bgt isolates tested at the seedling stage. According to its reaction pattern to different Bgt isolates, WR49-1 may possess new resistance gene(s for powdery mildew, which differed from the documented powdery mildew gene, including Pm20 on chromosome arm 6RL of rye. Additionally, WR49-1 was cytologically stable, had improved agronomic characteristics and therefore could serve as an important bridge for wheat breeding and chromosome engineering.

  16. [Development of commercially valuable traits in hexaploid triticale lines with Aegilops introgressions as dependent on the genome composition].

    Science.gov (United States)

    Adonina, I G; Orlovskaia, O A; Tereshchenko, O Yu; Koren', L V; Khotyleva, L V; Shumnyĭ, V K; Salina, E A

    2011-04-01

    Introgressive hybridization is an efficient means to improve the genetic diversity of cultivated cereals, including triticale. To identify the triticale lines with Aegilops introgressions, genotyping was carried out with ten lines obtained by crossing hexaploid triticale with genome-substitution forms of the common wheat cultivar Avrora: Avrolata (AABBUU), Avrodes (AABBSS), and Avrotika (AABBTT). The genome composition of the triticale lines was studied by in situ hybridization, and recombination events involving Aegilops and/or common wheat chromosomes were assumed for nine out of the ten lines. Translocations involving rye chromosomes were not observed. Substitutions for rye chromosomes were detected in two lines resulting from crosses with Avrolata. Genomic in situ hybridization (GISH) with Ae. umbellulata DNA and molecular genetic analysis showed that chromosome 1R was substituted with Ae. umbellulata chromosome 1U in one of the lines and that 2R(2U) substitution took place in the other line. Fluorescence in situ hybridization (FISH) with the Spelt 1 and pSc119.2 probes revealed a translocation from Ae. speltoides to the long arm of chromosome 1B in one of the two lines resulting from crosses with Avrodes and a translocation in the long arm of chromosome 7B in the other line. In addition, the pSc119.2 probe revealed chromosome 1B rearrangements in four lines resulting from crosses with Avrolata and in a line resulting from crosses with Avrotika. The lines were tested for main productivity parameters. A negative effect on all productivity parameters was demonstrated for Ae. umbellulata chromosome 2U. The overwinter survival in all of the lines was similar to or even higher than in the original triticale cultivars. A substantial increase in winter resistance as compared with the parental cultivar was observed for the line carrying the T7BS-7SL translocation. The line with the 1R(1U) chromosome substitution seemed promising for the baking properties of triticale.

  17. The gene coding for glial cell line derived neurotrophic factor (GDNF) maps to chromosome 5p12-p13.1

    Energy Technology Data Exchange (ETDEWEB)

    Schindelhauer, D.; Schuffenhauer, S.; Meitinger, T. [Maximiland-Universitaet, Munich (Germany)] [and others

    1995-08-10

    The gene coding for glial cell line derived neurotrophic factor (GDNF) has biological properties that may have potential as a treatment for Parkinson`s and motoneuron diseases. Using the NIGMS Mapping Panel 2, we have localized the GDNF gene to human chromosome 5p12-p13.1. Large NruI and NotI fragments on chromosome 5 will facilitate the construction of a long-range map of the region. 26 refs., 1 fig., 1 tab.

  18. Error-prone ZW pairing and no evidence for meiotic sex chromosome inactivation in the chicken germ line.

    Science.gov (United States)

    Guioli, Silvana; Lovell-Badge, Robin; Turner, James M A

    2012-01-01

    In the male mouse the X and Y chromosomes pair and recombine within the small pseudoautosomal region. Genes located on the unsynapsed segments of the X and Y are transcriptionally silenced at pachytene by Meiotic Sex Chromosome Inactivation (MSCI). The degree to which MSCI is conserved in other vertebrates is currently unclear. In the female chicken the ZW bivalent is thought to undergo a transient phase of full synapsis at pachytene, starting from the homologous ends and spreading through the heterologous regions. It has been proposed that the repair of the ZW DNA double-strand breaks (DSBs) is postponed until diplotene and that the ZW bivalent is subject to MSCI, which is independent of its synaptic status. Here we present a distinct model of meiotic pairing and silencing of the ZW pair during chicken oogenesis. We show that, in most oocytes, DNA DSB foci on the ZW are resolved by the end of pachytene and that the ZW desynapses in broad synchrony with the autosomes. We unexpectedly find that ZW pairing is highly error prone, with many oocytes failing to engage in ZW synapsis and crossover formation. Oocytes with unsynapsed Z and W chromosomes nevertheless progress to the diplotene stage, suggesting that a checkpoint does not operate during pachytene in the chicken germ line. Using a combination of epigenetic profiling and RNA-FISH analysis, we find no evidence for MSCI, associated with neither the asynaptic ZW, as described in mammals, nor the synaptic ZW. The lack of conservation of MSCI in the chicken reopens the debate about the evolution of MSCI and its driving forces.

  19. Comparative Study of Domoic Acid and Okadaic Acid Induced - Chromosomal Abnormalities in the CACO-2 Cell Line

    Directory of Open Access Journals (Sweden)

    Edmond E. Creppy

    2006-03-01

    Full Text Available Okadaic Acid (OA the major diarrheic shellfish poisoning (DSP toxin is known as a tumor promoter and seems likely implicated in the genesis of digestive cancer. Little is known regarding genotoxicity and carcinogenicity of Domoic Acid (DA, the major Amnesic Shellfish Poisoning (ASP toxin. Both OA and DA occur in seafood and are of human health concerns. Micronuclei (MN arise from abnormalities in nuclear division during mitosis due to a failure of the mitotic spindle or by complex chromosomal configurations that pose problems during anaphase. In order to evaluate the ability of okadaic acid (OA and domoic acid (DA to induce DNA damage we performed the micronucleus assay using the Caco-2 cell line. To discriminate between a clastogenic or aneugenic effect of OA and DA, the micronucleus assay was conducted by cytokinesis-block micronucleus assay using cytochalasin B with Giemsa staining and/or acridine orange staining, in parallel to fluorescence in situ hybridization (FISH using a concentrated human pan-centromeric chromosome paint probe. Our results showed that OA and DA significantly increased the frequency of MN in Caco-2 cells. The MN caused by OA are found in mononucleated cells and binucleated cells, whereas those caused by DA are mainly in binucleated cells. The results of FISH analysis showed that OA induced centromere-positive micronuclei and DA increased the percentage of MN without a centromeric signal. In conclusion, both OA and DA bear mutagenic potential as revealed in Caco-2 cells by induction of MN formation. Moreover, OA induced whole chromosome loss suggesting a specific aneugenic potential, whereas DA seems simply clastogenic. At present, one cannot rule out possible DNA damage of intestinal cells if concentrations studied are reached in vivo, since this may happen with concentrations of toxins just below regulatory limits in case of frequent consumption of contaminated shell fishes.

  20. Error-prone ZW pairing and no evidence for meiotic sex chromosome inactivation in the chicken germ line.

    Directory of Open Access Journals (Sweden)

    Silvana Guioli

    Full Text Available In the male mouse the X and Y chromosomes pair and recombine within the small pseudoautosomal region. Genes located on the unsynapsed segments of the X and Y are transcriptionally silenced at pachytene by Meiotic Sex Chromosome Inactivation (MSCI. The degree to which MSCI is conserved in other vertebrates is currently unclear. In the female chicken the ZW bivalent is thought to undergo a transient phase of full synapsis at pachytene, starting from the homologous ends and spreading through the heterologous regions. It has been proposed that the repair of the ZW DNA double-strand breaks (DSBs is postponed until diplotene and that the ZW bivalent is subject to MSCI, which is independent of its synaptic status. Here we present a distinct model of meiotic pairing and silencing of the ZW pair during chicken oogenesis. We show that, in most oocytes, DNA DSB foci on the ZW are resolved by the end of pachytene and that the ZW desynapses in broad synchrony with the autosomes. We unexpectedly find that ZW pairing is highly error prone, with many oocytes failing to engage in ZW synapsis and crossover formation. Oocytes with unsynapsed Z and W chromosomes nevertheless progress to the diplotene stage, suggesting that a checkpoint does not operate during pachytene in the chicken germ line. Using a combination of epigenetic profiling and RNA-FISH analysis, we find no evidence for MSCI, associated with neither the asynaptic ZW, as described in mammals, nor the synaptic ZW. The lack of conservation of MSCI in the chicken reopens the debate about the evolution of MSCI and its driving forces.

  1. De novo LINE-1 retrotransposition in HepG2 cells preferentially targets gene poor regions of chromosome 13.

    Science.gov (United States)

    Bojang, Pasano; Anderton, Mark J; Roberts, Ruth A; Ramos, Kenneth S

    2014-08-01

    Long interspersed nuclear elements (Line-1 or L1s) account for ~17% of the human genome. While the majority of human L1s are inactive, ~80-100 elements remain retrotransposition competent and mobilize through RNA intermediates to different locations within the genome. De novo insertions of L1s account for polymorphic variation of the human genome and disruption of target loci at their new location. In the present study, fluorescence in situ hybridization and DNA sequencing were used to characterize retrotransposition profiles of L1(RP) in cultured human HepG2 cells. While expression of synthetic L1(RP) was associated with full-length and truncated insertions throughout the entire genome, a strong preference for gene-poor regions, such as those found in chromosome 13 was observed for full-length insertions. These findings shed light into L1 targeting mechanisms within the human genome and question the putative randomness of L1 retrotransposition.

  2. 3. Chromosomal instability in B-lymphoblasotoid cell lines from Werner's and Bloom's syndrome patients

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@Werner's syndrome (WS) and Bloom's syndrome (BS) are rare autosomal recessive diseases in which the feature of premature aging and the elevated risk of neoplasia may be associated with genomic instability. To cha-racterize the genomic instability of WS and BS, B-lymphoblastoid cell lines (LCLs) from WS and BS patients were cytogenetically analyzed, comparing to those from healthy donors. Although all

  3. Chromosome Substitution Lines in Cotton Improvement%用于棉花改良的染色体置换系

    Institute of Scientific and Technical Information of China (English)

    Sukumar SAHA; Dwaine A. RASKA; Osman A. GUTIéRREZ; Johnie N. JENKINS; Jack C. McCARTY, Jr.; Roy G. CANTRELL; Richard G. PERCY; David M. STELLY

    2002-01-01

    @@ Presently cotton breeders are confronting serious challenges due to the extensive use of narrow genetic base in Upland cotton, Gossypium hirsutum. Unique germplasm that incorporates new alleles must be developed to provide improved genetic potential for yield, pest and disease resistance.

  4. Phenotype transformation of immortalized NCM460 colon epithelial cell line by TGF-β1 is associated with chromosome instability.

    Science.gov (United States)

    Huang, Chao; Wen, Bin

    2016-10-01

    Transforming growth factor-β1 (TGF-β1) within tumor microenvironment has a pivotal function in cancer initiation and tumorigenesis, and hence this study was to observe the malignant transformation induced by TGF-β1 in an immortalized colon epithelial cell line NCM460 for better understanding the mechanisms of colon carcinogenesis. Immortalized colon epithelial cell line NCM460 was used as the model of this study, and was treated with different concentrations of TGF-β1 for different time. Then, immunofluorescence was performed to observe the change of phenotype hallmarks including adherent junction protein E-cadherin, cytoskeleton protein vimentin, and tight junction marker ZO-1, western blotting analysis was performed to detect the expression of the above three markers and two transcription factors (Snail and Slug) involved in the transformation by TGF-β1. In addition, chromosome instability (CHI) including analysis of DNA-ploid was detected by flow cytometry. Our results revealed significant loss or reduction of ZO-1 and E-cadherin, and robust emergence of vimentin in the cell line NCM460 after a 15-, 20-, and 25-day treatment with 10 ng/ml TGF-β1. Interestingly, 20 and 25 days after stimulation with 5 ng/ml TGF-β1, expression of E-cadherin and ZO-1 revealed a pattern roughly similar to that of 10 ng/ml TGF-β1, especially, both expressions was vanished and vimentin expression was dramatically increased at days 25 after TGF-β1 stimulation. After a stimulation with 10 ng/ml TGF-β1 for 15, 20, and 25 days, the levels of Snail and Slug expression in the cells were significantly up-regulated, compared with the cells treated with TGF-β1 inhibitor LY364947, PBS or balnk control (P TGF-β1 after its stimulation for 15, 20, and 25 days. Very few mitotic cells with treatment of PBS for 15, 20 and 25 days were non-diploid whose DNA content was greater or less than 4 N, but these cells were significantly increased after exposure to TGF-β1 for 15, 20, and

  5. A new human natural killer leukemia cell line, IMC-1. A complex chromosomal rearrangement defined by spectral karyotyping: functional and cytogenetic characterization.

    Science.gov (United States)

    Chen, I-Ming; Whalen, Margaret; Bankhurst, Arthur; Sever, Cordelia E; Doshi, Rashmi; Hardekopf, David; Montgomery, Karen; Willman, Cheryl L

    2004-03-01

    A new human IL-2 dependent leukemic cell line with a natural killer (NK) cell phenotype, IMC-1, was established from an adult patient with aggressive NK cell leukemia. The IMC-1 cell line expresses the CD56, CD2, CD11a, CD38 and HLA-DR cell surface antigens, whereas the CD16 and CD8 antigens expressed on the primary leukemic blasts from which the cell line was derived were lost after 7 and 28 weeks of culture, respectively. The IMC-1 cell line displays functional NK cytotoxicity and lyses target cells in a non-MHC restricted, antibody-independent manner with equal or superior efficiency to freshly isolated NK cells. Cytogenetic analysis at presentation and after 55 weeks in culture revealed complex structural and numerical abnormalities, defined by classic G-banding and by spectral karyotyping (SKY). Three apparently intact copies of chromosome 8 occurred in the diagnostic bone marrow specimen; the cell line also contains three copies of chromosome 8 but each was structurally altered. The development and detailed characterization of this new NK leukemic cell line will facilitate biologic and functional studies of NK cells and chromosomal aberrations potentially important in leukemic transformation.

  6. High Chromosome Number in hematological cancer cell lines is a Negative Predictor of Response to the inhibition of Aurora B and C by GSK1070916

    Directory of Open Access Journals (Sweden)

    Hardwicke Mary

    2011-07-01

    Full Text Available Abstract Background Aurora kinases play critical roles in mitosis and are being evaluated as therapeutic targets in cancer. GSK1070916 is a potent, selective, ATP competitive inhibitor of Aurora kinase B and C. Translation of predictive biomarkers to the clinic can benefit patients by identifying the tumors that are more likely to respond to therapies, especially novel inhibitors such as GSK1070916. Methods 59 Hematological cancer-derived cell lines were used as models for response where in vitro sensitivity to GSK1070916 was based on both time and degree of cell death. The response data was analyzed along with karyotype, transcriptomics and somatic mutation profiles to determine predictors of response. Results 20 cell lines were sensitive and 39 were resistant to treatment with GSK1070916. High chromosome number was more prevalent in resistant cell lines (p-value = 0.0098, Fisher Exact Test. Greater resistance was also found in cell lines harboring polyploid subpopulations (p-value = 0.00014, Unpaired t-test. A review of NOTCH1 mutations in T-ALL cell lines showed an association between NOTCH1 mutation status and chromosome number (p-value = 0.0066, Fisher Exact Test. Conclusions High chromosome number associated with resistance to the inhibition of Aurora B and C suggests cells with a mechanism to bypass the high ploidy checkpoint are resistant to GSK1070916. High chromosome number, a hallmark trait of many late stage hematological malignancies, varies in prevalence among hematological malignancy subtypes. The high frequency and relative ease of measurement make high chromosome number a viable negative predictive marker for GSK1070916.

  7. MYC, TP53, and Chromosome 17 Copy-Number Alterations in Multiple Gastric Cancer Cell Lines and in Their Parental Primary Tumors

    Directory of Open Access Journals (Sweden)

    Mariana Ferreira Leal

    2011-01-01

    Full Text Available We evaluated whether MYC, TP53, and chromosome 17 copy-number alterations occur in ACP02, ACP03, and AGP01 gastric cancer cell lines and in their tumor counterpart. Fluorescence in situ hybridization for MYC and TP53 genes and for chromosome 17 was applied in the 6th, 12th, 60th, and 85th passages of the cell lines and in their parental primary tumors. We observed that three and four MYC signals were the most common alterations in gastric cell lines and tumors. ACP02 presented cells with two copies of chr17 and loss of one copy of TP53 more frequently than ACP03 and AGP01. Only ACP03 and AGP01 presented clonal chr17 trisomy with three or two TP53 copies. The frequency of MYC gain, TP53 loss, and chromosome 17 trisomy seems to increase in gastric cell lines compared to their parental tumors. Our findings reveal that these cell lines retain, in vitro, the genetic alterations presented in their parental primary tumors.

  8. Transposon-mediated chromosomal integration of transgenes in the parasitic nematode Strongyloides ratti and establishment of stable transgenic lines.

    Directory of Open Access Journals (Sweden)

    Hongguang Shao

    Full Text Available Genetic transformation is a potential tool for analyzing gene function and thereby identifying new drug and vaccine targets in parasitic nematodes, which adversely affect more than one billion people. We have previously developed a robust system for transgenesis in Strongyloides spp. using gonadal microinjection for gene transfer. In this system, transgenes are expressed in promoter-regulated fashion in the F1 but are silenced in subsequent generations, presumably because of their location in repetitive episomal arrays. To counteract this silencing, we explored transposon-mediated chromosomal integration of transgenes in S. ratti. To this end, we constructed a donor vector encoding green fluorescent protein (GFP under the control of the Ss-act-2 promoter with flanking inverted tandem repeats specific for the piggyBac transposon. In three experiments, free-living Strongyloides ratti females were transformed with this donor vector and a helper plasmid encoding the piggyBac transposase. A mean of 7.9% of F1 larvae were GFP-positive. We inoculated rats with GFP-positive F1 infective larvae, and 0.5% of 6014 F2 individuals resulting from this host passage were GFP-positive. We cultured GFP-positive F2 individuals to produce GFP-positive F3 L3i for additional rounds of host and culture passage. Mean GFP expression frequencies in subsequent generations were 15.6% in the F3, 99.0% in the F4, 82.4% in the F5 and 98.7% in the F6. The resulting transgenic lines now have virtually uniform GFP expression among all progeny after at least 10 generations of passage. Chromosomal integration of the reporter transgenes was confirmed by Southern blotting and splinkerette PCR, which revealed the transgene flanked by S. ratti genomic sequences corresponding to five discrete integration sites. BLAST searches of flanking sequences against the S. ratti genome revealed integrations in five contigs. This result provides the basis for two powerful functional genomic tools

  9. Chromosomal imbalance maps of human 5FU-resistant colorectal cancer cell lines: implications in the analysis of 5FU-acquired resistance mechanisms.

    Science.gov (United States)

    Plasencia, C; Rooney, P H; Taron, M; Martinez-Balibrea, E; McLeod, H L; Abad, A

    2003-05-01

    Thymidylate synthase (TS), a critical enzyme in the de novo synthesis of thymidylate, is an important target for fluoropyrimidines and folate-based TS inhibitors. Overexpression of TS has been correlated to 5-fluorouracil (5FU)-resistance. Because 5FU still remains a basic component of the treatment of colorectal cancer, circumvention of resistance is of vital importance. A panel of sensitive (HT29 and LoVo) and 5FU-resistant colorectal cancer cell lines (HT29-5FUR and LoVo-5FUR) were subjected to comparative genomic hybridization (CGH) analysis to identify possible amplified/deleted regions associated with 5FU-resistance in colon tumours. We have identified chromosomal gains at 5p, 6, 7p, 7q and 8q and one loss at 3q in 5FU-resistant cells as compared to corresponding sensitive cell lines. Neither chromosomal gains at 18p nor gene amplification of TS were observed in our resistant cell lines although an overexpression of TS gene exists (at mRNA level) in these cell lines as compared with corresponding parental cells. Most of the chromosomal gains identified in this study occur frequently in sporadic colorectal tumours and has been associated to a poor prognosis and a greater progression of the tumour and could be related to a worse chemotherapy response. The chromosomal imbalance profile detected in 5FU-resistant cell lines should provide a basis for interpreting mechanisms of 5FU-resistance in colorectal cancer and also possibly in other tumours treated with this agent. This study also identified new genes potentially implicated in 5FU-resistance and suggests new targets that could be useful for the chemotherapy treatment of colorectal cancer.

  10. Association of a single nucleotide polymorphic variation in the human chromosome 19q13.3 with drug responses in the NCI60 cell lines

    DEFF Research Database (Denmark)

    Nissen, K.K.; Vogel, Ulla Birgitte; Nexo, B.A.

    2009-01-01

    We studied the importance of certain polymorphisms on human chromosome 19q13.3 for drug sensitivity in human tumor cell cultures. NCI60 is a panel of 60 established tumor-derived cell lines, which have been tested for their sensitivity to tens of thousands of different drugs. Here we investigate...... the correlations between the responses of the NCI60 cells to different anticancer drugs and their respective alleles of five DNA polymorphisms located in a cancer-related chromosomal area. One polymorphism, located in the 5' noncoding region of the gene ASE-1, alias CD3EAP, proved to be associated with drug...... sensitivity (P=0.025). The same polymorphism has previously been associated with treatment response of multiple myeloma after bone marrow ablation. The polymorphism ASE-1-e1 was of importance for the drug response in the human cancer cell lines investigated and could eventually become important...

  11. Cloning of a parathyroid hormone/parathyroid hormone-related peptide receptor (PTHR) cDNA from a rat osteosarcoma (UMR 106) cell line: Chromosomal assignment of the gene in the human, mouse, and rat genomes

    Energy Technology Data Exchange (ETDEWEB)

    Pausova, Z.; Bourdon, J.; Clayton, D.; Janicic, N.; Goltzman, D.; Hendy, G.N. (McGill Univ. and Royal Victoria Hospital, Montreal Quebec (Canada)); Mattei, M.G. (INSERM, Marseille (France)); Seldin, M.F. (Duke Univ. Medical Center, Durham, NC (United States)); Riviere, M.; Szpirer, J. (Universite Libre de Bruxelles, Rhode-St-Genese (Belgium)) (and others)

    1994-03-01

    Complementary DNAs spanning the entire coding region of the rat parathyroid hormone/parathyroid hormone-related peptide receptor (PTHR) were isolated from a rat osteosarcoma (UMR 106) cell-line cDNA library. The longest of these clones (rPTHrec4) was used to chromosomally assign the PTHR gene in the human, rat, and mouse genomes. By somatic cell hybrid analysis, the gene was localized to human chromosome 3 and rat chromosome 8; by in situ hybridization, the gene was mapped to human chromosome 3p21.1-p22 and to mouse chromosome 9 band F; and by interspecific backcross analysis, the Pthr gene segregated with the transferrin (Trf) gene in chromosome 9 band F. Mouse chromosome 9 and rat chromosome 8 are known to be highly homologous and to also show synteny conservation with human chromosome 3. These three chromosomes share the transferrin gene (TF), the myosin light polypeptide 3 gene (MYL3), and the acelpeptide hydrolase gene (APEH). These results add a fourth gene, the PTHR gene, to the synteny group conserved in these chromosomes. 34 refs., 7 figs. 1 tab.

  12. Fate of Aegilops speltoides-derived, repetitive DNA sequences in diploid Aegilops species, wheat-Aegilops amphiploids and derived chromosome addition lines.

    Science.gov (United States)

    Kumar, S; Friebe, B; Gill, B S

    2010-07-01

    The present study reports the cloning and characterization of an Aegilops speltoides-derived subtelomeric repeat, designated as pSp1B16. Clone pSp1B16 has 98% sequence homology with the previously isolated Ae. speltoides repeat Spelt1. The distribution of pSp1B16 and another Ae. speltoides repeat, pGc1R1, was analyzed in diploid Aegilops species, tetra- and hexaploid wheats, wheat-Aegilops amphiploids and derived chromosome addition lines by fluorescence in situ hybridization (FISH). Clones pSp1B16 and pGc1R1 revealed FISH sites in Ae. speltoides, Ae. sharonensis and Triticum timopheevii, whereas additional pGc1R1 FISH sites were observed in Ae. longissima and Ae. caudata. The pSp1B16 and pGc1R1 FISH patterns of the Aegilops chromosomes in the wheat-Aegilops amphiploids and chromosome addition lines are similar to those present in the Aegilops parent accession. We did not observe any evidence of pSp1B16 and pGc1R1 sequence elimination, which is in contrast to previous studies using similar hybrids and repeats. The presented data suggest that the genomic changes in synthetic amphiploids observed in previous studies might be caused by homoeologous recombination, which was suppressed in the amphiploid analyzed in this study.

  13. Alteration of Terminal Heterochromatin and Chromosome Rearrangements in Derivatives of Wheat-Rye Hybrids

    Institute of Scientific and Technical Information of China (English)

    Shulan Fu; Zhenling Lv; Xiang Guo; Xiangqi Zhang; Fangpu Han

    2013-01-01

    Wheat-rye addition and substitution lines and their self progenies revealed variations in telomeric heterochromatin and centromeres.Furthermore,a mitotically unstable dicentric chromosome and stable multicentric chromosomes were observed in the progeny of a Chinese Spring-Imperial rye 3R addition line.An unstable multicentric chromosome was found in the progeny of a 6R/6D substitution line.Drastic variation of terminal heterochromatin including movement and disappearance of terminal heterochromatin occurred in the progeny of wheatrye addition line 3R,and the 5RS ditelosomic addition line.Highly stable minichromosomes were observed in the progeny of a monosomic 4R addition line,a ditelosomic 5RS addition line and a 6R/6D substitution line.Minichromosomes,with and without the FISH signals for telomeric DNA (TTTAGGG)n,derived from a monosomic 4R addition line are stable and transmissible to the next generation.The results indicated that centromeres and terminal heterochromatin can be profoundly altered in wheat-rye hybrid derivatives.

  14. Chromosome Analysis

    Science.gov (United States)

    1998-01-01

    Perceptive Scientific Instruments, Inc., provides the foundation for the Powergene line of chromosome analysis and molecular genetic instrumentation. This product employs image processing technology from NASA's Jet Propulsion Laboratory and image enhancement techniques from Johnson Space Center. Originally developed to send pictures back to earth from space probes, digital imaging techniques have been developed and refined for use in a variety of medical applications, including diagnosis of disease.

  15. A study of aneuploidy and DNA fragmentation in spermatozoa of three men with sex chromosome mosaicism including a 45,X cell line.

    Science.gov (United States)

    Nguyen, Minh Huong; Morel, Frederic; Bujan, Louis; May-Panloup, Pascale; De Braekeleer, Marc; Perrin, Aurore

    2015-06-01

    Meiotic segregation of mosaic males with a 45,X cell line has been little examined. In this study, we evaluated the risk of aneuploid gametes using fluorescence in situ hybridization (FISH) and DNA fragmentation in ejaculated spermatozoa of three men with sex chromosome mosaicism including a 45,X cell line. Triple- and dual-color FISH were performed. Sperm DNA fragmentation was detected using the TUNEL assay. A significantly increased frequency of XY disomic spermatozoa was observed for patients (P)1 and P2. A significant increase in diploidy and autosomal aneuploidy was found in P2 and P3, respectively. The rate of DNA fragmentation was not different from that observed in a control group. Data from the literature are scarce (only 3 cases reported), making comparison of the present data difficult, especially as the frequencies of the cell lines comprising the mosaicism differed between patients. Furthermore, the proportion of the different cell lines can differ from one tissue to another in the same patient. Whether the relative levels of the several cell lines present in the mosaicism can influence the rate of aneuploid spermatozoa remains unknown.

  16. Chromosomal location and comparative genomics analysis of powdery mildew resistance gene Pm51 in a putative wheat-Thinopyrum ponticum introgression line.

    Science.gov (United States)

    Zhan, Haixian; Li, Guangrong; Zhang, Xiaojun; Li, Xin; Guo, Huijuan; Gong, Wenping; Jia, Juqing; Qiao, Linyi; Ren, Yongkang; Yang, Zujun; Chang, Zhijian

    2014-01-01

    Powdery mildew (PM) is a very destructive disease of wheat (Triticum aestivum L.). Wheat-Thinopyrum ponticum introgression line CH7086 was shown to possess powdery mildew resistance possibly originating from Th. ponticum. Genomic in situ hybridization and molecular characterization of the alien introgression failed to identify alien chromatin. To study the genetics of resistance, CH7086 was crossed with susceptible genotypes. Segregation in F2 populations and F2:3 lines tested with Chinese Bgt race E09 under controlled conditions indicated that CH7086 carries a single dominant gene for powdery mildew resistance. Fourteen SSR and EST-PCR markers linked with the locus were identified. The genetic distances between the locus and the two flanking markers were 1.5 and 3.2 cM, respectively. Based on the locations of the markers by nullisomic-tetrasomic and deletion lines of 'Chinese Spring', the resistance gene was located in deletion bin 2BL-0.89-1.00. Conserved orthologous marker analysis indicated that the genomic region flanking the resistance gene has a high level of collinearity to that of rice chromosome 4 and Brachypodium chromosome 5. Both resistance specificities and tests of allelism suggested the resistance gene in CH7086 was different from previously reported powdery mildew resistance genes on 2BL, and the gene was provisionally designated PmCH86. Molecular analysis of PmCH86 compared with other genes for resistance to Bgt in the 2BL-0.89-1.00 region suggested that PmCH86 may be a new PM resistance gene, and it was therefore designated as Pm51. The closely linked flanking markers could be useful in exploiting this putative wheat-Thinopyrum translocation line for rapid transfer of Pm51 to wheat breeding programs.

  17. Facile synthesis of novel substituted aryl-thiazole (SAT) analogs via one-pot multi-component reaction as potent cytotoxic agents against cancer cell lines.

    Science.gov (United States)

    Mirza, Salma; Asma Naqvi, Syeda; Mohammed Khan, Khalid; Salar, Uzma; Choudhary, M Iqbal

    2017-02-01

    In this study, twenty-five (25) substituted aryl thiazoles (SAT) 1-25 were synthesized, and their in vitro cytotoxicity was evaluated against four cancer cell lines, MCF-7 (ER(+ve) breast), MDA-MB-231 (ER(-ve) breast), HCT116 (colorectal) and HeLa (cervical). The activity was compared with the standard anticancer drug doxorubicin (IC50=1.56±0.05μM). Among them, compounds 1, 4-8, and 19 were found to be toxic to all four cancer cell lines (IC50 values 5.37±0.56-46.72±1.80μM). Compound 20 was selectively active against MCF7 breast cancer cells with IC50 of 40.21±4.15μM, whereas compound 19 was active against MCF7 and HeLa cells with IC50 of 46.72±1.8, and 19.86±0.11μM, respectively. These results suggest that substituted aryl thiazoles 1 and 4 deserve to be further investigated in vivo as anticancer leads.

  18. Antiproliferative and Pro-Apoptotic Effect of Novel Nitro-Substituted Hydroxynaphthanilides on Human Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Tereza Kauerova

    2016-07-01

    Full Text Available Ring-substituted hydroxynaphthanilides are considered as cyclic analogues of salicylanilides, compounds possessing a wide range of pharmacological activities, including promising anticancer properties. The aim of this study was to evaluate the potential anticancer effect of novel nitro-substituted hydroxynaphthanilides with a special focus on structure-activity relationships. The antiproliferative effect was assessed by Water Soluble Tetrazolium Salts-1 (WST-1 assay, and cytotoxicity was evaluated via dye exclusion test. Flow cytometry was used for cell cycle analysis and detection of apoptosis using Annexin V-FITC/PI assay. Protein expression was estimated by Western blotting. Our data indicate that the potential to cause the antiproliferative effect increases with the shift of the nitro substituent from the ortho- to the para-position. The most potent compounds, 3-hydroxy-N-(3-nitrophenylnaphthalene-2-carboxamide (2, and 2-hydroxy-N-(4-nitrophenyl-naphthalene-1-carboxamide (6 showed antiproliferative activity against THP-1 and MCF-7 cancer cells without affecting the proliferation of 3T3-L1 non-tumour cells. Compounds 2 and 6 induced the accumulation of THP-1 and MCF-7 cells in G1 phase associated with the downregulation of cyclin E1 protein levels, while the levels of cyclin B1 were not affected. Moreover, compound 2 was found to exert the pro-apoptotic effect on the THP-1 cells. These results suggest that hydroxynaphthanilides might represent a potential model structure for the development of novel anticancer agents.

  19. Transcriptional profiling of type 1 diabetes genes on chromosome 21 in a rat beta-cell line and human pancreatic islets

    DEFF Research Database (Denmark)

    Bergholdt, R.; Karlsen, A.E.; Hagedorn, Peter;

    2007-01-01

    We recently finemapped a type 1 diabetes (T1D)-linked region on chromosome 21, indicating that one or more T1D-linked genes exist in this region with 33 annotated genes. In the current study, we have taken a novel approach using transcriptional profiling in predicting and prioritizing the most...... likely candidate genes influencing beta-cell function in this region. Two array-based approaches were used, a rat insulinoma cell line (INS-1alphabeta) overexpressing pancreatic duodenum homeobox 1 (pdx-1) and treated with interleukin 1beta (IL-1beta) as well as human pancreatic islets stimulated...... with a mixture of cytokines. Several candidate genes with likely functional significance in T1D were identified. Genes showing differential expression in the two approaches were highly similar, supporting the role of these specific gene products in cytokine-induced beta-cell damage. These were genes involved...

  20. A novel cell line derived from pleomorphic adenoma expresses MMP2, MMP9, TIMP1, TIMP2, and shows numeric chromosomal anomalies.

    Directory of Open Access Journals (Sweden)

    Aline Semblano Carreira Falcão

    Full Text Available Pleomorphic adenoma is the most common salivary gland neoplasm, and it can be locally invasive, despite its slow growth. This study aimed to establish a novel cell line (AP-1 derived from a human pleomorphic adenoma sample to better understand local invasiveness of this tumor. AP-1 cell line was characterized by cell growth analysis, expression of epithelial and myoepithelial markers by immunofluorescence, electron microscopy, 3D cell culture assays, cytogenetic features and transcriptomic study. Expression of matrix metalloproteinases (MMPs and their tissue inhibitors (TIMPs was also analyzed by immunofluorescence and zymography. Furthermore, epithelial and myoepithelial markers, MMPs and TIMPs were studied in the tumor that originated the cell line. AP-1 cells showed neoplastic epithelial and myoepithelial markers, such as cytokeratins, vimentin, S100 protein and smooth-muscle actin. These molecules were also found in vivo, in the tumor that originated the cell line. MMPs and TIMPs were observed in vivo and in AP-1 cells. Growth curve showed that AP-1 exhibited a doubling time of 3.342 days. AP-1 cells grown inside Matrigel recapitulated tumor architecture. Different numerical and structural chromosomal anomalies were visualized in cytogenetic analysis. Transcriptomic analysis addressed expression of 7 target genes (VIM, TIMP2, MMP2, MMP9, TIMP1, ACTA2 e PLAG1. Results were compared to transcriptomic profile of non-neoplastic salivary gland cells (HSG. Only MMP9 was not expressed in both libraries, and VIM was expressed solely in AP-1 library. The major difference regarding gene expression level between AP-1 and HSG samples occurred for MMP2. This gene was 184 times more expressed in AP-1 cells. Our findings suggest that AP-1 cell line could be a useful model for further studies on pleomorphic adenoma biology.

  1. A novel cell line derived from pleomorphic adenoma expresses MMP2, MMP9, TIMP1, TIMP2, and shows numeric chromosomal anomalies.

    Science.gov (United States)

    Falcão, Aline Semblano Carreira; Kataoka, Maria Sueli da Silva; Ribeiro, Nélson Antonio Bailão; Diniz, José Antonio Picanço; Alves, Sérgio Melo; Ribeiro, André L Ribeiro; de Siqueira, Adriane Sousa; da Silva, Artur Luiz; Ramos, Rommel Thiago Jucá; Freitas, Vanessa M; Jaeger, Ruy G; Pinheiro, João J V

    2014-01-01

    Pleomorphic adenoma is the most common salivary gland neoplasm, and it can be locally invasive, despite its slow growth. This study aimed to establish a novel cell line (AP-1) derived from a human pleomorphic adenoma sample to better understand local invasiveness of this tumor. AP-1 cell line was characterized by cell growth analysis, expression of epithelial and myoepithelial markers by immunofluorescence, electron microscopy, 3D cell culture assays, cytogenetic features and transcriptomic study. Expression of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) was also analyzed by immunofluorescence and zymography. Furthermore, epithelial and myoepithelial markers, MMPs and TIMPs were studied in the tumor that originated the cell line. AP-1 cells showed neoplastic epithelial and myoepithelial markers, such as cytokeratins, vimentin, S100 protein and smooth-muscle actin. These molecules were also found in vivo, in the tumor that originated the cell line. MMPs and TIMPs were observed in vivo and in AP-1 cells. Growth curve showed that AP-1 exhibited a doubling time of 3.342 days. AP-1 cells grown inside Matrigel recapitulated tumor architecture. Different numerical and structural chromosomal anomalies were visualized in cytogenetic analysis. Transcriptomic analysis addressed expression of 7 target genes (VIM, TIMP2, MMP2, MMP9, TIMP1, ACTA2 e PLAG1). Results were compared to transcriptomic profile of non-neoplastic salivary gland cells (HSG). Only MMP9 was not expressed in both libraries, and VIM was expressed solely in AP-1 library. The major difference regarding gene expression level between AP-1 and HSG samples occurred for MMP2. This gene was 184 times more expressed in AP-1 cells. Our findings suggest that AP-1 cell line could be a useful model for further studies on pleomorphic adenoma biology.

  2. Evaluation of Gynogenic Responsiveness and Pollen Viability of Selfed Doubled Haploid Onion Lines and Chromosome Doubling via Somatic Regeneration

    Science.gov (United States)

    Although haploid induction has been practiced in onions for the last 20 years, several obstacles limit its use in plant breeding programmes. To overcome some of them, we investigated three parameters: efficiency of doubled haploid (DH) lines and their selfed progeny as sources of high responsiveness...

  3. Marker chromosomes.

    Science.gov (United States)

    Rao, Kiran Prabhaker; Belogolovkin, Victoria

    2013-04-01

    Marker chromosomes are a morphologically heterogeneous group of structurally abnormal chromosomes that pose a significant challenge in prenatal diagnosis. Phenotypes associated with marker chromosomes are highly variable and range from normal to severely abnormal. Clinical outcomes are very difficult to predict when marker chromosomes are detected prenatally. In this review, we outline the classification, etiology, cytogenetic characterization, and clinical consequences of marker chromosomes, as well as practical approaches to prenatal diagnosis and genetic counseling.

  4. Integration of Proteomics and Transcriptomics Data Sets for the Analysis of a Lymphoma B-Cell Line in the Context of the Chromosome-Centric Human Proteome Project.

    Science.gov (United States)

    Díez, Paula; Droste, Conrad; Dégano, Rosa M; González-Muñoz, María; Ibarrola, Nieves; Pérez-Andrés, Martín; Garin-Muga, Alba; Segura, Víctor; Marko-Varga, Gyorgy; LaBaer, Joshua; Orfao, Alberto; Corrales, Fernando J; De Las Rivas, Javier; Fuentes, Manuel

    2015-09-04

    A comprehensive study of the molecular active landscape of human cells can be undertaken to integrate two different but complementary perspectives: transcriptomics, and proteomics. After the genome era, proteomics has emerged as a powerful tool to simultaneously identify and characterize the compendium of thousands of different proteins active in a cell. Thus, the Chromosome-centric Human Proteome Project (C-HPP) is promoting a full characterization of the human proteome combining high-throughput proteomics with the data derived from genome-wide expression profiling of protein-coding genes. Here we present a full proteomic profiling of a human lymphoma B-cell line (Ramos) performed using a nanoUPLC-LTQ-Orbitrap Velos proteomic platform, combined to an in-depth transcriptomic profiling of the same cell type. Data are available via ProteomeXchange with identifier PXD001933. Integration of the proteomic and transcriptomic data sets revealed a 94% overlap in the proteins identified by both -omics approaches. Moreover, functional enrichment analysis of the proteomic profiles showed an enrichment of several functions directly related to the biological and morphological characteristics of B-cells. In turn, about 30% of all protein-coding genes present in the whole human genome were identified as being expressed by the Ramos cells (stable average of 30% genes along all the chromosomes), revealing the size of the protein expression-set present in one specific human cell type. Additionally, the identification of missing proteins in our data sets has been reported, highlighting the power of the approach. Also, a comparison between neXtProt and UniProt database searches has been performed. In summary, our transcriptomic and proteomic experimental profiling provided a high coverage report of the expressed proteome from a human lymphoma B-cell type with a clear insight into the biological processes that characterized these cells. In this way, we demonstrated the usefulness of

  5. Further Report on Carcinogenesis or Tumorigenicity of MDCK Canine Kidney Cell(CKC) Lines and Analysis of Their Chromosome Karyotypes

    Institute of Scientific and Technical Information of China (English)

    ZHANG De-li; FANG Fu-de; XIA Geng-tian; HE Xu-yu; GAO Bu-xian; BAI Xiao-hong; LI Liu-jin; HUANG Gao-sheng; LIU Shang-gao; YEN Lung-fei

    2002-01-01

    Using Hela cell cultures as positive control and primary canine kidney cell (CKC) or feline kidney cell (FKC) cultures purified in vitro on passage 3 as negative control, the tumorigenicity of Madin-Darby canine kidney (MDCK) cells was tested in >273 nude mice, and colony formation in soft agarose and haemagglutination under different concentration of plant lectins of these cells were carried out at the same time. Subsequently, very low tumorigenicity strains of MDCK line were successfully selected; these were evaluated for the production of canine or feline combination viral vaccines, free of infectious agents, and of known cytogenetic and tumorigenic. It is thus evident that MDCK cell of M, JB, JC, WB or H strain can be approved as substrate for the preparation of attenuated viral vaccines, but MDCK cell of YA, YB and KA strains can not be approved as substrate for the preparation of attenuated viral vaccines. The heritable character of these cell sub-lines is comparatively stable, and shows little significant difference between passages.

  6. Cloning of a novel phosphateserine aminotransferase gene from a Triticum aestivum-Elytrigia elongatum alien substitution line with resistance to powdery mildew

    Institute of Scientific and Technical Information of China (English)

    HE Daoyi; WANG Honggang

    2005-01-01

    Shannong 551, a T. aestivum-E. elongatum alien substitution line with resistance to powdery mildew, was inoculated with pathogenic spores of powdery mildew. The leaf samples were prepared 48 h after inoculation for scanning electron microscopy. The result showed that germination of spores and growth of young mycelia on leaves of Shannong 551 were suppressed at the early stage of infection. At the same time, RNAs were prepared from the leaves for the cloning of WRP1 and RPW2 by cDNA RDA and RACE technology. BLAST analysis of the sequences indicated that both WRP1 and RPW2 were novel genes. WRP1 contains no complete ORF. RPW2 contains the conserved structure domain of aminotransferase, and its DNA sequence shares high homology with genes of phosphateserine aminotransferase in many organisms. Therefore, it is speculated as a novel phosphateserine aminotransferase gene. The results of Northern blot suggested that expression of RPW2 occurred at the early stage of infection by powdery mildew. Southern blot using the probe of RPW2, in which there was strong hybridizing signals in both genome of Shannong 551 and E. elongatum, but not in those of Jinan 13 and Lumai No.5, indicated that RPW2 derived from the genome of E. elongatum.

  7. Using chromosome introgression lines to map quantitative trait loci for photosynthesis parameters in rice (Oryza sativa L.) leaves under drought and well-watered field conditions.

    Science.gov (United States)

    Gu, Junfei; Yin, Xinyou; Struik, Paul C; Stomph, Tjeerd Jan; Wang, Huaqi

    2012-01-01

    Photosynthesis is fundamental to biomass production, but sensitive to drought. To understand the genetics of leaf photosynthesis, especially under drought, upland rice cv. Haogelao, lowland rice cv. Shennong265, and 94 of their introgression lines (ILs) were studied at flowering and grain filling under drought and well-watered field conditions. Gas exchange and chlorophyll fluorescence measurements were conducted to evaluate eight photosynthetic traits. Since these traits are very sensitive to fluctuations in microclimate during measurements under field conditions, observations were adjusted for microclimatic differences through both a statistical covariant model and a physiological approach. Both approaches identified leaf-to-air vapour pressure difference as the variable influencing the traits most. Using the simple sequence repeat (SSR) linkage map for the IL population, 1-3 quantitative trait loci (QTLs) were detected per trait-stage-treatment combination, which explained between 7.0% and 30.4% of the phenotypic variance of each trait. The clustered QTLs near marker RM410 (the interval from 57.3 cM to 68.4 cM on chromosome 9) were consistent over both development stages and both drought and well-watered conditions. This QTL consistency was verified by a greenhouse experiment under a controlled environment. The alleles from the upland rice at this interval had positive effects on net photosynthetic rate, stomatal conductance, transpiration rate, quantum yield of photosystem II (PSII), and the maximum efficiency of light-adapted open PSII. However, the allele of another main QTL from upland rice was associated with increased drought sensitivity of photosynthesis. These results could potentially be used in breeding programmes through marker-assisted selection to improve drought tolerance and photosynthesis simultaneously.

  8. Induction of small-segment-translocation between wheat and rye chromosomes

    Institute of Scientific and Technical Information of China (English)

    任正隆; 张怀琼

    1997-01-01

    A new approach to produce wheat-rye translocation, based on the genetic instability caused by monosomic addition of rye chromosome in wheat, is described. 1 283 plants from the selfed progenies of monosomic addition lines with single chromosome of inbred rye line R12 and complete chromosome complement of wheat cultivar Mianyang 11 were cytologically analyzed on a plant-by-plant basis by the improved C-banding technique. 63 of the plants, with 2n = 42, were found containing wheat-rye translocation or substitution, with a frequency of 4. 91% . Compared with the wheat parent, other 32 plants with 2n = 42 exhibited obvious phenotypic variation, but their com-ponent of rye chromosome could not be detected using the C-banding technique. In situ hybridization with a biotin-la-beled DNA probe was used to detect rye chromatin and to determine the insertion sites of rye segments in the wheat chromosomes. In 20 out of the 32 variant wheat plants, small segments of rye chromosomes were found being inserted into dif

  9. Modeling Chromosomes

    Science.gov (United States)

    Robertson, Carol

    2016-01-01

    Learning about chromosomes is standard fare in biology classrooms today. However, students may find it difficult to understand the relationships among the "genome", "chromosomes", "genes", a "gene locus", and "alleles". In the simple activity described in this article, which follows the 5E approach…

  10. The use of the ph1b mutant to induce recombination between the chromosomes of wheat and barley

    Science.gov (United States)

    Rey, María-Dolores; Calderón, María C.; Prieto, Pilar

    2015-01-01

    Intensive breeding has led to a narrowing in the genetic base of our major crops. In wheat, access to the extensive gene pool residing in its many and varied relatives (some cultivated, others wild) is hampered by the block on recombination imposed by the Ph1 (Pairing homoeologous 1) gene. Here, the ph1b mutant has been exploited to induced allosyndesis between wheat chromosomes and those of both Hordeum vulgare (cultivated barley) and H. chilense (a wild barley). A number of single chromosome Hordeum sp. substitution and addition lines in wheat were crossed and backcrossed to the ph1b mutant to produce plants in which pairing between the wheat and the non-wheat chromosomes was not suppressed by the presence of Ph1. Genomic in situ hybridization was applied to almost 500 BC1F2 progeny as a screen for allosyndetic recombinants. Chromosome rearrangements were detected affecting H. chilense chromosomes 4Hch, 5Hch, 6Hch, and 7Hch and H. vulgare chromosomes 4Hv, 6Hv, and 7Hv. Two of these were clearly the product of a recombination event involving chromosome 4Hch and a wheat chromosome. PMID:25852713

  11. Chromosome therapy. Correction of large chromosomal aberrations by inducing ring chromosomes in induced pluripotent stem cells (iPSCs).

    Science.gov (United States)

    Kim, Taehyun; Bershteyn, Marina; Wynshaw-Boris, Anthony

    2014-01-01

    The fusion of the short (p) and long (q) arms of a chromosome is referred to as a "ring chromosome." Ring chromosome disorders occur in approximately 1 in 50,000-100,000 patients. Ring chromosomes can result in birth defects, mental disabilities, and growth retardation if additional genes are deleted during the formation of the ring. Due to the severity of these large-scale aberrations affecting multiple contiguous genes, no possible therapeutic strategies for ring chromosome disorders have so far been proposed. Our recent study (Bershteyn et al.) using patient-derived fibroblast lines containing ring chromosomes, found that cellular reprogramming of these fibroblasts into induced pluripotent stem cells (iPSCs) resulted in the cell-autonomous correction of the ring chromosomal aberration via compensatory uniparental disomy (UPD). These observations have important implications for studying the mechanism of chromosomal number control and may lead to the development of effective therapies for other, more common, chromosomal aberrations.

  12. Sub-megabase resolution tiling (SMRT array-based comparative genomic hybridization profiling reveals novel gains and losses of chromosomal regions in Hodgkin Lymphoma and Anaplastic Large Cell Lymphoma cell lines

    Directory of Open Access Journals (Sweden)

    Lam Wan L

    2008-01-01

    Full Text Available Abstract Background Hodgkin lymphoma (HL and Anaplastic Large Cell Lymphoma (ALCL, are forms of malignant lymphoma defined by unique morphologic, immunophenotypic, genotypic, and clinical characteristics, but both overexpress CD30. We used sub-megabase resolution tiling (SMRT array-based comparative genomic hybridization to screen HL-derived cell lines (KMH2 and L428 and ALCL cell lines (DEL and SR-786 in order to identify disease-associated gene copy number gains and losses. Results Significant copy number gains and losses were observed on several chromosomes in all four cell lines. Assessment of copy number alterations with 26,819 DNA segments identified an average of 20 genetic alterations. Of the recurrent minimally altered regions identified, 11 (55% were within previously published regions of chromosomal alterations in HL and ALCL cell lines while 9 (45% were novel alterations not previously reported. HL cell lines L428 and KMH2 shared gains in chromosome cytobands 2q23.1-q24.2, 7q32.2-q36.3, 9p21.3-p13.3, 12q13.13-q14.1, and losses in 13q12.13-q12.3, and 18q21.32-q23. ALCL cell lines SR-786 and DEL, showed gains in cytobands 5p15.32-p14.3, 20p12.3-q13.11, and 20q13.2-q13.32. Both pairs of HL and ALCL cell lines showed losses in 18q21.32-18q23. Conclusion This study is considered to be the first one describing HL and ALCL cell line genomes at sub-megabase resolution. This high-resolution analysis allowed us to propose novel candidate target genes that could potentially contribute to the pathogenesis of HL and ALCL. FISH was used to confirm the amplification of all three isoforms of the trypsin gene (PRSS1/PRSS2/PRSS3 in KMH2 and L428 (HL and DEL (ALCL cell lines. These are novel findings that have not been previously reported in the lymphoma literature, and opens up an entirely new area of research that has not been previously associated with lymphoma biology. The findings raise interesting possibilities about the role of signaling

  13. Substitutional analysis

    CERN Document Server

    Rutherford, Daniel Edwin

    2013-01-01

    Classic monograph, suitable for advanced undergraduates and graduate students. Topics include calculus of permutations and tableaux, semi-normal representation, orthogonal and natural representations, group characters, and substitutional equations. 1968 edition.

  14. Structural Changes of 2V Chromosome of Haynaldia villosa Induced by Gametocidal Chromosome 3C of Aegilops triuncialis

    Institute of Scientific and Technical Information of China (English)

    CHEN Quan-zhan; CAO Ai-zhong; QI Zeng-jun; ZHANG Wei; CHEN Pei-du

    2008-01-01

    Haynaldia villosa (2n =2X = 14, VV), a relative of wheat, plays important roles in wheat improvement mainly owing to its disease resistance. Powdery mildew resistance gene Pm21 has been successfully transferred into wheat by Cytogenetie Institute, Nanjing Agricultural University, China, and is widely used in the current wheat breeding programs. In this research, our objective is to further transfer and utilize the beneficial genes such as eye-spot resistance, yellow rust resistance, and gene of the tufted bristles on the glume ridge (a remarkable morphology) mapped on 2V of Haynaldia villosa. A disomic addition line with gametocidal chromosome 3C ofAegilops triuncialis added in Norin-26 was crossed to the wheat-H, villosa disomic substitution 2V(2D) and the hybrid F1 was then self-crossed. Chromosome C-banding, genomie in situ hybridization (GISH), and meiotic analysis in combination with molecular markers were applied to detect the chromosome variations derived from hybrids F2 and F3. To date, four translocations including one small segmental translocation T6BS.6BL-2VS, two whole arm translocations (preliminarily designed as T3DS·2VL and T2VS·7DL) and one intercalary translocation T2VS·2VL-W-2VL, one deletion Del. 2VS·2VL-, one monotelosomic Mt2VS, and one iso- chromosome 2VS·2VS line have been developed and characterized. One wheat SSR marker Xwmc25-120 tagging 2VS and one wheat STS marker NAU/STSBCD135-1 (2BL) tagging 2VL were successfully used to confirm the alien chromosome segments involved in the seven lines. The tufted bristles on the glume ridge appeared in lines T2VS·7DL, Mt2VS, 2VS·2VS as well as the parent DS2V(2D), whereas in T3DS·2VL, this trait did not appear. The gene controlling the tufted bristles was located on 2VS. Gametocidal chromosome 3C of Aegilops triuncialis could successfully induce chromosome 2V structural changes.

  15. Solvent substitution

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    The DOE Environmental Restoration and Waste Management Office of Technology Development and the Air Force Engineering and Services Center convened the First Annual International Workshop on Solvent Substitution on December 4--7, 1990. The primary objectives of this joint effort were to share information and ideas among attendees in order to enhance the development and implementation of required new technologies for the elimination of pollutants associated with industrial use of hazardous and toxic solvents; and to aid in accelerating collaborative efforts and technology transfer between government and industry for solvent substitution. There were workshop sessions focusing on Alternative Technologies, Alternative Solvents, Recovery/Recycling, Low VOC Materials and Treatment for Environmentally Safe Disposal. The 35 invited papers presented covered a wide range of solvent substitution activities including: hardware and weapons production and maintenance, paint stripping, coating applications, printed circuit boards, metal cleaning, metal finishing, manufacturing, compliance monitoring and process control monitoring. This publication includes the majority of these presentations. In addition, in order to further facilitate information exchange and technology transfer, the US Air Force and DOE solicited additional papers under a general Call for Papers.'' These papers, which underwent review and final selection by a peer review committee, are also included in this combined Proceedings/Compendium. For those involved in handling, using or managing hazardous and toxic solvents, this document should prove to be a valuable resource, providing the most up-to-date information on current technologies and practices in solvent substitution. Individual papers are abstracted separated.

  16. Synthetic chromosomes.

    Science.gov (United States)

    Schindler, Daniel; Waldminghaus, Torsten

    2015-11-01

    What a living organism looks like and how it works and what are its components-all this is encoded on DNA, the genetic blueprint. Consequently, the way to change an organism is to change its genetic information. Since the first pieces of recombinant DNA have been used to transform cells in the 1970s, this approach has been enormously extended. Bigger and bigger parts of the genetic information have been exchanged or added over the years. Now we are at a point where the construction of entire chromosomes becomes a reachable goal and first examples appear. This development leads to fundamental new questions, for example, about what is possible and desirable to build or what construction rules one needs to follow when building synthetic chromosomes. Here we review the recent progress in the field, discuss current challenges and speculate on the appearance of future synthetic chromosomes.

  17. Associations between Variation in X Chromosome Male Reproductive Genes and Sperm Competitive Ability in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Leah Greenspan

    2011-01-01

    Full Text Available Variation in reproductive success has long been thought to be mediated in part by genes encoding seminal proteins. Here we explore the effect on male reproductive phenotypes of X-linked polymorphisms, a chromosome that is depauperate in genes encoding seminal proteins. Using 57 X chromosome substitution lines, sperm competition was tested both when the males from the wild-extracted line were the first to mate (“defense” crosses, followed by a tester male, and when extracted-line males were the second to mate, after a tester male (“offfense” crosses. We scored the proportion of progeny sired by each male, the fecundity, the remating rate and refractoriness to remating, and tested the significance of variation among lines. Eleven candidate genes were chosen based on previous studies, and portions of these genes were sequenced in all 57 lines. A total of 131 polymorphisms were tested for associations with the reproductive phenotypes using linear models. Nine polymorphisms in 4 genes were found to show significant associations (at a 5% FDR. Overall, it appears that the X chromosomes harbor abundant variation in sperm competition, especially considering the paucity of seminal protein genes. This suggests that much of the male reproductive variation lies outside of genes that encode seminal proteins.

  18. [Dicentric Y chromosome].

    Science.gov (United States)

    Abdelmoula, N Bouayed; Amouri, A

    2005-01-01

    Dicentric Y chromosomes are the most common Y structural abnormalities and their influence on gonadal and somatic development is extremely variable. Here, we report the third comprehensive review of the literature concerning dicentric Y chromosomes reported since 1994. We find 78 new cases for which molecular studies (PCR or FISH) have been widely applied to investigate SRY (68% of cases), GBY, ZFY, RFS4Y, GCY and different genes at AZF region. For dic(Yq), all cases (n = 20) were mosaic for 45,X and 4 of them were also mosaic for a 46,XY cell line. When breakpoints were available (15/20 cases), they were in Yp11. 50% of cases were phenotypic female and 20% phenotypic male while 20% of cases were reported with gonadal dysgenesis. Gonadal histology was defined in 8 cases but only in one case, gonadal tissu was genetically investigated because of gonadoblastoma. For dic(Yp) (n = 55), mosaicism concerned only 45,X cell line and was found in 50 cases while the remainder five cases were homogeneous. When breakpoints were available, it was at Yq11 in 50 cases and at Yq12 in two cases. 54% of cases were phenotypic female, 26% were phenotypic male and 18% were associated with genitalia ambiguous. SRY was analyzed in 33 cases, sequenced in 9 cases and was muted in only one case. Gonads were histologically explored in 34 cases and genetically investigated in 8 cases. Gonadoblastoma was found in only two cases. Through this review, it seems that phenotype-genotype correlations are still not possible and that homogeneous studies of dic(Y) in more patients using molecular tools for structural characterization of the rearranged Y chromosome and assessment of mosaicism in many organs are necessary to clarify the basis of the phenotypic heterogeneity of dicentric Y chromosomes and then to help phenotypic prediction of such chromosome rearrangement.

  19. Substituting complements

    OpenAIRE

    Dari-Mattiacci, G.; Parisi, F.; Heller, M.

    2009-01-01

    The presence of multiple sellers in the provision of (nonsubstitutable) complementary goods leads to outcomes that are worse than those generated by a monopoly (with a vertically integrated production of complements), a problem known in the economic literature as complementary oligopoly and recently popularized in the legal literature as the tragedy of the anticommons. We ask the following question: how many substitutes for each complement are necessary to render the presence of multiple sell...

  20. Morphologic, immunologic, enzymehistochemical and chromosomal analysis of a cell line derived from Hodgkin's disease : Evidence for a B-cell origin of Sternberg-Reed cells

    NARCIS (Netherlands)

    Poppema, Sibrand; de Jong, Bauke; Atmosoerodjo, Jane; Idenburg, Vera; Visser, Lydia; de Ley, Lou

    1985-01-01

    Cell lines derived from Hodgkin's disease may provide a clue to the nature of Sternberg-Reed cells. In the current study, the establishment of an Epstein-Barr-virus-negative lymphoblastoid cell line, derived from the pleural fluid of a patient with the nodular sclerosis type of Hodgkin's disease, is

  1. Chromosomal patterns in human malignant astrocytomas.

    Science.gov (United States)

    Rey, J A; Bello, M J; de Campos, J M; Kusak, M E; Ramos, C; Benitez, J

    1987-12-01

    Cytogenetic analysis by direct and/or in vitro preparations was performed on 34 malignant astrocytomas. Thirty tumors showed near-diploid chromosome numbers, whereas, tritetraploid chromosome complements were present in four tumors. The most frequent chromosomal changes implied numerical deviations by a gain of chromosomes #7, #19, and #20, and by losses of #10, #22, and Y. Structural rearrangements were present in stem- or side lines of 24 tumors. Although no common chromosomal rearrangement seems to exist among those tumors, chromosomes #1, #6, #7, and #9 were predominantly involved. Polysomy and structural rearrangements of chromosome #7 could be related to the overexpression of epidermal growth factor gene, previously observed in some malignant gliomas.

  2. Temporal genomic evolution of bird sex chromosomes

    DEFF Research Database (Denmark)

    Wang, Zongji; Zhang, Jilin; Yang, Wei;

    2014-01-01

    BACKGROUND: Sex chromosomes exhibit many unusual patterns in sequence and gene expression relative to autosomes. Birds have evolved a female heterogametic sex system (male ZZ, female ZW), through stepwise suppression of recombination between chrZ and chrW. To address the broad patterns and complex...... driving forces of Z chromosome evolution, we analyze here 45 newly available bird genomes and four species' transcriptomes, over their course of recombination loss between the sex chromosomes. RESULTS: We show Z chromosomes in general have a significantly higher substitution rate in introns and synonymous...... ('fast-Z' evolution). And species with a lower level of intronic heterozygosities tend to evolve even faster on the Z chromosome. Further analysis of fast-evolving genes' enriched functional categories and sex-biased expression patterns support that, fast-Z evolution in birds is mainly driven by genetic...

  3. Temporal genomic evolution of bird sex chromosomes

    DEFF Research Database (Denmark)

    Wang, Zongji; Zhang, Jilin; Yang, Wei;

    2014-01-01

    BACKGROUND: Sex chromosomes exhibit many unusual patterns in sequence and gene expression relative to autosomes. Birds have evolved a female heterogametic sex system (male ZZ, female ZW), through stepwise suppression of recombination between chrZ and chrW. To address the broad patterns and complex...... driving forces of Z chromosome evolution, we analyze here 45 newly available bird genomes and four species' transcriptomes, over their course of recombination loss between the sex chromosomes. RESULTS: We show Z chromosomes in general have a significantly higher substitution rate in introns and synonymous...... changes with that of introns, between chrZ and autosomes or regions with increasing ages of becoming Z-linked, therefore codon usage bias in birds is probably driven by the mutational bias. On the other hand, Z chromosomes also evolve significantly faster at nonsynonymous sites relative to autosomes...

  4. Influence of commorn smut and anti-tumor screening of substitution lines%玉米染色体片段代换系对瘤黑粉病的抗性研究

    Institute of Scientific and Technical Information of China (English)

    吕爱枝; 王立秋; 曹熙敏; 张晓光

    2011-01-01

    Common smut in maize reduces grain yield greatly. lines play an importment role to minimize the losses caused by common smut. At the elongation stage, Ustilago maydis fungus was injected into 8 maize chromosome segment introgress lines( CSILs). Eight CSILs have different chromosome segments of donor maize HB522 respectively. There are four kinds of varieties in eight CSILs. is highly resist to common smut. Chr3-7's grain yield is highest among other seven CSILs and two parents. chr3-7 is good SSILs for Resistance to common smut study and resistance breeding.%玉米瘤黑粉病能造成玉米严重减产,抗性系的选育对于减少病害具有重要价值.本研究在拔节期采用注射法接种瘤黑粉孢子,对第三染色体的8个染色体片段代换系进行抗性研究.结果表明,8个染色体片段代换系被代换的供体片段位点不同.抗瘤黑粉病表型有4种变异.其中,chr3-7系发病率、病级和病情指数均为0,表现高抗.与其他染色体片段代换系、Z3受体亲本及HB522供体亲本相比,ehr3-7系产量高,接种瘤黑粉孢子与对照产量差异不显著.chr3-7系对于抗瘤黑粉病遗传研究和育种具有重要意义.

  5. Cytological and Morphological Characteristics of Hybrids Between Lophopyrum elongatum 1E Addition Line and Gametocidal Chromosome 2C Addition Line%长穗偃麦草1E附加系与杀配子染色体2C附加系杂交后代的细胞学及形态学分析

    Institute of Scientific and Technical Information of China (English)

    刘春影; 杨蕾; 王丹; 郭长虹

    2012-01-01

    Lophopyrum elongatum is a wild relative of wheat that has excellent traits such as cold resistance, drought resistance and disease resistance. In order to transfer the desirable genes of Th. elongatum into wheat, hybrid, selfing and backcross were done between 'Chinese spring' -Th. elongatum IE disomic addition line and 'Chinese spring' -Ae. cylindrica gametocidal chromosome 2C disomic addition line, the cytological and morphological characteristics of offspring were observed. Chromosome aberrations were observed in the mitosis and meiosis, the seed-setting rate of Fi was lower significantly compared with parents, the spike separation was observed in the hybrids, in addition to the normal spike, we also observed the compactoid. This study showed that, gametocidal chromosome 2C could induce chromosome aberrations and had a certain influence to seed-setting rate and spike. These results provided a good basis for further developing wheat- Th. elongatum IE chromosome translocation and deletion lines.%长穗偃麦草是小麦的野生近缘种属,具有抗寒、抗旱、抗病等优异性状.为了利用长穗偃麦草的优异基因,将“中国春’-长穗偃麦草1E二体附加系与‘中国春’-柱穗山羊草2C二体附加系杂交、自交和回交,观察其后代的细胞学和形态学特性.结果表明,在杂交后代有丝分裂和减数分裂中观察到了染色 体畸变现象;统计F1代自交结实率,发现与亲本相比,这些杂种后代的结实率明显降低;杂种后代的穗型 发生了分离,除正常穗型外还观察到了密穗型,说明杀配子染色体2C可以诱导染色体畸变并对结实率 和穗型均有一定的影响.本研究为进一步创制小麦-长穗偃麦草1E染色体易位系和缺失系奠定了基础.

  6. Molecular definition of a chromosome 9p21 germ-line deletion in a woman with multiple melanomas and a plexiform neurofibroma: implications for 9p tumor-suppressor gene(s).

    Science.gov (United States)

    Petty, E M; Gibson, L H; Fountain, J W; Bolognia, J L; Yang-Feng, T L; Housman, D E; Bale, A E

    1993-01-01

    Cutaneous malignant melanoma (CMM) is often familial, but the mode of inheritance and the chromosomal location of melanoma susceptibility locus are controversial. Identification of a 34-year-old woman with eight primary malignant melanomas, multiple atypical moles, and a de novo constitutional cytogenetic rearrangement involving chromosomes 5p and 9p suggested the presence of a melanoma predisposition gene at one of these locations. A high-resolution karyotype showed a partial deletion of a dark-staining Giemsa band, either 5p14 or 9p21. The patient was heterozygous for five 5p14 RFLPs. In situ hybridization with D9S3 indicated that this 9p21 marker was deleted. Gene dosage studies demonstrated the deletion of two more distal 9p21 markers, D9S126 and IFNA. In addition, she was hemizygous for the more proximal 9p21 short tandem-repeat polymorphism at D9S104. D9S18, D9S19, and D9S33 were retained, localizing the deletion to 9p21 between D9S19 on the proximal side and D9S33 on the distal side. Pulsed-field gel electrophoresis with D9S19 and D9S33 did not reveal any junction fragments in the patient's DNA. This germ-line deletion suggests that mutations in a 9p21 gene may initiate melanoma tumorigenesis. Images Figure 1 Figure 2 Figure 3 PMID:8317504

  7. Molecular definition of a chromosome 9p21 germ-line deletion in a woman with multiple melanomas and a plexiform neurofibroma: Implications for 9p tumor-suppressor gene(s)

    Energy Technology Data Exchange (ETDEWEB)

    Petty, E.M.; Gibson, L.H.; Yang-Feng, T.L.; Bale, A.E.; Bolognia, J.L. (Yale Univ. School of Medicine, New Haven, CT (United States)); Fountain, J.W.; Housman, D.E. (Massachusetts Institute of Technology, Cambridge (United States))

    1993-07-01

    Cutaneous malignant melanoma (CMM) is often familial, but the mode of inheritance and the chromosomal location of a melanoma susceptibility locus are controversial. Identification of a 34-year-old woman with eight primary malignant melanomas, multiple atypical moles, and a de novo constitutional cytogenetic rearrangement involving chromosomes 5p and 9p suggested the presence of a melanoma predisposition gene at one of these locations. A high-resolution karyotype showed a partial deletion of a dark-staining Giemsa band, either 5p14 or 9p21. The patient was heterozygous for five 5p14 RFLPs. In situ hybridization with D9S3 indicated that this 9p21 marker was deleted. Gene dosage studies demonstrated the deletion of two more distal 9p21 markers, D9S126 and IFNA. In addition, she was hemizygous for the more proximal 9p21 short tandem-repeat polymorphism at D9S104. D9S18, D9S19, and D9S33 were retained, localizing the deletion to 9p21 between D9S19 on the proximal side and D9S33 on the distal side. Pulsed-field gel electrophoresis with D9S19 and D9S33 did not reveal any junction fragments in the patient's DNA. This germ-line deletion suggests that mutations in a 9p21 gene may initiate melanoma tumorigenesis. 39 refs., 4 figs., 1 tab.

  8. Development and Identification of Wheat Haynaldia villosa 6DL/6VS Translocation Lines with Powdery Mildew Resistance

    Institute of Scientific and Technical Information of China (English)

    Li Hui; Chen Xiao; Xin Zhiyong; Ma Youzhi; Xu Huijun

    2000-01-01

    Wheat-H. villosa 6DL/6VS translocation lines, Pm97033, Pm97034 and Pm97035 developed by(TH3/4 ×Wan7107)F1 young embryo and anther culture, were evaluated by powdery mildew resistance test, cytogenetic analysis, biochemical analysis, and in situ hybridization respectively. Pm97033 and its hybrids crossing with susceptible cultivar Wan7107, 6D/6V substitution line and double ditelocentric lines (DDT) of Chinese Spring(C S)6A, 6B and 6D were all immune to powdery mildew through the growing period. It was with the somatic chromosome number of 42 and twenty-one bivalents at M I in pollen mother cells (PMCs M I ). The configurations at pMCs M I in hybrids F1 of Pm97033 with either susceptible cultivar or 6D/6V substitution line were 21 biva lents. In hybrids F1 between Pm97033 and C S 6A, 6B DDT, twenty bivalents and one allo-trivalent (t I t)composing of one univalent and two telocentric chromosomes were observed at PMCs M I . The configuration between Pm97033 and C S 6D DDT was twenty bivalents, one allo-bivalent (I t)and one telocentric chromosome. The results of cytogenetic analysis showed that Pm97033 was a translocation line , and the translocation was related to chromosome 6D. The results of in situ hybridization between probe labeled with biotin of H. villosa total DNA and the chromosomes showed that the three lines were all Robertsonian translocation lines. Glutamate oxaloacetate transaminase (GOT)isozyrme analyses showed that the translocation lines expressed the same pattern with C S,and without the specific band of 6VL of H. villas compared with substitution line and addition line. In α-zone of gliadin-2 pattern, all lines resistant to powdery mildew expressed an identical specific band encoded by the gene located on 6VS of H. villosa. All the cytogenetic and biochemical analysis confirmed that Pm97033, etc. were 6DL/6VS translocation lines with the substitution of 6VS for 6DS.

  9. Chromosome-specific segmentation revealed by structural analysis of individually isolated chromosomes.

    Science.gov (United States)

    Kitada, Kunio; Taima, Akira; Ogasawara, Kiyomoto; Metsugi, Shouichi; Aikawa, Satoko

    2011-04-01

    Analysis of structural rearrangements at the individual chromosomal level is still technologically challenging. Here we optimized a chromosome isolation method using fluorescent marker-assisted laser-capture and laser-beam microdissection and applied it to structural analysis of two aberrant chromosomes found in a lung cancer cell line. A high-density array-comparative genomic hybridization (array-CGH) analysis of DNA samples prepared from each of the chromosomes revealed that these two chromosomes contained 296 and 263 segments, respectively, ranging from 1.5 kb to 784.3 kb in size, derived from different portions of chromosome 8. Among these segments, 242 were common in both aberrant chromosomes, but 75 were found to be chromosome-specific. Sequences of 263 junction sites connecting the ends of segments were determined using a PCR/Sanger-sequencing procedure. Overlapping microhomologies were found at 169 junction sites. Junction partners came from various portions of chromosome 8 and no biased pattern in the positional distribution of junction partners was detected. These structural characteristics suggested the occurrence of random fragmentation of the entire chromosome 8 followed by random rejoining of these fragments. Based on that, we proposed a model to explain how these aberrant chromosomes are formed. Through these structural analyses, it was demonstrated that the optimized chromosome isolation method described here can provide high-quality chromosomal DNA for high resolution array-CGH analysis and probably for massively parallel sequencing analysis.

  10. Establishment and characterization of A novel Philadelphia-chromosome positive chronic myeloid leukemia cell line, TCC-S, expressing P210 and P190 BCR/ABL transcripts but missing normal ABL gene.

    Science.gov (United States)

    Van, Phan Nguyen Thanh; Xinh, Phan Thi; Kano, Yasuhiko; Tokunaga, Katsushi; Sato, Yuko

    2005-03-01

    A novel Philadelphia-chromosome positive (Ph+) cell line, TCC-S, has been established from a patient with Ph+ chronic myeloid leukemia (CML) in the blastic crisis. TCC-S cells were shown to express both P210 and P190 BCR/ABL transcripts by reverse transcriptase-polymerase chain reaction (PCR), although quantitative-PCR revealed that TCC-S cells mainly expressed P210 BCR/ABL transcript. Karyotype analysis revealed several triploid clones which constantly harbored two der(9)del(9) (p12)t(9;22) (q34;qll)s and two del(9) (q21)s. The der(9)del(9) (p12)t(9;22) (q34;q11) is rarely found in other CML cell lines. Moreover, to the best of our knowledge, del(9) (q21) resulting in missing of a restrict region including normal ABL gene has not been found among CML cell lines previously described. Thus, TCC-S cells with only BCR/ABL gene and no normal ABL gene may be a useful tool for functional study of ABL in Ph+ CML.

  11. A Geometric Approach For Fully Automatic Chromosome Segmentation

    CERN Document Server

    Minaee, Shervin; Khalaj, Babak Hossein

    2011-01-01

    Chromosome segmentation is a fundamental task in human chromosome analysis. Most of previous methods for separation between touching chromosomes require human intervention. In this paper, a geometry based method is used for automatic chromosome segmentation. This method can be divided into two phases. In the first phase, chromosome clusters are detected using three geometric criteria and in the second phase chromosome clusters are separated using a proper cut line. However, most earlier methods do not work well with chromosome clusters that contain more than two chromosomes. Our method, on the other hand, has a high efficiency in separation of chromosome clusters in such scenarios. Another advantage of the proposed method is that it can easily apply to any type of images such as binary images. This is due to the fact that the proposed scheme uses the geometric features of chromosomes which are independent of the type of images. The performance of the proposed scheme is demonstrated on a database containing to...

  12. Chromosomal location of genes for novel glutenin subunits and gliadins in wild emmer wheat (Triticum turgidum L. var. dicoccoides).

    Science.gov (United States)

    Xu, S S; Khan, K; Klindworth, D L; Faris, J D; Nygard, G

    2004-05-01

    The glutenin and gliadin proteins of wild emmer wheat, Triticum turgidum L. var. dicoccoides, have potential for improvement of durum wheat ( T. turgidum L. var. durum) quality. The objective of this study was to determine the chromosomes controlling the high molecular weight (HMW) glutenin subunits and gliadin proteins present in three T. turgidum var. dicoccoides accessions (Israel-A, PI-481521, and PI-478742), which were used as chromosome donors in Langdon durum- T. turgidum var. dicoccoides (LDN-DIC) chromosome substitution lines. The three T. turgidum var. dicoccoides accessions, their respective LDN-DIC substitution lines, and a number of controls with known HMW glutenin subunits were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), urea/SDS-PAGE, and acid polyacrylamide gel electrophoresis (A-PAGE). The results revealed that all three T. turgidum var. dicoccoides accessions possess Glu-A1 alleles that are the same as or similar to those reported previously. However, each T. turgidum var. dicoccoides accession had a unique Glu-B1 allele. PI-478742 had an unusual 1Bx subunit, which had mobility slightly slower than the 1Ax subunit in 12% SDS-PAGE gels. The subunits controlled by chromosome 1B of PI-481521 were slightly faster in mobility than the subunits of the Glu-B1n allele, and the 1By subunit was identified as band 8. The 1B subunits of Israel-A had similar mobility to subunits 14 and 16. The new Glu-B1 alleles were designated as Glu-B1be in Israel-A, Glu-B1bf in PI-481521, and Glu-B1bg in PI-478742. Results from A-PAGE revealed that PI-481521, PI-478742, and Israel-A had eight, 12, and nine unique gliadin bands, respectively, that were assigned to specific chromosomes. The identified glutenin subunits and gliadin proteins in the LDN-DIC substitution lines provide the basis for evaluating their effects on end-use quality, and they are also useful biochemical markers for identifying specific chromosomes or chromosome

  13. Broader utilization of origins of DNA replication in cancer cell lines along a 78 kb region of human chromosome 2q34.

    Science.gov (United States)

    Valenzuela, Manuel S; Hu, Lan; Lueders, John; Walker, Robert; Meltzer, Paul S

    2012-01-01

    Human DNA replication depends on the activation of thousands of origins distributed within the genome. The actual distribution of origins is not known, nor whether this distribution is unique to a cell type, or if it changes with the proliferative state of the cell. In this study, we have employed a real-time PCR-based nascent strand DNA abundance assay, to determine the location of origins along a 78 kb region on Chr2q34. Preliminary studies using nascent DNA strands isolated from either HeLa and normal skin fibroblast cells showed that in both cell lines peaks of high origin activity mapped in similar locations. However, the overall origin profile in HeLa cells corresponded to broad origin activation zones, whereas in fibroblasts a more punctuated profile of origin activation was observed. To investigate the relevance of this differential origin profile, we compared the origin distribution profiles in breast cancer cell lines MDA-MB-231, BT-474, and MCF-7, to their normal counterpart MCF-10A. In addition, the CRL7250 cell line was also used as a normal control. Our results validated our earlier observation and showed that the origin profile in normal cell lines exhibited a punctuated pattern, in contrast to broader zone profiles observed in the cancer cell lines. A quantitative analysis of origin peaks revealed that the number of activated origins in cancer cells is statistically larger than that obtained in normal cells, suggesting that the flexibility of origin usage is significantly increased in cancer cells compared to their normal counterparts.

  14. Cytogenetic and Molecular Characterization of B-Genome Introgression Lines of Brassica napus L.

    Science.gov (United States)

    Dhaliwal, Inderpreet; Mason, Annaliese S.; Banga, Shashi; Bharti, Sakshi; Kaur, Beerpal; Gurung, Allison Mary; Salisbury, Phillip Anthony; Batley, Jacqueline; Banga, Surinder Singh

    2016-01-01

    Brassica napus introgression lines (ILs), having B-genome segments from B. carinata, were assessed genetically for extent of introgression and phenotypically for siliqua shatter resistance. Introgression lines had 7–9% higher DNA content, were meiotically stable, and had almost normal pollen fertility/seed set. Segment introgressions were confirmed by fluorescent genomic in situ hybridization (fl-GISH), SSR analyses, and SNP studies. Genotyping with 48 B-genome specific SSRs detected substitutions from B3, B4, B6, and B7 chromosomes on 39 of the 69 ILs whereas SNP genotyping detected a total of 23 B-segments (≥3 Mb) from B4, B6, and B7 introgressed into 10 of the 19 (C1, C2, C3, C5, C6, C8, C9, A3, A9, A10) chromosomes in 17 ILs. The size of substitutions varied from 3.0 Mb on chromosome A9 (IL59) to 42.44 Mb on chromosome C2 (IL54), ranging from 7 to 83% of the recipient chromosome. Average siliqua strength in ILs was observed to be higher than that of B. napus parents (2.2–6.0 vs. 1.9–4.0 mJ) while siliqua strength in some of the lines was almost equal to that of the donor parent B. carinata (6.0 vs.7.2 mJ). These ILs, with large chunks of substituted B-genome, can prove to be a useful prebreeding resource for germplasm enhancement in B. napus, especially for siliqua shatter resistance. PMID:27821632

  15. GSK-3 inhibitors induce chromosome instability

    Directory of Open Access Journals (Sweden)

    Staples Oliver D

    2007-08-01

    Full Text Available Abstract Background Several mechanisms operate during mitosis to ensure accurate chromosome segregation. However, during tumour evolution these mechanisms go awry resulting in chromosome instability. While several lines of evidence suggest that mutations in adenomatous polyposis coli (APC may promote chromosome instability, at least in colon cancer, the underlying mechanisms remain unclear. Here, we turn our attention to GSK-3 – a protein kinase, which in concert with APC, targets β-catenin for proteolysis – and ask whether GSK-3 is required for accurate chromosome segregation. Results To probe the role of GSK-3 in mitosis, we inhibited GSK-3 kinase activity in cells using a panel of small molecule inhibitors, including SB-415286, AR-A014418, 1-Azakenpaullone and CHIR99021. Analysis of synchronised HeLa cells shows that GSK-3 inhibitors do not prevent G1/S progression or cell division. They do, however, significantly delay mitotic exit, largely because inhibitor-treated cells have difficulty aligning all their chromosomes. Although bipolar spindles form and the majority of chromosomes biorient, one or more chromosomes often remain mono-oriented near the spindle poles. Despite a prolonged mitotic delay, anaphase frequently initiates without the last chromosome aligning, resulting in chromosome non-disjunction. To rule out the possibility of "off-target" effects, we also used RNA interference to selectively repress GSK-3β. Cells deficient for GSK-3β exhibit a similar chromosome alignment defect, with chromosomes clustered near the spindle poles. GSK-3β repression also results in cells accumulating micronuclei, a hallmark of chromosome missegregation. Conclusion Thus, not only do our observations indicate a role for GSK-3 in accurate chromosome segregation, but they also raise the possibility that, if used as therapeutic agents, GSK-3 inhibitors may induce unwanted side effects by inducing chromosome instability.

  16. The DNA sequence of the human X chromosome

    OpenAIRE

    Ross, Mark T.; Grafham, Darren V.; Coffey, Alison J; Scherer, Steven; McLay, Kirsten; Muzny, Donna; Platzer, Matthias; Howell, Gareth R.; Burrows, Christine; Bird, Christine P.; Frankish, Adam; Lovell, Frances L.; Howe, Kevin L; Jennifer L Ashurst; Fulton, Robert S.

    2005-01-01

    The human X chromosome has a unique biology that was shaped by its evolution as the sex chromosome shared by males and females. We have determined 99.3% of the euchromatic sequence of the X chromosome. Our analysis illustrates the autosomal origin of the mammalian sex chromosomes, the stepwise process that led to the progressive loss of recombination between X and Y, and the extent of subsequent degradation of the Y chromosome. LINE1 repeat elements cover one-third of the X chromosome, with a...

  17. Geographical changes in relative frequency of inversions in chromosome III of Drosophila pseudoobscura among natural populations from Mexico

    Directory of Open Access Journals (Sweden)

    Salceda Víctor M.

    2009-01-01

    Full Text Available Chromosomal polymorphism in natural populations of Drosophila pseudoobscura have been broadly studied in the USA but scarcely in Mexico where only about 60 localities have been analyzed. Differences among both regions are notorious with respect to their chromosomal constitution. Northern populations, those of USA, have as representative inversions the sequences ST, AR and CH contrasting with those in Southern populations (Mexico in which prevail the gene arrangements TL, CU and SC. Assuming as a probable mechanism that has allowed these substitutions the flow generated by the presence of a North - South clines, we took as a goal find out if such clines really exist. With that objective in mind we studied 29 populations of this species distributed along four North - South transects. Specimens of D. pseudoobscura caught by attracting them with fermenting bananas were carried to the laboratory where from each female an isofemale line was established. When their offspring appeared a single larva from each isofemale was taken, its salivary glands extracted and stained with a solution of lacto-aceto- orcein, by these means the polytene chromosomes were obtained. On these chromosomes we identified, for each larva, the inversion (s carried in the third chromosome, in such a way 3439 third chromosomes were analyzed. Among the 29 localities we identified 17 different inversions but the number of them varied from population to population from three to eleven. Relative frequencies of each inversion at every location were calculated and with them for each transect the presence or absence of clines was determined. Among each transect the existence of clines was observed only between two or three near by populations, but we were not able to find a clear manifestation of the presence of clines along a complete transect. Our results at this respect are similar to those previously reported for USA populations. A mechanism that explains North - South substitutions

  18. Artificial Skin – Culturing of Different Skin Cell Lines for Generating an Artificial Skin Substitute on Cross-Weaved Spider Silk Fibres

    Science.gov (United States)

    Reimers, Kerstin; Kuhbier, Joern W.; Schäfer-Nolte, Franziska; Allmeling, Christina; Kasper, Cornelia; Vogt, Peter M.

    2011-01-01

    Background In the field of Plastic Reconstructive Surgery the development of new innovative matrices for skin repair is in urgent need. The ideal biomaterial should promote attachment, proliferation and growth of cells. Additionally, it should degrade in an appropriate time period without releasing harmful substances, but not exert a pathological immune response. Spider dragline silk from Nephila spp meets these demands to a large extent. Methodology/Principal Findings Native spider dragline silk, harvested directly out of Nephila spp spiders, was woven on steel frames. Constructs were sterilized and seeded with fibroblasts. After two weeks of cultivating single fibroblasts, keratinocytes were added to generate a bilayered skin model, consisting of dermis and epidermis equivalents. For the next three weeks, constructs in co-culture were lifted on an originally designed setup for air/liquid interface cultivation. After the culturing period, constructs were embedded in paraffin with an especially developed program for spidersilk to avoid supercontraction. Paraffin cross- sections were stained in Haematoxylin & Eosin (H&E) for microscopic analyses. Conclusion/Significance Native spider dragline silk woven on steel frames provides a suitable matrix for 3 dimensional skin cell culturing. Both fibroblasts and keratinocytes cell lines adhere to the spider silk fibres and proliferate. Guided by the spider silk fibres, they sprout into the meshes and reach confluence in at most one week. A well-balanced, bilayered cocultivation in two continuously separated strata can be achieved by serum reduction, changing the medium conditions and the cultivation period at the air/liquid interphase. Therefore spider silk appears to be a promising biomaterial for the enhancement of skin regeneration. PMID:21814557

  19. Artificial skin--culturing of different skin cell lines for generating an artificial skin substitute on cross-weaved spider silk fibres.

    Directory of Open Access Journals (Sweden)

    Hanna Wendt

    Full Text Available BACKGROUND: In the field of Plastic Reconstructive Surgery the development of new innovative matrices for skin repair is in urgent need. The ideal biomaterial should promote attachment, proliferation and growth of cells. Additionally, it should degrade in an appropriate time period without releasing harmful substances, but not exert a pathological immune response. Spider dragline silk from Nephila spp meets these demands to a large extent. METHODOLOGY/PRINCIPAL FINDINGS: Native spider dragline silk, harvested directly out of Nephila spp spiders, was woven on steel frames. Constructs were sterilized and seeded with fibroblasts. After two weeks of cultivating single fibroblasts, keratinocytes were added to generate a bilayered skin model, consisting of dermis and epidermis equivalents. For the next three weeks, constructs in co-culture were lifted on an originally designed setup for air/liquid interface cultivation. After the culturing period, constructs were embedded in paraffin with an especially developed program for spidersilk to avoid supercontraction. Paraffin cross-sections were stained in Haematoxylin & Eosin (H&E for microscopic analyses. CONCLUSION/SIGNIFICANCE: Native spider dragline silk woven on steel frames provides a suitable matrix for 3 dimensional skin cell culturing. Both fibroblasts and keratinocytes cell lines adhere to the spider silk fibres and proliferate. Guided by the spider silk fibres, they sprout into the meshes and reach confluence in at most one week. A well-balanced, bilayered cocultivation in two continuously separated strata can be achieved by serum reduction, changing the medium conditions and the cultivation period at the air/liquid interphase. Therefore spider silk appears to be a promising biomaterial for the enhancement of skin regeneration.

  20. Unusual maternal uniparental isodisomic x chromosome mosaicism with asymmetric y chromosomal rearrangement.

    Science.gov (United States)

    Lee, B Y; Kim, S Y; Park, J Y; Choi, E Y; Kim, D J; Kim, J W; Ryu, H M; Cho, Y H; Park, S Y; Seo, J T

    2014-01-01

    Infertile men with azoospermia commonly have associated microdeletions in the azoospermia factor (AZF) region of the Y chromosome, sex chromosome mosaicism, or sex chromosome rearrangements. In this study, we describe an unusual 46,XX and 45,X mosaicism with a rare Y chromosome rearrangement in a phenotypically normal male patient. The patient's karyotype was 46,XX[50]/45,X[25]/46,X,der(Y)(pter→q11.222::p11.2→pter)[25]. The derivative Y chromosome had a deletion at Yq11.222 and was duplicated at Yp11.2. Two copies of the SRY gene were confirmed by fluorescence in situ hybridization analysis, and complete deletion of the AZFb and AZFc regions was shown by multiplex-PCR for microdeletion analysis. Both X chromosomes of the predominant mosaic cell line (46,XX) were isodisomic and derived from the maternal gamete, as determined by examination of short tandem repeat markers. We postulate that the derivative Y chromosome might have been generated during paternal meiosis or early embryogenesis. Also, we suggest that the very rare mosaicism of isodisomic X chromosomes might be formed during maternal meiosis II or during postzygotic division derived from the 46,X,der(Y)/ 45,X lineage because of the instability of the derivative Y chromosome. To our knowledge, this is the first confirmatory study to verify the origin of a sex chromosome mosaicism with a Y chromosome rearrangement.

  1. Engineered human dicentric chromosomes show centromere plasticity.

    Science.gov (United States)

    Higgins, Anne W; Gustashaw, Karen M; Willard, Huntington F

    2005-01-01

    The centromere is essential for the faithful distribution of a cell's genetic material to subsequent generations. Despite intense scrutiny, the precise genetic and epigenetic basis for centromere function is still unknown. Here, we have used engineered dicentric human chromosomes to investigate mammalian centromere structure and function. We describe three classes of dicentric chromosomes isolated in different cell lines: functionally monocentric chromosomes, in which one of the two genetically identical centromeres is consistently inactivated; functionally dicentric chromosomes, in which both centromeres are consistently active; and dicentric chromosomes heterogeneous with respect to centromere activity. A study of serial single cell clones from heterogeneous cell lines revealed that while centromere activity is usually clonal, the centromere state (i.e. functionally monocentric or dicentric) in some lines can switch within a growing population of cells. Because pulsed field gel analysis indicated that the DNA at the centromeres of these chromosomes did not change detectably, this switching of the centromere state is most likely due to epigenetic changes. Inactivation of one of the two active centromeres in a functionally dicentric chromosome was observed in a percentage of cells after treatment with Trichostatin A, an inhibitor of histone deacetylation. This study provides evidence that the activity of human centromeres, while largely stable, can be subject to dynamic change, most likely due to epigenetic modification.

  2. Characterization and mapping of QTLs on chromosome 2D for grain size and yield traits using a mutant line induced by EMS in wheat

    Institute of Scientific and Technical Information of China (English)

    Guizhi; Zhang; Yingying; Wang; Ying; Guo; Yan; Zhao; Fanmei; Kong; Sishen; Li

    2015-01-01

    Production of mutants with altered phenotypes is a powerful approach for determining the biological functions of genes in an organism. In this study, a high-grain-weight mutant line M8008 was identified from a library of mutants of the common wheat cultivar YN15 treated with ethylmethane sulfonate(EMS). F2 and F2:3generations produced from crosses of M8008 × YN15(MY) and M8008 × SJZ54(MS) were used for genetic analysis. There were significant differences between M8008 and YN15 in plant height(PH), spike length(SL),fertile spikelet number per spike(FSS), grain width(GW), grain length(GL), GL/GW ratio(GLW), and thousand-grain weight(TGW). Most simple correlation coefficients were significant for the investigated traits, suggesting that the correlative mutations occurred in M8008. Approximately 21% of simple sequence repeat(SSR) markers showed polymorphisms between M8008 and YN15, indicating that EMS can induce a large number of mutated loci. Twelve quantitative trait loci(QTLs) forming QTL clusters(one in MY and two in MS) were detected. The QTL clusters coinciding with(MY population) or near(MS population) the marker wmc41 were associated mainly with grain-size traits, among which the M8008 locus led to decreases in GW, factor form density(FFD), and TGW and to increases in GLW. The cluster in the wmc25–barc168 interval in the MS population was associated with yield traits, for which the M8008 locus led to decreased PH, spike number per plant(SN), and SL.

  3. Male-biased aganglionic megacolon in the TashT mouse line due to perturbation of silencer elements in a large gene desert of chromosome 10.

    Directory of Open Access Journals (Sweden)

    Karl-F Bergeron

    2015-03-01

    Full Text Available Neural crest cells (NCC are a transient migratory cell population that generates diverse cell types such as neurons and glia of the enteric nervous system (ENS. Via an insertional mutation screen for loci affecting NCC development in mice, we identified one line-named TashT-that displays a partially penetrant aganglionic megacolon phenotype in a strong male-biased manner. Interestingly, this phenotype is highly reminiscent of human Hirschsprung's disease, a neurocristopathy with a still unexplained male sex bias. In contrast to the megacolon phenotype, colonic aganglionosis is almost fully penetrant in homozygous TashT animals. The sex bias in megacolon expressivity can be explained by the fact that the male ENS ends, on average, around a "tipping point" of minimal colonic ganglionosis while the female ENS ends, on average, just beyond it. Detailed analysis of embryonic intestines revealed that aganglionosis in homozygous TashT animals is due to slower migration of enteric NCC. The TashT insertional mutation is localized in a gene desert containing multiple highly conserved elements that exhibit repressive activity in reporter assays. RNAseq analyses and 3C assays revealed that the TashT insertion results, at least in part, in NCC-specific relief of repression of the uncharacterized gene Fam162b; an outcome independently confirmed via transient transgenesis. The transcriptional signature of enteric NCC from homozygous TashT embryos is also characterized by the deregulation of genes encoding members of the most important signaling pathways for ENS formation-Gdnf/Ret and Edn3/Ednrb-and, intriguingly, the downregulation of specific subsets of X-linked genes. In conclusion, this study not only allowed the identification of Fam162b coding and regulatory sequences as novel candidate loci for Hirschsprung's disease but also provides important new insights into its male sex bias.

  4. Construction and characterization of human chromosome 2-specific cosmid, fosmid, and PAC clone libraries

    Energy Technology Data Exchange (ETDEWEB)

    Gingrich, J.C.; Boehrer, D.M.; Garnes, J.A. [Lawrence Livermore National Lab., CA (United States)] [and others

    1996-02-15

    This article discusses the construction and characterization of three human chromosome 2-specific clone libraries. A chromosome 2-specific PAC library was also constructed from a hybrid cell line. The chromosome 2 coverage of each of the three libraries was further determined by PCR screening clone pools with 82 chromosome 2-specific STSs. 47 refs., 3 figs., 1 tab.

  5. Undetected sex chromosome aneuploidy by chromosomal microarray.

    Science.gov (United States)

    Markus-Bustani, Keren; Yaron, Yuval; Goldstein, Myriam; Orr-Urtreger, Avi; Ben-Shachar, Shay

    2012-11-01

    We report on a case of a female fetus found to be mosaic for Turner syndrome (45,X) and trisomy X (47,XXX). Chromosomal microarray analysis (CMA) failed to detect the aneuploidy because of a normal average dosage of the X chromosome. This case represents an unusual instance in which CMA may not detect chromosomal aberrations. Such a possibility should be taken into consideration in similar cases where CMA is used in a clinical setting.

  6. Allocation of the S-genome chromosomes of Aegilops variabilis Eig. carrying powdery mildew resistance in triticale (× Triticosecale Wittmack).

    Science.gov (United States)

    Kwiatek, M; Belter, J; Majka, M; Wiśniewska, H

    2016-03-01

    It has been hypothesized that the powdery mildew adult plant resistance (APR) controlled by the Pm13 gene in Aegilops longissima Schweinf. & Muschl. (S(l)S(l)) has been evolutionary transferred to Aegilops variabilis Eig. (UUSS). The molecular marker analysis and the visual evaluation of powdery mildew symptoms in Ae. variabilis and the Ae. variabilis × Secale cereale amphiploid forms (2n = 6x = 42, UUSSRR) showed the presence of product that corresponded to Pm13 marker and the lower infection level compared to susceptible model, respectively. This study also describes the transfer of Ae. variabilis Eig. (2n = 4x = 28, U(v)U(v)S(v)S(v)) chromosomes, carrying powdery mildew resistance, into triticale (× Triticosecale Wittm., 2n = 6x = 42, AABBRR) using Ae. variabilis × S. cereale amphiploid forms. The individual chromosomes of Ae. variabilis, triticale 'Lamberto' and hybrids were characterized by genomic and fluorescence in situ hybridization (GISH/FISH). The chromosome configurations of obtained hybrid forms were studied at first metaphase of meiosis of pollen mother cells (PMCs) using GISH. The statistical analysis showed that the way of S-genome chromosome pairing and transmission to subsequent hybrid generations was diploid-like and had no influence on chromosome pairing of triticale chromosomes. The cytogenetic study of hybrid forms were supported by the marker-assisted selection using Pm13 marker and visual evaluation of natural infection by Blumeria graminis, that allowed to select the addition or substitution lines of hybrids carrying chromosome 3S(v) which were tolerant to the powdery mildew infection.

  7. 黄瓜染色体片段导入系的构建与遗传评价%Construction and genetic evaluation of chromosome segment introgression lines in cucumber

    Institute of Scientific and Technical Information of China (English)

    史建磊; 娄群峰; 钱春桃; 万红建; 周晓慧; 陈劲枫

    2011-01-01

    The cultivated cucumber( Cucumis sativus L. ,2n = 14) Beijingjieton with comprehensive good traits and precious rare wild sour cucumber( Cucumis hystrix Chakr. ,2n =24)carrying a variety of resistance traits were used as receptor parent and donor parent respectively in the present study. Chromosome segment iutrogression lines(CSILs) were developed on the basis of interspeeific allotetraploid by multiple generational backcrossing and selfing, combined with SSR marker-assisted selection (MAS), with the genetic background of Beijingjietou. By evaluating of the number, distribution, segment size and coverage rate, it showed that the 38 donor segments of CSILs existed unevenly in the seven chromosomes. Their lengths were between 1.1 -14.9 cM, the average length was 5.3 cM, the total length was 201.9 cM and the coverage rate in the cucumber genome was 23.5%.%以综合性状优良的栽培黄瓜(Cucumis sativus L.,2n=14)北京截头为受休亲本,以携带有多种抗性性状的黄瓜珍稀野牛种酸黄瓜(Cucumis hystrix Chakr.,2n=24)为供体亲本,在本实验室前期获得种间杂交异源叫倍体的基础上,通过多代回交和自交,结合SSR标记辅助选择构建了以北京截头为遗传背景的黄瓜野生种染色体片段导入系,并对其导入片段的数日、分布、大小和覆盖率等进行了评价.结果表明:该导入系群体携带的38个供体片段不均匀地分布于黄瓜7条染色体上,其长度介于1.1~14.9 cM,平均长度为5.3 cM,总长度为201.9 cM,在黄瓜基因组上的覆盖率为23.5%.

  8. First evaluation of drug-resistant Mycobacterium tuberculosis clinical isolates from Congo revealed misdetection of fluoroquinolone resistance by line probe assay due to a double substitution T80A-A90G in GyrA.

    Directory of Open Access Journals (Sweden)

    Alexandra Aubry

    Full Text Available BACKGROUND: Tuberculosis (TB is one of the major public health problems in Congo. However, data concerning Mycobacterium tuberculosis drug resistance are lacking because of the insufficient processing capacity. So, the aim of this study was to investigate for the first time the resistance patterns and the strain lineages of a sample of M. tuberculosis complex (MTBC isolates collected in the two main cities of Congo. METHODS: Over a 9-day period, 114 smear-positive sputa isolated from 114 patients attending centers for the diagnosis and treatment of TB in Brazzaville and Pointe Noire were collected for culture and drug susceptibility testing (DST. Detection of mutations conferring drug resistance was performed by using line probe assays (GenoType MTBDRplus and MTBDRsl and DNA sequencing. Strain lineages were determined by MIRU-VNTR genotyping. RESULTS: Of the 114 sputa, 46 were culture positive for MTBC. Twenty-one (46% were resistant to one or more first-line antiTB drugs. Of these, 15 (71% were multidrug resistant (MDR. The most prevalent mutations involved in rifampin and isoniazid resistance, D516V (60% in rpoB and S315T (87% in katG respectively, were well detected by MTBDRplus assay. All the 15 MDR strains were susceptible to fluoroquinolone and injectable second-line drug. No mutation was detected in the rrs locus involved in resistance to amikacin and capreomycin by both the MTBDRsl assay and DNA sequencing. By contrast, 9 MDR strains belonging to the same cluster related to T-family were identified as being falsely resistant to fluoroquinolone by the MTBDRsl assay due to the presence of a double substitution T80A-A90G in GyrA. CONCLUSIONS: Taken together, these data revealed a possible spread of a particular MDR clone in Congo, misidentified as fluoroquinolone resistant by MTBDRsl assay. Thus, this test cannot replace gold-standard culture method and should be interpreted carefully in view of the patient's native land.

  9. [Y chromosome structural abnormalities and Turner's syndrome].

    Science.gov (United States)

    Ravel, C; Siffroi, J-P

    2009-06-01

    Although specifically male, the human Y chromosome may be observed in female karyotypes, mostly in women with Turner syndrome stigmata. In women with isolated gonadal dysgenesis but otherwise normal stature, the testis determining factor or SRY gene may have been removed from the Y chromosome or may be mutated. In other women with Turner syndrome, the karyotype is usually abnormal and shows a frequent 45,X/46,XY mosaicism. In these cases, the phenotype depends on the ratio between Y positive and 45,X cell lines in the body. When in mosaicism, Y chromosomes are likely to carry structural abnormalities which explain mitotic instability, such as the existence of two centromeres. Dicentric Y isochromosomes for the short arm (idic[Yp]) or ring Y chromosomes (r[Y]) are the most frequent abnormal Y chromosomes found in infertile patients and in Turner syndrome in mosaic with 45,X cells. Although monocentric, deleted Y chromosomes for the long arm and those carrying microdeletions in the AZF region are also instable and are frequently associated with a 45,X cell line. Management of infertile patients carrying such abnormal Y chromosomes must take into account the risk and the consequences of a mosaicism in the offspring.

  10. Chromosome Disorder Outreach

    Science.gov (United States)

    ... BLOG Join Us Donate You are not alone. Chromosome Disorder Outreach, Inc. is a non-profit organization, ... Support For all those diagnosed with any rare chromosome disorder. Since 1992, CDO has supported the parents ...

  11. CHROMOSOME LOCATION OF GENETIC FACTORS DETERMINIG PHYSIOLOGICAL AND BIOCHEMICAL PROCESSES ASSOCIATED WITH DROUGHT TOLERANCE IN WHEAT TRITICUM AESTIVUM L.

    Directory of Open Access Journals (Sweden)

    Osipova S.

    2012-08-01

    Full Text Available Drought tolerance is characterized as the most recalcitrant trait to improve for its complexity and considered target for genomic-assisted improvement. A profitable genetic strategy lies in the discovery and exploitation of quantitative trait loci (QTL involved in determining tolerance to water deficit at the cellular level. Enzymes of the antioxidant system participating in detoxification of reactive oxygen species accumulating under stress are the essential component of the common protective systems in cell. The same is lipoxygenase – a key enzyme of jasmonate-dependent signaling pathway initiating the development of adaptive programs in cell. Understanding of the genetic basis of wheat drought tolerance as a polygenic trait and identification of the QTL is facilitated by the availability of a number of sets of inter-varietal single chromosome substitution lines (ISCSLs in bread wheat Triticum aestivum L. Two sets of bread wheat ISCSLs were used in this study. In the first set, 'Saratovskaya' 29 (S29 / 'Janetzkis Probat' (JP, the recipient was a drought tolerant cultivar and the donor of individual pairs of homologous chromosomes was a sensitive one. In the second set, 'Chinese Spring' (CS / 'Synthetic 6x' (Syn 6x, the donor of separate chromosomes was a synthetic hexaploid wheat (T. dicoccoides X Ae. tauschii. In the set S29/JP the chromosomes of the second homoeological group and 4D chromosome were found to be critical for drought tolerance. A decrease of tolerance correlated with decreasing of antioxidant enzymes cumulative activity in leaves. In the set CS/Syn, chromosomes 4B and 4D were found to be critical for drought tolerance. The levels of LOX activity in leaves of both sets differently correlated with grain productivity but influenced positively on retaining a grain size under drought. Besides the structural genes for LOX biosynthesis situated on chromosomes of 4 and 5 homoeological groups, in both sets, the genetic factors on

  12. Human endogenous retrovirus family HERV-K(HML-2) RNA transcripts are selectively packaged into retroviral particles produced by the human germ cell tumor line Tera-1 and originate mainly from a provirus on chromosome 22q11.21.

    Science.gov (United States)

    Ruprecht, Klemens; Ferreira, Humberto; Flockerzi, Aline; Wahl, Silke; Sauter, Marlies; Mayer, Jens; Mueller-Lantzsch, Nikolaus

    2008-10-01

    The human germ cell tumor line Tera-1 produces retroviral particles which are encoded by the human endogenous retrovirus family HERV-K(HML-2). We show here, by quantitative reverse transcriptase PCR, that HML-2 gag and env RNA transcripts are selectively packaged into Tera-1 retroviral particles, whereas RNAs from cellular housekeeping genes and from other HERV families (HERV-H and HERV-W) are nonselectively copackaged. Assignment of cloned HML-2 gag and env cDNAs from Tera-1 retroviral particles to individual HML-2 loci in the human genome demonstrated that HML-2 RNA transcripts packaged into Tera-1 retroviral particles originate almost exclusively from an HML-2 provirus on chromosome 22q11.21. Based on relative cloning frequencies, this provirus was the most active among a total of eight transcribed HML-2 loci identified in Tera-1 cells. These data suggest that at least one HML-2 element, that is, the HML-2 provirus on 22q11.21, has retained the capacity for packaging RNA into HML-2-encoded retroviral particles. Given its elevated transcriptional activity and the presence of a full-length Gag open reading frame, the 22q11.21 HML-2 provirus may also significantly contribute to Gag protein and thus particle production in Tera-1 cells. Our findings provide important clues to the generation and biological properties of HML-2-encoded particles. In addition, copackaging of non-HML-2 HERV transcripts in HML-2-encoded particles should inform the debate about endogenous retroviral particles putatively encoded by non-HML-2 HERV families that have previously been described for other human diseases, such as multiple sclerosis.

  13. Chromosome painting in plants.

    NARCIS (Netherlands)

    Schubert, I.; Fransz, P.F.; Fuchs, J.; Jong, de J.H.

    2001-01-01

    The current 'state-of-art' as to chromosome painting in plants is reviewed. We define different situations described as painting so far: i) Genomic in situ hybridisation (GISH) with total genomic DNA to distinguish alien chromosomes on the basis of divergent dispersed repeats, ii) 'Chromosomal in si

  14. ZEBRAFISH CHROMOSOME-BANDING

    NARCIS (Netherlands)

    PIJNACKER, LP; FERWERDA, MA

    1995-01-01

    Banding techniques were carried out on metaphase chromosomes of zebrafish (Danio rerio) embryos. The karyotypes with the longest chromosomes consist of 12 metacentrics, 26 submetacentrics, and 12 subtelocentrics (2n = 50). All centromeres are C-band positive. Eight chromosomes have a pericentric C-b

  15. 40 CFR 721.8780 - Substituted pyridine azo substituted phenyl.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted pyridine azo substituted... Specific Chemical Substances § 721.8780 Substituted pyridine azo substituted phenyl. (a) Chemical substance... substituted pyridine azo substituted phenyl (PMNs P-96-767 and P-96-773) are subject to reporting under...

  16. Construction and characterization of genomic libraries from specific human chromosomes.

    Science.gov (United States)

    Krumlauf, R; Jeanpierre, M; Young, B D

    1982-05-01

    Highly purified fractions of human chromosomes 21 and 22 were isolated from a suspension of metaphase chromosomes stained with ethidium bromide by using a fluorescence-activated cell sorter (FACS II). Two recombinant DNA libraries, representing chromosomes 21 and 22, were constructed by complete digestion of DNA from these fractions with EcoRI and insertion into the vector lambda gtWES lambda B. Twenty clones selected at random from the chromosome 22 library hybridized to EcoRI-digested human DNA, and five of these clones hybridized to single bands identical in size to the phage inserts. These five single-copy sequences and a clone coding for an 8S RNA isolated by screening the chromosome 22 library for expressed sequences were characterized in detail. Hybridization of all six clones to a panel of sorted chromosomes and hybrid cell lines confirmed the assignment of the sequences to chromosome 22. The sequences were localized to regions of chromosome 22 by hybridization to translocated chromosomes sorted from a cell line having a balanced translocation t(17;22)(p13;q11) and to hybrid cell lines containing the various portions of another translocation t(X;22)(q13;q112). Five clones reside on the long arm of chromosome 22 between q112 and pter, while one clone and an 18S rRNA gene isolated from the chromosome 22 library reside pter and g112. The construction of chromosome-specific libraries by this method has the advantage of being direct and applicable to nearly all human chromosomes and will be important in molecular analysis of human genetic diseases.

  17. Chromosomal Location of Traits Associated with Wheat Seedling Water and Phosphorus Use Efficiency under Different Water and Phosphorus Stresses

    Directory of Open Access Journals (Sweden)

    Wei-Yi Song

    2009-09-01

    Full Text Available The objective of this study was to locate chromosomes for improving water and phosphorus-deficiency tolerance of wheat at the seedling stage. A set of Chinese Spring- Egyptian Red wheat substitution lines and their parent Chinese Spring (recipient and Egyptian Red (donor cultivars were measured to determine the chromosomal locations of genes controlling water use efficiency (WUE and phosphorus use efficiency (PUE under different water and phosphorus conditions. The results underlined that chromosomes 1A, 7A, 7B, and 3A showed higher leaf water use efficiency (WUEl = Pn/Tr; Pn = photosynthetic rate; Tr = transpiration rate under W-P (Hoagland solution with1/2P, -W-P (Hoagland solution with 1/2P and 10% PEG. Chromosomes 7A, 3D, 2B, 3B, and 4B may carry genes for positive effects on individual plant water use efficiency (WUEp = biomass/TWC; TWC = total water consumption under WP (Hoagland solution, W-P and -W-P treatment. Chromosomes 7A and 7D carry genes for PUE enhancement under WP, -WP (Hoagland solution with 10% PEG and W-P treatment. Chromosome 7A possibly has genes for controlling WUE and PUE simultaneously, which indicates that WUE and PUE may share the same genetic background. Phenotypic and genetic analysis of the investigated traits showed that photosynthetic rate (Pn and transpiration rate (Tr, Tr and WUEl showed significant positive and negative correlations under WP, W-P, -WP and -W-P, W-P, -WP treatments, respectively. Dry mass (DM, WUEP, PUT (phosphorus uptake all showed significant positive correlation under WP, W-P and -WP treatment. PUE and phosphorus uptake (PUT = P uptake per plant showed significant negative correlation under the four treatments. The results might provide useful information for improving WUE and PUE in wheat genetics.

  18. Chromosomal instability in meningiomas.

    Science.gov (United States)

    van Tilborg, Angela A G; Al Allak, Bushra; Velthuizen, Sandra C J M; de Vries, Annie; Kros, Johan M; Avezaat, Cees J J; de Klein, Annelies; Beverloo, H Berna; Zwarthoff, Ellen C

    2005-04-01

    Approximately 60% of sporadic meningiomas are caused by inactivation of the NF2 tumor suppressor gene on chromosome 22. No causative gene is known for the remaining 40%. Cytogenetic analysis shows that meningiomas caused by inactivation of the NF2 gene can be divided into tumors that show monosomy 22 as the sole abnormality and tumors with a more complex karyotype. Meningiomas not caused by the NF2 gene usually have a diploid karyotype. Here we report that, besides the clonal chromosomal aberrations, the chromosome numbers in many meningiomas varied from one metaphase spread to the other, a feature that is indicative of chromosomal instability. Unexpectedly and regardless of genotype, a subgroup of tumors was observed with an average number of 44.9 chromosomes and little variation in the number of chromosomes per metaphase spread. In addition, a second subgroup was recognized with a hyperdiploid number of chromosomes (average 48.5) and considerable variation in numbers per metaphase. However, this numerical instability resulted in a clonal karyotype with chromosomal gains and losses in addition to loss of chromosome 22 only in meningiomas caused by inactivation of the NF2 gene. In cultured cells of all tumor groups, bi- and multinucleated cells were seen, as well as anaphase bridges, residual chromatid strings, multiple spindle poles, and unseparated chromatids, suggesting defects in the mitotic apparatus or kinetochore. Thus, we conclude that even a benign and slow-growing tumor like a meningioma displays chromosomal instability.

  19. A grandparent-influenced locus for alcohol preference on mouse chromosome 2

    NARCIS (Netherlands)

    Lesscher, Heidi M B; Kas, Martien J H; van der Elst, Stefan; van Lith, Hein A; Vanderschuren, Louk J M J

    2009-01-01

    OBJECTIVE: Loci on mouse chromosome 2 have previously been associated with ethanol consumption. Here, we used a limited access choice paradigm in which mice consume large quantities of ethanol (2-3 g/kg/2 h) with a high preference (>80%). In addition, mouse chromosome substitution strains were used

  20. Analysis of plant meiotic chromosomes by chromosome painting.

    Science.gov (United States)

    Lysak, Martin A; Mandáková, Terezie

    2013-01-01

    Chromosome painting (CP) refers to visualization of large chromosome regions, entire chromosome arms, or entire chromosomes via fluorescence in situ hybridization (FISH). For CP in plants, contigs of chromosome-specific bacterial artificial chromosomes (BAC) from the target species or from a closely related species (comparative chromosome painting, CCP) are typically applied as painting probes. Extended pachytene chromosomes provide the highest resolution of CP in plants. CP enables identification and tracing of particular chromosome regions and/or entire chromosomes throughout all meiotic stages as well as corresponding chromosome territories in premeiotic interphase nuclei. Meiotic pairing and structural chromosome rearrangements (typically inversions and translocations) can be identified by CP. Here, we describe step-by-step protocols of CP and CCP in plant species including chromosome preparation, BAC DNA labeling, and multicolor FISH.

  1. Meiotic chromosomes and stages of sex chromosome evolution in fish: zebrafish, platyfish and guppy.

    Science.gov (United States)

    Traut, W; Winking, H

    2001-01-01

    We describe SC complements and results from comparative genomic hybridization (CGH) on mitotic and meiotic chromosomes of the zebrafish Danio rerio, the platyfish Xiphophorus maculatus and the guppy Poecilia reticulata. The three fish species represent basic steps of sex chromosome differentiation: (1) the zebrafish with an all-autosome karyotype; (2) the platyfish with genetically defined sex chromosomes but no differentiation between X and Y visible in the SC or with CGH in meiotic and mitotic chromosomes; (3) the guppy with genetically and cytogenetically differentiated sex chromosomes. The acrocentric Y chromosomes of the guppy consists of a proximal homologous and a distal differential segment. The proximal segment pairs in early pachytene with the respective X chromosome segment. The differential segment is unpaired in early pachytene but synapses later in an 'adjustment' or 'equalization' process. The segment includes a postulated sex determining region and a conspicuous variable heterochromatic region whose structure depends on the particular Y chromosome line. CGH differentiates a large block of predominantly male-specific repetitive DNA and a block of common repetitive DNA in that region.

  2. Effects of hepatitis B virus infection on human sperm chromosomes

    Institute of Scientific and Technical Information of China (English)

    Jian-Min Huang; Tian-Hua Huang; Huan-Ying Qiu; Xiao-Wu Fang; Tian-Gang Zhuang; Hong-Xi Liu; Yong-Hua Wang; Li-Zhi Deng; Jie-Wen Qiu

    2003-01-01

    /or induction chromosome aberrations, as well as the possibility of vertical transmission of HBV via the germ line to the next generation.

  3. Chromosomal Instability Confers Intrinsic Multidrug Resistance

    DEFF Research Database (Denmark)

    Lee, Alvin J. X.; Endesfelder, David; Rowan, Andrew J.

    2011-01-01

    their diploid parental cells only with increasing chromosomal heterogeneity and isogenic cell line models of CIN+ displayed multidrug resistance relative to their CIN- parental cancer cell line derivatives. In a meta-analysis of CRC outcome following cytotoxic treatment, CIN+ predicted worse progression......-free or disease-free survival relative to patients with CIN- disease. Our results suggest that stratifying tumor responses according to CIN status should be considered within the context of clinical trials to minimize the confounding effects of tumor CIN status on drug sensitivity. Cancer Res; 71(5); 1858-70. (c......Aneuploidy is associated with poor prognosis in solid tumors. Spontaneous chromosome missegregation events in aneuploid cells promote chromosomal instability (CIN) that may contribute to the acquisition of multidrug resistance in vitro and heighten risk for tumor relapse in animal models...

  4. Positioning of human chromosomes in murine cell hybrids according to synteny.

    Science.gov (United States)

    Meaburn, Karen J; Newbold, Robert F; Bridger, Joanna M

    2008-12-01

    Chromosomes occupy non-random spatial positions in interphase nuclei. It remains unclear what orchestrates this high level of organisation. To determine how the nuclear environment influences the spatial positioning of chromosomes, we utilised a panel of stable mouse hybrid cell lines carrying a single, intact human chromosome. Eleven of 22 human chromosomes revealed an alternative location in hybrid nuclei compared to that of human fibroblasts, with the majority becoming more internally localised. Human chromosomes in mouse nuclei position according to neither their gene density nor size, but rather the position of human chromosomes in hybrid nuclei appears to mimic that of syntenic mouse chromosomes. These results suggest that chromosomes adopt the behaviour of their host species chromosomes and that the nuclear environment is an important determinant of the interphase positioning of chromosomes.

  5. Isolation and characterization of DNA probes for human chromosome 21.

    Science.gov (United States)

    Watkins, P C

    1990-01-01

    A coordinated effort to map and sequence the human genome has recently become a national priority. Chromosome 21, the smallest human chromosome accounting for less than 2% of the human genome, is an attractive model system for developing and evaluating genome mapping technology. Several strategies are currently being explored including the development of chromosome 21 libraries from somatic cell hybrids as reported here, the cloning of chromosome 21 in yeast artificial chromosomes (McCormick et al., 1989b), and the construction of chromosome 21 libraries using chromosome flow-sorting techniques (Fuscoe et al., 1989). This report describes the approaches used to identify DNA probes that are useful for mapping chromosome 21. Probes were successfully isolated from both phage and cosmid libraries made from two somatic cell hybrids that contain human chromosome 21 as the only human chromosome. The 15 cosmid clones from the WA17 library, reduced to cloned DNA sequences of an average size of 3 kb, total 525 kb of DNA which is approximately 1% of chromosome 21. From these clones, a set of polymorphic DNA markers that span the length of the long arm of chromosome 21 has been generated. All of the probes thus far analyzed from the WA17 libraries have been mapped to chromosome 21 both by physical and genetic mapping methods. It is therefore likely that the WA17 hybrid cell line contains human chromosome 21 as the only human component, in agreement with cytogenetic observation. The 153E7b cosmid libraries will provide an alternative source of cloned chromosome 21 DNA. Library screening techniques can be employed to obtain cloned DNA sequences from the same genetic loci of the two different chromosome 21s. Comparative analysis will allow direct estimation of DNA sequence variation for different regions of chromosome 21. Mapped DNA probes make possible the molecular analysis of chromosome 21 at a level of resolution not achievable by classical cytogenetic techniques (Graw et al

  6. Medicineringsfejl ved generisk substitution

    DEFF Research Database (Denmark)

    Rölfing, Jan

    2012-01-01

    Generic substitution is a major cause of medical mistakes in the general population. Danish legislation obligates pharmacies to substitute prescribed medicine with the cheapest equivalent formulation, despite variations in product name, packaging, shape and colour. Consequently, medical mistakes ...... occur. Scientific evidence on the consequences of generic substitution is sparse. Call upon fellow health workers to report medical mistakes to the national entities and scientific peers, in order to increase awareness and scientific evidence about the problem....

  7. The Precarious Prokaryotic Chromosome

    OpenAIRE

    Kuzminov, Andrei

    2014-01-01

    Evolutionary selection for optimal genome preservation, replication, and expression should yield similar chromosome organizations in any type of cells. And yet, the chromosome organization is surprisingly different between eukaryotes and prokaryotes. The nuclear versus cytoplasmic accommodation of genetic material accounts for the distinct eukaryotic and prokaryotic modes of genome evolution, but it falls short of explaining the differences in the chromosome organization. I propose that the t...

  8. Mechanisms for chromosome segregation.

    Science.gov (United States)

    Bouet, Jean-Yves; Stouf, Mathieu; Lebailly, Elise; Cornet, François

    2014-12-01

    Bacteria face the problem of segregating their gigantic chromosomes without a segregation period restricted in time and space, as Eukaryotes do. Segregation thus involves multiple activities, general or specific of a chromosome region and differentially controlled. Recent advances show that these various mechanisms conform to a “pair and release” rule, which appears as a general rule in DNA segregation. We describe the latest advances in segregation of bacterial chromosomes with emphasis on the different pair and release mechanisms.

  9. Cyclotomic Aperiodic Substitution Tilings

    Directory of Open Access Journals (Sweden)

    Stefan Pautze

    2017-01-01

    Full Text Available The class of Cyclotomic Aperiodic Substitution Tilings (CASTs is introduced. Its vertices are supported on the 2 n -th cyclotomic field. It covers a wide range of known aperiodic substitution tilings of the plane with finite rotations. Substitution matrices and minimal inflation multipliers of CASTs are discussed as well as practical use cases to identify specimen with individual dihedral symmetry D n or D 2 n , i.e., the tiling contains an infinite number of patches of any size with dihedral symmetry D n or D 2 n only by iteration of substitution rules on a single tile.

  10. Bacterial chromosome segregation.

    Science.gov (United States)

    Possoz, Christophe; Junier, Ivan; Espeli, Olivier

    2012-01-01

    Dividing cells have mechanisms to ensure that their genomes are faithfully segregated into daughter cells. In bacteria, the description of these mechanisms has been considerably improved in the recent years. This review focuses on the different aspects of bacterial chromosome segregation that can be understood thanks to the studies performed with model organisms: Escherichia coli, Bacillus subtilis, Caulobacter crescentus and Vibrio cholerae. We describe the global positionning of the nucleoid in the cell and the specific localization and dynamics of different chromosomal loci, kinetic and biophysic aspects of chromosome segregation are presented. Finally, a presentation of the key proteins involved in the chromosome segregation is made.

  11. Chromosome oscillations in mitosis

    Science.gov (United States)

    Campas, Otger

    2008-03-01

    Successful cell division necessitates a tight regulation of chromosome movement via the activity of molecular motors. Many of the key players at the origin of the forces generating the motion have been identified, but their spatial and temporal organization remains elusive. In animal cells, chromosomes periodically switch between phases of movement towards and away from the pole. This characteristic oscillatory behaviour cannot be explained by the current models of chromosome positioning and congression. We perform a self-contained theoretical analysis in which the motion of mono-oriented chromosomes results from the competition between the activity of the kinetochore and chromokinesin motors on the chromosome arms. Our analysis, consistent with the available experimental data, proposes that the interplay between the aster-like morphology of the spindle and the collective kinetics of molecular motors is at the origin of chromosome oscillations, positioning and congression. It provides a natural explanation for the so-called chromosome directional instability and for the mechanism by which chromosomes sense their position in space. In addition, we estimate the in vivo velocity of chromokinesins at vanishing load and propose new experiments to assess the mechanism at the origin of chromosome movement in cell division.

  12. Fetal chromosome analysis: screening for chromosome disease?

    DEFF Research Database (Denmark)

    Philip, J; Tabor, Ann; Bang, J

    1983-01-01

    The aim of the study was to investigate the rationale of the current indications for fetal chromosome analysis. 5372 women had 5423 amniocentesis performed, this group constituting a consecutive sample at the chromosome laboratory, Rigshospitalet, Copenhagen from March 1973 to September 1980 (Group...... to women having amniocentesis, although considered not to have any increased risk of fetal chromosome abnormality (1390 pregnancies, group B). They were also compared with 750 consecutive pregnancies in women 25-34 years of age, in whom all heritable diseases were excluded (group C). The risk of unbalanced...... with women without elevated risk. Spontaneous abortion rate and prematurity rate did not differ from rates expected without amniocentesis. It is concluded that current indications may be characterized as a mixture of evident high risk factors and factors with only a minor influence on risk. Indications...

  13. XYY chromosome anomaly and schizophrenia.

    Science.gov (United States)

    Rajagopalan, M; MacBeth, R; Varma, S L

    1998-02-07

    Sex chromosome anomalies have been associated with psychoses, and most of the evidence is linked to the presence of an additional X chromosome. We report a patient with XYY chromosome anomaly who developed schizophrenia.

  14. Patterns of nucleotide substitution in angiosperm cpDNA trnL (UAA)-F(GAA) regions

    NARCIS (Netherlands)

    Bakker, F.T.; Culham, A.; Gomez-Martinez, R.; Carvalho, J.; Compton, J.; Dawtrey, R.; Gibby, M.

    2000-01-01

    Patterns of substitution in chloroplast encoded trnL-F regions were compared between species of Actaea (Ranunculales), Digitalis (Scrophulariales), Drosera (Caryophyllales), Panicoideae (Poales), the small chromosome species clade of Pelargonium (Geraniales), each representing a different order of f

  15. Dissection of QTLs for Yield Traits Using Near Isogenic Lines Derived from Residual Heterozygous Lines in Rice

    Institute of Scientific and Technical Information of China (English)

    Du Jing-hong; FAN Ye-yang; WANG Lei; ZHUANG Jie-yun

    2008-01-01

    Three residual heterozygous lines (RHLs) carrying heterozygous segments in the intervals RM587-RM225, RM204-RM6119 and RM6119-RM402 on the short arm of rice chromosome 6, respectively, were selected from a rice population derived from an RHL for the interval RM587-RM402. Ten maternal homozygotes, 10 paternal homozygotes and 20 heterozygotes were selected from each of the F2 populations derived from the three RHLs. The three sets of near isogenic lines (NILs) were grown to detect the grain yield per plant, number of panicles per plant, number of filled grains per panicle and 1000-grain weight. With analysis on the phenotypic differences among the three genotype groups in each NIL set and those among overlapping chromosome segment substitution lines, three QTLs for number of filled grains per panicle and two QTLs for grain yield per plant were resolved. They were located in the intervals ranging from 0.66 Mb to 2.49 Mb. The additive effect was higher than the dominance effect at each locus. The allele for increasing the trait value was derived from the paternal parent at qNFGP6-1, and from the maternal alleles at other QTLs. Based on the present study, an approach for constructing new genetic resource to facilitate fine mapping of QTLs in rice was proposed.

  16. Sex chromosome mosaicism in males carrying Y chromosome long arm deletions.

    Science.gov (United States)

    Siffroi, J P; Le Bourhis, C; Krausz, C; Barbaux, S; Quintana-Murci, L; Kanafani, S; Rouba, H; Bujan, L; Bourrouillou, G; Seifer, I; Boucher, D; Fellous, M; McElreavey, K; Dadoune, J P

    2000-12-01

    Microdeletions of the long arm of the Y chromosome (Yq) are a common cause of male infertility. Since large structural rearrangements of the Y chromosome are commonly associated with a 45,XO/46,XY chromosomal mosaicism, we studied whether submicroscopic Yq deletions could also be associated with the development of 45,XO cell lines. We studied blood samples from 14 infertile men carrying a Yq microdeletion as revealed by polymerase chain reaction (PCR). Patients were divided into two groups: group 1 (n = 6), in which karyotype analysis demonstrated a 45,X/46,XY mosaicism, and group 2 (n = 8) with apparently a normal 46,XY karyotype. 45,XO cells were identified by fluorescence in-situ hybridization (FISH) using X and Y centromeric probes. Lymphocytes from 11 fertile men were studied as controls. In addition, sperm cells were studied in three oligozoospermic patients in group 2. Our results showed that large and submicroscopic Yq deletions were associated with significantly increased percentages of 45,XO cells in lymphocytes and of sperm cells nullisomic for gonosomes, especially for the Y chromosome. Moreover, two isodicentric Y chromosomes, classified as normal by cytogenetic methods, were detected. Therefore, Yq microdeletions may be associated with Y chromosomal instability leading to the formation of 45,XO cell lines.

  17. Prenatal Diagnosis of a Fetus with Congenital Heart Defect and Ring Chromosome 14

    Directory of Open Access Journals (Sweden)

    Javier Sánchez

    2012-01-01

    Full Text Available Monosomy of chromosome 14 has been reported in only a few prenatal cases. Generally, this monosomy is associated with a mosaicism of ring chromosome 14. Ring chromosome 14 is a rare cytogenetic entity with clinical characteristics that include growth retardation, facial dysmorphia, hypotonia, seizures, and retinitis pigmentosa. Given that the majority of symptoms appear postnatally, few cases have been reported of prenatal diagnosis of mosaicism monosomy/ring chromosome 14. We describe the prenatal diagnosis of a case of chromosomal mosaicism, a cell line with ring chromosome 14, r(14, and a second cell line with monosomy 14, in a fetus with aortic coarctation and chamber asymmetry. This is the first case of a prenatal diagnosis associating mosaicism with ring chromosome 14, monosomy 14, and fetal cardiopathy. We identified the exact breakpoint in ring chromosome 14 in IGH locus, which may provide further insight into the mode of ring formation as well as prenatal findings.

  18. DNA Repair Defects and Chromosomal Aberrations

    Science.gov (United States)

    Hada, Megumi; George, K. A.; Huff, J. L.; Pluth, J. M.; Cucinotta, F. A.

    2009-01-01

    Yields of chromosome aberrations were assessed in cells deficient in DNA doublestrand break (DSB) repair, after exposure to acute or to low-dose-rate (0.018 Gy/hr) gamma rays or acute high LET iron nuclei. We studied several cell lines including fibroblasts deficient in ATM (ataxia telangiectasia mutated; product of the gene that is mutated in ataxia telangiectasia patients) or NBS (nibrin; product of the gene mutated in the Nijmegen breakage syndrome), and gliomablastoma cells that are proficient or lacking in DNA-dependent protein kinase (DNA-PK) activity. Chromosomes were analyzed using the fluorescence in situ hybridization (FISH) chromosome painting method in cells at the first division post irradiation, and chromosome aberrations were identified as either simple exchanges (translocations and dicentrics) or complex exchanges (involving >2 breaks in 2 or more chromosomes). Gamma irradiation induced greater yields of both simple and complex exchanges in the DSB repair-defective cells than in the normal cells. The quadratic dose-response terms for both simple and complex chromosome exchanges were significantly higher for the ATM- and NBS-deficient lines than for normal fibroblasts. However, in the NBS cells the linear dose-response term was significantly higher only for simple exchanges. The large increases in the quadratic dose-response terms in these repair-defective cell lines points the importance of the functions of ATM and NBS in chromatin modifications to facilitate correct DSB repair and minimize the formation of aberrations. The differences found between ATM- and NBS-deficient cells at low doses suggest that important questions should with regard to applying observations of radiation sensitivity at high dose to low-dose exposures. For aberrations induced by iron nuclei, regression models preferred purely linear dose responses for simple exchanges and quadratic dose responses for complex exchanges. Relative biological effectiveness (RBE) factors of all of

  19. The finished DNA sequence of human chromosome 12.

    Science.gov (United States)

    Scherer, Steven E; Muzny, Donna M; Buhay, Christian J; Chen, Rui; Cree, Andrew; Ding, Yan; Dugan-Rocha, Shannon; Gill, Rachel; Gunaratne, Preethi; Harris, R Alan; Hawes, Alicia C; Hernandez, Judith; Hodgson, Anne V; Hume, Jennifer; Jackson, Andrew; Khan, Ziad Mohid; Kovar-Smith, Christie; Lewis, Lora R; Lozado, Ryan J; Metzker, Michael L; Milosavljevic, Aleksandar; Miner, George R; Montgomery, Kate T; Morgan, Margaret B; Nazareth, Lynne V; Scott, Graham; Sodergren, Erica; Song, Xing-Zhi; Steffen, David; Lovering, Ruth C; Wheeler, David A; Worley, Kim C; Yuan, Yi; Zhang, Zhengdong; Adams, Charles Q; Ansari-Lari, M Ali; Ayele, Mulu; Brown, Mary J; Chen, Guan; Chen, Zhijian; Clerc-Blankenburg, Kerstin P; Davis, Clay; Delgado, Oliver; Dinh, Huyen H; Draper, Heather; Gonzalez-Garay, Manuel L; Havlak, Paul; Jackson, Laronda R; Jacob, Leni S; Kelly, Susan H; Li, Li; Li, Zhangwan; Liu, Jing; Liu, Wen; Lu, Jing; Maheshwari, Manjula; Nguyen, Bao-Viet; Okwuonu, Geoffrey O; Pasternak, Shiran; Perez, Lesette M; Plopper, Farah J H; Santibanez, Jireh; Shen, Hua; Tabor, Paul E; Verduzco, Daniel; Waldron, Lenee; Wang, Qiaoyan; Williams, Gabrielle A; Zhang, Jingkun; Zhou, Jianling; Allen, Carlana C; Amin, Anita G; Anyalebechi, Vivian; Bailey, Michael; Barbaria, Joseph A; Bimage, Kesha E; Bryant, Nathaniel P; Burch, Paula E; Burkett, Carrie E; Burrell, Kevin L; Calderon, Eliana; Cardenas, Veronica; Carter, Kelvin; Casias, Kristal; Cavazos, Iracema; Cavazos, Sandra R; Ceasar, Heather; Chacko, Joseph; Chan, Sheryl N; Chavez, Dean; Christopoulos, Constantine; Chu, Joseph; Cockrell, Raynard; Cox, Caroline D; Dang, Michelle; Dathorne, Stephanie R; David, Robert; Davis, Candi Mon'Et; Davy-Carroll, Latarsha; Deshazo, Denise R; Donlin, Jeremy E; D'Souza, Lisa; Eaves, Kristy A; Egan, Amy; Emery-Cohen, Alexandra J; Escotto, Michael; Flagg, Nicole; Forbes, Lisa D; Gabisi, Abdul M; Garza, Melissa; Hamilton, Cerissa; Henderson, Nicholas; Hernandez, Omar; Hines, Sandra; Hogues, Marilyn E; Huang, Mei; Idlebird, DeVincent G; Johnson, Rudy; Jolivet, Angela; Jones, Sally; Kagan, Ryan; King, Laquisha M; Leal, Belita; Lebow, Heather; Lee, Sandra; LeVan, Jaclyn M; Lewis, Lakeshia C; London, Pamela; Lorensuhewa, Lorna M; Loulseged, Hermela; Lovett, Demetria A; Lucier, Alice; Lucier, Raymond L; Ma, Jie; Madu, Renita C; Mapua, Patricia; Martindale, Ashley D; Martinez, Evangelina; Massey, Elizabeth; Mawhiney, Samantha; Meador, Michael G; Mendez, Sylvia; Mercado, Christian; Mercado, Iracema C; Merritt, Christina E; Miner, Zachary L; Minja, Emmanuel; Mitchell, Teresa; Mohabbat, Farida; Mohabbat, Khatera; Montgomery, Baize; Moore, Niki; Morris, Sidney; Munidasa, Mala; Ngo, Robin N; Nguyen, Ngoc B; Nickerson, Elizabeth; Nwaokelemeh, Ogechi O; Nwokenkwo, Stanley; Obregon, Melissa; Oguh, Maryann; Oragunye, Njideka; Oviedo, Rodolfo J; Parish, Bridgette J; Parker, David N; Parrish, Julia; Parks, Kenya L; Paul, Heidie A; Payton, Brett A; Perez, Agapito; Perrin, William; Pickens, Adam; Primus, Eltrick L; Pu, Ling-Ling; Puazo, Maria; Quiles, Miyo M; Quiroz, Juana B; Rabata, Dina; Reeves, Kacy; Ruiz, San Juana; Shao, Hongmei; Sisson, Ida; Sonaike, Titilola; Sorelle, Richard P; Sutton, Angelica E; Svatek, Amanda F; Svetz, Leah Anne; Tamerisa, Kavitha S; Taylor, Tineace R; Teague, Brian; Thomas, Nicole; Thorn, Rachel D; Trejos, Zulma Y; Trevino, Brenda K; Ukegbu, Ogechi N; Urban, Jeremy B; Vasquez, Lydia I; Vera, Virginia A; Villasana, Donna M; Wang, Ling; Ward-Moore, Stephanie; Warren, James T; Wei, Xuehong; White, Flower; Williamson, Angela L; Wleczyk, Regina; Wooden, Hailey S; Wooden, Steven H; Yen, Jennifer; Yoon, Lillienne; Yoon, Vivienne; Zorrilla, Sara E; Nelson, David; Kucherlapati, Raju; Weinstock, George; Gibbs, Richard A

    2006-03-16

    Human chromosome 12 contains more than 1,400 coding genes and 487 loci that have been directly implicated in human disease. The q arm of chromosome 12 contains one of the largest blocks of linkage disequilibrium found in the human genome. Here we present the finished sequence of human chromosome 12, which has been finished to high quality and spans approximately 132 megabases, representing approximately 4.5% of the human genome. Alignment of the human chromosome 12 sequence across vertebrates reveals the origin of individual segments in chicken, and a unique history of rearrangement through rodent and primate lineages. The rate of base substitutions in recent evolutionary history shows an overall slowing in hominids compared with primates and rodents.

  20. Karyotype variability in tropical maize sister inbred lines and hybrids compared with KYS standard line.

    Science.gov (United States)

    Mondin, Mateus; Santos-Serejo, Janay A; Bertäo, Mônica R; Laborda, Prianda; Pizzaia, Daniel; Aguiar-Perecin, Margarida L R

    2014-01-01

    Maize karyotype variability has been extensively investigated. The identification of maize somatic and pachytene chromosomes has improved with the development of fluorescence in situ hybridization (FISH) using tandemly repeated DNA sequences as probes. We identified the somatic chromosomes of sister inbred lines that were derived from a tropical flint maize population (Jac Duro [JD]), and hybrids between them, using FISH probes for the 180-bp knob repeat, centromeric satellite (CentC), centromeric satellite 4 (Cent4), subtelomeric clone 4-12-1, 5S ribosomal DNA and nucleolus organizing region DNA sequences. The observations were integrated with data based on C-banded mitotic metaphases and conventional analysis of pachytene chromosomes. Heterochromatic knobs visible at pachynema were coincident with C-bands and 180-bp FISH signals on somatic chromosomes, and most of them were large. Variation in the presence of some knobs was observed among lines. Small 180-bp knob signals were invariant on the short arms of chromosomes 1, 6, and 9. The subtelomeric 4-12-1 signal was also invariant and useful for identifying some chromosomes. The centromere location of chromosomes 2 and 4 differed from previous reports on standard maize lines. Somatic chromosomes of a JD line and the commonly used KYS line were compared by FISH in a hybrid of these lines. The pairing behavior of chromosomes 2 and 4 at pachytene stage in this hybrid was investigated using FISH with chromosome-specific probes. The homologues were fully synapsed, including the 5S rDNA and CentC sites on chromosome 2, and Cent4 and subtelomeric 4-12-1 sites on chromosome 4. This suggests that homologous chromosomes could pair through differential degrees of chromatin packaging in homologous arms differing in size. The results contribute to current knowledge of maize global diversity and also raise questions concerning the meiotic pairing of homologous chromosomes possibly differing in their amounts of repetitive DNA.

  1. In situ hybridization analysis of isodicentric X-chromosomes with short arm fusion

    DEFF Research Database (Denmark)

    Koch, J E; Kølvraa, S; Hertz, Jens Michael;

    1990-01-01

    We present here an alternative approach to the study of mosaic cell lines containing dicentric chromosomes. The approach is based on chromosome-specific non-radioactive in situ hybridization with centromere (alpha satellite DNA) probes. The hybridization analysis may be used as an alternative...... it for the analysis of two cases of isodicentric X-chromosomes. The approach is expected to be generally applicable, so that it may be applied to the scoring of other types of chromosomal mosaicism as well....

  2. Sequential cloning of chromosomes

    Science.gov (United States)

    Lacks, S.A.

    1995-07-18

    A method for sequential cloning of chromosomal DNA of a target organism is disclosed. A first DNA segment homologous to the chromosomal DNA to be sequentially cloned is isolated. The first segment has a first restriction enzyme site on either side. A first vector product is formed by ligating the homologous segment into a suitably designed vector. The first vector product is circularly integrated into the target organism`s chromosomal DNA. The resulting integrated chromosomal DNA segment includes the homologous DNA segment at either end of the integrated vector segment. The integrated chromosomal DNA is cleaved with a second restriction enzyme and ligated to form a vector-containing plasmid, which is replicated in a host organism. The replicated plasmid is then cleaved with the first restriction enzyme. Next, a DNA segment containing the vector and a segment of DNA homologous to a distal portion of the previously isolated DNA segment is isolated. This segment is then ligated to form a plasmid which is replicated within a suitable host. This plasmid is then circularly integrated into the target chromosomal DNA. The chromosomal DNA containing the circularly integrated vector is treated with a third, retrorestriction (class IIS) enzyme. The cleaved DNA is ligated to give a plasmid that is used to transform a host permissive for replication of its vector. The sequential cloning process continues by repeated cycles of circular integration and excision. The excision is carried out alternately with the second and third enzymes. 9 figs.

  3. Chromosomal mosaicism goes global

    Directory of Open Access Journals (Sweden)

    Yurov Yuri B

    2008-11-01

    Full Text Available Intercellular differences of chromosomal content in the same individual are defined as chromosomal mosaicism (alias intercellular or somatic genomic variations or, in a number of publications, mosaic aneuploidy. It has long been suggested that this phenomenon poorly contributes both to intercellular (interindividual diversity and to human disease. However, our views have recently become to change due to a series of communications demonstrated a higher incidence of chromosomal mosaicism in diseased individuals (major psychiatric disorders and autoimmune diseases as well as depicted chromosomal mosaicism contribution to genetic diversity, the central nervous system development, and aging. The later has been produced by significant achievements in the field of molecular cytogenetics. Recently, Molecular Cytogenetics has published an article by Maj Hulten and colleagues that has provided evidences for chromosomal mosaicism to underlie formation of germline aneuploidy in human female gametes using trisomy 21 (Down syndrome as a model. Since meiotic aneuploidy is suggested to be the leading genetic cause of human prenatal mortality and postnatal morbidity, these data together with previous findings define chromosomal mosaicism not as a casual finding during cytogenetic analyses but as a more significant biological phenomenon than previously recognized. Finally, the significance of chromosomal mosaicism can be drawn from the fact, that this phenomenon is involved in genetic diversity, normal and abnormal prenatal development, human diseases, aging, and meiotic aneuploidy, the intrinsic cause of which remains, as yet, unknown.

  4. Transfer of small chromosome fragments of Agropyron elongatum to wheat chromosome via asymmetric somatic hybridization

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    The chromosome constitution of hybrids and chromatin patterns of Agropyron elongatum(Host)Neviski in F5 somatic hybrid lines Ⅱ -1-3 and I-1-9 between Triticum aestivum L.and A.Elongatum were analyzed.Based on the statistic data of pollen mother cells,F5 I-1-9 and Ⅱ-1-3 had 20-21 bivalents with a frequency of 84.66% and 85.28%,of which,89.83% and 89.57% were ring bivalents.The result indicated that both hybrid lines were basically stable in the chromosome constitution and behavior.RAPD analysis showed that the two hybrids contained biparental and integrated DNA.GISH(Genome in situ hybridization)revealed that in the form of small chromosome segments,A.Elongatum chromatin was scattered on 4-6 wheat chromosomes near by the region of centromere and telomere in the two hybrid lines.SSR analysis indicated that A.Elongatum DNA segments were distributed on the 2A,5B,6B and 2D wheat chromosomes in the hybrids,which was in accordance with the GISH results that small-segments intercalated poly-site.

  5. CHROMOSOMES OF AMERICAN MARSUPIALS.

    Science.gov (United States)

    BIGGERS, J D; FRITZ, H I; HARE, W C; MCFEELY, R A

    1965-06-18

    Studies of the chromosomes of four American marsupials demonstrated that Caluromys derbianus and Marmosa mexicana have a diploid number of 14 chromosomes, and that Philander opossum and Didelphis marsupialis have a diploid number of 22. The karyotypes of C. derbianus and M. mexicana are similar, whereas those of P. opossum and D. marsupialis are dissimilar. If the 14-chromosome karyotype represents a reduction from a primitive number of 22, these observations suggest that the change has occurred independently in the American and Australasian forms.

  6. Sweeteners - sugar substitutes

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007492.htm Sweeteners - sugar substitutes To use the sharing features on this ... that are used in place of sweeteners with sugar (sucrose) or sugar alcohols . They may also be ...

  7. Synthesis of substituted pyrazines

    Energy Technology Data Exchange (ETDEWEB)

    Pagoria, Philip F.; Zhang, Mao Xi

    2016-10-04

    A method for synthesizing a pyrazine-containing material according to one embodiment includes contacting an iminodiacetonitrile derivative with a base and a reagent selected from a group consisting of hydroxylamine, a hydroxylamine salt, an aliphatic primary amine, a secondary amine, an aryl-substituted alkylamine a heteroaryl-substituted alkyl amine, an alcohol, an alkanolamine and an aryl alcoholamine. Additional methods and several reaction products are presented. ##STR00001##

  8. An SMC ATPase mutant disrupts chromosome segregation in Caulobacter.

    Science.gov (United States)

    Schwartz, Monica A; Shapiro, Lucy

    2011-12-01

    Accurate replication and segregation of the bacterial genome are essential for cell cycle progression. We have identified a single amino acid substitution in the Caulobacter structural maintenance of chromosomes (SMC) protein that disrupts chromosome segregation and cell division. The E1076Q point mutation in the SMC ATPase domain caused a dominant-negative phenotype in which DNA replication was able to proceed, but duplicated parS centromeres, normally found at opposite cell poles, remained at one pole. The cellular positions of other chromosomal loci were in the wild-type order relative to the parS centromere, but chromosomes remained unsegregated and appeared to be stacked upon one another. Purified SMC-E1076Q was deficient in ATP hydrolysis and exhibited abnormally stable binding to DNA. We propose that SMC spuriously links the duplicated chromosome immediately after passage of the replication fork. In wild-type cells, ATP hydrolysis opens the SMC dimer, freeing one chromosome to segregate to the opposite pole. The loss of ATP hydrolysis causes the SMC-E1076Q dimer to remain bound to both chromosomes, inhibiting segregation.

  9. Empirical codon substitution matrix

    Directory of Open Access Journals (Sweden)

    Gonnet Gaston H

    2005-06-01

    Full Text Available Abstract Background Codon substitution probabilities are used in many types of molecular evolution studies such as determining Ka/Ks ratios, creating ancestral DNA sequences or aligning coding DNA. Until the recent dramatic increase in genomic data enabled construction of empirical matrices, researchers relied on parameterized models of codon evolution. Here we present the first empirical codon substitution matrix entirely built from alignments of coding sequences from vertebrate DNA and thus provide an alternative to parameterized models of codon evolution. Results A set of 17,502 alignments of orthologous sequences from five vertebrate genomes yielded 8.3 million aligned codons from which the number of substitutions between codons were counted. From this data, both a probability matrix and a matrix of similarity scores were computed. They are 64 × 64 matrices describing the substitutions between all codons. Substitutions from sense codons to stop codons are not considered, resulting in block diagonal matrices consisting of 61 × 61 entries for the sense codons and 3 × 3 entries for the stop codons. Conclusion The amount of genomic data currently available allowed for the construction of an empirical codon substitution matrix. However, more sequence data is still needed to construct matrices from different subsets of DNA, specific to kingdoms, evolutionary distance or different amount of synonymous change. Codon mutation matrices have advantages for alignments up to medium evolutionary distances and for usages that require DNA such as ancestral reconstruction of DNA sequences and the calculation of Ka/Ks ratios.

  10. Chromosomal abnormalities and autism

    Directory of Open Access Journals (Sweden)

    Farida El-Baz

    2016-01-01

    Conclusion: Chromosomal abnormalities were not detected in the studied autistic children, and so the relation between the genetics and autism still needs further work up with different study methods and techniques.

  11. [Sex chromosomes and meiosis].

    Science.gov (United States)

    Guichaoua, M-R; Geoffroy-Siraudin, C; Tassistro, V; Ghalamoun-Slaimi, R; Perrin, J; Metzler-Guillemain, C

    2009-01-01

    Sex chromosome behaviour fundamentally differs between male and female meiosis. In oocyte, X chromosomes synapse giving a XX bivalent which is not recognizable in their morphology and behaviour from autosomal bivalents. In human male, X and Y chromosomes differ from one another in their morphology and their genetic content, leading to a limited pairing and preventing genetic recombination, excepted in homologous region PAR1. During pachytene stage of the first meiotic prophase, X and Y chromosomes undergo a progressive condensation and form a transcriptionally silenced peripheral XY body. The condensation of the XY bivalent during pachytene stage led us to describe four pachytene substages and to localize the pachytene checkpoint between substages 2 and 3. We also defined the pachytene index (PI=P1+P2/P1+P2+P3+P4) which is always less than 0.50 in normal meiosis. XY body undergoes decondensation at diplotene stage, but transcriptional inactivation of the two sex chromosomes or Meiotic Sex Chromosome Inactivation (MSCI) persists through to the end of spermatogenesis. Sex chromosome inactivation involves several proteins, some of them were now identified. Two isoforms of the HP1 protein, HP1beta and HP1gamma, are involved in the facultative heterochromatinization of the XY body, but the initiation of this process involves the phosphorylation of the protein H2AX by the kinase ATR whose recruitment depends on BRCA1. Extensive researches on the inactivation of the sex chromosomes during male meiosis will allow to a better understanding of some male infertilities.

  12. Chromosome doubling method

    Science.gov (United States)

    Kato, Akio

    2006-11-14

    The invention provides methods for chromosome doubling in plants. The technique overcomes the low yields of doubled progeny associated with the use of prior techniques for doubling chromosomes in plants such as grasses. The technique can be used in large scale applications and has been demonstrated to be highly effective in maize. Following treatment in accordance with the invention, plants remain amenable to self fertilization, thereby allowing the efficient isolation of doubled progeny plants.

  13. Activation of X Chromosome Inactivation

    NARCIS (Netherlands)

    C.M. Maduro (Cheryl)

    2016-01-01

    markdownabstractIn mammals, males are the heterogametic sex having an X chromosome and a Y chromosome whereas females have two X chromosomes. Despite originating from an ancient homologous autosomal pair, the X and Y chromosome now differ greatly in size and gene content after ~180 MY of evolution.

  14. Vibrio chromosomes share common history

    Directory of Open Access Journals (Sweden)

    Gevers Dirk

    2010-05-01

    Full Text Available Abstract Background While most gamma proteobacteria have a single circular chromosome, Vibrionales have two circular chromosomes. Horizontal gene transfer is common among Vibrios, and in light of this genetic mobility, it is an open question to what extent the two chromosomes themselves share a common history since their formation. Results Single copy genes from each chromosome (142 genes from chromosome I and 42 genes from chromosome II were identified from 19 sequenced Vibrionales genomes and their phylogenetic comparison suggests consistent phylogenies for each chromosome. Additionally, study of the gene organization and phylogeny of the respective origins of replication confirmed the shared history. Conclusions Thus, while elements within the chromosomes may have experienced significant genetic mobility, the backbones share a common history. This allows conclusions based on multilocus sequence analysis (MLSA for one chromosome to be applied equally to both chromosomes.

  15. "Chromosome": a knowledge-based system for the chromosome classification.

    Science.gov (United States)

    Ramstein, G; Bernadet, M

    1993-01-01

    Chromosome, a knowledge-based analysis system has been designed for the classification of human chromosomes. Its aim is to perform an optimal classification by driving a tool box containing the procedures of image processing, pattern recognition and classification. This paper presents the general architecture of Chromosome, based on a multiagent system generator. The image processing tool box is described from the met aphasic enhancement to the fine classification. Emphasis is then put on the knowledge base intended for the chromosome recognition. The global classification process is also presented, showing how Chromosome proceeds to classify a given chromosome. Finally, we discuss further extensions of the system for the karyotype building.

  16. Currency Substitution in Turkey

    Directory of Open Access Journals (Sweden)

    Ismail H. Genc

    2005-01-01

    Full Text Available We investigated whether the recent depreciations in the Turkish currency (Lira resulted in the currency substitution away from Lira by using quarterly data over the period from 1987:1 to 2000: 2 with M1 and M2 monetary aggregates and income, interest rate and exchange rate. Other than the variety of monetary aggregates, we tried different ways of including the interest rate into the models to ensure the robustness of our results. Our analysis shows that the currency substitution in fact happened with Lira.

  17. Chromosome numbers in Bromeliaceae

    Directory of Open Access Journals (Sweden)

    Cotias-de-Oliveira Ana Lúcia Pires

    2000-01-01

    Full Text Available The present study reports chromosome numbers of 17 species of Bromeliaceae, belonging to the genera Encholirium, Bromelia, Orthophytum, Hohenbergia, Billbergia, Neoglaziovia, Aechmea, Cryptanthus and Ananas. Most species present 2n = 50, however, Bromelia laciniosa, Orthophytum burle-marxii and O. maracasense are polyploids with 2n = 150, 2n = 100 and 2n = 150, respectively, while for Cryptanthus bahianus, 2n = 34 + 1-4B. B chromosomes were observed in Bromelia plumieri and Hohenbergia aff. utriculosa. The chromosome number of all species was determined for the first time, except for Billbergia chlorosticta and Cryptanthus bahianus. Our data supports the hypothesis of a basic number of x = 25 for the Bromeliaceae family and decreasing aneuploidy in the genus Cryptanthus.

  18. Those amazing dinoflagellate chromosomes

    Institute of Scientific and Technical Information of China (English)

    PETER J RIZZO

    2003-01-01

    Dinoflagellates are a very large and diverse group of eukaryotic algae that play a major role in aquatic food webs of both fresh water and marine habitats. Moreover, the toxic members of this group pose a health threat in the form of red tides. Finally, dinoflagellates are of great evolutionary importance,because of their taxonomic position, and their unusual chromosome structure and composition. While the cytoplasm of dinoflagellates is typically eukaryotic, the nucleus is unique when compared to the nucleus of other eukaryotes. More specifically, while the chromosomes of all other eukaryotes contain histones,dinoflagellate chromosomes lack histones completely. There are no known exceptions to this observation: all dinoflagellates lack histones, and all other eukaryotes contain histones. Nevertheless, dinoflagellates remain a relatively unstudied group of eukaryotes.

  19. Assignment of genes encoding metallothioneins I and II to Chinese hamster chromosomes 3. Evidence for the role of chromosome rearrangement in gene amplification

    Energy Technology Data Exchange (ETDEWEB)

    Stallings, R.L.; Munk, A.C.; Longmire, J.L.; Hildebrand, C.E.; Crawford, B.D.

    1984-12-01

    Cadmium resistant (Cd/sup r/) variants with coordinately amplified metallothionein I and II (MTI and MTII) genes have been derived from both Chinese hamster ovary and near-euploid Chinese hamster cell lines. Cytogenetic analyses of Cd/sup r/ variants consistently revealed breakage and rearrangement involving chromosome 3p. In situ hybridization with Chinese hamster MT-encoding cDNA probe localized amplified MT gene sequences near the translocation breakpoint involving chromosome 3p. These observations suggested that both functionally related, isometallothionein loci are linked on Chinese hamster chromosome 3. Southern blot analyses of DNAs isolated from a panel of Chinese hamster x mouse somatic cell hybrids which segregate hamster chromosomes confirmed that both MTI and MTII are located on chromosome 3. The authors speculate that rearrangement of chromosome 3p could be causally involved with the amplification of MT genes in Cd/sup r/ hamster cell lines. 34 references, 3 figures, 1 table.

  20. Virus evolution reveals an exclusive role for LEDGF/p75 in chromosomal tethering of HIV.

    Directory of Open Access Journals (Sweden)

    Anneleen Hombrouck

    2007-03-01

    Full Text Available Retroviruses by definition insert their viral genome into the host cell chromosome. Although the key player of retroviral integration is viral integrase, a role for cellular cofactors has been proposed. Lentiviral integrases use the cellular protein LEDGF/p75 to tether the preintegration complex to the chromosome, although the existence of alternative host proteins substituting for the function of LEDGF/p75 in integration has been proposed. Truncation mutants of LEDGF/p75 lacking the chromosome attachment site strongly inhibit HIV replication by competition for the interaction with integrase. In an attempt to select HIV strains that can overcome the inhibition, we now have used T-cell lines that stably express a C-terminal fragment of LEDGF/p75. Despite resistance development, the affinity of integrase for LEDGF/p75 is reduced and replication kinetics in human primary T cells is impaired. Detection of the integrase mutations A128T and E170G at key positions in the LEDGF/p75-integrase interface provides in vivo evidence for previously reported crystallographic data. Moreover, the complementary inhibition by LEDGF/p75 knockdown and mutagenesis at the integrase-LEDGF/p75 interface points to the incapability of HIV to circumvent LEDGF/p75 function during proviral integration. Altogether, the data provide a striking example of the power of viral molecular evolution. The results underline the importance of the LEDGF/p75 HIV-1 interplay as target for innovative antiviral therapy. Moreover, the role of LEDGF/p75 in targeting integration will stimulate research on strategies to direct gene therapy vectors into safe landing sites.

  1. 小麦-簇毛麦属间染色体易位系的高效诱导%High Induction of Intergeneric Chromosome Translocation Lines Between Wheat and Haynaldia villosa

    Institute of Scientific and Technical Information of China (English)

    曹亚萍; 别同德; 陈佩度; 范绍强; 周元成; 张姝敏

    2011-01-01

    A set of materials with Triticum aestivum-Haynaldia villosa translocation chromosomes were created using cv. ‘ Chinese Spring’ (CS)as female and Triticum durum-Haynaldia villosa amphiploid as male whose pollen was treated with 60Co-γ-ray in different dose. Then the set of materials were backcrossed with CS or self-crossed, H.villosa chromosome segments were reserved in M1 or BC1so that alien genes were transferred into wheat. The results showed that frequency of induced translocation chromosomes were significant different using different irradiation doses of 60Co-γ-ray. The plants with T. aestivum-H. villosa translocations induced by 12 Gy and 8 Gy hold 76. 7%and 50. 0% in M1 generation,respectively, and better translocations types were induced by 60Co-γ-ray with 12 Gy dose. 67.6% of these translocations were passed from M1 to BC1 ,and 96. 4% from BC1 to BC2. Alien whole chromosomes were rapidly lost, some pure translocations were obtained in BC2F2.%利用60Coγ射线以不同剂量照射硬粒小麦-簇毛麦双二倍体即将成熟的花粉,将其授于母本中国春,创造出一批包含小麦-簇毛麦易住染色体的材料,对这些材料用中国春进行连续回交或自交,可有效保留簇毛麦染色体片段,实现外源基因的转移.研究结果表明,60Coγ射线照射花粉后产生易位染色体的频率因剂量不同而有显著差异,12 Gy和8 Gy剂量照射后杂交的M1群体中,产生小麦-簇毛麦易位染色体的单株分别占调查总数的76.7%和50.0%,均显著高于用其他方法创造易住的频率,并且12 Gy较8 Gy产生了更优的易住类型;创制的易位染色体有67.6%可以从M1传递到BC1,BC1的易位染色体有96.4%可传递到BC,;在回交后代中,加以人为选择,整条簇毛麦染色体很快丢失,至BC2F2即有纯合易位株出现.

  2. Biological activities of substituted trichostatic acid derivatives

    Indian Academy of Sciences (India)

    Cédric Charrier; Joëlle Roche; Jean-Pierre Gesson; Philippe Bertrand

    2009-07-01

    New substituted trichostatic acid derivatives have been synthesized and evaluated for their biological activities towards the H661 non-small lung cancer cell line. These syntheses were achieved by alkylation of propiophenones to introduce the side chain with a terminal precursor of hydroxamic acid and aminobenzamide derivatives. The first fluorinated derivatives of trichostatic acid are described, such as 6-fluoro trichostatin A, with antiproliferative activities in the micromolar range and with histone deacetylase inhibitory activity.

  3. Chromosomal rearrangements in cattle and pigs revealed by chromosome microdissection and chromosome painting

    Directory of Open Access Journals (Sweden)

    Yerle Martine

    2003-11-01

    Full Text Available Abstract A pericentric inversion of chromosome 4 in a boar, as well as a case of (2q-;5p+ translocation mosaicism in a bull were analysed by chromosome painting using probes generated by conventional microdissection. For the porcine inversion, probes specific for p arms and q arms were produced and hybridised simultaneously on metaphases of a heterozygote carrier. In the case of the bovine translocation, two whole chromosome probes (chromosome 5, and derived chromosome 5 were elaborated and hybridised independently on chromosomal preparations of the bull who was a carrier of the mosaic translocation. The impossibility of differentiating chromosomes 2 and der(2 from other chromosomes of the metaphases did not allow the production of painting probes for these chromosomes. For all experiments, the quality of painting was comparable to that usually observed with probes obtained from flow-sorted chromosomes. The results obtained allowed confirmation of the interpretations proposed with G-banding karyotype analyses. In the bovine case, however, the reciprocity of the translocation could not be proven. The results presented in this paper show the usefulness of the microdissection technique for characterising chromosomal rearrangements in species for which commercial probes are not available. They also confirmed that the main limiting factor of the technique is the quality of the chromosomal preparations, which does not allow the identification of target chromosomes or chromosome fragments in all cases.

  4. Simulating currency substitution bias

    NARCIS (Netherlands)

    M. Boon (Martin); C.J.M. Kool (Clemens); C.G. de Vries (Casper)

    1989-01-01

    textabstractThe sign and size of estimates of the elasticity of currency substitution critically depend on the definition of the oppurtunity costs of holding money. We investigate possible biases by means of Monte Carlo experiments, as sufficient real data are not available.

  5. Saving Outweighs Substituting

    Institute of Scientific and Technical Information of China (English)

    Sophia

    2007-01-01

    @@ Energy crisis has become great challenge to the whole world.As the vehicle population keeps soaring in China,effectie countermeasures should be taken timely to deal with global energy crisis.There are two ways out:one is to substitute and one is to save.

  6. Chromosomal rearrangement interferes with meiotic X chromosome inactivation

    OpenAIRE

    Homolka, David; Ivanek, Robert; Capkova, Jana; Jansa, Petr; Forejt, Jiri

    2007-01-01

    Heterozygosity for certain mouse and human chromosomal rearrangements is characterized by the incomplete meiotic synapsis of rearranged chromosomes, by their colocalization with the XY body in primary spermatocytes, and by male-limited sterility. Previously, we argued that such X–autosomal associations could interfere with meiotic sex chromosome inactivation. Recently, supporting evidence has reported modifications of histones in rearranged chromosomes by a process called the meiotic silencin...

  7. The DNA sequence of the human X chromosome.

    Science.gov (United States)

    Ross, Mark T; Grafham, Darren V; Coffey, Alison J; Scherer, Steven; McLay, Kirsten; Muzny, Donna; Platzer, Matthias; Howell, Gareth R; Burrows, Christine; Bird, Christine P; Frankish, Adam; Lovell, Frances L; Howe, Kevin L; Ashurst, Jennifer L; Fulton, Robert S; Sudbrak, Ralf; Wen, Gaiping; Jones, Matthew C; Hurles, Matthew E; Andrews, T Daniel; Scott, Carol E; Searle, Stephen; Ramser, Juliane; Whittaker, Adam; Deadman, Rebecca; Carter, Nigel P; Hunt, Sarah E; Chen, Rui; Cree, Andrew; Gunaratne, Preethi; Havlak, Paul; Hodgson, Anne; Metzker, Michael L; Richards, Stephen; Scott, Graham; Steffen, David; Sodergren, Erica; Wheeler, David A; Worley, Kim C; Ainscough, Rachael; Ambrose, Kerrie D; Ansari-Lari, M Ali; Aradhya, Swaroop; Ashwell, Robert I S; Babbage, Anne K; Bagguley, Claire L; Ballabio, Andrea; Banerjee, Ruby; Barker, Gary E; Barlow, Karen F; Barrett, Ian P; Bates, Karen N; Beare, David M; Beasley, Helen; Beasley, Oliver; Beck, Alfred; Bethel, Graeme; Blechschmidt, Karin; Brady, Nicola; Bray-Allen, Sarah; Bridgeman, Anne M; Brown, Andrew J; Brown, Mary J; Bonnin, David; Bruford, Elspeth A; Buhay, Christian; Burch, Paula; Burford, Deborah; Burgess, Joanne; Burrill, Wayne; Burton, John; Bye, Jackie M; Carder, Carol; Carrel, Laura; Chako, Joseph; Chapman, Joanne C; Chavez, Dean; Chen, Ellson; Chen, Guan; Chen, Yuan; Chen, Zhijian; Chinault, Craig; Ciccodicola, Alfredo; Clark, Sue Y; Clarke, Graham; Clee, Chris M; Clegg, Sheila; Clerc-Blankenburg, Kerstin; Clifford, Karen; Cobley, Vicky; Cole, Charlotte G; Conquer, Jen S; Corby, Nicole; Connor, Richard E; David, Robert; Davies, Joy; Davis, Clay; Davis, John; Delgado, Oliver; Deshazo, Denise; Dhami, Pawandeep; Ding, Yan; Dinh, Huyen; Dodsworth, Steve; Draper, Heather; Dugan-Rocha, Shannon; Dunham, Andrew; Dunn, Matthew; Durbin, K James; Dutta, Ireena; Eades, Tamsin; Ellwood, Matthew; Emery-Cohen, Alexandra; Errington, Helen; Evans, Kathryn L; Faulkner, Louisa; Francis, Fiona; Frankland, John; Fraser, Audrey E; Galgoczy, Petra; Gilbert, James; Gill, Rachel; Glöckner, Gernot; Gregory, Simon G; Gribble, Susan; Griffiths, Coline; Grocock, Russell; Gu, Yanghong; Gwilliam, Rhian; Hamilton, Cerissa; Hart, Elizabeth A; Hawes, Alicia; Heath, Paul D; Heitmann, Katja; Hennig, Steffen; Hernandez, Judith; Hinzmann, Bernd; Ho, Sarah; Hoffs, Michael; Howden, Phillip J; Huckle, Elizabeth J; Hume, Jennifer; Hunt, Paul J; Hunt, Adrienne R; Isherwood, Judith; Jacob, Leni; Johnson, David; Jones, Sally; de Jong, Pieter J; Joseph, Shirin S; Keenan, Stephen; Kelly, Susan; Kershaw, Joanne K; Khan, Ziad; Kioschis, Petra; Klages, Sven; Knights, Andrew J; Kosiura, Anna; Kovar-Smith, Christie; Laird, Gavin K; Langford, Cordelia; Lawlor, Stephanie; Leversha, Margaret; Lewis, Lora; Liu, Wen; Lloyd, Christine; Lloyd, David M; Loulseged, Hermela; Loveland, Jane E; Lovell, Jamieson D; Lozado, Ryan; Lu, Jing; Lyne, Rachael; Ma, Jie; Maheshwari, Manjula; Matthews, Lucy H; McDowall, Jennifer; McLaren, Stuart; McMurray, Amanda; Meidl, Patrick; Meitinger, Thomas; Milne, Sarah; Miner, George; Mistry, Shailesh L; Morgan, Margaret; Morris, Sidney; Müller, Ines; Mullikin, James C; Nguyen, Ngoc; Nordsiek, Gabriele; Nyakatura, Gerald; O'Dell, Christopher N; Okwuonu, Geoffery; Palmer, Sophie; Pandian, Richard; Parker, David; Parrish, Julia; Pasternak, Shiran; Patel, Dina; Pearce, Alex V; Pearson, Danita M; Pelan, Sarah E; Perez, Lesette; Porter, Keith M; Ramsey, Yvonne; Reichwald, Kathrin; Rhodes, Susan; Ridler, Kerry A; Schlessinger, David; Schueler, Mary G; Sehra, Harminder K; Shaw-Smith, Charles; Shen, Hua; Sheridan, Elizabeth M; Shownkeen, Ratna; Skuce, Carl D; Smith, Michelle L; Sotheran, Elizabeth C; Steingruber, Helen E; Steward, Charles A; Storey, Roy; Swann, R Mark; Swarbreck, David; Tabor, Paul E; Taudien, Stefan; Taylor, Tineace; Teague, Brian; Thomas, Karen; Thorpe, Andrea; Timms, Kirsten; Tracey, Alan; Trevanion, Steve; Tromans, Anthony C; d'Urso, Michele; Verduzco, Daniel; Villasana, Donna; Waldron, Lenee; Wall, Melanie; Wang, Qiaoyan; Warren, James; Warry, Georgina L; Wei, Xuehong; West, Anthony; Whitehead, Siobhan L; Whiteley, Mathew N; Wilkinson, Jane E; Willey, David L; Williams, Gabrielle; Williams, Leanne; Williamson, Angela; Williamson, Helen; Wilming, Laurens; Woodmansey, Rebecca L; Wray, Paul W; Yen, Jennifer; Zhang, Jingkun; Zhou, Jianling; Zoghbi, Huda; Zorilla, Sara; Buck, David; Reinhardt, Richard; Poustka, Annemarie; Rosenthal, André; Lehrach, Hans; Meindl, Alfons; Minx, Patrick J; Hillier, Ladeana W; Willard, Huntington F; Wilson, Richard K; Waterston, Robert H; Rice, Catherine M; Vaudin, Mark; Coulson, Alan; Nelson, David L; Weinstock, George; Sulston, John E; Durbin, Richard; Hubbard, Tim; Gibbs, Richard A; Beck, Stephan; Rogers, Jane; Bentley, David R

    2005-03-17

    The human X chromosome has a unique biology that was shaped by its evolution as the sex chromosome shared by males and females. We have determined 99.3% of the euchromatic sequence of the X chromosome. Our analysis illustrates the autosomal origin of the mammalian sex chromosomes, the stepwise process that led to the progressive loss of recombination between X and Y, and the extent of subsequent degradation of the Y chromosome. LINE1 repeat elements cover one-third of the X chromosome, with a distribution that is consistent with their proposed role as way stations in the process of X-chromosome inactivation. We found 1,098 genes in the sequence, of which 99 encode proteins expressed in testis and in various tumour types. A disproportionately high number of mendelian diseases are documented for the X chromosome. Of this number, 168 have been explained by mutations in 113 X-linked genes, which in many cases were characterized with the aid of the DNA sequence.

  8. IDENTIFICATION OF A TUMOR-MARKER CHROMOSOME BY FLOW SORTING, DNA AMPLIFICATION INVITRO, AND INSITU HYBRIDIZATION OF THE AMPLIFIED PRODUCT

    NARCIS (Netherlands)

    BOSCHMAN, GA; BUYS, CHCM; VANDERVEEN, AY; RENS, W; OSINGA, J; SLATER, RM; ATEN, JA

    1993-01-01

    A method combining flow sorting and molecular cytogenetic techniques for the identification of unknown marker chromosomes is described. In this study, the bladder tumor cell line J82 was used, which was known to carry a marker chromosome of the size of chromosome 7 in every cell. From the cytogeneti

  9. Caenorhabditis elegans histone methyltransferase MET-2 shields the male X chromosome from checkpoint machinery and mediates meiotic sex chromosome inactivation.

    OpenAIRE

    Checchi, Paula M.; JoAnne Engebrecht

    2011-01-01

    Meiosis is a specialized form of cellular division that results in the precise halving of the genome to produce gametes for sexual reproduction. Checkpoints function during meiosis to detect errors and subsequently to activate a signaling cascade that prevents the formation of aneuploid gametes. Indeed, asynapsis of a homologous chromosome pair elicits a checkpoint response that can in turn trigger germline apoptosis. In a heterogametic germ line, however, sex chromosomes proceed through meio...

  10. Caenorhabditis elegans histone methyltransferase MET-2 shields the male X chromosome from checkpoint machinery and mediates meiotic sex chromosome inactivation.

    Directory of Open Access Journals (Sweden)

    Paula M Checchi

    2011-09-01

    Full Text Available Meiosis is a specialized form of cellular division that results in the precise halving of the genome to produce gametes for sexual reproduction. Checkpoints function during meiosis to detect errors and subsequently to activate a signaling cascade that prevents the formation of aneuploid gametes. Indeed, asynapsis of a homologous chromosome pair elicits a checkpoint response that can in turn trigger germline apoptosis. In a heterogametic germ line, however, sex chromosomes proceed through meiosis with unsynapsed regions and are not recognized by checkpoint machinery. We conducted a directed RNAi screen in Caenorhabditis elegans to identify regulatory factors that prevent recognition of heteromorphic sex chromosomes as unpaired and uncovered a role for the SET domain histone H3 lysine 9 histone methyltransferase (HMTase MET-2 and two additional HMTases in shielding the male X from checkpoint machinery. We found that MET-2 also mediates the transcriptional silencing program of meiotic sex chromosome inactivation (MSCI but not meiotic silencing of unsynapsed chromatin (MSUC, suggesting that these processes are distinct. Further, MSCI and checkpoint shielding can be uncoupled, as double-strand breaks targeted to an unpaired, transcriptionally silenced extra-chromosomal array induce checkpoint activation in germ lines depleted for met-2. In summary, our data uncover a mechanism by which repressive chromatin architecture enables checkpoint proteins to distinguish between the partnerless male X chromosome and asynapsed chromosomes thereby shielding the lone X from inappropriate activation of an apoptotic program.

  11. Caenorhabditis elegans histone methyltransferase MET-2 shields the male X chromosome from checkpoint machinery and mediates meiotic sex chromosome inactivation.

    Science.gov (United States)

    Checchi, Paula M; Engebrecht, JoAnne

    2011-09-01

    Meiosis is a specialized form of cellular division that results in the precise halving of the genome to produce gametes for sexual reproduction. Checkpoints function during meiosis to detect errors and subsequently to activate a signaling cascade that prevents the formation of aneuploid gametes. Indeed, asynapsis of a homologous chromosome pair elicits a checkpoint response that can in turn trigger germline apoptosis. In a heterogametic germ line, however, sex chromosomes proceed through meiosis with unsynapsed regions and are not recognized by checkpoint machinery. We conducted a directed RNAi screen in Caenorhabditis elegans to identify regulatory factors that prevent recognition of heteromorphic sex chromosomes as unpaired and uncovered a role for the SET domain histone H3 lysine 9 histone methyltransferase (HMTase) MET-2 and two additional HMTases in shielding the male X from checkpoint machinery. We found that MET-2 also mediates the transcriptional silencing program of meiotic sex chromosome inactivation (MSCI) but not meiotic silencing of unsynapsed chromatin (MSUC), suggesting that these processes are distinct. Further, MSCI and checkpoint shielding can be uncoupled, as double-strand breaks targeted to an unpaired, transcriptionally silenced extra-chromosomal array induce checkpoint activation in germ lines depleted for met-2. In summary, our data uncover a mechanism by which repressive chromatin architecture enables checkpoint proteins to distinguish between the partnerless male X chromosome and asynapsed chromosomes thereby shielding the lone X from inappropriate activation of an apoptotic program.

  12. Alteration of chromosome behavior and synchronization of parental chromosomes after successive generations in Brassica napus x Orychophragmus violaceus hybrids.

    Science.gov (United States)

    Zhao, Zhigang; Ma, Ni; Li, Zaiyun

    2007-02-01

    In an earlier study, the progenies of intergeneric hybrids Brassica napus (2n = 38) x Orychophragmus violaceus (2n = 24) were investigated in successive generations (F1-F4) for the cytological phenomenon of parental genome separation during mitotic and meiotic division. In the present study, inbred lines (F5-F8) derived from 1 such hybrid were characterized for morphology, chromosome pairing behaviour, and genome composition. One F5 plant (2n = 31) with slightly yellow petals and 12:19 and 15:16 segregation ratios in its pollen mother cells (PMCs) produced F6 plants with distinct morphological characteristics and wide variations in fertility and chromosome numbers (2n = 25-38). F7 and F8 lines with distinctive morphology and wide ranges in chromsome numbers were established. In PMCs of F7 plants from 4 F6 plants, 0-12 labelled chromosomes from O. violaceus, which predominantly appeared as bivalents, were identified by genomic in situ hybridization. They behaved synchronously with B. napus chromosomes during meiotic division. The results provide molecular cytogenetic evidence of the inclusion of O. violaceus chromosomes in the original hybrids and the cytology in the hybrids documented earlier. They also show that chromosome behaviour was altered and the parental chromosomes became synchronized after successive generations.

  13. Electochemical detection of chromosome translocation

    DEFF Research Database (Denmark)

    Kwasny, Dorota; Dimaki, Maria; Silahtaroglu, Asli;

    2014-01-01

    Cytogenetics is a study of the cell structure with a main focus on chromosomes content and their structure. Chromosome abnormalities, such as translocations may cause various genetic disorders and heametological malignancies. Chromosome translocations are structural rearrangements of two...... chromosomes that results in formation of derivative chromosomes with a mixed DNA sequence. The method currently used for their detection is Fluorescent In Situ Hybridization, which requires a use of expensive, fluorescently labeled probes that target the derivative chromosomes. We present here a double...... hybridization approach developed for label-free detection of the chromosome translocations. For specific translocation detection it is necessary to determine that the two DNA sequences forming a derivative chromosome are connected, which is achieved by two subsequent hybridization steps. The electrochemical...

  14. Chromosome Variations And Human Behavior

    Science.gov (United States)

    Soudek, D.

    1974-01-01

    Article focused on the science of cytogenetics, which studied the transmission of the units of heredity called chromosomes, and considered the advantage of proper diagnosis of genetic diseases, treated on the chromosomal level. (Author/RK)

  15. Ring chromosome 13

    DEFF Research Database (Denmark)

    Brandt, C A; Hertz, Jens Michael; Petersen, M B;

    1992-01-01

    A stillborn male child with anencephaly and multiple malformations was found to have the karyotype 46,XY,r(13) (p11q21.1). The breakpoint at 13q21.1, determined by high resolution banding, is the most proximal breakpoint ever reported in patients with ring chromosome 13. In situ hybridisation...

  16. Chromosomes, cancer and radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Samouhos, E.

    1983-08-01

    Some specific chromosomal abnormalities are associated with certain cancers. The earliest description of such a specific association is the one of the Philadelphia chromosome and myelogenous leukemia (1960). Other congenital karyotype abnormalities are associated with specific cancers. Examples of these are Down's syndrome with leukemia and Klinefelter's syndrome with male breast cancer. Genetic diseases of increased chromosome breakage, or of defective chromosome repair, are associated with greatly increased cancer incidence. Three such diseases have been recognized: 1) Fanconi's anemia, associated with leukemias and lymphomas, 2) Bloom's syndrome, associated with acute leukemias and lymphosarcoma, and 3) ataxia telangiectasia, associated with Hodgkin's disease, leukemia, and lymphosarcomas. Ten percent of individuals with ataxia telangiectasia will develop one of these neoplasms. Individuals with certain of these syndromes display an unusually high radiosensitivity. Radiation therapy for cancers has been fatal in patients who received as low as 3000 rad. This remarkable radiosensitivity has been quantitated in cell cultures from such cases. Evidence suggests that the apparent sensitivity may reflect subnormal ability to repair radiation damage. The rapid proliferation of information in this field stems from the interdigitation of many disciplines and specialties, including cytogenetics, cell biology, molecular biology, epidemiology, radiobiology, and several others. This paper is intended for clinicians; it presents a structured analytic scheme for correlating and classifying this multidisciplinary information as it becomes available.

  17. The Y Chromosome

    Science.gov (United States)

    Offner, Susan

    2010-01-01

    The Y chromosome is of great interest to students and can be used to teach about many important biological concepts in addition to sex determination. This paper discusses mutation, recombination, mammalian sex determination, sex determination in general, and the evolution of sex determination in mammals. It includes a student activity that…

  18. Why Chromosome Palindromes?

    Directory of Open Access Journals (Sweden)

    Esther Betrán

    2012-01-01

    Full Text Available We look at sex-limited chromosome (Y or W evolution with particular emphasis on the importance of palindromes. Y chromosome palindromes consist of inverted duplicates that allow for local recombination in an otherwise nonrecombining chromosome. Since palindromes enable intrachromosomal gene conversion that can help eliminate deleterious mutations, they are often highlighted as mechanisms to protect against Y degeneration. However, the adaptive significance of recombination resides in its ability to decouple the evolutionary fates of linked mutations, leading to both a decrease in degeneration rate and an increase in adaptation rate. Our paper emphasizes the latter, that palindromes may exist to accelerate adaptation by increasing the potential targets and fixation rates of incoming beneficial mutations. This hypothesis helps reconcile two enigmatic features of the “palindromes as protectors” view: (1 genes that are not located in palindromes have been retained under purifying selection for tens of millions of years, and (2 under models that only consider deleterious mutations, gene conversion benefits duplicate gene maintenance but not initial fixation. We conclude by looking at ways to test the hypothesis that palindromes enhance the rate of adaptive evolution of Y-linked genes and whether this effect can be extended to palindromes on other chromosomes.

  19. Telomere dysfunction and chromosome instability

    Energy Technology Data Exchange (ETDEWEB)

    Murnane, John P., E-mail: jmurnane@radonc.ucsf.edu [Department of Radiation Oncology, University of California San Francisco, 2340 Sutter Street, San Francisco, CA 94143-1331 (United States)

    2012-02-01

    The ends of chromosomes are composed of a short repeat sequence and associated proteins that together form a cap, called a telomere, that keeps the ends from appearing as double-strand breaks (DSBs) and prevents chromosome fusion. The loss of telomeric repeat sequences or deficiencies in telomeric proteins can result in chromosome fusion and lead to chromosome instability. The similarity between chromosome rearrangements resulting from telomere loss and those found in cancer cells implicates telomere loss as an important mechanism for the chromosome instability contributing to human cancer. Telomere loss in cancer cells can occur through gradual shortening due to insufficient telomerase, the protein that maintains telomeres. However, cancer cells often have a high rate of spontaneous telomere loss despite the expression of telomerase, which has been proposed to result from a combination of oncogene-mediated replication stress and a deficiency in DSB repair in telomeric regions. Chromosome fusion in mammalian cells primarily involves nonhomologous end joining (NHEJ), which is the major form of DSB repair. Chromosome fusion initiates chromosome instability involving breakage-fusion-bridge (B/F/B) cycles, in which dicentric chromosomes form bridges and break as the cell attempts to divide, repeating the process in subsequent cell cycles. Fusion between sister chromatids results in large inverted repeats on the end of the chromosome, which amplify further following additional B/F/B cycles. B/F/B cycles continue until the chromosome acquires a new telomere, most often by translocation of the end of another chromosome. The instability is not confined to a chromosome that loses its telomere, because the instability is transferred to the chromosome donating a translocation. Moreover, the amplified regions are unstable and form extrachromosomal DNA that can reintegrate at new locations. Knowledge concerning the factors promoting telomere loss and its consequences is

  20. Chromosome 11q13 deletion syndrome

    Science.gov (United States)

    Kim, Yu-Seon; Kim, Gun-Ha; Byeon, Jung Hye; Eun, So-Hee

    2016-01-01

    Chromosome 11q13 deletion syndrome has been previously reported as either otodental syndrome or oculo-oto-dental syndrome. The otodental syndrome is characterized by dental abnormalities and high-frequency sensorineural hearing loss, and by ocular coloboma in some cases. The underlying genetic defect causing otodental syndrome is a hemizygous microdeletion involving the FGF3 gene on chromosome 11q13.3. Recently, a new form of severe deafness, microtia (small ear) and small teeth, without the appearance of eye abnormalities, was also reported. In this report, we describe a 1-year-old girl presenting with ptosis of the left upper eyelid, right auricular deformity, high-arched palate, delayed dentition, simian line on the right hand, microcephaly, and developmental delay. In this patient, we identified a deletion in the chromosome 11q13.2-q13.3 (2.75 Mb) region by using an array-comparative genomic hybridization analysis. The deletion in chromosome 11q13 results in a syndrome characterized by variable clinical manifestations. Some of these manifestations involve craniofacial dysmorphology and require a functional workup for hearing, ophthalmic examinations, and long-term dental care. PMID:28018436

  1. Equine herpesvirus 1 gene 12 can substitute for vmw65 in the growth of herpes simplex virus (HSV) type 1, allowing the generation of optimized cell lines for the propagation of HSV vectors with multiple immediate-early gene defects.

    Science.gov (United States)

    Thomas, S K; Lilley, C E; Latchman, D S; Coffin, R S

    1999-09-01

    Herpes simplex virus (HSV) has often been suggested for development as a vector, particularly for the nervous system. Considerable evidence has shown that for use of HSV as a vector, immediate-early (IE) gene expression must be minimized or abolished, otherwise such vectors are likely to be highly cytotoxic. Mutations of vmw65 which abolish IE promoter transactivating activity may also be included to reduce IE gene expression generally. However, when vmw65 mutations are combined with an IE gene deletion, such viruses are hard to propagate, even on cells which otherwise complement the IE gene deletion effectively. We have found that vmw65 mutants can be effectively grown on cell lines expressing equine herpesvirus 1 gene 12, a non-HSV homologue of vmw65 with little sequence similarity to its HSV counterpart. This prevents repair by homologous recombination of vmw65 mutations in the virus, which would occur if mutations were complemented by vmw65 itself. The gene 12 protein is not packaged into HSV virions, which is important if viruses grown on such cells are to be used as vectors. These results not only further strengthen the evidence for direct functional homology between and similar modes of action of the two proteins but have allowed the generation of gene 12-containing cell lines in which ICP4 and ICP27 expression is induced by virus infection (probably by ICP0) and which give efficient growth of viruses deficient in ICP27, ICP4, and vmw65 (the viruses also have ICP34.5/ORFP deleted). Efficient growth of such viruses has not previously been possible. As these viruses are highly deficient in IE gene expression generally, such virus-cell line combinations may provide an alternative to HSV vectors with deletions of all four of the regulatory IE genes which, for optimal growth, require cell lines containing all four IE genes but which are hard to generate due to the intrinsic cytotoxicity of each of the proteins.

  2. Dynamics of X Chromosome Inactivation

    NARCIS (Netherlands)

    F. Loos (Friedemann)

    2015-01-01

    markdownabstract__Abstract__ Dosage compensation evolved to account for the difference in expression of sex chromosome-linked genes. In mammals dosage compensation is achieved by inactivation of one X chromosome during early female embryogenesis in a process called X chromosome inactivation (XCI).

  3. D2类山羊草细胞质普通小麦核代换系 育性在不同光温条件下的差异%The Reaction to Phto-period and Temperature of Fertility the Different of the Wheat Nucleus Substitutional Lines of D2 Genus Aegilops Cytoplasm

    Institute of Scientific and Technical Information of China (English)

    徐洁; 陈升位; 杨德; 何蓓如

    2001-01-01

    The eleven wheat nucleus substitution Lines in D2 genus(Aegilops crassa,Aegilops vavilovii and Aegilops juvenalis) cy toplasm and three of cheir parents were sown in the five locations between latit ude of China.The results were shown in the followings:(1) There were some diffe rences in the DL sensitivity of wheat nucleus substitution lines strains of the three Aegilops types. According to the integral analysis Aegilops crassa response was one of the most sensitive in them,next was Aegilops vavilovii and then was Aegilops juvenalis.(2) There were differen t intensive effects of DL and AT on the fertility of D2 genus Agilops cyto plasm wheat nucleus substitution lines DL was basic factor and AT effect was sho wn in the similar DL condition. (3) The nucleoplasm intereffect was the genetic way of the response of wheat nucleus substitution line fertility of D2 genus Aegilops cytoplasm on light and temperature.%将D2类山羊草[粗厚山羊草(Ae.crassa)、牡山羊草(Ae.juvenalis)和瓦维洛 夫山羊草(Ae.vavilovii)]细胞质普通小麦核代换系于1997~1998年分别种植在不同 纬度 的5个地点,并进行分期播种。从不同地点核代换系和核亲本的育性表现,分析D2类山羊草 细胞质核代换系对日长、温度的敏感性及其差异。结果表明:(1)D2类山羊草细胞质小 麦核代换系的3种类型存在差异,粗厚山羊草对日长、温度反应最为敏感,其次是瓦维洛夫山 羊草,牡山羊草对光周期较钝感。(2)日长和温度两种生态因子对D2类山羊草细胞质核 代换系的育性变异的作用程度不同,日长是主控因子,温度在日长因子相近时方显示其作用 。(3)核质互作是D2类山羊草细胞质小麦核代换系育性对光温反应的遗传方式。

  4. Smart Substitutions for Healthy Cooking

    Science.gov (United States)

    ... Recognition & Awards Healthy Workplace Food and Beverage Toolkit Smart Substitutions Updated:Dec 16,2016 Healthy eating doesn’ ... mean giving up all the foods you love! Smart substitutions can help you maintain an overall healthy ...

  5. Rapid chromosome evolution in recently formed polyploids in Tragopogon (Asteraceae.

    Directory of Open Access Journals (Sweden)

    K Yoong Lim

    Full Text Available BACKGROUND: Polyploidy, frequently termed "whole genome duplication", is a major force in the evolution of many eukaryotes. Indeed, most angiosperm species have undergone at least one round of polyploidy in their evolutionary history. Despite enormous progress in our understanding of many aspects of polyploidy, we essentially have no information about the role of chromosome divergence in the establishment of young polyploid populations. Here we investigate synthetic lines and natural populations of two recently and recurrently formed allotetraploids Tragopogon mirus and T. miscellus (formed within the past 80 years to assess the role of aberrant meiosis in generating chromosomal/genomic diversity. That diversity is likely important in the formation, establishment and survival of polyploid populations and species. METHODOLOGY/PRINCIPAL FINDINGS: Applications of fluorescence in situ hybridisation (FISH to natural populations of T. mirus and T. miscellus suggest that chromosomal rearrangements and other chromosomal changes are common in both allotetraploids. We detected extensive chromosomal polymorphism between individuals and populations, including (i plants monosomic and trisomic for particular chromosomes (perhaps indicating compensatory trisomy, (ii intergenomic translocations and (iii variable sizes and expression patterns of individual ribosomal DNA (rDNA loci. We even observed karyotypic variation among sibling plants. Significantly, translocations, chromosome loss, and meiotic irregularities, including quadrivalent formation, were observed in synthetic (S(0 and S(1 generations polyploid lines. Our results not only provide a mechanism for chromosomal variation in natural populations, but also indicate that chromosomal changes occur rapidly following polyploidisation. CONCLUSIONS/SIGNIFICANCE: These data shed new light on previous analyses of genome and transcriptome structures in de novo and establishing polyploid species. Crucially our

  6. Evolutionarily diverged regulation of X-chromosomal genes as a primal event in mouse reproductive isolation.

    Science.gov (United States)

    Oka, Ayako; Takada, Toyoyuki; Fujisawa, Hironori; Shiroishi, Toshihiko

    2014-04-01

    Improper gene regulation is implicated in reproductive isolation, but its genetic and molecular bases are unknown. We previously reported that a mouse inter-subspecific X chromosome substitution strain shows reproductive isolation characterized by male-specific sterility due to disruption of meiotic entry in spermatogenesis. Here, we conducted comprehensive transcriptional profiling of the testicular cells of this strain by microarray. The results clearly revealed gross misregulation of gene expression in the substituted donor X chromosome. Such misregulation occurred prior to detectable spermatogenetic impairment, suggesting that it is a primal event in reproductive isolation. The misregulation of X-linked genes showed asymmetry; more genes were disproportionally downregulated rather than upregulated. Furthermore, this misregulation subsequently resulted in perturbation of global transcriptional regulation of autosomal genes, probably by cascading deleterious effects. Remarkably, this transcriptional misregulation was substantially restored by introduction of chromosome 1 from the same donor strain as the X chromosome. This finding implies that one of regulatory genes acting in trans for X-linked target genes is located on chromosome 1. This study collectively suggests that regulatory incompatibility is a major cause of reproductive isolation in the X chromosome substitution strain.

  7. X chromosome control of meiotic chromosome synapsis in mouse inter-subspecific hybrids.

    Directory of Open Access Journals (Sweden)

    Tanmoy Bhattacharyya

    2014-02-01

    Full Text Available Hybrid sterility (HS belongs to reproductive isolation barriers that safeguard the integrity of species in statu nascendi. Although hybrid sterility occurs almost universally among animal and plant species, most of our current knowledge comes from the classical genetic studies on Drosophila interspecific crosses or introgressions. With the house mouse subspecies Mus m. musculus and Mus m. domesticus as a model, new research tools have become available for studies of the molecular mechanisms and genetic networks underlying HS. Here we used QTL analysis and intersubspecific chromosome substitution strains to identify a 4.7 Mb critical region on Chromosome X (Chr X harboring the Hstx2 HS locus, which causes asymmetrical spermatogenic arrest in reciprocal intersubspecific F1 hybrids. Subsequently, we mapped autosomal loci on Chrs 3, 9 and 13 that can abolish this asymmetry. Combination of immunofluorescent visualization of the proteins of synaptonemal complexes with whole-chromosome DNA FISH on pachytene spreads revealed that heterosubspecific, unlike consubspecific, homologous chromosomes are predisposed to asynapsis in F1 hybrid male and female meiosis. The asynapsis is under the trans- control of Hstx2 and Hst1/Prdm9 hybrid sterility genes in pachynemas of male but not female hybrids. The finding concurred with the fertility of intersubpecific F1 hybrid females homozygous for the Hstx2(Mmm allele and resolved the apparent conflict with the dominance theory of Haldane's rule. We propose that meiotic asynapsis in intersubspecific hybrids is a consequence of cis-acting mismatch between homologous chromosomes modulated by the trans-acting Hstx2 and Prdm9 hybrid male sterility genes.

  8. Chromosomal breakpoints characterization of two supernumerary ring chromosomes 20.

    Science.gov (United States)

    Guediche, N; Brisset, S; Benichou, J-J; Guérin, N; Mabboux, P; Maurin, M-L; Bas, C; Laroudie, M; Picone, O; Goldszmidt, D; Prévot, S; Labrune, P; Tachdjian, G

    2010-02-01

    The occurrence of an additional ring chromosome 20 is a rare chromosome abnormality, and no common phenotype has been yet described. We report on two new patients presenting with a supernumerary ring chromosome 20 both prenatally diagnosed. The first presented with intrauterine growth retardation and some craniofacial dysmorphism, and the second case had a normal phenotype except for obesity. Conventional cytogenetic studies showed for each patient a small supernumerary marker chromosome (SMC). Using fluorescence in situ hybridization, these SMCs corresponded to ring chromosomes 20 including a part of short and long arms of chromosome 20. Detailed molecular cytogenetic characterization showed different breakpoints (20p11.23 and 20q11.23 for Patient 1 and 20p11.21 and 20q11.21 for Patient 2) and sizes of the two ring chromosomes 20 (13.6 Mb for case 1 and 4.8 Mb for case 2). Review of the 13 case reports of an extra r(20) ascertained postnatally (8 cases) and prenatally (5 cases) showed varying degrees of phenotypic abnormalities. We document a detailed molecular cytogenetic chromosomal breakpoints characterization of two cases of supernumerary ring chromosomes 20. These results emphasize the need to characterize precisely chromosomal breakpoints of supernumerary ring chromosomes 20 in order to establish genotype-phenotype correlation. This report may be helpful for prediction of natural history and outcome, particularly in prenatal diagnosis.

  9. A semidwarf phenotype of barley uzu results from a nucleotide substitution in the gene encoding a putative brassinosteroid receptor.

    Science.gov (United States)

    Chono, Makiko; Honda, Ichiro; Zeniya, Haruko; Yoneyama, Koichi; Saisho, Daisuke; Takeda, Kazuyoshi; Takatsuto, Suguru; Hoshino, Tsuguhiro; Watanabe, Yoshiaki

    2003-11-01

    Brassinosteroids (BRs) play important roles throughout plant growth and development. Despite the importance of clarifying the mechanism of BR-related growth regulation in cereal crops, BR-related cereal mutants have been identified only in rice (Oryza sativa). We previously found that semidwarf barley (Hordeum vulgare) accessions carrying the "uzu" gene, called "uzu" barley in Japan, are non-responding for brassinolide (BL). We then performed chemical and molecular analyses to clarify the mechanisms of uzu dwarfism using isogenic line pairs of uzu gene. The response of the uzu line to BL was significantly lower than that of its corresponding normal line. Measurement of BRs showed that the uzu line accumulates BRs, similar to known BR-insensitive mutants. The marker synteny of rice and barley chromosomes suggests that the uzu gene may be homologous to rice D61, a rice homolog of Arabidopsis BR-insensitive 1 (BRI1), encoding a BR-receptor protein. A barley homolog of BRI1, HvBRI1, was isolated by using degenerate primers. A comparison of HvBRI1 sequences in uzu and normal barley varieties showed that the uzu phenotype is correlated with a single nucleotide substitution. This substitution results in an amino acid change at a highly conserved residue in the kinase domain of the BR-receptor protein. These results may indicate that uzu dwarfism is caused by the missense mutation in HvBRI1. The uzu gene is being introduced into all hull-less barley cultivars in Japan as an effective dwarf gene for practical use, and this is the first report about an agronomically important mutation related to BRs.

  10. Familial complex chromosomal rearrangement resulting in a recombinant chromosome.

    Science.gov (United States)

    Berend, Sue Ann; Bodamer, Olaf A F; Shapira, Stuart K; Shaffer, Lisa G; Bacino, Carlos A

    2002-05-15

    Familial complex chromosomal rearrangements (CCRs) are rare and tend to involve fewer breakpoints and fewer chromosomes than CCRs that are de novo in origin. We report on a CCR identified in a child with congenital heart disease and dysmorphic features. Initially, the child's karyotype was thought to involve a straightforward three-way translocation between chromosomes 3, 8, and 16. However, after analyzing the mother's chromosomes, the mother was found to have a more complex rearrangement that resulted in a recombinant chromosome in the child. The mother's karyotype included an inverted chromosome 2 and multiple translocations involving chromosomes 3, 5, 8, and 16. No evidence of deletion or duplication that could account for the clinical findings in the child was identified.

  11. 人嗜碱性粒细胞肿瘤细胞系KU812F检灏牛乳及其替代品致敏性方法的建立%Construction of an in vitro Allergy Reaction Evaluation Method for Cow Milk and Its Substitutes Using Human Leukemia Cell Line KU812F

    Institute of Scientific and Technical Information of China (English)

    丛艳君; 任发政

    2011-01-01

    比较牛乳及其替代品释放组胺的能力,以建立体外细胞检测牛乳及替代品疑似过敏原组分致敏性的检测方法。以嗜碱性粒细胞KU812F为研究对象,通过牛乳过敏患者血清的孵育,使细胞处于致敏状态,再以牛乳及其替代品过敏原作为激发物,使细胞脱颗粒释放组胺。结果表明:利用嗜碱性粒细胞KU812F检测牛乳及替代制品组胺释放量的方法具有较高的可靠性及重现性,细胞释放组胺的量与过敏原的剂量相关,在一定的剂量范围内,组胺的释放率与过敏原的剂量呈正比,组胺释放率达到最大之后,组胺释放率与剂量呈负相关。%This study aimed to construct an in vitro cellular assay for suspected allergenic components of cow milk and its substitutes using human leukemia cell line KU812F, an immature prebasophillic cell line based on their histamine release ability. KU812F was differentiated into basophils by incubation with serum from cow milk allergic people. The release of histamine from differentiated KU812F cells was monitored after sensitization with either cow milk or its substitutes. The results showed that this in vitro assay was highly reliable and reproducible in determining histamine release from KU812F cells after respective sensitization with cow milk and its products. Cow milk and its substitutes differed in their histamine release ability. Cow milk allergen induced histamine release in a dose-dependent manner. Specifically, a positive relationship was observed in a defmed range of allergen dose, followed by a negative relationship after maximum histamine release.

  12. Gene Tree Discordance Causes Apparent Substitution Rate Variation.

    Science.gov (United States)

    Mendes, Fábio K; Hahn, Matthew W

    2016-07-01

    Substitution rates are known to be variable among genes, chromosomes, species, and lineages due to multifarious biological processes. Here, we consider another source of substitution rate variation due to a technical bias associated with gene tree discordance. Discordance has been found to be rampant in genome-wide data sets, often due to incomplete lineage sorting (ILS). This apparent substitution rate variation is caused when substitutions that occur on discordant gene trees are analyzed in the context of a single, fixed species tree. Such substitutions have to be resolved by proposing multiple substitutions on the species tree, and we therefore refer to this phenomenon as Substitutions Produced by ILS (SPILS). We use simulations to demonstrate that SPILS has a larger effect with increasing levels of ILS, and on trees with larger numbers of taxa. Specific branches of the species trees are consistently, but erroneously, inferred to be longer or shorter, and we show that these branches can be predicted based on discordant tree topologies. Moreover, we observe that fixing a species tree topology when performing tests of positive selection increases the false positive rate, particularly for genes whose discordant topologies are most affected by SPILS. Finally, we use data from multiple Drosophila species to show that SPILS can be detected in nature. Although the effects of SPILS are modest per gene, it has the potential to affect substitution rate variation whenever high levels of ILS are present, particularly in rapid radiations. The problems outlined here have implications for character mapping of any type of trait, and for any biological process that causes discordance. We discuss possible solutions to these problems, and areas in which they are likely to have caused faulty inferences of convergence and accelerated evolution.

  13. Chromosome 19 International Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Pericak-Vance, M.A. (Duke Univ., Durham, NC (United States). Medical Center); Ropers, H.H. (Univ. Hospital Nijmegen, (The Netherlands). Dept. of Human Genetics); Carrano, A.J. (Lawrence Livermore National Lab., CA (United States))

    1993-01-04

    The Second International Workshop on Human Chromosome 19 was hosted on January 25 and 26, 1992, by the Department of Human Genetics, University Hospital Nijmegen, The Netherlands, at the 'Meerdal Conference Center'. The workshop was supported by a grant from the European Community obtained through HUGO, the Dutch Research Organization (NWO) and the Muscular Dystrophy Association (MDA). Travel support for American participants was provided by the Department of Energy. The goals of this workshop were to produce genetic, physical and integrated maps of chromosome 19, to identify inconsistencies and gaps, and to discuss and exchange resources and techniques available for the completion of these maps. The second day of the meeting was largely devoted to region or disease specific efforts. In particular, the meeting served as a platform for assessing and discussing the recent progress made into the molecular elucidation of myotonic dystrophy.

  14. [Dicentric Y chromosomes. First part: cytogenetic and molecular aspects].

    Science.gov (United States)

    Bouayed Abdelmoula, N; Amouri, A

    2005-01-01

    Dicentric Y chromosomes have been reviewed twice in 1994 by Hsu et al. and in 1995 by Tuck-Muller et al. who showed that dic(Y) are the most common Y structural abnormalities and that their influence on gonadal and somatic development is extremely variable. The prediction of their phenotypic consequences is often difficult because of the variety of genomic sequences concerned by duplications and deletions, because of the variable degrees of mosaicism (cell line 45,X in particular) and at the end, because of identification and analysis technical difficulties of the structure of the rearranged Y chromosome. The clinical specter of this cytogenetic abnormality is rather wide going from almost-normal or infertile males, to females with or without stigmas of Turner syndrome. Middle phenotypes consist of various degrees of genital ambiguities. However, clinical expression seems to be related to the genomic capital of the Y chromosome, mainly the Y genes involved in the control of the process of the determination of gonads (Yp) and spermatogenesis (Yq) as well as control of the growth and the skeletal development (Yp). Here, we report a third comprehensive review of the literature concerning dicentric Y chromosomes reported since 1994. In the light of previous reviews as well as the recent data of the genetic cartography of the Y chromosome, we try, in this first part, to determine characteristics of reported dicentric Y chromosomes as well as their chromosomal mechanics, their mitotic stability and finally their cytogenetic and molecular investigations.

  15. Increased recombinant protein production owing to expanded opportunities for vector integration in high chromosome number Chinese hamster ovary cells.

    Science.gov (United States)

    Yamano, Noriko; Takahashi, Mai; Ali Haghparast, Seyed Mohammad; Onitsuka, Masayoshi; Kumamoto, Toshitaka; Frank, Jana; Omasa, Takeshi

    2016-08-01

    Chromosomal instability is a characteristic of Chinese hamster ovary (CHO) cells. Cultures of these cells gradually develop heterogeneity even if established from a single cell clone. We isolated cells containing different numbers of chromosomes from a CHO-DG44-based human granulocyte-macrophage colony stimulating factor (hGM-CSF)-producing cell line and found that high chromosome number cells showed higher hGM-CSF productivity. Therefore, we focused on the relationship between chromosome aneuploidy of CHO cells and high recombinant protein-producing cell lines. Distribution and stability of chromosomes were examined in CHO-DG44 cells, and two cell lines expressing different numbers of chromosomes were isolated from the original CHO-DG44 cell line to investigate the effect of aneuploid cells on recombinant protein production. Both cell lines were stably transfected with a vector that expresses immunoglobulin G3 (IgG3), and specific antibody production rates were compared. Cells containing more than 30 chromosomes had higher specific antibody production rates than those with normal chromosome number. Single cell analysis of enhanced green fluorescent protein (Egfp)-gene transfected cells revealed that increased GFP expression was relative to the number of gene integration sites rather than the difference in chromosome numbers or vector locations. Our results suggest that CHO cells with high numbers of chromosomes contain more sites for vector integration, a characteristic that could be advantageous in biopharmaceutical production.

  16. Evolution of Dosage Compensation in Anolis carolinensis, a Reptile with XX/XY Chromosomal Sex Determination

    Science.gov (United States)

    Rupp, Shawn M.; Webster, Timothy H.; Olney, Kimberly C.; Hutchins, Elizabeth D.; Kusumi, Kenro

    2017-01-01

    In species with highly heteromorphic sex chromosomes, the degradation of one of the sex chromosomes will result in unequal gene expression between the sexes (e.g. between XX females and XY males) and between the sex chromosomes and the autosomes. Dosage compensation is a process whereby genes on the sex chromosomes achieve equal gene expression. We compared genome-wide levels of transcription between males and females, and between the X chromosome and the autosomes in the green anole, Anolis carolinensis. We present evidence for dosage compensation between the sexes, and between the sex chromosomes and the autosomes. When dividing the X chromosome into regions based on linkage groups, we discovered that genes in the first reported X-linked region, anole linkage group b (LGb), exhibit complete dosage compensation, although the rest of the X-linked genes exhibit incomplete dosage compensation. Our data further suggest that the mechanism of this dosage compensation is upregulation of the X chromosome in males. We report that approximately 10% of coding genes, most of which are on the autosomes, are differentially expressed between males and females. In addition, genes on the X chromosome exhibited higher ratios of nonsynonymous to synonymous substitution than autosomal genes, consistent with the fast-X effect. Our results from the green anole add an additional observation of dosage compensation in a species with XX/XY sex determination. PMID:28206607

  17. 小麦-簇毛麦染色体代换系、易位系Ⅴ染色体RAPD标记筛选%The Screening of RAPD Markers in V Chromosome of Wheat- haynaldia villosa Substitution Line and Translocation Lines

    Institute of Scientific and Technical Information of China (English)

    洪敬欣; 彭永康

    2004-01-01

    利用105条S系列和100条Operon随机引物,对小麦-簇毛麦代换系(6V/6A)、两个易位系(6VS/6AL,6VS/6DL)及亲本簇毛麦(VV)、硬粒小麦(AABB)、栽培小麦(AABBDD)的多态性进行了筛选分析.80.95%的S系列引物扩增出了结果,且条带较清晰;在100条OP系列引物中均扩增出结果,条带清晰可见.从205个随机引物中发现,只有1个引物OPW03在含有簇毛麦Ⅴ染色体的4个材料中均扩增出1条约570 bp的谱带,而在栽培小麦和硬粒小麦中没有发现.因此,可以推测这个分子标记(OPW03-570)是位于簇毛麦Ⅴ染色体短臂上的.

  18. 40 CFR 721.10034 - Substituted pyridine coupled with diazotized substituted nitrobenzonitrile, diazotized...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted pyridine coupled with... Specific Chemical Substances § 721.10034 Substituted pyridine coupled with diazotized substituted... as substituted pyridine coupled with diazotized substituted nitrobenzonitrile, diazotized...

  19. An open label randomized multicentre phase IIIb trial comparing parenteral substitution versus best supportive nutritional care in subjects with pancreatic adenocarcinoma receiving 5-FU plus oxaliplatin as 2nd or higher line chemotherapy regarding clinical benefit - PANUSCO

    Directory of Open Access Journals (Sweden)

    Rötzer Ingeborg

    2009-11-01

    Full Text Available Abstract Background Pancreatic cancer is an extremely aggressive malignancy. Subjects are afflicted with a variety of disconcerting symptoms, including profound cachexia. Recent data indicate that the outcome of oncological patients suffering from cancer cachexia could be improved by parenteral nutrition and that parenteral nutrition results in an improvement of quality of life and in prolonged survival. Currently, there is no recommendation of routine use of parenteral nutrition. Furthermore, there is no clear recommendation for 2nd line therapy (or higher for pancreatic adenocarcinoma but often asked for. Methods/Design PANUSCO is an open label, controlled, prospective, randomized, multicentre phase IIIb trial with two parallel arms. All patients will be treated with 5-fluorouracil, folinic acid and oxaliplatin on an outpatient basis at the study sites. Additionally, all patients will receive best supportive nutritional care (BSNC. In the experimental group BSNC will be expanded with parenteral nutrition (PN. In contrast, patients in the control group obtain solely BSNC. Parenteral nutrition will be applied overnight and at home by experienced medical staff. A total of 120 patients are planned to be enrolled. Primary endpoint is the comparison of the treatment groups with respect to event-free survival (EFS, defined as the time from randomization till time to development of an event defined as either an impairment (change from baseline of at least ten points in EORTC QLQ-C30, functional domain total score or withdrawal due to fulfilling the special defined stopping criteria for chemotherapy as well as for nutritional intervention (NI or death from any cause (whichever occurs first. Discussion The aim of this clinical trial is to evaluate whether parenteral nutrition in combination with defined 2nd line or higher chemotherapy has an impact on quality of life for patients suffering from pancreatic adenocarcinoma. Trial registration Current

  20. Development and Identification of Triticum aestivum L.-Thinopyrum bessarabicum L(o)ve Chromosome Translocations

    Institute of Scientific and Technical Information of China (English)

    ZHUANG Li-fang; QI Zeng-jun; CHEN Pei-du; FENG Yi-gao; LIU Da-jun

    2004-01-01

    With ass7istance of chromosome C-banding and genomic in situ hybridization(GISH)combined with meiotic analysis,five germplasms with homozygous wheat-Th. Bessarabicum chromosome translocations were developed and identified among BC1F5 progenies of the cross between T. Aestivum cv. Chinese Spring and Chinese Spring-Th. Bessarabicum amphiploid. These lines included Tj01 and Tj02(2n=44)containing a pair of wheat-Th. Bessarabicum translocation chromosomes besides a pair of added Th. Bessarabicum chromosomes,Tj03(2n=44)with a pair of added interspecific translocation chromosomes,Tj04(2n=44)containing a pair of interspecific translocation chromosomes besides an added pair of Th. Bessarabicum chromosome arms and Tj05(2n=46)containing a pair of interspecific translocation chromosomes besides two pairs of added intact alien chromosomes. The breakpoints of all the translocations were found to be not around centromere. Meanwhile,all the lines showed normal plant growth,development and fertility,while the translocation chromosomes transmitted regularly. The obtained translocations might be of use for transferring elite genes from Th. Bessarabicum into wheat.

  1. Knob-associated tandem repeats on mitotic chromosomes in maize, Zea diploperennis and their hybrids

    Institute of Scientific and Technical Information of China (English)

    XIONG Zhiyong; GAO Yuan; HE Guanyuan; GU Mingguang; GUO Lequn; SONG Yunchun

    2004-01-01

    Knob-associated tandem repeats, 180-bp repeats and TR-1 elements, together with 45S rDNA were located on mitotic chromosomes of Zea diploperennis (DP),maize inbred line F102 and their hybrid. In DP, knobs on the short arm of chromosomes 1 and 4 and on the long arm of the chromosomes 4 and 5 are composed predominantly of the 180-bp repeats. In addition, 180-bp repeats existed together with TR-1 elements were also detected on the short arm of chromosomes 2 and 5 and on the long arm of the chromosomes 2, 6, 7, 8 and 9. In maize inbred line F102, 180-bp repeats were present in chromosomes 7S and one homologue of chromosomes 8L. TR-1 elements appeared on satellite of chromosome 6 and no detectable hybridization site co-located with 180-bp repeats was observed in maize F102. Polymorphism of size, number, and distribution of 180-bp and TR-1 signals were revealed among different chromosomes in these two species and heteromorphism existed between some homologous chromosomes in the same species.Using these excellent landmarks, the interspecific hybrid of maize and DP were identified. The results suggest that comparative analysis of 180-bp repeats and TR-1 elements may help understand the genome organization and the evolution in Zea.

  2. Mössbauer studies of Sn4+/Nb5+ substituted Mn–Zn ferrites

    Indian Academy of Sciences (India)

    A D P Rao; S B Raju; S R Vadera; D R Sharma

    2003-08-01

    At room temperature, Mössbauer spectra of Sn4+/Nb5+ substituted Mn–Zn ferrites have been taken to understand the site occupancy of substituted ions. The results indicate that both the substituted ions occupy tetrahedral (A) site only at lower concentration of substitution while at higher concentration they occupy both tetrahedral and octahedral sites. At higher concentration of Nb substitution a doublet has been observed besides sextets. The possibility of canting existence on octahedral sites has been discussed. The observed variations of the hyperfine fields, isomer shift, line widths and B/A peak area ratio with the ferrite composition are interpreted.

  3. Y chromosome in Turner syndrome: review of the literature

    Directory of Open Access Journals (Sweden)

    Rose Mary Rocco de Oliveira

    Full Text Available Turner syndrome (TS is one of the most common types of aneuploidy among humans, and is present in 1:2000 newborns with female phenotype. Cytogenetically, the syndrome is characterized by sex chromosome monosomy (45,X, which is present in 50-60% of the cases. The other cases present mosaicism, with a 45,X cell line accompanied by one or more other cell lines with a complete or structurally abnormal X or Y chromosome. The presence of Y-chromosome material in patients with dysgenetic gonads increases the risk of gonadal tumors, especially gonadoblastoma. The greatest concern is the high risk of developing gonadoblastoma or other tumors and virilization during puberty if chromosome Y-specific sequences are present. The role of the Y chromosome in human oncogenesis is still controversial. Even though gonadoblastoma is a benign tumor, it can undergo transformation into invasive dysgerminoma in 60% of the cases, and also into other, malignant forms of germ cell tumors. Although some authors have questioned the high incidence of gonadoblastoma (around 30%, the risk of developing any kind of gonadal lesion, whether tumoral or not, justifies investigation of Y-chromosome sequences by means of the polymerase chain reaction (PCR, a highly sensitive, low-cost and easy-to-perform technique. In conclusion, mosaicism of both the X and the Y chromosome is a common finding in TS, and detection of Y-chromosome-specific sequences in patients, regardless of their karyotype, is necessary in order to prevent the development of gonadal lesions.

  4. Development of EST-PCR Markers for the Chromosome 4VofHaynaldia villosaand Their Application in Identification of 4V Chromosome Structural Aberrants

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ren-hui; WANG Hai-yan; JIA Qi; XIAO Jin; YUAN Chun-xia; ZHANG Ya-jun; HU Qing-shan; WANG Xiu-e

    2014-01-01

    EST-PCR based molecular markers speciifc for alien chromosomes are not only useful for the detection of the introgressed alien chromatin in the wheat background, but also provide evidence of the syntenic relationship between homoeologous chromosomes. In the present study, in order to develop high density and evenly distributed molecular markers on chromosome 4V ofHaynaldia villosa, a total of 607 primer pairs were designed according to the EST sequences, which were previously located in 23 different bins of wheat chromosomes 4A, 4B and 4D. By using theTriticum durum-H. villosaamphiploid and T. aestivum-H. villosa alien chromosome lines involving chromosome 4V, it was found that 9.23% of the tested primers could amplify speciifc bands for chromosome 4V. Thirty and twenty-six speciifc markers could be assigned to chromosome arms 4VS and 4VL, respectively. These 4V speciifc markers provided efifcient tools for the characterization of structural variation involving the chromosome 4V as well as for the selection of useful genes located on chromosome 4V in breeding programs.

  5. Chromosomal and behavioral studies of Mexican Drosophila. III. Inversion polymorphism of D. pseudoobscura.

    Science.gov (United States)

    Olvera, O; Rockwell, R F; de la Rosa, M E; Gaso, M I; Gonzalez, F; Guzman, J; Levine, L

    1985-01-01

    Four new gene arrangements of chromosome 3 of Drosophila pseudoobscura are reported, as well as an updated phylogenetic sequence of the inversion polymorphism in this species. Evidence that the Tree Line gene arrangement of chromosome 3 was the original form in D. pseudoobscura, and that Central Mexico is the center of distribution of this species is discussed.

  6. Progress towards construction of a total restriction fragment map of a human chromosome.

    NARCIS (Netherlands)

    H. Vissing; F.G. Grosveld (Frank); E. Solomon; G. Moore; N. Lench; N. Shennan; R. Williamson

    1987-01-01

    textabstractWe present an approach to the construction of an overlapping restriction fragment map of a single human chromosome. A genomic cosmid library genome was constructed from a mouse-human hybrid cell line containing chromosome 17 as its only human genetic component. Cosmids containing human i

  7. Localization to Chromosomes of Structural Genes for the Major Protease Inhibitors of Barley Grains

    DEFF Research Database (Denmark)

    Hejgaard, Jørn; Bjørn, S.E.; Nielsen, Gunnar Gissel

    1984-01-01

    Wheat-barley chromosome addition lines were compared by isoelectric focusing of protein extracts to identify chromosomes carrying loci for the major immunochemically distinct protease inhibitors of barley grains. Structural genes for the following inhibitors were localized: an inhibitor of both...

  8. Effects of heavy-ion beams on chromosomes of common wheat, Triticum aestivum

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Shinji; Saito, Yoshinaka [Laboratory of Plant Genetics and Breeding Science, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori 680-8553 (Japan); Ryuto, Hiromichi; Fukunishi, Nobuhisa; Abe, Tomoko [RIKEN Nishina Center, RIKEN, Hirosawa, Wako 351-0198 (Japan); Tanaka, Hiroyuki [Laboratory of Plant Genetics and Breeding Science, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori 680-8553 (Japan); Tsujimoto, Hisashi, E-mail: tsujim@muses.tottori-u.ac.jp [Laboratory of Plant Genetics and Breeding Science, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori 680-8553 (Japan)

    2009-10-02

    To investigate the nature of plant chromosomes irradiated by heavy-ion beams, the effects of nitrogen (N) and neon (Ne) ion beams on hexaploid wheat chromosomes were compared with those of X-ray. Chromosome aberrations, such as short, ring and dicentric chromosomes appeared in high frequency. The average numbers of chromosome breaks at LD-50 by irradiation with X-ray, N and Ne ion beams were 32, 20 and 20, respectively. These values may be underestimated because chromosome rearrangement without change in chromosome morphology was not counted. Thus, we subsequently used a wheat line with a pair of extra chromosomes from an alien species (Leymus racemosus) and observed the fate of the irradiated marker chromosomes by genomic in situ hybridization. This analysis revealed that 50 Gy of neon beam induced about eight times more breaks than those induced by X-ray. This result suggests that heavy-ion beams induce chromosome rearrangement in high frequency rather than loss of gene function. This suggests further that most of the novel mutations produced by ion beam irradiation, which have been used in plant breeding, may not be caused by ordinary gene disruption but by chromosome rearrangements.

  9. Intraspecific chromosome variability

    Directory of Open Access Journals (Sweden)

    N Dubinin

    2010-12-01

    Full Text Available (Editorial preface. The publication is presented in order to remind us of one of dramatic pages of the history of genetics. It re-opens for the contemporary reader a comprehensive work marking the priority change from plant cytogenetics to animal cytogenetics led by wide population studies which were conducted on Drosophila polytene chromosomes. The year of the publication (1937 became the point of irretrievable branching between the directions of Old World and New World genetics connected with the problems of chromosome variability and its significance for the evolution of the species. The famous book of T. Dobzhansky (1937 was published by Columbia University in the US under the title “Genetics and the origin of species”, and in the shadow of this American ‘skybuilding’ all other works grew dim. It is remarkable that both Dobzhansky and Dubinin come to similar conclusions about the role of chromosomes in speciation. This is not surprising given that they both might be considered as representatives of the Russian genetic school, by their birth and education. Interestingly, Dobzhansky had never referred to the full paper of Dubinin et al. (1937, though a previous short communication in Nature (1936 was included together with all former papers on the related subject. In full, the volume of the original publication printed in the Biological Journal in Moscow comprised 47 pages, in that number 41 pages of the Russian text accompanied by 16 Figs, a table and reference list, and, above all, 6 pages of the English summary. This final part in English is now reproduced in the authors’ version with the only addition being the reference list in the originally printed form.

  10. Chromosome assortment in Saccharum.

    Science.gov (United States)

    Al-Janabi, S M; Honeycutt, R J; Sobral, B W

    1994-12-01

    Recent work has revealed random chromosome pairing and assortment in Saccharum spontaneum L., the most widely distributed, and morphologically and cytologically variable of the species of Saccharum. This conclusion was based on the analysis of a segregating population from across between S. spontaneum 'SES 208' and a spontaneously-doubled haploid of itself, derived from anther culture. To determine whether polysomic inheritance is common in Saccharum and whether it is observed in a typical biparental cross, we studied chromosome pairing and assortment in 44 progeny of a cross between euploid, meiotically regular, 2n=80 forms of Saccharum officinarum 'LA Purple' and Saccharum robustum ' Mol 5829'. Papuan 2n=80 forms of S. robustum have been suggested as the immediate progenitor species for cultivated sugarcane (S. officinarum). A total of 738 loci in LA Purple and 720 loci in Mol 5829 were amplified and typed in the progeny by arbitrarily primed PCR using 45 primers. Fifty and 33 single-dose polymorphisms were identified in the S. officinarum and S. robustum genomes, respectively (χ 2 at 98%). Linkage analysis of single-dose polymorphisms in both genomes revealed linkages in repulsion and coupling phases. In the S. officinarum genome, a map hypothesis gave 7 linkage groups with 17 linked and 33 unlinked markers. Four of 13 pairwise linkages were in repulsion phase and 9 were in coupling phase. In the S. robustum genome, a map hypothesis gave 5 linkage groups, defined by 12 markers, with 21 markers unlinked, and 2 of 9 pairwise linkages were in repulsion phase. Therefore, complete polysomic inheritance was not observed in either species, suggesting that chromosomal behavior is different from that observed by linkage analysis of over 500 markers in the S. spontaneum map. Implications of this finding for evolution and breeding are discussed.

  11. Independent intrachromosomal recombination events underlie the pericentric inversions of chimpanzee and gorilla chromosomes homologous to human chromosome 16.

    Science.gov (United States)

    Goidts, Violaine; Szamalek, Justyna M; de Jong, Pieter J; Cooper, David N; Chuzhanova, Nadia; Hameister, Horst; Kehrer-Sawatzki, Hildegard

    2005-09-01

    Analyses of chromosomal rearrangements that have occurred during the evolution of the hominoids can reveal much about the mutational mechanisms underlying primate chromosome evolution. We characterized the breakpoints of the pericentric inversion of chimpanzee chromosome 18 (PTR XVI), which is homologous to human chromosome 16 (HSA 16). A conserved 23-kb inverted repeat composed of satellites, LINE and Alu elements was identified near the breakpoints and could have mediated the inversion by bringing the chromosomal arms into close proximity with each other, thereby facilitating intrachromosomal recombination. The exact positions of the breakpoints may then have been determined by local DNA sequence homologies between the inversion breakpoints, including a 22-base pair direct repeat. The similarly located pericentric inversion of gorilla (GGO) chromosome XVI, was studied by FISH and PCR analysis. The p- and q-arm breakpoints of the inversions in PTR XVI and GGO XVI were found to occur at slightly different locations, consistent with their independent origin. Further, FISH studies of the homologous chromosomal regions in macaque and orangutan revealed that the region represented by HSA BAC RP11-696P19, which spans the inversion breakpoint on HSA 16q11-12, was derived from the ancestral primate chromosome homologous to HSA 1. After the divergence of orangutan from the other great apes approximately 12 million years ago (Mya), a duplication of the corresponding region occurred followed by its interchromosomal transposition to the ancestral chromosome 16q. Thus, the most parsimonious interpretation is that the gorilla and chimpanzee homologs exhibit similar but nonidentical derived pericentric inversions, whereas HSA 16 represents the ancestral form among hominoids.

  12. Dissecting plant chromosomes by the use of ionizing radiation

    Science.gov (United States)

    Radiation treatment of genomes is used to generate chromosome breaks for numerous applications. This protocol describes the preparation of seeds and the determination of the optimal level of irradiation dosage for the creation of a radiation hybrid (RH) population. These RH lines can be used to gene...

  13. Chromosome Connections: Compelling Clues to Common Ancestry

    Science.gov (United States)

    Flammer, Larry

    2013-01-01

    Students compare banding patterns on hominid chromosomes and see striking evidence of their common ancestry. To test this, human chromosome no. 2 is matched with two shorter chimpanzee chromosomes, leading to the hypothesis that human chromosome 2 resulted from the fusion of the two shorter chromosomes. Students test that hypothesis by looking for…

  14. Chromosomal rearrangement interferes with meiotic X chromosome inactivation.

    Science.gov (United States)

    Homolka, David; Ivanek, Robert; Capkova, Jana; Jansa, Petr; Forejt, Jiri

    2007-10-01

    Heterozygosity for certain mouse and human chromosomal rearrangements is characterized by the incomplete meiotic synapsis of rearranged chromosomes, by their colocalization with the XY body in primary spermatocytes, and by male-limited sterility. Previously, we argued that such X-autosomal associations could interfere with meiotic sex chromosome inactivation. Recently, supporting evidence has reported modifications of histones in rearranged chromosomes by a process called the meiotic silencing of unsynapsed chromatin (MSUC). Here, we report on the transcriptional down-regulation of genes within the unsynapsed region of the rearranged mouse chromosome 17, and on the subsequent disturbance of X chromosome inactivation. The partial transcriptional suppression of genes in the unsynapsed chromatin was most prominent prior to the mid-pachytene stage of primary spermatocytes. Later, during the mid-late pachytene, the rearranged autosomes colocalized with the XY body, and the X chromosome failed to undergo proper transcriptional silencing. Our findings provide direct evidence on the MSUC acting at the mRNA level, and implicate that autosomal asynapsis in meiosis may cause male sterility by interfering with meiotic sex chromosome inactivation.

  15. Chromosomal imbalances revealed in primary rhabdomyosarcomas by comparative genomic hybridization

    Institute of Scientific and Technical Information of China (English)

    LI Qiao-xin; LIU Chun-xia; CHUN Cai-pu; QI Yan; CHANG Bin; LI Xin-xia; CHEN Yun-zhao; NONG Wei-xia; LI Hong-an; LI Feng

    2009-01-01

    Background Previous cytogenetic studies revealed aberrations varied among the throe subtypes of rhabdomyosarcoma. We profiled chromosomal imbalances in the different subtypes and investigated the relationships between clinical parameters and genomic aberrations.Methods Comparative genomic hybridization was used to investigate genomic imbalances in 25 cases of primary rhabdomyosarcomas and two rhabdomyosarcoma cell lines. Specimens were reviewed to determine histological type, pathological grading and clinical staging.Results Changes involving one or more regions of the genome were seen in all rhabdomyosarcomal patients. For rhabdomyosarcoma, DNA sequence gains were most frequently (>30%) seen in chromosomes 2p, 12q, 6p, 9q, 10q, 1p,2q, 6q, 8q, 15q and 18q; losses from 3p, 11p and 6p. In aggressive alveolar rhabdomyosarcoma, frequent gains were seen on chromosomes 12q, 2p, 6p, 2q, 4q, 10q and 15q; losses from 3p, 6p, 1q and 5q. For embryonic rhabdomyosarcoma, frequent gains were on 7p, 9q, 2p, 18q, 1p and 8q; losses only from 11p. Frequently gained chromosome arms of translocation associated with rhabdomyosarcoma were 12q, 2, 6, 10q, 4q and 15q; losses from 3p,6p and 5q. The frequently gained chromosome arms of nontranslocation associated with rhabdomyosarcoma were 2p,9q and 18q, while 11p and 14q were the frequently lost chromosome arms. Gains on chromosome 12q were significantly correlated with translocation type. Gains on chromosome 9q were significantly correlated with clinical staging. Conclusions Gains on chromosomes 2p, 12q, 6p, 9q, 10q, 1p, 2q, 6q, 8q, 15q and 18q and losses on chromosomes 3p, 11p and 6p may be related to rhabdomyosarcomal carcinogenesis. Furthermore, gains on chromosome 12q may be correlated with translocation and gains on chromosome 9q with the early stages of rhabdomyosarcoma.

  16. Chromosomal Location of the Genes Associated with Photosynthesis of Lophopyrum elongatum (Host) A. L(o)ve in Chinese Spring Background

    Institute of Scientific and Technical Information of China (English)

    PENG Yuan-ying; PENG Zheng-song; SONG Hui-xing; XU Jia-shao

    2006-01-01

    Researches on the relationship between photosynthesis and wheat yield have equally attracted the attention of both domestic and overseas scholars. No report has existed so far on the study of the effects of exogenous chromosomes on photosynthesis using the substitution series as materials. In this research, Triticum aestivum cv. Chinese Spring-Lophopyrum elongatum (Host) A.L(o)ve disomic substitution series were used as materials and flag leaves as the measuring position. And the CI-310 Portable Photosynthesis System made by CID Co. in USA was used to measure the net rate of photosynthesis of flag leaves in different developing stages and also to correlate photosynthesis with yield. Results showed that, out of the whole developing stages, at the anthesis stage the line of DS2Ee (2A) had the highest photosynthetic rate, therefore it could be used in improving process of the character of kernel number. The flag leaves of DS4Ee (4A, 4B, 4D) lines demonstrated certain high net photosynthetic rate from heading to grain filling stage, so it is valuable in the researh of promoting the yield index like 1000-grain weight through improvement of the photosynthetic rate at grain filling stage.

  17. Chromosomal abnormalities in patients with autism spectrum disorders from Taiwan.

    Science.gov (United States)

    Liao, Hsiao-Mei; Gau, Susan Shur-Fen; Tsai, Wen-Che; Fang, Jye-Siung; Su, Ying-Cheng; Chou, Miao-Chun; Liu, Shih-Kai; Chou, Wen-Jiun; Wu, Yu-Yu; Chen, Chia-Hsiang

    2013-10-01

    Autism spectrum disorders (ASD) are childhood-onset neurodevelopmental disorders characterized by verbal communication impairments, social reciprocity deficits, and the presence of restricted interests and stereotyped behaviors. Genetic factors contribute to the incidence of ASD evidently. However, the genetic spectrum of ASD is highly heterogeneous. Chromosomal abnormalities contribute significantly to the genetic deficits of syndromic and non-syndromic ASD. In this study, we conducted karyotyping analysis in a sample of 500 patients (447 males, 53 females) with ASD from Taiwan, the largest cohort in Asia, to the best of our knowledge. We found three patients having sex chromosome aneuploidy, including two cases of 47, XXY and one case of 47, XYY. In addition, we detected a novel reciprocal chromosomal translocation between long arms of chromosomes 4 and 14, designated t(4;14)(q31.3;q24.1), in a patient with Asperger's disorder. This translocation was inherited from his unaffected father, suggesting it might not be pathogenic or it needs further hits to become pathogenic. In line with other studies, our study revealed that subjects with sex chromosomal aneuploidy are liable to neurodevelopmental disorders, including ASD, and conventional karyotyping analysis is still a useful tool in detecting chromosomal translocation in patients with ASD, given that array-based comparative genomic hybridization technology can provide better resolution in detecting copy number variations of genomic DNA.

  18. RNAi pathway participates in chromosome segregation in mammalian cells.

    Science.gov (United States)

    Huang, Chuan; Wang, Xiaolin; Liu, Xu; Cao, Shuhuan; Shan, Ge

    2015-01-01

    The RNAi machinery is a mighty regulator in a myriad of life events. Despite lines of evidence that small RNAs and components of the RNAi pathway may be associated with structure and behavior of mitotic chromosomes in diverse organisms, a direct role of the RNAi pathway in mammalian mitotic chromosome segregation remains elusive. Here we report that Dicer and AGO2, two central components of the mammalian RNAi pathway, participate in the chromosome segregation. Knockdown of Dicer or AGO2 results in a higher incidence of chromosome lagging, and this effect is independent from microRNAs as examined with DGCR8 knockout cells. Further investigation has revealed that α-satellite RNA, a noncoding RNA derived from centromeric repeat region, is managed by AGO2 under the guidance of endogenous small interference RNAs (ASAT siRNAs) generated by Dicer. Furthermore, the slicer activity of AGO2 is essential for the chromosome segregation. Level and distribution of chromosome-associated α-satellite RNA have crucial regulatory effect on the localization of centromeric proteins such as centromere protein C1 (CENPC1). With these results, we also provide a paradigm in which the RNAi pathway participates in vital cellular events through the maintenance of level and distribution of noncoding RNAs in cells.

  19. Chromosomal abnormalities, meiotic behavior and fertility in domestic animals.

    Science.gov (United States)

    Villagómez, D A F; Pinton, A

    2008-01-01

    Since the advent of the surface microspreading technique for synaptonemal complex analysis, increasing interest in describing the synapsis patterns of chromosome abnormalities associated with fertility of domestic animals has been noticed during the past three decades. In spite of the number of scientific reports describing the occurrence of structural chromosome abnormalities, their meiotic behavior and gametic products, little is known in domestic animal species about the functional effects of such chromosome aberrations in the germ cell line of carriers. However, some interesting facts gained from recent and previous studies on the meiotic behavior of chromosome abnormalities of domestic animals permit us to discuss, in the frame of recent knowledge emerging from mouse and human investigations, the possible mechanism implicated in the well known association between meiotic disruption and chromosome pairing failure. New cytogenetic techniques, based on molecular and immunofluorescent analyses, are allowing a better description of meiotic processes, including gamete production. The present communication reviews the knowledge of the meiotic consequences of chromosome abnormalities in domestic animals.

  20. Cohesin in determining chromosome architecture

    Energy Technology Data Exchange (ETDEWEB)

    Haering, Christian H., E-mail: christian.haering@embl.de [Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg (Germany); Jessberger, Rolf, E-mail: rolf.jessberger@tu-dresden.de [Institute of Physiological Chemistry, Dresden University of Technology, Dresden (Germany)

    2012-07-15

    Cells use ring-like structured protein complexes for various tasks in DNA dynamics. The tripartite cohesin ring is particularly suited to determine chromosome architecture, for it is large and dynamic, may acquire different forms, and is involved in several distinct nuclear processes. This review focuses on cohesin's role in structuring chromosomes during mitotic and meiotic cell divisions and during interphase.

  1. Displacement, Substitution, Sublimation: A Bibliography.

    Science.gov (United States)

    Pedrini, D. T.; Pedrini, Bonnie C.

    Sigmund Freund worked with the mechanisms of displacement, substitution, and sublimation. These mechanisms have many similarities and have been studied diagnostically and therapeutically. Displacement and substitution seem to fit in well with phobias, hysterias, somatiyations, prejudices, and scapegoating. Phobias, prejudices, and scapegoating…

  2. Currency substitution in Eastern Europe

    NARCIS (Netherlands)

    van Aarle, B.; Budina, N.

    1995-01-01

    Monetary instability during the transition process from a command economy to a market economy has induced a considerable increase in currency substitution in Eastern Europe. Currency substitution itself affects monetary stability since it reduces the stability of velocity. This paper investigates cu

  3. Formation of complex and unstable chromosomal translocations in yeast.

    Directory of Open Access Journals (Sweden)

    Kristina H Schmidt

    Full Text Available Genome instability, associated with chromosome breakage syndromes and most human cancers, is still poorly understood. In the yeast Saccharomyces cerevisiae, numerous genes with roles in the preservation of genome integrity have been identified. DNA-damage-checkpoint-deficient yeast cells that lack Sgs1, a RecQ-like DNA helicase related to the human Bloom's-syndrome-associated helicase BLM, show an increased rate of genome instability, and we have previously shown that they accumulate recurring chromosomal translocations between three similar genes, CAN1, LYP1 and ALP1. Here, the chromosomal location, copy number and sequence similarity of the translocation targets ALP1 and LYP1 were altered to gain insight into the formation of complex translocations. Among 844 clones with chromosomal rearrangements, 93 with various types of simple and complex translocations involving CAN1, LYP1 and ALP1 were identified. Breakpoint sequencing and mapping showed that the formation of complex translocation types is strictly dependent on the location of the initiating DNA break and revealed that complex translocations arise via a combination of interchromosomal translocation and template-switching, as well as from unstable dicentric intermediates. Template-switching occurred between sequences on the same chromosome, but was inhibited if the genes were transferred to different chromosomes. Unstable dicentric translocations continuously gave rise to clones with multiple translocations in various combinations, reminiscent of intratumor heterogeneity in human cancers. Base substitutions and evidence of DNA slippage near rearrangement breakpoints revealed that translocation formation can be accompanied by point mutations, and their presence in different translocation types within the same clone provides evidence that some of the different translocation types are derived from each other rather than being formed de novo. These findings provide insight into eukaryotic

  4. Mixed gonadal dysgenesis in a 45,X neonate with chromosome Y material in the dysgenetic gonad.

    Science.gov (United States)

    Karatza, Ageliki; Chrysis, Dionisios; Stefanou, Eunice-Georgia; Mantagos, Stefanos; Salakos, Christos

    2009-11-01

    We report on a neonate with a disorder of sex development, Prader 3-4 external genitalia and a palpable structure in the right inguinal canal suggestive of gonadal tissue. Chromosome studies on blood lymphocytes showed monosomy of chromosome X. Laparoscopy identified a streak-like gonad on the left side, unicorn uterus and a dysgenetic testis on the right, attached to a Fallopian tube. Because of the unilateral palpable gonad and the presence of ambiguous genitalia we investigated further for the presence of Y material. Quantitative fluorescent PCR analysis of material from the dysgenetic gonad and skin fibroblasts revealed the presence of chromosome Y-derived sequences, suggesting sex chromosome mosaicism. In 45,X/46,XY mosaicism, chromosome studies carried out on peripheral lymphocytes do not always reflect the proportion of cell lines in the gonads. The detection of Y chromosome material in a dysgenetic gonad is extremely significant, due to the high risk of malignant transformation.

  5. Genetics Home Reference: Y chromosome infertility

    Science.gov (United States)

    ... Home Health Conditions Y chromosome infertility Y chromosome infertility Enable Javascript to view the expand/collapse boxes. ... PDF Open All Close All Description Y chromosome infertility is a condition that affects the production of ...

  6. Higher order structure of chromosomes.

    Science.gov (United States)

    Okada, T A; Comings, D E

    1979-04-01

    Isolated Chinese hamster metaphase chromosomes were resuspended in 4 M ammonium acetate and spread on a surface of distilled water or 0.15 to 0.5 M ammonium acetate. The DNA was released in the form of a regular series of rosettes connected by interrossette DNA. The mean length of the rosette DNA was 14 micron, similar to the mean length of 10 micron for chromomere DNA of Drosophila polytene chromosomes. The mean interrosette DNA was 4.2 micron. SDS gel electrophoresis of the chromosomal nonhistone proteins showed them to be very similar to nuclear nonhistone proteins except for the presence of more actin and tubulin. Nuclear matrix proteins were present in the chromosomes and may play a role in forming the rosettes. Evidence that the rosette pattern is artifactual versus the possibility that it represents a real organizational substructure of the chromosomes is reviewed.

  7. Bacterial chromosome organization and segregation.

    Science.gov (United States)

    Badrinarayanan, Anjana; Le, Tung B K; Laub, Michael T

    2015-01-01

    If fully stretched out, a typical bacterial chromosome would be nearly 1 mm long, approximately 1,000 times the length of a cell. Not only must cells massively compact their genetic material, but they must also organize their DNA in a manner that is compatible with a range of cellular processes, including DNA replication, DNA repair, homologous recombination, and horizontal gene transfer. Recent work, driven in part by technological advances, has begun to reveal the general principles of chromosome organization in bacteria. Here, drawing on studies of many different organisms, we review the emerging picture of how bacterial chromosomes are structured at multiple length scales, highlighting the functions of various DNA-binding proteins and the impact of physical forces. Additionally, we discuss the spatial dynamics of chromosomes, particularly during their segregation to daughter cells. Although there has been tremendous progress, we also highlight gaps that remain in understanding chromosome organization and segregation.

  8. Chromosome choreography: the meiotic ballet.

    Science.gov (United States)

    Page, Scott L; Hawley, R Scott

    2003-08-08

    The separation of homologous chromosomes during meiosis in eukaryotes is the physical basis of Mendelian inheritance. The core of the meiotic process is a specialized nuclear division (meiosis I) in which homologs pair with each other, recombine, and then segregate from each other. The processes of chromosome alignment and pairing allow for homolog recognition. Reciprocal meiotic recombination ensures meiotic chromosome segregation by converting sister chromatid cohesion into mechanisms that hold homologous chromosomes together. Finally, the ability of sister kinetochores to orient to a single pole at metaphase I allows the separation of homologs to two different daughter cells. Failures to properly accomplish this elegant chromosome dance result in aneuploidy, a major cause of miscarriage and birth defects in human beings.

  9. Schizophrenia and chromosomal deletions

    Energy Technology Data Exchange (ETDEWEB)

    Lindsay, E.A.; Baldini, A. [Baylor College of Medicine, Houston, TX (United States); Morris, M. A. [Univ. of Geneva School of Medicine, NY (United States)] [and others

    1995-06-01

    Recent genetic linkage analysis studies have suggested the presence of a schizophrenia locus on the chromosomal region 22q11-q13. Schizophrenia has also been frequently observed in patients affected with velo-cardio-facial syndrome (VCFS), a disorder frequently associated with deletions within 22q11.1. It has been hypothesized that psychosis in VCFS may be due to deletion of the catechol-o-methyl transferase gene. Prompted by these observations, we screened for 22q11 deletions in a population of 100 schizophrenics selected from the Maryland Epidemiological Sample. Our results show that there are schizophrenic patients carrying a deletion of 22q11.1 and a mild VCFS phenotype that might remain unrecognized. These findings should encourage a search for a schizophrenia-susceptibility gene within the deleted region and alert those in clinical practice to the possible presence of a mild VCFS phenotype associated with schizophrenia. 9 refs.

  10. Identification of chromosome abnormalities in the horse using a panel of chromosome-specific painting probes generated by microdissection.

    Science.gov (United States)

    Bugno, Monika; Słota, Ewa; Pieńkowska-Schelling, Aldona; Schelling, Claude

    2009-09-01

    Fluorescent in situ hybridisation (FISH) using a panel of molecular probes for all chromosome pairs obtained by chromosome microdissection of the domestic horse ( Equus caballus ) was used to diagnose karyotype abnormalities in 35 horses (32 mares, 2 stallions and 1 intersex), which were selected for the study due to infertility (23 horses), reduced fertility (10 horses) and developmental anomalies (2 horses). The use of the FISH technique with probes for each horse chromosome pair enabled the diagnosis of many different chromosome aberrations in this population. Among the horses analysed, 21 animals had normal karyotype - 64,XX (19 mares) and 64,XY (2 stallions). Fourteen animals, constituting 40% of the population studied, showed the following chromosome abnormalities: 63,X (1 mare); 63,X/64,XX (6 mares); 63,X/64,XX/65,XXX (3 mares); 63,X/65,XXX (1 mare); 64,XX/65,XX+Xp (1 mare); 63,X/64,XX/65,XX+Xq (1 mare), and 63,X/64,XX/65,XX+delY (1 intersex). When only the mares studied because of complete infertility were taken into consideration, this proportion exceeded 56%. Due to the increased frequency of the above-mentioned aberrations in the mosaic form of two or more lines, it was necessary to analyse a large number (100-300) of metaphase spreads. The use of specific molecular probes obtained by chromosome microdissection made these diagnoses much easier.

  11. Chromosome copy number variation and control in the ciliate Chilodonella uncinata.

    Directory of Open Access Journals (Sweden)

    Kevin J Spring

    Full Text Available Copy number variations are widespread in eukaryotes. The unusual genome architecture of ciliates, in particular, with its process of amitosis in macronuclear division, provides a valuable model in which to study copy number variation. The current model of amitosis envisions stochastic distribution of macronuclear chromosomes during asexual reproduction. This suggests that amitosis is likely to result in high levels of copy number variation in ciliates, as dividing daughter cells can have variable copy numbers of chromosomes if chromosomal distribution during amitosis is a stochastic process. We examined chromosomal distribution during amitosis in Chilodonella uncinata, a ciliate with gene-size macronuclear chromosomes. We quantified 4 chromosomes in evolving populations of C. uncinata and modeled the amitotic distribution process. We found that macronuclear chromosomes differ in copy number from one another but that copy number does not change as expected under a stochastic process. The chromosome carrying SSU increased in copy number, which is consistent with selection to increase abundance; however, two other studied chromosomes displayed much lower than expected among-line variance. Our models suggest that balancing selection is sufficient to explain the observed maintenance of chromosome copy during asexual reproduction.

  12. The TP53 dependence of radiation-induced chromosome instability in human lymphoblastoid cells

    Science.gov (United States)

    Schwartz, Jeffrey L.; Jordan, Robert; Evans, Helen H.; Lenarczyk, Marek; Liber, Howard

    2003-01-01

    The dose and TP53 dependence for the induction of chromosome instability were examined in cells of three human lymphoblastoid cell lines derived from WIL2 cells: TK6, a TP53-normal cell line, NH32, a TP53-knockout created from TK6, and WTK1, a WIL2-derived cell line that spontaneously developed a TP53 mutation. Cells of each cell line were exposed to (137)Cs gamma rays, and then surviving clones were isolated and expanded in culture for approximately 35 generations before the frequency and characteristics of the instability were analyzed. The presence of dicentric chromosomes, formed by end-to-end fusions, served as a marker of chromosomal instability. Unexposed TK6 cells had low levels of chromosomal instability (0.002 +/- 0.001 dicentrics/cell). Exposure of TK6 cells to doses as low as 5 cGy gamma rays increased chromosome instability levels nearly 10-fold to 0.019 +/- 0.008 dicentrics/cell. There was no further increase in instability levels beyond 5 cGy. In contrast to TK6 cells, unexposed cultures of WTK1 and NH32 cells had much higher levels of chromosome instability of 0.034 +/- 0.007 and 0.041 +/- 0.009, respectively, but showed little if any effect of radiation on levels of chromosome instability. The results suggest that radiation exposure alters the normal TP53-dependent cell cycle checkpoint controls that recognize alterations in telomere structure and activate apoptosis.

  13. Trifluoromethyl-substituted tetrathiafulvalenes

    Directory of Open Access Journals (Sweden)

    Olivier Jeannin

    2015-05-01

    Full Text Available A series of tetrathiafulvalenes functionalized with one or two trifluoromethyl electron-withdrawing groups (EWG is obtained by phosphite coupling involving CF3-substituted 1,3-dithiole-2-one derivatives. The relative effects of the EWG such as CF3, CO2Me and CN on the TTF core were investigated from a combination of structural, electrochemical, spectrochemical and theoretical investigations. Electrochemical data confirm the good correlations between the first oxidation potential of the TTF derivatives and the σmeta Hammet parameter, thus in the order CO2Me 3 3, where, as in TTF itself, the low energy absorption band is essentially attributable to a HOMO→LUMO + 1 transition. Despite relatively high oxidation potentials, these donor molecules with CF3 EWG can be involved in charge transfer complexes or cation radical salts, as reported here for the CF3-subsituted EDT-TTF donor molecule. A neutral charge transfer complex with TCNQ, (EDT-TTF-CF32(TCNQ was isolated and characterized through alternated stacks of EDT-TTF-CF3 dimers and TCNQ in the solid state. A radical cation salt of EDT-TTF-CF3 is also obtained upon electrocrystallisation in the presence of the FeCl4− anion. In this salt, formulated as (EDT-TTF-CF3(FeCl4, the (EDT-TTF-CF3+• radical cations are associated two-by-two into centrosymmetric dyads with a strong pairing of the radical species in a singlet state.

  14. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose the continued development of a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and...

  15. CHROMOSOMAL MAPPING IN STRAINS OF STAPHYLOCOCCUS AUREUS,

    Science.gov (United States)

    STAPHYLOCOCCUS AUREUS , CHROMOSOMES), (*CHROMOSOMES, MAPPING), NITROSO COMPOUNDS, GUANIDINES, GENETICS, MUTATIONS, DRUGS, TOLERANCES(PHYSIOLOGY), TEST METHODS, DEOXYRIBONUCLEIC ACIDS, INHIBITION, RESISTANCE(BIOLOGY).

  16. Chromatid Painting for Chromosomal Inversion Detection Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a novel approach to the detection of chromosomal inversions. Transmissible chromosome aberrations (translocations and inversions) have profound genetic...

  17. Mitotic chromosome condensation in vertebrates

    Energy Technology Data Exchange (ETDEWEB)

    Vagnarelli, Paola, E-mail: P.Vagnarelli@ed.ac.uk

    2012-07-15

    Work from several laboratories over the past 10-15 years has revealed that, within the interphase nucleus, chromosomes are organized into spatially distinct territories [T. Cremer, C. Cremer, Chromosome territories, nuclear architecture and gene regulation in mammalian cells, Nat. Rev. Genet. 2 (2001) 292-301 and T. Cremer, M. Cremer, S. Dietzel, S. Muller, I. Solovei, S. Fakan, Chromosome territories-a functional nuclear landscape, Curr. Opin. Cell Biol. 18 (2006) 307-316]. The overall compaction level and intranuclear location varies as a function of gene density for both entire chromosomes [J.A. Croft, J.M. Bridger, S. Boyle, P. Perry, P. Teague,W.A. Bickmore, Differences in the localization and morphology of chromosomes in the human nucleus, J. Cell Biol. 145 (1999) 1119-1131] and specific chromosomal regions [N.L. Mahy, P.E. Perry, S. Gilchrist, R.A. Baldock, W.A. Bickmore, Spatial organization of active and inactive genes and noncoding DNA within chromosome territories, J. Cell Biol. 157 (2002) 579-589] (Fig. 1A, A'). In prophase, when cyclin B activity reaches a high threshold, chromosome condensation occurs followed by Nuclear Envelope Breakdown (NEB) [1]. At this point vertebrate chromosomes appear as compact structures harboring an attachment point for the spindle microtubules physically recognizable as a primary constriction where the two sister chromatids are held together. The transition from an unshaped interphase chromosome to the highly structured mitotic chromosome (compare Figs. 1A and B) has fascinated researchers for several decades now; however a definite picture of how this process is achieved and regulated is not yet in our hands and it will require more investigation to comprehend the complete process. From a biochemical point of view a vertebrate mitotic chromosomes is composed of DNA, histone proteins (60%) and non-histone proteins (40%) [6]. I will discuss below what is known to date on the contribution of these two different classes

  18. Chromosomal imbalances in successive moments of human bladder urothelial carcinoma

    DEFF Research Database (Denmark)

    Nascimento e Pontes, Merielen Garcia; da Silveira, Sara Martorelli; Trindade Filho, José Carlos de Souza;

    2013-01-01

    in 16p12, in line with suggestions that these chromosome regions contain genes critical for urinary bladder carcinogenesis. Within a same patient, tumors and their respective recurrences showed common genomic losses and gains, which implies that the genomic profile acquired by primary tumors...... cells expressing the p53 protein, suggesting that the apparently normal urothelium was genomically unstable. No numerical alterations of the chromosomes 7, 17, and 9p21 region were found by FISH during the periods "free-of-neoplasia." Our data are informative for further studies to better understand...

  19. Rapid de novo evolution of X chromosome dosage compensation in Silene latifolia, a plant with young sex chromosomes.

    Science.gov (United States)

    Muyle, Aline; Zemp, Niklaus; Deschamps, Clothilde; Mousset, Sylvain; Widmer, Alex; Marais, Gabriel A B

    2012-01-01

    Silene latifolia is a dioecious plant with heteromorphic sex chromosomes that have originated only ∼10 million years ago and is a promising model organism to study sex chromosome evolution in plants. Previous work suggests that S. latifolia XY chromosomes have gradually stopped recombining and the Y chromosome is undergoing degeneration as in animal sex chromosomes. However, this work has been limited by the paucity of sex-linked genes available. Here, we used 35 Gb of RNA-seq data from multiple males (XY) and females (XX) of an S. latifolia inbred line to detect sex-linked SNPs and identified more than 1,700 sex-linked contigs (with X-linked and Y-linked alleles). Analyses using known sex-linked and autosomal genes, together with simulations indicate that these newly identified sex-linked contigs are reliable. Using read numbers, we then estimated expression levels of X-linked and Y-linked alleles in males and found an overall trend of reduced expression of Y-linked alleles, consistent with a widespread ongoing degeneration of the S. latifolia Y chromosome. By comparing expression intensities of X-linked alleles in males and females, we found that X-linked allele expression increases as Y-linked allele expression decreases in males, which makes expression of sex-linked contigs similar in both sexes. This phenomenon is known as dosage compensation and has so far only been observed in evolutionary old animal sex chromosome systems. Our results suggest that dosage compensation has evolved in plants and that it can quickly evolve de novo after the origin of sex chromosomes.

  20. Whole-genome and chromosome evolution associated with host adaptation and speciation of the wheat pathogen Mycosphaerella graminicola.

    Directory of Open Access Journals (Sweden)

    Eva H Stukenbrock

    2010-12-01

    Full Text Available The fungus Mycosphaerella graminicola has been a pathogen of wheat since host domestication 10,000-12,000 years ago in the Fertile Crescent. The wheat-infecting lineage emerged from closely related Mycosphaerella pathogens infecting wild grasses. We use a comparative genomics approach to assess how the process of host specialization affected the genome structure of M. graminicola since divergence from the closest known progenitor species named M. graminicola S1. The genome of S1 was obtained by Illumina sequencing resulting in a 35 Mb draft genome sequence of 32X. Assembled contigs were aligned to the previously sequenced M. graminicola genome. The alignment covered >90% of the non-repetitive portion of the M. graminicola genome with an average divergence of 7%. The sequenced M. graminicola strain is known to harbor thirteen essential chromosomes plus eight dispensable chromosomes. We found evidence that structural rearrangements significantly affected the dispensable chromosomes while the essential chromosomes were syntenic. At the nucleotide level, the essential and dispensable chromosomes have evolved differently. The average synonymous substitution rate in dispensable chromosomes is considerably lower than in essential chromosomes, whereas the average non-synonymous substitution rate is three times higher. Differences in molecular evolution can be related to different transmission and recombination patterns, as well as to differences in effective population sizes of essential and dispensable chromosomes. In order to identify genes potentially involved in host specialization or speciation, we calculated ratios of synonymous and non-synonymous substitution rates in the >9,500 aligned protein coding genes. The genes are generally under strong purifying selection. We identified 43 candidate genes showing evidence of positive selection, one encoding a potential pathogen effector protein. We conclude that divergence of these pathogens was

  1. Gametocidal chromosomes enhancing chromosome aberration in common wheat induced by 5-azacytidine.

    Science.gov (United States)

    Su, W-Y; Cong, W-W; Shu, Y-J; Wang, D; Xu, G-H; Guo, C-H

    2013-07-08

    The gametocidal (Gc) chromosome from Aegilops spp induces chromosome mutation, which is introduced into common wheat as a tool of chromosome manipulation for genetic improvement. The Gc chromosome functions similar to a restriction-modification system in bacteria, in which DNA methylation is an important regulator. We treated root tips of wheat carrying Gc chromosomes with the hypomethylation agent 5-azacytidine; chromosome breakage and micronuclei were observed in these root tips. The frequency of aberrations differed in wheat containing different Gc chromosomes, suggesting different functions inducing chromosome breakage. Gc chromosome 3C caused the greatest degree of chromosome aberration, while Gc chromosome 3C(SAT) and 2C caused only slight chromosome aberration. Gc chromosome 3C induced different degrees of chromosome aberration in wheat varieties Triticum aestivum var. Chinese Spring and Norin 26, demonstrating an inhibition function in common wheat.

  2. Vitreous substitutes: challenges and directions

    Institute of Scientific and Technical Information of China (English)

    Qian-Ying; Gao; Yue; Fu; Yan-Nian; Hui

    2015-01-01

    The natural vitreous body has a fine structure and complex functions. The imitation of the natural vitreous body by vitreous substitutes is a challenging work for both researchers and ophthalmologists. Gases, silicone oil, heavy silicone oil and hydrogels, particularly the former two vitreous substitutes are clinically widely used with certain complications. Those, however, are not real artificial vitreous due to lack of structure and function like the natural vitreous body. This article reviews the situations, challenges, and future directions in the development of vitreous substitutes, particularly the experimental and clinical use of a new artificial foldable capsular vitreous body.

  3. Genetic investigations on 8 patients affected by ring 20 chromosome syndrome

    Directory of Open Access Journals (Sweden)

    Giordano Lucio

    2010-10-01

    Full Text Available Abstract Background Mosaic Chromosome 20 ring [r(20] is a chromosomal disorder associated with a rare syndrome characterized by a typical seizure phenotype, a particular electroclinical pattern, cognitive impairment, behavioural problems and absence of a consistent pattern of dysmorphology. The pathogenic mechanism underlying seizures disorders in r(20 syndrome is still unknown. We performed a detailed clinical and genetic study on 8 patients with r(20 chromosome, aimed at detecting the genetic mechanism underlying r(20 syndrome. Methods We submitted 8 subjects with a previous diagnosis of ring 20 chromosome mosaicism to a clinical re-evaluation, followed by cytogenetic, FISH, array-CGH and molecular analyses. The genetic study was also extended to their available parents. Results FISH and array-CGH experiments indicate that cryptic deletions on chromosome 20 are not the cause of the r(20 chromosome associated disease. Moreover, no evidence of chromosome 20 uniparental disomy was found. Analysis of FISH signals given by variant in size alphoid tandem repeats probes on the normal chromosome 20 and the r(20 chromosome in the mosaic carriers suggests that the r(20 chromosome is the same chromosome not circularized in the "normal" cell line. Conclusions Higher percentages of r(20 chromosome cells were observed to be related with precocious age at seizure onset and with resistance to antiepileptic drug treatment. Behavioural problems also seem to be associated with higher percentages of r(20 chromosome cells. Our results suggest that an epigenetic mechanism perturbing the expression of genes close to the telomeric regions, rather than deletion of genes located at the distal 20p and/or 20q regions, may underlie the manifestation of r(20 syndrome.

  4. Chromosome segregation in Vibrio cholerae.

    Science.gov (United States)

    Ramachandran, Revathy; Jha, Jyoti; Chattoraj, Dhruba K

    2014-01-01

    The study of chromosome segregation is currently one of the most exciting research frontiers in cell biology. In this review, we discuss our current knowledge of the chromosome segregation process in Vibrio cholerae, based primarily on findings from fluorescence microscopy experiments. This bacterium is of special interest because of its eukaryotic feature of having a divided genome, a feature shared with 10% of known bacteria. We also discuss how the segregation mechanisms of V. cholerae compare with those in other bacteria, and highlight some of the remaining questions regarding the process of bacterial chromosome segregation.

  5. Numerous transitions of sex chromosomes in Diptera.

    Science.gov (United States)

    Vicoso, Beatriz; Bachtrog, Doris

    2015-04-01

    Many species groups, including mammals and many insects, determine sex using heteromorphic sex chromosomes. Diptera flies, which include the model Drosophila melanogaster, generally have XY sex chromosomes and a conserved karyotype consisting of six chromosomal arms (five large rods and a small dot), but superficially similar karyotypes may conceal the true extent of sex chromosome variation. Here, we use whole-genome analysis in 37 fly species belonging to 22 different families of Diptera and uncover tremendous hidden diversity in sex chromosome karyotypes among flies. We identify over a dozen different sex chromosome configurations, and the small dot chromosome is repeatedly used as the sex chromosome, which presumably reflects the ancestral karyotype of higher Diptera. However, we identify species with undifferentiated sex chromosomes, others in which a different chromosome replaced the dot as a sex chromosome or in which up to three chromosomal elements became incorporated into the sex chromosomes, and others yet with female heterogamety (ZW sex chromosomes). Transcriptome analysis shows that dosage compensation has evolved multiple times in flies, consistently through up-regulation of the single X in males. However, X chromosomes generally show a deficiency of genes with male-biased expression, possibly reflecting sex-specific selective pressures. These species thus provide a rich resource to study sex chromosome biology in a comparative manner and show that similar selective forces have shaped the unique evolution of sex chromosomes in diverse fly taxa.

  6. Polymorphic haplotypes on R408BW PKU and normal PAH chromosomes in Quebec and European populations

    Energy Technology Data Exchange (ETDEWEB)

    Byck, S.; Morgan, K.; Scriver, C.R. [McGill Univ., Montreal (Canada)] [and others

    1994-09-01

    The R408W mutation in the phenylalanine hydroxylase gene (PAH) is associated with haplotype 2.3 (RFLP haplotype 2, VNTR 3 of the HindIII system) in most European populations. Another chromosome, first observed in Quebec and then in northwest Europe, carries R408W on haplotype 1.8. The occurrence of the R408W mutation on two different PKU chromosomes could be the result of intragenic recombination, recurrent mutation or gene conversion. In this study, we analyzed both normal and R408W chromosomes carrying 1.8 and 2.3 haplotypes in Quebec and European populations; we used the TCTA{sub (n)} short tandem repeat sequence (STR) at the 5{prime} end of the PAH gene and the HindIII VNTR system at the 3{prime} end of the PAH gene to characterize chromosomes. Fourteen of sixteen R408W chromosomes from {open_quotes}Celtic{close_quotes} families in Quebec and the United Kingdom (UK) harbor a 244 bp STR allele; the remaining two chromosomes, carry a 240 bp or 248bp STR allele. Normal chromosomes (n=18) carry the 240 bp STR allele. R408W chromosomes are different from mutant H1.8 chromosomes; mutant H2.3 carries the 240 bp STR allele (14 of 16 chromosomes) or the 236 allele (2 of 16 chromosomes). The HindIII VNTR comprises variable numbers of 30 bp repeats (cassettes); the repeats also vary in nucleotide sequence. Variation clusters toward the 3{prime} end of cassettes and VNTRs. VNTR 3 alleles on normal H2 (n=9) and mutant R408W H2 (n=19) chromosomes were identical. VNTR 8 alleles on normal H1 chromosomes (n=9) and on R408W H1 chromosomes (n=15) differ by 1 bp substitution near the 3{prime} end of the 6th cassette. In summary, the mutant H1.8 chromosome harboring the R408W mutation has unique features at both the 5{prime} and 3{prime} end of the gene that distinguish it from the mutant H2.3 and normal H1.8 and H2.3 counterparts. The explanation for the occurrence of R408W on two different PAH haplotypes is recurrent mutation affecting the CpG dinucleotide in PAH codon 408.

  7. Factor substitution in nursing homes.

    Science.gov (United States)

    Cawley, John; Grabowski, David C; Hirth, Richard A

    2006-03-01

    This paper studies factor substitution in one important sector: the nursing home industry. Specifically, we measure the extent to which nursing homes substitute materials for labor when labor becomes relatively more expensive. From a policy perspective, factor substitution in this market is important because materials-intensive methods of care are associated with greater risks of morbidity and mortality among nursing home residents. Studying longitudinal data from 1991 to 2000 on nearly every nursing home in the United States, we use the method of instrumental variables (IV) to address measurement error in nursing home wages. The results from the IV models yield evidence of factor substitution: higher nursing home wages are associated with greater use of psychoactive drugs and lower quality.

  8. Nucleophilic Substitution by Benzodithioate Anions.

    Science.gov (United States)

    Bonnans-Plaisance, Chantal; Gressier, Jean-Claude

    1988-01-01

    Describes a two-session experiment designed to provide a good illustration of, and to improve student knowledge of, the Grignard reaction and nucleophilic substitution. Discusses the procedure, experimental considerations, and conclusion of this experiment. (CW)

  9. Post-zygotic breakage of a dicentric chromosome results in mosaicism for a telocentric 9p marker chromosome in a boy with developmental delay.

    Science.gov (United States)

    Pedurupillay, C R J; Misceo, D; Gamage, T H; Dissanayake, V H W; Frengen, E

    2014-01-01

    Chromosomal rearrangements resulting in an inverted duplication and a terminal deletion (inv dup del) can occur due to three known mechanisms, two of them resulting in a normal copy region between the duplicated regions. These mechanisms involve the formation of a dicentric chromosome, which undergo breakage during cell division resulting in cells with either an inverted duplication and deletion or a terminal deletion. We describe a mosaic 3 year old patient with two cell lines carrying a chromosome 9p deletion where one of the cell lines contains an additional telocentric marker chromosome. Our patient is mosaic for the product of a double breakage of a dicentric chromosome including a centric fission. Mosaicism involving different rearrangements of the same chromosome is rare and suggests an early mitotic breakage event. Chr9p terminal deletions associated with duplications have previously been reported in 11 patients. We compare the clinical features of all 12 patients including the patient that we report here. To the best to our knowledge this is a first case reported where the double breakage occurred in the dicentric derivative chromosome 9.

  10. Chromosome fragility in Freemartin cattle

    Directory of Open Access Journals (Sweden)

    V. Barbieri

    2010-04-01

    Full Text Available The aim of the present study was to verify chromosome fragility in freemartin cattle using chromosome aberration (CA and sister chromatid exchange (SCE tests. A total of eighteen co-twins were investigated. Fourteen animals were identified as cytogenetically chimeric (2n=60, XX/XY while 4 were classified as normal. Freemartin cattle showed a higher percentage of aneuploid cells (18.64% and highly significant statistical differences (P < 0.001 in mean values of gaps (4.53 ± 2.05, chromatid breaks (0.26 ± 0.51, and significant statistical differences (P < 0.005 in mean values of chromosome breaks (0.12 ± 0.43 when compared to 10 control animals from single births (aneuploid cells, 11.20%; gaps, 2.01 ± 1.42; chromatid breaks, 0.05 ± 0.22; chromosome breaks, 0.02 ± 0.14.

  11. DEAD-box RNA helicase Belle/DDX3 and the RNA interference pathway promote mitotic chromosome segregation.

    Science.gov (United States)

    Pek, Jun Wei; Kai, Toshie

    2011-07-19

    During mitosis, faithful inheritance of genetic material is achieved by chromosome segregation, as mediated by the condensin I and II complexes. Failed chromosome segregation can result in neoplasm formation, infertility, and birth defects. Recently, the germ-line-specific DEAD-box RNA helicase Vasa was demonstrated to promote mitotic chromosome segregation in Drosophila by facilitating robust chromosomal localization of Barren (Barr), a condensin I component. This mitotic function of Vasa is mediated by Aubergine and Spindle-E, which are two germ-line components of the Piwi-interacting RNA pathway. Faithful segregation of chromosomes should be executed both in germ-line and somatic cells. However, whether a similar mechanism also functions in promoting chromosome segregation in somatic cells has not been elucidated. Here, we present evidence that belle (vasa paralog) and the RNA interference pathway regulate chromosome segregation in Drosophila somatic cells. During mitosis, belle promotes robust Barr chromosomal localization and chromosome segregation. Belle's localization to condensing chromosomes depends on dicer-2 and argonaute2. Coimmunoprecipitation experiments indicated that Belle interacts with Barr and Argonaute2 and is enriched at endogenous siRNA (endo-siRNA)-generating loci. Our results suggest that Belle functions in promoting chromosome segregation in Drosophila somatic cells via the endo-siRNA pathway. DDX3 (human homolog of belle) and DICER function in promoting chromosome segregation and hCAP-H (human homolog of Barr) localization in HeLa cells, indicating a conserved function for those proteins in human cells. Our results suggest that the RNA helicase Belle/DDX3 and the RNA interference pathway perform a common role in regulating chromosome segregation in Drosophila and human somatic cells.

  12. Chromosome Segregation in Vibrio cholerae

    OpenAIRE

    Ramachandran, R.; Jha, J.; Chattoraj, DK

    2014-01-01

    The study of chromosome segregation is currently one of the most exciting research frontiers in cell biology. In this review, we discuss our current knowledge of the chromosome segregation process in Vibrio cholerae, based primarily on findings from fluorescence microscopy experiments. This bacterium is of special interest because of its eukaryotic feature of having a divided genome, a feature shared with 10% of known bacteria. We also discuss how the segregation mechanisms of V. cholerae com...

  13. Cytomolecular discrimination of the A(m) chromosomes of Triticum monococcum and the A chromosomes of Triticum aestivum using microsatellite DNA repeats.

    Science.gov (United States)

    Megyeri, Mária; Mikó, Péter; Farkas, András; Molnár-Láng, Márta; Molnár, István

    2017-02-01

    The cytomolecular discrimination of the A(m)- and A-genome chromosomes facilitates the selection of wheat-Triticum monococcum introgression lines. Fluorescence in situ hybridisation (FISH) with the commonly used DNA probes Afa family, 18S rDNA and pSc119.2 showed that the more complex hybridisation pattern obtained in T. monococcum relative to bread wheat made it possible to differentiate the A(m) and A chromosomes within homoeologous groups 1, 4 and 5. In order to provide additional chromosomal landmarks to discriminate the A(m) and A chromosomes, the microsatellite repeats (GAA)n, (CAG)n, (CAC)n, (AAC)n, (AGG)n and (ACT)n were tested as FISH probes. These showed that T. monococcum chromosomes have fewer, generally weaker, simple sequence repeat (SSR) signals than the A-genome chromosomes of hexaploid wheat. A differential hybridisation pattern was observed on 6A(m) and 6A chromosomes with all the SSR probes tested except for the (ACT)n probe. The 2A(m) and 2A chromosomes were differentiated by the signals given by the (GAA)n, (CAG)n and (AAC)n repeats, while only (GAA)n discriminated the chromosomes 3A(m) and 3A. Chromosomes 7A(m) and 7A could be differentiated by the lack of (GAA)n and (AGG)n signals on 7A. As potential landmarks for identifying the A(m) chromosomes, SSR repeats will facilitate the introgression of T. monococcum chromatin into wheat.

  14. B chromosomes and sex in animals.

    Science.gov (United States)

    Camacho, J P M; Schmid, M; Cabrero, J

    2011-01-01

    Supernumerary (B) chromosomes are dispensable elements found in many eukaryote genomes in addition to standard (A) chromosomes. In many respects, B chromosomes resemble sex chromosomes, so that a common ancestry for them has frequently been suggested. For instance, B chromosomes in grasshoppers, and other insects, show a pycnotic cycle of condensation-decondensation during meiosis remarkably similar to that of the X chromosome. In some cases, B chromosome size is even very similar to that of the X chromosome. These resemblances have led to suggest the X as the B ancestor in many cases. In addition, sex chromosome origin from B chromosomes has also been suggested. In this article, we review the existing evidence for both evolutionary pathways, as well as sex differences for B frequency at adult and embryo progeny levels, B chromosome effects or B chromosome transmission. In addition, we review cases found in the literature showing sex-ratio distortion associated with B chromosome presence, the most extreme case being the paternal sex ratio (PSR) chromosomes in some Hymenoptera. We finally analyse the possibility of B chromosome regularisation within the host genome and, as a consequence of it, whether B chromosomes can become regular members of the host genome.

  15. Origin and domestication of papaya Yh chromosome

    Science.gov (United States)

    Sex in papaya is controlled by a pair of nascent sex chromosomes. Females are XX, and two slightly different Y chromosomes distinguish males (XY) and hermaphrodites (XYh). The hermaphrodite-specific region of the Yh chromosome (HSY) and its X chromosome counterpart were sequenced and analyzed previo...

  16. Possible interspecific origin of the B chromosome of Hypsiboas albopunctatus (Spix, 1824 (Anura, Hylidae, revealed by microdissection, chromosome painting, and reverse hybridisation

    Directory of Open Access Journals (Sweden)

    Simone Gruber

    2014-08-01

    Full Text Available The B chromosome in the hylid Hypsiboas albopunctatus (2n = 22 + B is small, almost entirely composed of C-positive heterochromatin, and does not pair with any chromosome of the A complement. B probe, obtained by microdissection and DOP-PCR amplification, was used to search for homology between the B and regular chromosomes of H. albopunctatus and of the related species H. raniceps (Cope, 1862. Reverse hybridisation was also carried out in the investigation. The B probe exclusively painted the supernumerary, not hybridising any other chromosomes in H. albopunctatus, but all H. raniceps chromosomes showed small labelling signals. This result might be an indication that differences exist between the repetitive sequences of A and B chromosomes of H. albopunctatus, and that the chromosomes of H. raniceps and the heterochromatin of the B chromosome of H. albopunctatus are enriched with the same type of repetitive DNA. In meiotic preparations, the B labelled about 30% of scored spermatids, revealing a non-mendelian inheritance, and the painted B in micronucleus suggests that the supernumerary is eliminated from germ line cells. Although our results could suggest an interespecific origin of the B at first sight, further analysis on its repetitive sequences is still necessary. Nevertheless, the accumulation of repetitive sequences, detected in another species, even though closely related, remains an intriguing question.

  17. Numerically abnormal chromosome constitutions in humans

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1993-12-31

    Chapter 24, discusses numerically abnormal chromosome constitutions in humans. This involves abnormalities of human chromosome number, including polyploidy (when the number of sets of chromosomes increases) and aneuploidy (when the number of individual normal chromosomes changes). Chapter sections discuss the following chromosomal abnormalities: human triploids, imprinting and uniparental disomy, human tetraploids, hydatidiform moles, anomalies caused by chromosomal imbalance, 13 trisomy (D{sub 1} trisomy, Patau syndrome), 21 trisomy (Down syndrome), 18 trisomy syndrome (Edwards syndrome), other autosomal aneuploidy syndromes, and spontaneous abortions. The chapter concludes with remarks on the nonrandom participation of chromosomes in trisomy. 69 refs., 3 figs., 4 tabs.

  18. Microdissection of additional chromosome in common wheat-Th.intermedium TAI-27 and screening of its special probe

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    It was identified that there were 4 St chromosomes derived from Th.intermedium in common wheat-Th.intermedium alien additional line TAI-27 by in situ hybridization.Two St chromosomes added to wheat chromosome in TAI-27 as well as two of them replaced two of 42 in wheat chromosomes.This indicates that TAI-27 is not only an alien additional line,but also a replacing line.The additional chromosomes in TAI-27 were microdissected and a microcloning library was constructed.A special probe of Th.intermedium was obtained from a microcloning library.The sequence analysis indicated that there were no homology with Genebank data.This makes it possible to screen genes with the disease-resistance,adversity-tolerance and fine character from Th.intermedium.

  19. Microdissection of additional chromosome in common wheat-Th. intermedium TAI-27 and screening of its special probe

    Institute of Scientific and Technical Information of China (English)

    田靫; 卢一凡; 邓继先; 李滨; 张学勇; 刘广田

    2000-01-01

    It was identified that there were 4 St chromosomes derived from Th, intermedium in common wheat-Th. intermedium alien additional line TAI-27 by in situ hybridization. Two St chromosomes added to wheat chromosome in TAI-27 as well as two of them replaced two of 42 in wheat chromosomes. This indicates that TAI-27 is not only an alien additional line, but also a replacing line. The additional chromosomes in TAI-27 were microdissected and a microcloning library was constructed. A special probe of Th. intermedium was obtained from a microcloning library. The sequence analysis indicated that there were no homology with Genebank data. This makes it possible to screen genes with the disease-resistance, adversity-tolerance and fine character from Th.intermedium.

  20. Flow karyotyping and sorting of human chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Gray, J.W.; Lucas, J.; Peters, D.; Pinkel, D.; Trask, B.; van den Engh, G.; Van Dilla, M.A.

    1986-07-16

    Flow cytometry and sorting are becoming increasingly useful as tools for chromosome classfication and for the detection of numerical and structural chromosome aberrations. Chromosomes of a single type can be purified with these tools to facilitate gene mapping or production of chromosome specific recombinant DNA libraries. For analysis of chromosomes with flow cytometry, the chromosomes are extracted from mitotic cells, stained with one or more fluorescent dyes and classified one-by-one according to their dye content(s). Thus, the flow approach is fundamentally different than conventional karyotyping where chromosomes are classified within the context of a metaphase spread. Flow sorting allows purification of chromosomes that can be distinguished flow cytometrically. The authors describe the basic principles of flow cytometric chromosome classification i.e. flow karyotyping, and chromosome sorting and describe several applications. 30 refs., 8 figs.

  1. pain2: A neuropathic pain QTL identified on rat chromosome 2.

    Science.gov (United States)

    Nissenbaum, Jonathan; Shpigler, Hagai; Pisanté, Anne; DelCanho, Sonia; Minert, Anne; Seltzer, Ze'ev; Devor, Marshall; Darvasi, Ariel

    2008-03-01

    We aimed to locate a chronic pain-associated QTL in the rat (Rattus norvegicus) based on previous findings of a QTL (pain1) on chromosome 15 of the mouse (Mus musculus). The work was based on rat selection lines HA (high autotomy) and LA (low autotomy) which show a contrasting pain phenotype in response to nerve injury in the neuroma model of neuropathic pain. An F(2) segregating population was generated from HA and LA animals. Phenotyped F(2) rats were genotyped on chromosome 7 and chromosome 2, regions that share a partial homology with mouse chromosome 15. Our interval mapping analysis revealed a LOD score value of 3.63 (corresponding to p=0.005 after correcting for multiple testing using permutations) on rat chromosome 2, which is suggestive of the presence of a QTL affecting the predisposition to neuropathic pain. This QTL was mapped to the 14-26cM interval of chromosome 2. Interestingly, this region is syntenic to mouse chromosome 13, rather than to the region of mouse chromosome 15 that contains pain1. This chromosomal position indicates that it is possibly a new QTL, and hence we name it pain2. Further work is needed to replicate and to uncover the underlying gene(s) in both species.

  2. Development and Identification of Introgression Lines from Cross of Oryza sativa and Oryza minuta

    Institute of Scientific and Technical Information of China (English)

    GUO Si-bin; WEI Yu; LI Xiao-qiong; LIU Kai-qiang; HUANG Feng-kuan; CHEN Cai-hong; GAO Guo-qing

    2013-01-01

    Introgression line population is effectively used in mapping quantitative trait loci (QTLs),identifying favorable genes,discovering hidden genetic variation,evaluating the action or interaction of QTLs in multiple conditions and providing the favorable experimental materials for plant breeding and genetic research.In this study,an advanced backcross and consecutive selfing strategy was used to develop introgression lines (ILs),which derived from an accession of Oryza minuta (accession No.101133) with BBCC genome,as the donor,and an elite indica cultivar IR24 (O.sativa),as the recipient.Introgression segments from O.minuta were screened using 164 polymorphic simple sequence repeat (SSR) markers in the genome of each IL.Introgressed segments carried by 131 ILs covered the whole O.sativa genome.The average number of homozygous O.minuta segments per introgression line was about 9.99.The average length of introgressed segments was approximate 14.78 cM,and about 79.64%of these segments had sizes less than 20 cM.In the genome of each introgression line,the O.minuta chromosomal segments harbored chromosomal fragments of O.sativa ranging from 1.15% to 27.6%,with an overall average of 8.57%.At each locus,the ratio of substitution of O.minuta alleles had a range of 1.5%-25.2%,with an average of 8.3% Based on the evaluation of the phenotype of these ILs,a wide range of alterations in morphological and yield-related traits were found.After inoculation,ILs 41,11 and 7 showed high resistance to bacterial blight,brown planthopper and whitebacked planthopper,respectively.These O.minuta-O.sativa ILs will serve as genetic materials for identifying and using favorable genes from O.minuta.

  3. Combined array-comparative genomic hybridization and single-nucleotide polymorphism-loss of heterozygosity analysis reveals complex changes and multiple forms of chromosomal instability in colorectal cancers

    DEFF Research Database (Denmark)

    Gaasenbeek, Michelle; Howarth, Kimberley; Rowan, Andrew J;

    2006-01-01

    infrequently showed gains/deletions or whole-chromosome LOH, but their near-diploid karyotypes concealed mitotic recombination frequencies similar to those of MSI- lines. We analyzed p53 and chromosome 18q (SMAD4) in detail, including mutation screening. Almost all MSI- lines showed LOH and/or deletion of p53...

  4. Chromosome isolation by flow sorting in Aegilops umbellulata and Ae. comosa and their allotetraploid hybrids Ae. biuncialis and Ae. geniculata.

    Directory of Open Access Journals (Sweden)

    István Molnár

    Full Text Available This study evaluates the potential of flow cytometry for chromosome sorting in two wild diploid wheats Aegilops umbellulata and Ae. comosa and their natural allotetraploid hybrids Ae. biuncialis and Ae. geniculata. Flow karyotypes obtained after the analysis of DAPI-stained chromosomes were characterized and content of chromosome peaks was determined. Peaks of chromosome 1U could be discriminated in flow karyotypes of Ae. umbellulata and Ae. biuncialis and the chromosome could be sorted with purities exceeding 95%. The remaining chromosomes formed composite peaks and could be sorted in groups of two to four. Twenty four wheat SSR markers were tested for their position on chromosomes of Ae. umbellulata and Ae. comosa using PCR on DNA amplified from flow-sorted chromosomes and genomic DNA of wheat-Ae. geniculata addition lines, respectively. Six SSR markers were located on particular Aegilops chromosomes using sorted chromosomes, thus confirming the usefulness of this approach for physical mapping. The SSR markers are suitable for marker assisted selection of wheat-Aegilops introgression lines. The results obtained in this work provide new opportunities for dissecting genomes of wild relatives of wheat with the aim to assist in alien gene transfer and discovery of novel genes for wheat improvement.

  5. Analysis of chromosome aberration data by hybrid-scale models

    Energy Technology Data Exchange (ETDEWEB)

    Indrawati, Iwiq [Research and Development on Radiation and Nuclear Biomedical Center, National Nuclear Energy Agency (Indonesia); Kumazawa, Shigeru [Nuclear Technology and Education Center, Japan Atomic Energy Research Institute, Honkomagome, Tokyo (Japan)

    2000-02-01

    This paper presents a new methodology for analyzing data of chromosome aberrations, which is useful to understand the characteristics of dose-response relationships and to construct the calibration curves for the biological dosimetry. The hybrid scale of linear and logarithmic scales brings a particular plotting paper, where the normal section paper, two types of semi-log papers and the log-log paper are continuously connected. The hybrid-hybrid plotting paper may contain nine kinds of linear relationships, and these are conveniently called hybrid scale models. One can systematically select the best-fit model among the nine models by among the conditions for a straight line of data points. A biological interpretation is possible with some hybrid-scale models. In this report, the hybrid scale models were applied to separately reported data on chromosome aberrations in human lymphocytes as well as on chromosome breaks in Tradescantia. The results proved that the proposed models fit the data better than the linear-quadratic model, despite the demerit of the increased number of model parameters. We showed that the hybrid-hybrid model (both variables of dose and response using the hybrid scale) provides the best-fit straight lines to be used as the reliable and readable calibration curves of chromosome aberrations. (author)

  6. Replication of Vibrio cholerae chromosome I in Escherichia coli: dependence on dam methylation

    DEFF Research Database (Denmark)

    Koch, Birgit; Ma, Xiaofang; Løbner-Olesen, Anders

    2010-01-01

    We successfully substituted Escherichia coli's origin of replication oriC with the origin region of Vibrio cholerae chromosome I (oriCIVc). Replication from oriCIVc initiated at a similar or slightly reduced cell mass compared to that of normal E. coli oriC. With respect to sequestration....... cholerae chromosome I replication, which similar to what is observed for E. coli. No hda homologue has been identified in V. cholerae yet. In V. cholerae, dam is essential for viability, whereas in E. coli, dam mutants are viable. Replacement of E. coli oriC with oriCIVc allowed us to specifically address...

  7. Methods of Reprogramming to Induced Pluripotent Stem Cell Associated with Chromosomal Integrity and Delineation of a Chromosome 5q Candidate Region for Growth Advantage.

    Science.gov (United States)

    Sobol, Maria; Raykova, Doroteya; Cavelier, Lucia; Khalfallah, Ayda; Schuster, Jens; Dahl, Niklas

    2015-09-01

    Induced pluripotent stem cells (iPSCs) have brought great promises for disease modeling and cell-based therapies. One concern related to the use of reprogrammed somatic cells is the loss of genomic integrity and chromosome stability, a hallmark for cancer and many other human disorders. We investigated 16 human iPSC lines reprogrammed by nonintegrative Sendai virus (SeV) and another 16 iPSC lines generated by integrative lentivirus for genetic changes. At early passages we detected cytogenetic rearrangements in 44% (7/16) of iPSC lines generated by lentiviral integration whereas the corresponding figure was 6% (1/16) using SeV-based delivery. The rearrangements were numerical and/or structural with chromosomes 5 and 12 as the most frequently involved chromosomes. Three iPSC lines with chromosome 5 aberrations were derived from one and the same donor. We present in this study the aberrant karyotypes including a duplication of chromosome 5q13q33 that restricts a candidate region for growth advantage. Our results suggest that the use of integrative lentivirus confers a higher risk for cytogenetic abnormalities at early passages when compared to SeV-based reprogramming. In combination, our findings expand the knowledge on acquired cytogenetic aberrations in iPSC after reprogramming and during culture.

  8. Inherited unbalanced structural chromosome abnormalities at prenatal chromosome analysis are rarely ascertained through recurrent miscarriage

    NARCIS (Netherlands)

    Franssen, M. T. M.; Korevaar, J. C.; Tjoa, W. M.; Leschot, N. J.; Bossuyt, P. M. M.; Knegt, A. C.; Suykerbuyk, R. F.; Hochstenbach, R.; van der Veen, F.; Goddijn, M.

    2008-01-01

    Objective To determine the mode of ascertainment of inherited unbalanced structural chromosome abnormalities detected at prenatal chromosome analysis. Methods From the databases of three centres for clinical genetics in the Netherlands, all cases of inherited unbalanced structural chromosome abnorma

  9. Confirmation of prenatal diagnosis of sex chromosome mosaicism.

    Science.gov (United States)

    McFadden, D E; Kalousek, D K

    1989-04-01

    Prenatal diagnosis of mosaicism causes problems in interpretation and in genetic counselling. Part of the difficulty with any prenatal diagnosis of mosaicism is interpretation of results without knowing the exact origin, embryonic or extraembryonic, of the abnormal cell line. To confuse the issue in cases of prenatal diagnosis of 45,X/46,XY mosaicism is the recent demonstration that a diagnosis of 45,X/46,XY made prenatally is not necessarily associated with the same phenotype as when diagnosed postnatally. We present two cases of prenatal diagnosis of sex chromosome mosaicism (45,X/46,XY and 45,X/47,XYY). Posttermination examination of the phenotypically normal male fetuses and their placentas established that the placenta was the most likely source of the 45,X cell line. An approach to confirming the prenatal diagnosis of sex chromosome mosaicism and establishing its origin utilizing detailed cytogenetic examination of both fetus and placenta is suggested.

  10. Dean flow fractionation of chromosomes

    Science.gov (United States)

    Hockin, Matt; Sant, Himanshu J.; Capecchi, Mario; Gale, Bruce K.

    2016-03-01

    Efforts to transfer intact mammalian chromosomes between cells have been attempted for more than 50 years with the consistent result being transfer of sub unit length pieces regardless of method. Inertial microfluidics is a new field that has shown much promise in addressing the fractionation of particles in the 2-20 μm size range (with unknown limits) and separations are based upon particles being carried by curving confined flows (within a spiral shaped, often rectangular flow chamber) and migrating to stable "equilibrium" positions of varying distance from a chamber wall depending on the balance of dean and lift forces. We fabricated spiral channels for inertial microfluidic separations using a standard soft lithography process. The concentration of chromosomes, small contaminant DNA and large cell debris in each outlets were evaluated using microscope (60X) and a flow cytometer. Using Dean Flow Fractionation, we were able to focus 4.5 times more chromosomes in outlet 2 compared to outlet 4 where most of the large debris is found. We recover 16% of the chromosomes in outlet #1- 50% in 2, 23% in 3 and 11% in 4. It should be noted that these estimates of recovery do not capture one piece of information- it actually may be that the chromosomes at each outlet are physically different and work needs to be done to verify this potential.

  11. Chromosome segregation in plant meiosis

    Directory of Open Access Journals (Sweden)

    Linda eZamariola

    2014-06-01

    Full Text Available Faithful chromosome segregation in meiosis is essential for ploidy stability over sexual life cycles. In plants, defective chromosome segregation caused by gene mutations or other factors leads to the formation of unbalanced or unreduced gametes creating aneuploid or polyploid progeny, respectively. Accurate segregation requires the coordinated execution of conserved processes occurring throughout the two meiotic cell divisions. Synapsis and recombination ensure the establishment of chiasmata that hold homologous chromosomes together allowing their correct segregation in the first meiotic division, which is also tightly regulated by cell-cycle dependent release of cohesin and monopolar attachment of sister kinetochores to microtubules. In meiosis II, bi-orientation of sister kinetochores and proper spindle orientation correctly segregate chromosomes in four haploid cells. Checkpoint mechanisms acting at kinetochores control the accuracy of kinetochore-microtubule attachment, thus ensuring the completion of segregation. Here we review the current knowledge on the processes taking place during chromosome segregation in plant meiosis, focusing on the characterization of the molecular factors involved.

  12. The Reduction of Chromosome Number in Meiosis Is Determined by Properties Built into the Chromosomes

    OpenAIRE

    Paliulis, Leocadia V.; Nicklas, R. Bruce

    2000-01-01

    In meiosis I, two chromatids move to each spindle pole. Then, in meiosis II, the two are distributed, one to each future gamete. This requires that meiosis I chromosomes attach to the spindle differently than meiosis II chromosomes and that they regulate chromosome cohesion differently. We investigated whether the information that dictates the division type of the chromosome comes from the whole cell, the spindle, or the chromosome itself. Also, we determined when chromosomes can switch from ...

  13. Magnesium substitution in brushite cements.

    Science.gov (United States)

    Alkhraisat, Mohammad Hamdan; Cabrejos-Azama, Jatsue; Rodríguez, Carmen Rueda; Jerez, Luis Blanco; Cabarcos, Enrique López

    2013-01-01

    The use of magnesium-doped ceramics has been described to modify brushite cements and improve their biological behavior. However, few studies have analyzed the efficiency of this approach to induce magnesium substitution in brushite crystals. Mg-doped ceramics composed of Mg-substituted β-TCP, stanfieldite and/or farringtonite were reacted with primary monocalcium phosphate (MCP) in the presence of water. The cement setting reaction has resulted in the formation of brushite and newberyite within the cement matrix. Interestingly, the combination of SAED and EDX analyses of single crystal has indicated the occurrence of magnesium substitution within brushite crystals. Moreover, the effect of magnesium ions on the structure, and mechanical and setting properties of the new cements was characterized as well as the release of Ca(2+) and Mg(2+) ions. Further research would enhance the efficiency of the system to incorporate larger amounts of magnesium ions within brushite crystals.

  14. On Regular Power-Substitution

    Institute of Scientific and Technical Information of China (English)

    Huanyin CHEN

    2009-01-01

    The necessary and sufficient conditions under which a ring satisfies regular power-substitution are investigated. It is shown that a ring R satisfies regular power-substitution if and only if a(-~)b in R implies that there exist n ∈ N and a U ∈ GLn(R) such that aU =Ub if and only if for any regular x ∈ R there exist m,n ∈ N and U ∈ GLn(R) such that xmIn = xmUxm, where a(-~)b means that there exists x, y, z ∈ R such that a = ybx, b = xaz and x = xyx = xzx. It is proved that every directly finite simple ring satisfies regular power-substitution. Some applications for stably free R-modules are also obtained.

  15. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted...

  16. Paternal uniparental isodisomy for human chromosome 20 and absence of external ears

    Energy Technology Data Exchange (ETDEWEB)

    Spinner, N.B.; Rand, E.; McDonald-McGinn, D.M. [Childrens Hospital of Philadelphia, PA (United States)] [and others

    1994-09-01

    Uniparental disomy can cause disease if the involved chromosomal region contains imprinted genes. Uniparental disomy for portions of human chromosomes 6, 7, 9, 11, 14 and 15 have been associated with abnormal phenotypes. We studied a patient with multiple abnormalities including an absent left ear with a small right ear remnant, microcephaly, congenital heart disease and Hirschprung`s disease. Cytogenetics revealed a 45,XY,-20,-20,+ter rea(20;20)(p13;p13) in 10/10 cells from bone marrow and 20/20 cells from peripheral blood. Analysis of a skin culture revealed a second cell line with trisomy 20 resulting from an apparently normal chromosome 20 in addition to the terminally rearranged chromosome, in 8/100 cells studied. The unusual phenotype of our patient was not consistent with previously reported cases of deletions of 20p or mosaic trisomy 20. We hypothesized that the patient`s phenotype could either result from deletion of both copies of a gene near the p arm terminus of chromosome 20 or from uniparental disomy of chromosome 20. There were no alterations or rearrangements of PTP-alpha (which maps to distal 20p) by Southern or Northern blot analysis. A chromosome 20 sub-telomeric probe was found to be present on the rearranged 20 by FISH suggesting that subtelomeric sequences have not been lost as a consequece of this rearrangement. To determine the parental origin of the 2 chromosome 20`s in the terminal rearrangement, we studied the genotypes of the proband and his parents in lymphoblastoid cell lines at 8 polymorphic loci. Genotypes at D20S115, D20S186, and D20S119 indicated that there was paternal isodisomy. Other loci were uninformative. This is the first example of uniparental disomy for chromosome 20. Further studies are warranted to correlate phenotype with uniparental inheritance of this chromosome.

  17. Development and characterization of Brassica juncea – fruticulosa introgression lines exhibiting resistance to mustard aphid (Lipaphis erysimi Kalt

    Directory of Open Access Journals (Sweden)

    Atri Chhaya

    2012-11-01

    Full Text Available Abstract Background Mustard aphid is a major pest of Brassica oilseeds. No source for aphid resistance is presently available in Brassica juncea . A wild crucifer, Brassica fruticulosa is known to be resistant to mustard aphid. An artificially synthesized amphiploid, AD-4 (B. fruticulosa × B. rapa var. brown sarson was developed for use as a bridge species to transfer fruticulosa resistance to B. juncea. Using the selfed backcross we could select a large number of lines with resistance to mustard aphid. This paper reports cytogenetic stability of introgression lines, molecular evidence for alien introgression and their reaction to mustard aphid infestation. Results Majority of introgression lines had expected euploid chromosome number(2n= 36, showed normal meiosis and high pollen grain fertility. Well-distributed and transferable simple-sequence repeats (SSR markers for all the 18 B. juncea chromosomes helped to characterize introgression events. Average proportions of recipient and donor genome in the substitution lines were 49.72 and 35.06%, respectively. Minimum alien parent genome presence (27.29% was observed in the introgression line, Ad3K-280 . Introgressed genotypes also varied for their resistance responses to mustard aphid infestations under artificial release conditions for two continuous seasons. Some of the test genotypes showed consistent resistant reaction. Conclusions B.juncea-fruticulosa introgression set may prove to be a very powerful breeding tool for aphid resistance related QTL/gene discovery and fine mapping of the desired genes/QTLs to facilitate marker assisted transfer of identified gene(s for mustard aphid resistance in the background of commercial mustard genotypes.

  18. Substituted decision making: elder guardianship.

    Science.gov (United States)

    Leatherman, Martha E; Goethe, Katherine E

    2009-11-01

    The goal of this column is to help experienced clinicians navigate the judicial system when they are confronted with requests for capacity evaluations that involve guardianship (conservatorship). The interface between the growing elderly medical population and increasing requests for substituted decision making is becoming more complex. This column will help practicing psychiatrists understand the medical, legal, and societal factors involved in adult guardianship. Such understanding is necessary in order to effectively perform guardianship evaluations and adequately inform courts, patients, and families about the psychiatric diagnoses central to substituted decision making.

  19. Hypoxic radiosensitizers: substituted styryl derivatives.

    Science.gov (United States)

    Nudelman, A; Falb, E; Odesa, Y; Shmueli-Broide, N

    1994-10-01

    A number of novel styryl epoxides, N-substituted-styryl-ethanolamines, N-mono and N,N'-bis-(2-hydroxyethyl)-cinnamamides--analogues to the known radiosensitizers RSU-1069, pimonidazole and etanidazole--display selective hypoxic radiosensitizing activity. The styryl group, especially when substituted by electron withdrawing groups, was found to be bioisosteric to the nitroimidazolyl functionality. The most active derivative 2-(2'-nitrophenyl)ethen-1-yl-oxirane 8a displayed a sensitizer enhancement ratio (SER) of 5 relative to misonidazole.

  20. Giemsa C-banding of Barley Chromosomes. I: Banding Pattern Polymorphism

    DEFF Research Database (Denmark)

    Linde-Laursen, Ib

    1978-01-01

    Twenty barley (Hordeum vulgare) lines studied had a common basic chromosome banding pattern. Most bands ranged from medium to very small in size. The most conspicuous banding occurred at or near the centromeres, in the proximal, intercalary parts of most chromosome arms and beside the secondary c...... 7. Seventeen differently banded karyotypes were found. Some banding pattern polymorphisms can be used in cytological and cytogenetic studies....

  1. Artificially introduced aneuploid chromosomes assume a conserved position in colon cancer cells.

    Directory of Open Access Journals (Sweden)

    Kundan Sengupta

    Full Text Available BACKGROUND: Chromosomal aneuploidy is a defining feature of carcinomas. For instance, in colon cancer, an additional copy of Chromosome 7 is not only observed in early pre-malignant polyps, but is faithfully maintained throughout progression to metastasis. These copy number changes show a positive correlation with average transcript levels of resident genes. An independent line of research has also established that specific chromosomes occupy a well conserved 3D position within the interphase nucleus. METHODOLOGY/PRINCIPAL FINDINGS: We investigated whether cancer-specific aneuploid chromosomes assume a 3D-position similar to that of its endogenous homologues, which would suggest a possible correlation with transcriptional activity. Using 3D-FISH and confocal laser scanning microscopy, we show that Chromosomes 7, 18, or 19 introduced via microcell-mediated chromosome transfer into the parental diploid colon cancer cell line DLD-1 maintain their conserved position in the interphase nucleus. CONCLUSIONS: Our data is therefore consistent with the model that each chromosome has an associated zip code (possibly gene density that determines its nuclear localization. Whether the nuclear localization determines or is determined by the transcriptional activity of resident genes has yet to be ascertained.

  2. Site-specific genetic engineering of the Anopheles gambiae Y chromosome.

    Science.gov (United States)

    Bernardini, Federica; Galizi, Roberto; Menichelli, Miriam; Papathanos, Philippos-Aris; Dritsou, Vicky; Marois, Eric; Crisanti, Andrea; Windbichler, Nikolai

    2014-05-27

    Despite its function in sex determination and its role in driving genome evolution, the Y chromosome remains poorly understood in most species. Y chromosomes are gene-poor, repeat-rich and largely heterochromatic and therefore represent a difficult target for genetic engineering. The Y chromosome of the human malaria vector Anopheles gambiae appears to be involved in sex determination although very little is known about both its structure and function. Here, we characterize a transgenic strain of this mosquito species, obtained by transposon-mediated integration of a transgene construct onto the Y chromosome. Using meganuclease-induced homologous repair we introduce a site-specific recombination signal onto the Y chromosome and show that the resulting docking line can be used for secondary integration. To demonstrate its utility, we study the activity of a germ-line-specific promoter when located on the Y chromosome. We also show that Y-linked fluorescent transgenes allow automated sex separation of this important vector species, providing the means to generate large single-sex populations. Our findings will aid studies of sex chromosome function and enable the development of male-exclusive genetic traits for vector control.

  3. Neocentric X-chromosome in a girl with Turner-like syndrome

    Directory of Open Access Journals (Sweden)

    Hemmat Morteza

    2012-06-01

    Full Text Available Abstract Background Neocentromeres are rare human chromosomal aberrations in which a new centromere has formed in a previously non-centromeric location. We report the finding of a structurally abnormal X chromosome with a neocentromere in a 15-year-old girl with clinical features suggestive of Turner syndrome, including short stature and primary amenorrhea. Result G-banded chromosome analysis revealed a mosaic female karyotype involving two abnormal cell lines. One cell line (84% of analyzed metaphases had a structurally abnormal X chromosome (duplication of the long arm and deletion of the short arm and a normal X chromosome. The other cell line (16% of cells exhibited monosomy X. C-banding studies were negative for the abnormal X chromosome. FISH analysis revealed lack of hybridization of the abnormal X chromosome with both the X centromere-specific probe and the “all human centromeres” probe, a pattern consistent with lack of the X chromosome endogenous centromere. A FISH study using an XIST gene probe revealed the presence of two XIST genes, one on each long arm of the iso(Xq, required for inactivation of the abnormal X chromosome. R-banding also demonstrated inactivation of the abnormal X chromosome. An assay for centromeric protein C (CENP-C was positive on both the normal and the abnormal X chromosomes. The position of CENP-C in the abnormal X chromosome defined a neocentromere, which explains its mitotic stability. The karyotype is thus designated as 46,X,neo(X(qter- > q12::q12- > q21.2- > neo- > q21.2- > qter[42]/45,X[8], which is consistent with stigmata of Turner syndrome. The mother of this patient has a normal karyotype; however, the father was not available for study. Conclusion To our knowledge, this is the first case of mosaic Turner syndrome involving an analphoid iso(Xq chromosome with a proven neocentromere among 90 previously described cases with a proven neocentromere.

  4. Engineering targeted chromosomal amplifications in human breast epithelial cells.

    Science.gov (United States)

    Springer, Simeon; Yi, Kyung H; Park, Jeenah; Rajpurohit, Anandita; Price, Amanda J; Lauring, Josh

    2015-07-01

    Chromosomal amplifications are among the most common genetic alterations found in human cancers. However, experimental systems to study the processes that lead to specific, recurrent amplification events in human cancers are lacking. Moreover, some common amplifications, such as that at 8p11-12 in breast cancer, harbor multiple driver oncogenes, which are poorly modeled by conventional overexpression approaches. We sought to develop an experimental system to model recurrent chromosomal amplification events in human cell lines. Our strategy is to use homologous-recombination-mediated gene targeting to deliver a dominantly selectable, amplifiable marker to a specified chromosomal location. We used adeno-associated virus vectors to target human MCF-7 breast cancer cells at the ZNF703 locus, in the recurrent 8p11-12 amplicon, using the E. coli inosine monophosphate dehydrogenase (IMPDH) enzyme as a marker. We applied selective pressure using IMPDH inhibitors. Surviving clones were found to have increased copy number of ZNF703 (average 2.5-fold increase) by droplet digital PCR and FISH. Genome-wide array comparative genomic hybridization confirmed that amplifications had occurred on the short arm of chromosome 8, without changes on 8q or other chromosomes. Patterns of amplification were variable and similar to those seen in primary human breast cancers, including "sawtooth" patterns, distal copy number loss, and large continuous regions of copy number gain. This system will allow study of the cis- and trans-acting factors that are permissive for chromosomal amplification and provide a model to analyze oncogene cooperativity in amplifications harboring multiple candidate driver genes.

  5. Studies on the integration of hepatitis B virusDNA sequence in human sperm chromosomes

    Institute of Scientific and Technical Information of China (English)

    Jian-MinHUANG; Tian-HuaHUANG

    2002-01-01

    Aim:To study the integration of hepatitis Bvirus(HBV)DNAinto sperm chromosomes in hepatitsBpatients and the features of its integration.Methods:Sperm chromosomes of 14subjects(5healthy controls and9HBpatients,including1acute hepatitis B,2chronic active hepatitisB,4chronic persistent hepatitsB,2HBsAg chronic carriers with no clinical symptoms)were prepared using imterspecific in vitro fertilization between zona-free hamster oocytes and human spermatozoa.Fluosescence in situ hybridization(FISH)to sperm chromosome spreads was carried out with biotin-labeled full length HBVDNAprobe to detect the specificHBVDNA sequences in the sperm chromosomes.Results:Specific fluorescent signal spots for HBVDNAwere seen iv sperm chromosomes of one patient with chronic persistent hepatitisB.In9(9/42)sperm chromosome complements containing fluorescent signal spots,one presented5obvious FISHspots and the others2to4signals.The fluorescence intensity showed significant difference among the signal spots.The distribution of signal sites among chromosomes seems to be random.Con clusion:HBV could integrate into human sperm chromosomes.Results suggest that the possibility of vertical transmission of HBVvia the germ line tothe next generation is present.

  6. Interference in DNA replication can cause mitotic chromosomal breakage unassociated with double-strand breaks.

    Directory of Open Access Journals (Sweden)

    Mari Fujita

    Full Text Available Morphological analysis of mitotic chromosomes is used to detect mutagenic chemical compounds and to estimate the dose of ionizing radiation to be administered. It has long been believed that chromosomal breaks are always associated with double-strand breaks (DSBs. We here provide compelling evidence against this canonical theory. We employed a genetic approach using two cell lines, chicken DT40 and human Nalm-6. We measured the number of chromosomal breaks induced by three replication-blocking agents (aphidicolin, 5-fluorouracil, and hydroxyurea in DSB-repair-proficient wild-type cells and cells deficient in both homologous recombination and nonhomologous end-joining (the two major DSB-repair pathways. Exposure of cells to the three replication-blocking agents for at least two cell cycles resulted in comparable numbers of chromosomal breaks for RAD54(-/-/KU70(-/- DT40 clones and wild-type cells. Likewise, the numbers of chromosomal breaks induced in RAD54(-/-/LIG4(-/- Nalm-6 clones and wild-type cells were also comparable. These data indicate that the replication-blocking agents can cause chromosomal breaks unassociated with DSBs. In contrast with DSB-repair-deficient cells, chicken DT40 cells deficient in PIF1 or ATRIP, which molecules contribute to the completion of DNA replication, displayed higher numbers of mitotic chromosomal breaks induced by aphidicolin than did wild-type cells, suggesting that single-strand gaps left unreplicated may result in mitotic chromosomal breaks.

  7. Identical functional organization of nonpolytene and polytene chromosomes in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Tatyana Yu Vatolina

    Full Text Available Salivary gland polytene chromosomes demonstrate banding pattern, genetic meaning of which is an enigma for decades. Till now it is not known how to mark the band/interband borders on physical map of DNA and structures of polytene chromosomes are not characterized in molecular and genetic terms. It is not known either similar banding pattern exists in chromosomes of regular diploid mitotically dividing nonpolytene cells. Using the newly developed approach permitting to identify the interband material and localization data of interband-specific proteins from modENCODE and other genome-wide projects, we identify physical limits of bands and interbands in small cytological region 9F13-10B3 of the X chromosome in D. melanogaster, as well as characterize their general molecular features. Our results suggests that the polytene and interphase cell line chromosomes have practically the same patterns of bands and interbands reflecting, probably, the basic principle of interphase chromosome organization. Two types of bands have been described in chromosomes, early and late-replicating, which differ in many aspects of their protein and genetic content. As appeared, origin recognition complexes are located almost totally in the interbands of chromosomes.

  8. Chromosome-specific families in Vibrio genomes

    Directory of Open Access Journals (Sweden)

    Oksana eLukjancenko

    2014-03-01

    Full Text Available We have compared chromosome-specific genes in a set of 18 finished Vibrio genomes, and, in addition, also calculated the pan- and core-genomes from a data set of more than 250 draft Vibrio genome sequences. These genomes come from 9 known species and 2 unknown species. Within the finished chromosomes, we find a core set of 1269 encoded protein families for chromosome 1, and a core of 252 encoded protein families for chromosome 2. Many of these core proteins are also found in the draft genomes (although which chromosome they are located on is unknown. Of the chromosome specific core protein families, 1169 and 153 are uniquely found in chromosomes 1 and 2, respectively. Gene ontology (GO terms for each of the protein families were determined, and the different sets for each chromosome were compared. A total of 363 different `Molecular Function` GO categories were found for chromosome 1 specific protein families, and these include several broad activities: pyridoxine 5' phosphate synthetase, glucosylceramidase, heme transport, DNA ligase, amino acid binding, and ribosomal components; in contrast, chromosome 2 specific protein families have only 66 Molecular Function GO terms and include many membrane-associated activities, such as ion channels, transmembrane transporters, and electron transport chain proteins. Thus, it appears that whilst there are many 'housekeeping systems' encoded in chromosome 1, there are far fewer core functions found in chromosome 2. However, the presence of many membrane-associated encoded proteins in chromosome 2 is surprising.

  9. No Substitute Teacher Left behind

    Science.gov (United States)

    O'Connor, Kevin

    2009-01-01

    Schools and districts routinely recruit, retain, and support highly qualified teachers to ensure that students receive the best learning opportunities. However, even if one's school employs highly qualified full-time teachers, it is important to acknowledge that substitute teachers also have a significant impact on the education of students. One…

  10. Tax Rates as Strategic Substitutes

    NARCIS (Netherlands)

    R.A. de Mooij (Ruud); H. Vrijburg (Hendrik)

    2012-01-01

    textabstractThis paper analytically derives the conditions under which the slope of the tax reaction function is negative in a classical tax competition model. If countries maximize welfare, we show that a negative slope (reflecting strategic substitutability) occurs under relatively mild conditions

  11. Tax rates as strategic substitutes

    NARCIS (Netherlands)

    H. Vrijburg (Hendrik); R.A. de Mooij (Ruud)

    2016-01-01

    textabstractThis paper analytically derives conditions under which the slope of the tax-reaction function is negative in a classical tax competition model. If countries maximize welfare, a negative slope (reflecting strategic substitutability) occurs under relatively mild conditions. The strategic t

  12. A comparison of male and female recombination frequency in wheat using RFLP maps of homoeologous group 6 and 7 chromosomes.

    Science.gov (United States)

    Wang, G; Hyne, V; Chao, S; Gale, M D; Henry, Y; De Buyser, J; Snape, J W

    1995-10-01

    A novel approach was used to compare male and female recombination rates in wheat. Doubled haploid lines were developed from an F1 using two distinct approaches: the anther-culture technique and the Hordeum bulbosum system, from which sets of lines were developed from "male" and "female" meioses, respectively. The genotype of the lines was established at RFLP and isozyme markers polymorphic on chromosomes of homoeologous groups 6 and 7, and "male" and "female" linkage maps were calculated using this information. The markers in one segment of chromosome 6B exhibited disturbed segregation frequencies in the anther-culture population. The "male" and "female" maps differed significantly in recombination frequency between some markers on two chromosomes, and these were consistent in direction within chromosomes and inconsistent in direction between chromosomes. In two of the four chromosomes studied the "male" map was much longer than the "female" map. These results suggest that significant differences may exist in male and female recombination frequencies in bread wheat which are specific to certain chromosomal segments but are inconsistent in direction between chromosomes. Other factors, such as environmental influences, may also be important in creating differences.

  13. The Evolutionary Tempo of Sex Chromosome Degradation in Carica papaya.

    Science.gov (United States)

    Wu, Meng; Moore, Richard C

    2015-06-01

    Genes on non-recombining heterogametic sex chromosomes may degrade over time through the irreversible accumulation of deleterious mutations. In papaya, the non-recombining male-specific region of the Y (MSY) consists of two evolutionary strata corresponding to chromosomal inversions occurring approximately 7.0 and 1.9 MYA. The step-wise recombination suppression between the papaya X and Y allows for a temporal examination of the degeneration progress of the young Y chromosome. Comparative evolutionary analyses of 55 X/Y gene pairs showed that Y-linked genes have more unfavorable substitutions than X-linked genes. However, this asymmetric evolutionary pattern is confined to the oldest stratum, and is only observed when recently evolved pseudogenes are included in the analysis, indicating a slow degeneration tempo of the papaya Y chromosome. Population genetic analyses of coding sequence variation of six Y-linked focal loci in the oldest evolutionary stratum detected an excess of nonsynonymous polymorphism and reduced codon bias relative to autosomal loci. However, this pattern was also observed for corresponding X-linked loci. Both the MSY and its corresponding X-specific region are pericentromeric where recombination has been shown to be greatly reduced. Like the MSY region, overall selective efficacy on the X-specific region may be reduced due to the interference of selective forces between highly linked loci, or the Hill-Robertson effect, that is accentuated in regions of low or suppressed recombination. Thus, a pattern of gene decay on the X-specific region may be explained by relaxed purifying selection and widespread genetic hitchhiking due to its pericentromeric location.

  14. Development of a platform for breeding by design of CMS restorer lines based on an SSSL library in rice (Oryza sativa L.).

    Science.gov (United States)

    Dai, Ziju; Lu, Qing; Luan, Xin; Ouyang, Lian; Guo, Jie; Liang, Jiayan; Zhu, Haitao; Wang, Wenjuan; Wang, Shaokui; Zeng, Ruizhen; Liu, Ziqiang; Zhang, Zemin; Zhu, Xiaoyuan; Zhang, Guiquan

    2016-12-01

    Exploitation of the heterosis of hybrid rice has shown great success in the improvement of rice yields. However, few genotypes exhibit strong restoration ability as effective restorers of cytoplasmic male sterility (CMS) in the development of hybrid rice. In this study, we developed a platform for the breeding by design of CMS restorer lines based on a library of chromosomal single segment substitution lines (SSSLs) in the Huajingxian74 (HJX74) genetic background. The target genes for breeding by design, Rf3(4) and Rf4(4), which are associated with a strong restoration ability, and gs3, gw8, Wx(g1) and Alk, which are associated with good grain quality, were selected from the HJX74 SSSL library. Through pyramiding of the target genes, a restorer line, H121R, was developed. The H121R line was then improved regarding blast resistance by pyramiding of the qBLAST11 gene. Hence, a new restorer line with blast resistance, H131R, was developed. The platform involving the Rf3(4) and Rf4(4) restorer genes would be used for the continuous improvement of restorer lines through breeding by design in rice.

  15. Sex chromosome rearrangements in Polyphaga beetles.

    Science.gov (United States)

    Dutrillaux, A M; Dutrillaux, B

    2009-01-01

    The presence of a parachute sex chromosome bivalent (Xyp) at metaphase I of male meiosis is a well-known characteristic of Coleoptera, present in almost all families of this order and assumed to represent their ancestral sex chromosome formula. Sex chromosomes appear to be manifold more frequently involved in inter-chromosomal rearrangements than the average of the nine autosomal pairs usually forming their karyotype. This leads to various formulae such as neo-sex, multiple sex and perhaps unique sex chromosomes. These rearrangements alter the intimate association between sex chromosomes and nucleolar proteins, which are usual components of the Xyp. Different situations, selected in a series of 125 mitotic and meiotic cytogenetic studies of Polyphaga beetle species, are reported and discussed, with the aim to improve our knowledge on the mechanisms of sex chromosome rearrangements, the relationships with nucleoli and the consequences on dosage compensation and chromosome segregation.

  16. Vibrio chromosome-specific families

    DEFF Research Database (Denmark)

    Lukjancenko, Oksana; Ussery, David

    2014-01-01

    We have compared chromosome-specific genes in a set of 18 finished Vibrio genomes, and, in addition, also calculated the pan- and core-genomes from a data set of more than 250 draft Vibrio genome sequences. These genomes come from 9 known species and 2 unknown species. Within the finished...

  17. Chromosome Territory Modeller and Viewer.

    Science.gov (United States)

    Tkacz, Magdalena A; Chromiński, Kornel; Idziak-Helmcke, Dominika; Robaszkiewicz, Ewa; Hasterok, Robert

    2016-01-01

    This paper presents ChroTeMo, a tool for chromosome territory modelling, accompanied by ChroTeVi-a chromosome territory visualisation software that uses the data obtained by ChroTeMo. These tools have been developed in order to complement the molecular cytogenetic research of interphase nucleus structure in a model grass Brachypodium distachyon. Although the modelling tool has been initially created for one particular species, it has universal application. The proposed version of ChroTeMo allows for generating a model of chromosome territory distribution in any given plant or animal species after setting the initial, species-specific parameters. ChroTeMo has been developed as a fully probabilistic modeller. Due to this feature, the comparison between the experimental data on the structure of a nucleus and the results obtained from ChroTeMo can indicate whether the distribution of chromosomes inside a nucleus is also fully probabilistic or is subjected to certain non-random patterns. The presented tools have been written in Python, so they are multiplatform, portable and easy to read. Moreover, if necessary they can be further developed by users writing their portions of code. The source code, documentation, and wiki, as well as the issue tracker and the list of related articles that use ChroTeMo and ChroTeVi, are accessible in a public repository at Github under GPL 3.0 license.

  18. CHROMOSOMAL MULTIPLICITY IN BURKHOLDERIA CEPACIA

    Science.gov (United States)

    We have used CHEF gel electrophoresis to screen preparations of large DNA from different Burkholderia cepacia isolates for the presence of DNA species corresponding to the linearized forms of the three chromosomes of 3.4,2.5, and 0.9 Mb identified in B. cepacia strain 17616. DNA ...

  19. Chromosome synteny in cucumis species

    Science.gov (United States)

    Cucumber, Cucumis sativus L. (2n = 2x = 14) and melon, C. melo L. (2n = 2x = 24) are two important vegetable species in the genus Cucumis (family Cucurbitaceae). Two inter-fertile botanical varieties with 14 chromosomes, the cultivated C. sativus var. sativus L. and the wild C. sativus var. hardwick...

  20. Chromosomal disorders and male infertility

    Institute of Scientific and Technical Information of China (English)

    Gary L Harton; Helen G Tempest

    2012-01-01

    infertility in humans is surprisingly common occurring in approximately 15% of the population wishing to start a family.Despite this,the molecular and genetic factors underlying the cause of infertility remain largely undiscovered.Nevertheless,more and more genetic factors associated with infertility are being identified.This review will focus on our current understanding of the chromosomal basis of male infertility specifically:chromosomal aneuploidy,structural and numerical karyotype abnormalities and Y chromosomal microdeletions.Chromosomal aneuploidy is the leading cause of pregnancy loss and developmental disabilities in humans.Aneuploidy is predominantly maternal in origin,but concerns have been raised regarding the safety of intracytoplasmic sperm injection as infertile men have significantly higher levels of sperm aneuploidy compared to their fertile counterparts.Males with numerical or structural karyotype abnormalities are also at an increased risk of producing aneuploid sperm.Our current understanding of how sperm aneuploidy translates to embryo aneuploidy will be reviewed,as well as the application of preimplantation genetic diagnosis (PGD) in such cases.Clinical recommendations where possible will be made,as well as discussion of the use of emerging array technology in PGD and its potential applications in male infertility.

  1. Molecular cytogenetic analysis of dicentric chromosomes in acute myeloid leukemia.

    Science.gov (United States)

    Sarova, Iveta; Brezinova, Jana; Zemanova, Zuzana; Ransdorfova, Sarka; Izakova, Silvia; Svobodova, Karla; Pavlistova, Lenka; Berkova, Adela; Cermak, Jaroslav; Jonasova, Anna; Siskova, Magda; Michalova, Kyra

    2016-04-01

    Dicentric chromosomes (DCs) have been described in many hematological diseases, including acute myeloid leukemia (AML). They are markers of cancer and induce chromosomal instability, leading to the formation of other chromosomal aberrations and the clonal evolution of pathological cells. Our knowledge of the roles and behavior of human DCs is often derived from studies of induced DCs and cell lines. It is difficult to identify all the DCs in the karyotypes of patients because of the limitations of metaphase cytogenetic methods. The aim of this study was to revise the karyotypes of 20 AML patients in whom DCs were found with conventional G-banding or multicolor fluorescence in situ hybridization (mFISH) with (multi)centromeric probes and to characterize the DCs at the molecular cytogenetic level. FISH analyses confirmed 23 of the 29 expected DCs in 18 of 20 patients and identified 13 others that had not been detected cytogenetically. Fourteen DCs were altered by other chromosomal changes. In conclusion, karyotypes with DCs are usually very complex, and we have shown that they often contain more than one DC, which can be missed with conventional or mFISH methods. Our study indicates an association between number of DCs in karyotype and very short survival of patients.

  2. A Plain English Map of the Human Chromosomes.

    Science.gov (United States)

    Offner, Susan

    1992-01-01

    Presents a chromosome map for 19 known chromosomes in human genetics. Describes the characteristics attributed to the genetic codes for each of the chromosomes and discusses the teaching applications of the chromosome map. (MDH)

  3. Familial transmission of a ring chromosome 21

    DEFF Research Database (Denmark)

    Hertz, Jens Michael

    1987-01-01

    A ring chromosome 21 was found in a phenotypically normal mother and her son. The clinical findings in the son were bilateral retention of the testes and a slightly delayed puberty onset. Consequences of a ring formation of a chromosome 21 in phenotypically normal patients are presented...... and discussed, and the previously reported cases of familially transmitted G-group ring chromosomes are reviewed....

  4. Female meiotic sex chromosome inactivation in chicken

    NARCIS (Netherlands)

    S. Schoenmakers (Sam); E. Wassenaar (Evelyne); J.W. Hoogerbrugge (Jos); J.S.E. Laven (Joop); J.A. Grootegoed (Anton); W.M. Baarends (Willy)

    2009-01-01

    textabstractDuring meiotic prophase in male mammals, the heterologous X and Y chromosomes remain largely unsynapsed, and meiotic sex chromosome inactivation (MSCI) leads to formation of the transcriptionally silenced XY body. In birds, the heterogametic sex is female, carrying Z and W chromosomes (Z

  5. Altered chromosome 6 in immortal human fibroblasts.

    Science.gov (United States)

    Hubbard-Smith, K; Patsalis, P; Pardinas, J R; Jha, K K; Henderson, A S; Ozer, H L

    1992-05-01

    Human diploid fibroblasts have a limited life span in vitro, and spontaneous immortalization is an extremely rare event. We have used transformation of human diploid fibroblasts by an origin-defective simian virus 40 genome to develop series of genetically matched immortal cell lines to analyze immortalization. Comparison of a preimmortal transformant (SVtsA/HF-A) with its uncloned and cloned immortalized derivatives (AR5 and HAL) has failed to reveal any major alteration involving the simian virus 40 genome. Karyotypic analysis, however, demonstrated that all of the immortal cell lines in this series have alterations of chromosome 6 involving loss of the portion distal to 6q21. The karyotypic analysis was corroborated by DNA analyses. Southern analysis demonstrated that only one copy of three proto-oncogene loci (ros1, c-myb, and mas1) on 6q was retained in immortal cells. Polymerase chain reaction analysis of the microsatellite polymorphism at 6q22 (D6S87) showed loss of heterozygosity. In addition, elevated expression of c-myb (6q22-23) was observed. We hypothesize that the region at and/or distal to 6q21 plays a role in immortalization, consistent with the presence of a growth suppressor gene.

  6. Altered chromosome 6 in immortal human fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard-Smith, K.; Pardinas, J.R.; Jha, K.K.; Ozer, H.L. (New Jersey Medical School, Newark, NJ (United States)); Patsalis, P.; Henderson, A.S. (City Univ. of New York, NY (United States))

    1992-05-01

    Human diploid fibroblasts have a limited life span in vitro, and spontaneous immortalization is an extremely rare event. We have used transformation of human diploid fibroblasts by an origin-defective simian virus 40 genome to develop series of genetically matched immortal cell lines to analyze immortalization. Comparison of a preimmortal transformant (SVtsA/HF-A) with its uncloned and cloned immortalized derivatives (AR5 and HAL) has failed to reveal any major alteration involving the simian virus 40 genome. Karyotypic analysis, however, demonstrated that all of the immortal cell lines in this series have alterations of chromosome 6 involving loss of the portion distal to 6q21. The karyotypic analysis was corroborated by DNA analyses. Southern analysis demonstrated that only one copy of three proto-oncogene loci (ros1, c-myb, and mas1) on 6q was retained in immortal cells. Polymerase chain reaction analysis of the microsatellite polymorphism at 6q22 (D6S87) showed loss of heterozygosity. In addition, elevated expression of c-myb (6q22-23) was observed. We hypothesize that the region at and/or distal to 6q21 plays a role in immortalization, consistent with the presence of a growth suppressor gene. 66 refs., 6 figs., 2 tabs.

  7. Effects on Genome Constitution and Novel Cell Wall Formation Caused by the Addition of 5RS Rye Chromosome to Common Wheat

    Institute of Scientific and Technical Information of China (English)

    Zhi-Jun Cheng; Minoru Murata; Sodmergen; Xiao-Mei Li; Hai Nian; Jian-Min Wan

    2008-01-01

    The cytological instability of common wheat-rye addition lines was investigated in the present study. The chromosome numbers of almost all addition lines were considerably stable, but those of CS + 5R were very variable. The rye chromosome added in this line was found to be much shorter than expected. Fluorescent in situ hybridization with 5S rDNA and the centromere-specific probes clearly revealed that the short rye chromosome contains only a short arm of chromosome 5R (5RS). In this line, chromosome numbers of both 5RS and common wheat were changeable. The chromosome numbers ranged from 2n = 36 to 2n = 44 in the cells carrying two 5RS, and ranged from 2n = 31 to 2n = 44 in one 5RS cells. In addition to the chromosome instability, the multicells wrapped in a sac-like structure were frequently observed in the root meristematic tissues of CS + 5RS after the enzyme treatment for chromosome preparation. Genomic in situ hybridization with rye DNA as a probe showed that all cells in sacs investigated were at the interphase stage and contained one or two 5RS chromosomes. An electron microscopic analysis revealed that the cells of CS + 5RS, particularly in sacs, have abnormal (irregular and curved) cell walls. These results indicate that 5RS has (a) specific factor(s) influencing the cell wall development as well as the genome stability.

  8. Plasticity in the Meiotic Epigenetic Landscape of Sex Chromosomes in Caenorhabditis Species.

    Science.gov (United States)

    Larson, Braden J; Van, Mike V; Nakayama, Taylor; Engebrecht, JoAnne

    2016-08-01

    During meiosis in the heterogametic sex in some species, sex chromosomes undergo meiotic sex chromosome inactivation (MSCI), which results in acquisition of repressive chromatin and transcriptional silencing. In Caenorhabditis elegans, MSCI is mediated by MET-2 methyltransferase deposition of histone H3 lysine 9 dimethylation. Here we examined the meiotic chromatin landscape in germ lines of four Caenorhabditis species; C. remanei and C. brenneri represent ancestral gonochorism, while C. briggsae and C. elegans are two lineages that independently evolved hermaphroditism. While MSCI is conserved across all four species, repressive chromatin modifications are distinct and do not correlate with reproductive mode. In contrast to C. elegans and C. remanei germ cells where X chromosomes are enriched for histone H3 lysine 9 dimethylation, X chromosomes in C. briggsae and C. brenneri germ cells are enriched for histone H3 lysine 9 trimethylation. Inactivation of C. briggsae MET-2 resulted in germ-line X chromosome transcription and checkpoint activation. Further, both histone H3 lysine 9 di- and trimethylation were reduced in Cbr-met-2 mutant germ lines, suggesting that in contrast to C. elegans, H3 lysine 9 di- and trimethylation are interdependent. C. briggsae H3 lysine 9 trimethylation was redistributed in the presence of asynapsed chromosomes in a sex-specific manner in the related process of meiotic silencing of unsynapsed chromatin. However, these repressive marks did not influence X chromosome replication timing. Examination of additional Caenorhabditis species revealed diverse H3 lysine 9 methylation patterns on the X, suggesting that the sex chromosome epigenome evolves rapidly.

  9. Substitute Students Do a Roaring Trade

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    UniverSity students employ substitutes for a wide range of duties, from attending compulsory morning exercises and classes to writing papers or even love letters, These substitutes advertise their services on campus bulletin boards,

  10. An E2-Substituted Chimeric Pestivirus With DIVA Vaccine Properties

    DEFF Research Database (Denmark)

    Rasmussen, Thomas Bruun; Uttenthal, Åse; Nielsen, Jens

    An advantage of the use of chimeric pestiviruses as modified live vaccines against classical swine fever (CSF) resides in their capacity to be manipulated to achieve the characteristics desired for safe and efficacious DIVA vaccines. We have recently generated a new chimeric virus, Riems26_E2gif...... engineered specifically for this purpose. The E2-substituted Riems26_E2gif was derived by homologues recombination of the complete E2 protein encoding genome region from Border disease strain Gifhorn into a bacterial artificial chromosome (BAC) harbouring the genome of the CSFV vaccine strain C......-Riems. The virulence, immunogenicity and vaccine properties of Riems26_E2gif were tested in a vaccine-challenge experiment in pigs. Riems26_E2gif vaccinated pigs could be differentiated from infected pigs using a CSFV-E2 specific ELISA. Following challenge infection with highly virulent CSFV strain Koslov, all...

  11. The origin of human chromosome 2 analyzed by comparative chromosome mapping with a DNA microlibrary

    OpenAIRE

    Wienberg, Johannes; Jauch, Anna; Lüdecke, H J; Senger, G.; Horsthemke, B; Claussen, U.; Cremer, Thomas; Arnold, N; Lengauer, Christoph

    1994-01-01

    Fluorescencein situ hybridization (FISH) of microlibraries established from distinct chromosome subregions can test the evolutionary conservation of chromosome bands as well as chromosomal rearrangements that occurred during primate evolution and will help to clarify phylogenetic relationships. We used a DNA library established by microdissection and microcloning from the entire long arm of human chromosome 2 for fluorescencein situ hybridization and comparative mapping of the chromosomes of ...

  12. Chromosomal instability in Streptomyces avermitilis: major deletion in the central region and stable circularized chromosome

    Directory of Open Access Journals (Sweden)

    Wen Ying

    2010-07-01

    Full Text Available Abstract Background The chromosome of Streptomyces has been shown to be unstable, frequently undergoing gross chromosomal rearrangements. However, the mechanisms underlying this phenomenon remain unclear, with previous studies focused on two chromosomal ends as targets for rearrangements. Here we investigated chromosomal instability of Streptomyces avermitilis, an important producer of avermectins, and characterized four gross chromosomal rearrangement events, including a major deletion in the central region. The present findings provide a valuable contribution to the mechanistic study of genetic instability in Streptomyces. Results Thirty randomly-selected "bald" mutants derived from the wild-type strain all contained gross chromosomal rearrangements of various types. One of the bald mutants, SA1-8, had the same linear chromosomal structure as the high avermectin-producing mutant 76-9. Chromosomes of both strains displayed at least three independent chromosomal rearrangements, including chromosomal arm replacement to form new 88-kb terminal inverted repeats (TIRs, and two major deletions. One of the deletions eliminated the 36-kb central region of the chromosome, but surprisingly did not affect viability of the cells. The other deletion (74-kb was internal to the right chromosomal arm. The chromosome of another bald mutant, SA1-6, was circularized with deletions at both ends. No obvious homology was found in all fusion sequences. Generational stability analysis showed that the chromosomal structure of SA1-8 and SA1-6 was stable. Conclusions Various chromosomal rearrangements, including chromosomal arm replacement, interstitial deletions and chromosomal circularization, occurred in S. avermitilis by non-homologous recombination. The finding of an inner deletion involving in the central region of S. avermitilis chromosome suggests that the entire Streptomyces chromosome may be the target for rearrangements, which are not limited, as previously

  13. Smart Phones and their Substitutes

    DEFF Research Database (Denmark)

    Bødker, Mads; Gimpel, Gregory; Hedman, Jonas

    2009-01-01

    Drawing on data from a longitudinal field study, this paper investigates the influence of existing, better and stand-alone technology substitutes on the use of smart phones. By applying prospect theory, media richness theory, and business model literature, the purpose of this paper is to improve...... our understanding of the role of substitutes, device content fit issues, and implications for business models by asking the question: What is an effective business model to address the relationship between user preference and the fit of the smart phone and everyday task? The field study data suggest...... the need for business models to recognize that adoption decisions are reference-dependent and strongly influenced by the fit between task and smart phone....

  14. Commercial formalin substitutes for histopathology

    DEFF Research Database (Denmark)

    Prentø, P; Lyon, H

    1997-01-01

    of protein and structural immobilization, quality of histology and cellular structure following routine dehydration and paraffin embedding, and performance as a fixative for immunohistochemistry. Furthermore, we evaluated the effects of the various fixatives on ultrastructure. Only buffered formalin......We compared the performance of six commercial fixatives proposed to be formalin substitutes with the performance of buffered formalin, Clarke's ethanol-acetic acid, and ethanol, using rat liver, small intestine, and kidney. We investigated the rate of penetration, mode of fixation, extent...... performed equally well on all tissues tested. While several of the commercial fixatives appeared to preserve liver tissue at 200x, the preservation of kidney, intestinal villi, and smooth muscle was unacceptable. Histological distortion, cell shrinkage and vacuolization were prominent when the substitutes...

  15. Y-chromosome polymorphism: Possible largest Y chromosome in man?

    Energy Technology Data Exchange (ETDEWEB)

    Murthy, D.S.K.; Al-Awadi, S.A.; Bastaki, L. [Kuwait Medical Genetics Centre, Sulaibikat (Kuwait)] [and others

    1994-09-01

    The role of variations (inversions/deletion or duplication) in the heterochromatin in gonadal development and function, reproductive fitness, and malignant disease has been extensively studied. However, the causal-relationship of large Y (Yqh+) and repeated fetal loss has not been established unequivocally. An Arab couple (?Bedouin origin) with a history of repeated abortions were investigated. Karyotype analysis of the husband showed a very large Y chromosome, confirmed by GTG-, QFQ- and CBG-banding techniques. C-banding showed discontinuous distribution of the heterochromatin blocks separated by pale bands. The origin of the large heterochromatin segment could be due to tandem duplication of the Yq region or translocation (Yq:Yq). No other relatives (males) of the propositus have been available for investigation. Polymorphism of the Y chromosome could be attributed to evolutionary changes from an ancestral type, either by deletion or duplication of the heterochromatin segment. More detailed studies on isolated, aboriginal/tribal human populations will enable us to better understand the significance of the Y chromosome polymorphism.

  16. Screening and incorporation of rust resistance from Allium cepa into bunching onion (Allium fistulosum) via alien chromosome addition.

    Science.gov (United States)

    Wako, Tadayuki; Yamashita, Ken-ichiro; Tsukazaki, Hikaru; Ohara, Takayoshi; Kojima, Akio; Yaguchi, Shigenori; Shimazaki, Satoshi; Midorikawa, Naoko; Sakai, Takako; Yamauchi, Naoki; Shigyo, Masayoshi

    2015-04-01

    Bunching onion (Allium fistulosum L.; 2n = 16), bulb onion (Allium cepa L. Common onion group), and shallot (Allium cepa L. Aggregatum group) cultivars were inoculated with rust fungus, Puccinia allii, isolated from bunching onion. Bulb onions and shallots are highly resistant to rust, suggesting they would serve as useful resources for breeding rust resistant bunching onions. To identify the A. cepa chromosome(s) related to rust resistance, a complete set of eight A. fistulosum - shallot monosomic alien addition lines (MAALs) were inoculated with P. allii. At the seedling stage, FF+1A showed a high level of resistance in controlled-environment experiments, suggesting that the genes related to rust resistance could be located on shallot chromosome 1A. While MAAL, multi-chromosome addition line, and hypoallotriploid adult plants did not exhibit strong resistance to rust. In contrast to the high resistance of shallot, the addition line FF+1A+5A showed reproducibly high levels of rust resistance.

  17. Sexual differentiation in the developing mouse brain: contributions of sex chromosome genes.

    Science.gov (United States)

    Wolstenholme, J T; Rissman, E F; Bekiranov, S

    2013-03-01

    Neural sexual differentiation begins during embryogenesis and continues after birth for a variable amount of time depending on the species and brain region. Because gonadal hormones were the first factors identified in neural sexual differentiation, their role in this process has eclipsed investigation of other factors. Here, we use a mouse with a spontaneous translocation that produces four different unique sets of sex chromosomes. Each genotype has one normal X-chromosome and a unique second sex chromosome creating the following genotypes: XY(*x) , XX, XY(*) , XX(Y) (*) . This Y(*) mouse line is used by several laboratories to study two human aneuploid conditions: Turner and Klinefelter syndromes. As sex chromosome number affects behavior and brain morphology, we surveyed brain gene expression at embryonic days 11.5 and 18.5 to isolate X-chromosome dose effects in the developing brain as possible mechanistic changes underlying the phenotypes. We compared gene expression differences between gonadal males and females as well as individuals with one vs. two X-chromosomes. We present data showing, in addition to genes reported to escape X-inactivation, a number of autosomal genes are differentially expressed between the sexes and in mice with different numbers of X-chromosomes. Based on our results, we can now identify the genes present in the region around the chromosomal break point that produces the Y(*) model. Our results also indicate an interaction between gonadal development and sex chromosome number that could further elucidate the role of sex chromosome genes and hormones in the sexual differentiation of behavior.

  18. Substituted Indoleacetic Acids Tested in Tissue Cultures

    DEFF Research Database (Denmark)

    Engvild, Kjeld Christensen

    1978-01-01

    Monochloro substituted IAA inhibited shoot induction in tobacco tissue cultures about as much as IAA. Dichloro substituted IAA inhibited shoot formation less. Other substituted IAA except 5-fluoro- and 5-bromoindole-3-acetic acid were less active than IAA. Callus growth was quite variable...

  19. 40 CFR 721.9820 - Substituted triazole.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted triazole. 721.9820 Section... Substances § 721.9820 Substituted triazole. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance generically identified as a substituted triazole (PMN P-90-1731)...

  20. Substitution reactions at boron atoms in metallacarboranes

    Energy Technology Data Exchange (ETDEWEB)

    Bregadze, Vladimir I; Timofeev, Sergei V; Sivaev, Igor B; Lobanova, Irina A [A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow (Russian Federation)

    2004-05-31

    Data on substitution reactions at boron atoms in 10-12-vertex metallacarboranes, which are of fundamental and applied significance, are generalised. The possible mechanisms of substitution reactions and the influence of the metal fragment on substitution positions in the polyhedron are discussed.

  1. 24 CFR 220.253 - Substitute mortgagors.

    Science.gov (United States)

    2010-04-01

    ... Contract Rights and Obligations-Homes § 220.253 Substitute mortgagors. (a) Selling mortgagor. The mortgagee... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Substitute mortgagors. 220.253... the Commissioner's approval of a substitute mortgagor, as provided by this section. (b)...

  2. 24 CFR 221.252 - Substitute mortgagors.

    Science.gov (United States)

    2010-04-01

    ... Cost Homes § 221.252 Substitute mortgagors. (a) Selling mortgagor. The mortgagee may effect the release... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Substitute mortgagors. 221.252... approval of a substitute mortgagor, as provided by this section. (b) Purchasing mortgagor. The...

  3. 40 CFR 721.5867 - Substituted phenol.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted phenol. 721.5867 Section... Substances § 721.5867 Substituted phenol. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance generically identified as substituted phenol (PMNs P-89-1125,...

  4. 40 CFR 721.8775 - Substituted pyridines.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted pyridines. 721.8775... Substances § 721.8775 Substituted pyridines. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted pyridine (PMN P-84-1219)...

  5. Chromosome congression explained by nanoscale electrostatics.

    Science.gov (United States)

    Gagliardi, L John; Shain, Daniel H

    2014-02-24

    Nanoscale electrostatic microtubule disassembly forces between positively charged molecules in kinetochores and negative charges on plus ends of microtubules have been implicated in poleward chromosome motions and may also contribute to antipoleward chromosome movements. We propose that chromosome congression can be understood in terms of antipoleward nanoscale electrostatic microtubule assembly forces between negatively charged microtubule plus ends and like-charged chromosome arms, acting in conjunction with poleward microtubule disassembly forces. Several other aspects of post-attachment prometaphase chromosome motions, as well as metaphase oscillations, are consistently explained within this framework.

  6. The Chromosomes of Birds during Meiosis.

    Science.gov (United States)

    Pigozzi, María I

    2016-01-01

    The cytological analysis of meiotic chromosomes is an exceptional tool to approach complex processes such as synapsis and recombination during the division. Chromosome studies of meiosis have been especially valuable in birds, where naturally occurring mutants or experimental knock-out animals are not available to fully investigate the basic mechanisms of major meiotic events. This review highlights the main contributions of synaptonemal complex and lampbrush chromosome research to the current knowledge of avian meiosis, with special emphasis on the organization of chromosomes during prophase I, the impact of chromosome rearrangements during meiosis, and distinctive features of the ZW pair.

  7. Polymer models of chromosome (re)organization

    Science.gov (United States)

    Mirny, Leonid

    Chromosome Conformation Capture technique (Hi-C) provides comprehensive information about frequencies of spatial interactions between genomic loci. Inferring 3D organization of chromosomes from these data is a challenging biophysical problem. We develop a top-down approach to biophysical modeling of chromosomes. Starting with a minimal set of biologically motivated interactions we build ensembles of polymer conformations that can reproduce major features observed in Hi-C experiments. I will present our work on modeling organization of human metaphase and interphase chromosomes. Our works suggests that active processes of loop extrusion can be a universal mechanism responsible for formation of domains in interphase and chromosome compaction in metaphase.

  8. Iridium-Catalyzed Allylic Substitution

    Science.gov (United States)

    Hartwig, John F.; Pouy, Mark J.

    Iridium-catalyzed asymmetric allylic substitution has become a valuable method to prepare products from the addition of nucleophiles at the more substituted carbon of an allyl unit. The most active and selective catalysts contain a phosphoramidite ligand possessing at least one arylethyl substituent on the nitrogen atom of the ligand. In these systems, the active catalyst is generated by a base-induced cyclometalation at the methyl group of this substituent to generate an iridium metalacycle bound by the COD ligand of the [Ir(COD)Cl]2 precursor and one additional labile dative ligand. Such complexes catalyze the reactions of linear allylic esters with alkylamines, arylamines, phenols, alcohols, imides, carbamates, ammonia, enolates and enolate equivalents, as well as typical stabilized carbon nucleophiles generated from malonates and cyanoesters. Iridium catalysts for enantioselective allylic substitution have also been generated from phosphorus ligands with substituents bound by heteroatoms, and an account of the studies of such systems, along with a description of the development of iridium catalysts is included.

  9. Chromosome painting of Z and W sex chromosomes in Characidium (Characiformes, Crenuchidae).

    Science.gov (United States)

    Pazian, Marlon F; Shimabukuro-Dias, Cristiane Kioko; Pansonato-Alves, José Carlos; Oliveira, Claudio; Foresti, Fausto

    2013-03-01

    Some species of the genus Characidium have heteromorphic ZZ/ZW sex chromosomes with a totally heterochromatic W chromosome. Methods for chromosome microdissection associated with chromosome painting have become important tools for cytogenetic studies in Neotropical fish. In Characidium cf. fasciatum, the Z chromosome contains a pericentromeric heterochromatin block, whereas the W chromosome is completely heterochromatic. Therefore, a probe was produced from the W chromosome through microdissection and degenerate oligonucleotide-primed polymerase chain reaction amplification. FISH was performed using the W probe on the chromosomes of specimens of this species. This revealed expressive marks in the pericentromeric region of the Z chromosome as well as a completely painted W chromosome. When applying the same probe on chromosome preparations of C. cf. gomesi and Characidium sp., a pattern similar to C. cf. fasciatum was found, while C. cf. zebra, C. cf. lagosantense and Crenuchus spilurus species showed no hybridization signals. Structural changes in the chromosomes of an ancestral sexual system in the group that includes the species C. cf. gomesi, C. cf. fasciatum and Characidium sp., could have contributed to the process of speciation and could represent a causal mechanism of chromosomal diversification in this group. The heterochromatinization process possibly began in homomorphic and homologous chromosomes of an ancestral form, and this process could have given rise to the current patterns found in the species with sex chromosome heteromorphism.

  10. Entropy as the driver of chromosome segregation.

    Science.gov (United States)

    Jun, Suckjoon; Wright, Andrew

    2010-08-01

    We present a new physical biology approach to understanding the relationship between the organization and segregation of bacterial chromosomes. We posit that replicated Escherichia coli daughter strands will spontaneously demix as a result of entropic forces, despite their strong confinement within the cell; in other words, we propose that entropy can act as a primordial physical force which drives chromosome segregation under the right physical conditions. Furthermore, proteins implicated in the regulation of chromosome structure and segregation may in fact function primarily in supporting such an entropy-driven segregation mechanism by regulating the physical state of chromosomes. We conclude that bacterial chromosome segregation is best understood in terms of spontaneous demixing of daughter strands. Our concept may also have important implications for chromosome segregation in eukaryotes, in which spindle-dependent chromosome movement follows an extended period of sister chromatid demixing and compaction.

  11. Flow cytometric detection of aberrant chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Gray, J.W.; Lucas, J.; Yu, L.C.; Langlois, R.

    1983-05-11

    This report describes the quantification of chromosomal aberrations by flow cytometry. Both homogeneously and heterogeneously occurring chromosome aberrations were studied. Homogeneously occurring aberrations were noted in chromosomes isolated from human colon carcinoma (LoVo) cells, stained with Hoechst 33258 and chromomycin A3 and analyzed using dual beam flow cytometry. The resulting bivariate flow karyotype showed a homogeneously occurring marker chromosome of intermediate size. Heterogeneously occurring aberrations were quantified by slit-scan flow cytometry in chromosomes isolated from control and irradiated Chinese hamster cells and stained with propidium iodide. Heterogeneously occurring dicentric chromosomes were detected by their shapes (two centrometers). The frequencies of such chromosomes estimated by slit-scan flow cytometry correlated well with the frequencies determined by visual microscopy.

  12. Chromosome X aneuploidy in Brazilian schizophrenic patients.

    Science.gov (United States)

    de Moraes, Leopoldo Silva; Khayat, André Salim; de Lima, Patrícia Danielle Lima; Lima, Eleonidas Moura; Pinto, Giovanny Rebouças; Leal, Mariana Ferreira; de Arruda Cardoso Smith, Marília; Burbano, Rommel Rodríguez

    2010-01-01

    The identification of cytogenetic abnormalities in schizophrenic patients may provide clues to the genes involved in this disease. For this reason, a chromosomal analysis of samples from 62 schizophrenics and 70 controls was performed with trypsin-Giemsa banding and fluorescence in situ hybridization of the X chromosome. A clonal pericentric inversion on chromosome 9 was detected in one male patient, and we also discovered mosaicism associated with X chromosome aneuploidy in female patients, primarily detected in schizophrenic and normal female controls over 40 years old. When compared with age-matched female controls, the frequency of X chromosome loss was not significantly different between schizophrenics and controls, except for the 40- to 49-year-old age group. Our findings suggest that the X chromosome loss seen in schizophrenic patients is inherent to the normal cellular aging process. However, our data also suggest that X chromosome gain may be correlated with schizophrenia in this Brazilian population.

  13. Chromosomal instability determines taxane response

    DEFF Research Database (Denmark)

    Swanton, C.; Nicke, B.; Schuett, M.;

    2009-01-01

    -positive breast cancer and occurs frequently in basal-like and Her2-positive cases. In diploid cells, but not in chromosomally unstable cells, paclitaxel causes repression of CIN-survival genes, followed by cell death. In the OV01 ovarian cancer clinical trial, a high level of CIN was associated with taxane...... chromosomal instability (CIN). Silencing 22/50 of these genes, many of which are involved in DNA repair, caused cancer cell death, suggesting that these genes are involved in the survival of aneuploid cells. Overexpression of these "CIN-survival'' genes is associated with poor outcome in estrogen receptor...... resistance but carboplatin sensitivity, indicating that CIN may determine MTS response in vivo. Thus, pretherapeutic assessment of CIN may optimize treatment stratification and clinical trial design using these agents....

  14. Bacterial Chromosome Organization and Segregation

    OpenAIRE

    Toro, Esteban; Shapiro, Lucy

    2010-01-01

    Bacterial chromosomes are generally ∼1000 times longer than the cells in which they reside, and concurrent replication, segregation, and transcription/translation of this crowded mass of DNA poses a challenging organizational problem. Recent advances in cell-imaging technology with subdiffraction resolution have revealed that the bacterial nucleoid is reliably oriented and highly organized within the cell. Such organization is transmitted from one generation to the next by progressive segrega...

  15. Environmental pollution, chromosomes, and health

    Science.gov (United States)

    Bell, Peter M.

    In mid-May, 1980, President Carter declared a state of emergency at the Love Canal area, near Niagara Falls, New York. The reason for this was for the U.S. to underwrite the relocation costs ($3-5 million) of some 2500 residents who, according to a report by the EPA (Environmental Protection Agency) may have suffered damaged chromosomes. These injuries were apparently caused by contact with toxic wastes that had been dumped in the area in the years prior to development for housing.That the toxic compounds exist in the Love Canal and Niagara Falls subsurface zones, including public water supplies, appears to be established fact. That the residents of the Love Canal area suffered chromosomal damage may be established fact as well. Whether or not these two findings can be linked to ill health of the residents is another matter. Recently, the EPA report has been described as having ‘close to zero scientific significance,’ and has been ‘discredited’(Science, 208, 123a, 1980). The reasons for this disparity go beyond differences of opinion, beyond possible inadequacies of the EPA study, and even beyond problems that probably will arise from future studies, including those now in the planning stages. The problem is that even if victims have easily recognizable injuries from toxic substances (injury that apparently has not occurred to Love Canal residents), medical science usually cannot show a causal relationship. Even chromosomal damage is, at best, difficult to interpret. In ideal studies of significant populations and control groups, the association of toxic chemical to chromosome damage and to cancer and birth defects is indirect and, up to now, has been shown to have little or no significance to an individual member of the exposed population.

  16. Chromosomal Organization and Sequence Diversity of Genes Encoding Lachrymatory Factor Synthase in Allium cepa L.

    Science.gov (United States)

    Masamura, Noriya; McCallum, John; Khrustaleva, Ludmila; Kenel, Fernand; Pither-Joyce, Meegham; Shono, Jinji; Suzuki, Go; Mukai, Yasuhiko; Yamauchi, Naoki; Shigyo, Masayoshi

    2012-06-01

    Lachrymatory factor synthase (LFS) catalyzes the formation of lachrymatory factor, one of the most distinctive traits of bulb onion (Allium cepa L.). Therefore, we used LFS as a model for a functional gene in a huge genome, and we examined the chromosomal organization of LFS in A. cepa by multiple approaches. The first-level analysis completed the chromosomal assignment of LFS gene to chromosome 5 of A. cepa via the use of a complete set of A. fistulosum-shallot (A. cepa L. Aggregatum group) monosomic addition lines. Subsequent use of an F(2) mapping population from the interspecific cross A. cepa × A. roylei confirmed the assignment of an LFS locus to this chromosome. Sequence comparison of two BAC clones bearing LFS genes, LFS amplicons from diverse germplasm, and expressed sequences from a doubled haploid line revealed variation consistent with duplicated LFS genes. Furthermore, the BAC-FISH study using the two BAC clones as a probe showed that LFS genes are localized in the proximal region of the long arm of the chromosome. These results suggested that LFS in A. cepa is transcribed from at least two loci and that they are localized on chromosome 5.

  17. Dgcr8 and Dicer are essential for sex chromosome integrity during meiosis in males.

    Science.gov (United States)

    Modzelewski, Andrew J; Hilz, Stephanie; Crate, Elizabeth A; Schweidenback, Caterina T H; Fogarty, Elizabeth A; Grenier, Jennifer K; Freire, Raimundo; Cohen, Paula E; Grimson, Andrew

    2015-06-15

    Small RNAs play crucial roles in regulating gene expression during mammalian meiosis. To investigate the function of microRNAs (miRNAs) and small interfering RNAs (siRNAs) during meiosis in males, we generated germ-cell-specific conditional deletions of Dgcr8 and Dicer in mice. Analysis of spermatocytes from both conditional knockout lines revealed that there were frequent chromosomal fusions during meiosis, always involving one or both sex chromosomes. RNA sequencing indicates upregulation of Atm in spermatocytes from miRNA-deficient mice, and immunofluorescence imaging demonstrates an increased abundance of activated ATM kinase and mislocalization of phosphorylated MDC1, an ATM phosphorylation substrate. The Atm 3'UTR contains many potential microRNA target sites, and, notably, target sites for several miRNAs depleted in both conditional knockout mice were highly effective at promoting repression. RNF8, a telomere-associated protein whose localization is controlled by the MDC1-ATM kinase cascade, normally associates with the sex chromosomes during pachytene, but in both conditional knockouts redistributed to the autosomes. Taken together, these results suggest that Atm dysregulation in microRNA-deficient germ lines contributes to the redistribution of proteins involved in chromosomal stability from the sex chromosomes to the autosomes, resulting in sex chromosome fusions during meiotic prophase I.

  18. Down syndrome phenotypes: The consequences of chromosomal imbalance

    Energy Technology Data Exchange (ETDEWEB)

    Korenberg, J.R.; Chen, X.N.; Schipper, R.; Sun, Z.; Gonsky, R.; Gerwehr, S.; Graham, J.M. Jr. (Univ. of California, Los Angeles, CA (United States)); Carpenter, N.; Say, B. (H.A. Chapman Institute of Medical Genetics, Tulsa, OK (United States)); Daumer, C. (Univ. of Munich (Germany)) (and others)

    1994-05-24

    Down syndrome (DS) is a major cause of mental retardation and congenital heart disease. Besides a characteristic set of facial and physical features, DS is associated with congenital anomalies of the gastrointestinal tract, an increased risk of leukemia, immune system defects, and an Alzheimer-like dementia. Moreover, DS is a model for the study of human aneuploidy. Although usually caused by the presence of an extra chromosome 21, subsets of the phenotypic features of DS may be caused by the duplication of small regions of the chromosome. The physical map of chromosome 21 allows the molecular definition of the regions duplicated in these rare cases of partial trisomy. As a first step in identifying the genes responsible for individual DS features and their pathophysiology, a panel of cell lines derived from 16 such individuals has been established and the molecular break points have been determined using fluorescence in situ hybridization and Southern blot dosage analysis of 32 markers unique to human chromosome 21. Combining this information with detailed clinical evaluations of these patients, the authors have now constructed a [open quotes]phenotypic map[close quotes] that includes 25 features and assigns regions of 2-20 megabases as likely to contain the genes responsible. This study provides evidence for a significant contribution of genes outside the D21S55 region to the DS phenotypes, including the facies, microcephaly, short stature, hypotonia, abnormal dermatoglyphics, and mental retardation. This strongly suggests DS is a contiguous gene syndrome and augurs against a single DS chromosomal region responsible for most of the DS phenotypic features.

  19. Mechanisms of Chromosome Congression during Mitosis

    Science.gov (United States)

    Maiato, Helder; Gomes, Ana Margarida; Sousa, Filipe; Barisic, Marin

    2017-01-01

    Chromosome congression during prometaphase culminates with the establishment of a metaphase plate, a hallmark of mitosis in metazoans. Classical views resulting from more than 100 years of research on this topic have attempted to explain chromosome congression based on the balance between opposing pulling and/or pushing forces that reach an equilibrium near the spindle equator. However, in mammalian cells, chromosome bi-orientation and force balance at kinetochores are not required for chromosome congression, whereas the mechanisms of chromosome congression are not necessarily involved in the maintenance of chromosome alignment after congression. Thus, chromosome congression and maintenance of alignment are determined by different principles. Moreover, it is now clear that not all chromosomes use the same mechanism for congressing to the spindle equator. Those chromosomes that are favorably positioned between both poles when the nuclear envelope breaks down use the so-called “direct congression” pathway in which chromosomes align after bi-orientation and the establishment of end-on kinetochore-microtubule attachments. This favors the balanced action of kinetochore pulling forces and polar ejection forces along chromosome arms that drive chromosome oscillatory movements during and after congression. The other pathway, which we call “peripheral congression”, is independent of end-on kinetochore microtubule-attachments and relies on the dominant and coordinated action of the kinetochore motors Dynein and Centromere Protein E (CENP-E) that mediate the lateral transport of peripheral chromosomes along microtubules, first towards the poles and subsequently towards the equator. How the opposite polarities of kinetochore motors are regulated in space and time to drive congression of peripheral chromosomes only now starts to be understood. This appears to be regulated by position-dependent phosphorylation of both Dynein and CENP-E and by spindle microtubule

  20. Mechanisms of Chromosome Congression during Mitosis

    Directory of Open Access Journals (Sweden)

    Helder Maiato

    2017-02-01

    Full Text Available Chromosome congression during prometaphase culminates with the establishment of a metaphase plate, a hallmark of mitosis in metazoans. Classical views resulting from more than 100 years of research on this topic have attempted to explain chromosome congression based on the balance between opposing pulling and/or pushing forces that reach an equilibrium near the spindle equator. However, in mammalian cells, chromosome bi-orientation and force balance at kinetochores are not required for chromosome congression, whereas the mechanisms of chromosome congression are not necessarily involved in the maintenance of chromosome alignment after congression. Thus, chromosome congression and maintenance of alignment are determined by different principles. Moreover, it is now clear that not all chromosomes use the same mechanism for congressing to the spindle equator. Those chromosomes that are favorably positioned between both poles when the nuclear envelope breaks down use the so-called “direct congression” pathway in which chromosomes align after bi-orientation and the establishment of end-on kinetochore-microtubule attachments. This favors the balanced action of kinetochore pulling forces and polar ejection forces along chromosome arms that drive chromosome oscillatory movements during and after congression. The other pathway, which we call “peripheral congression”, is independent of end-on kinetochore microtubule-attachments and relies on the dominant and coordinated action of the kinetochore motors Dynein and Centromere Protein E (CENP-E that mediate the lateral transport of peripheral chromosomes along microtubules, first towards the poles and subsequently towards the equator. How the opposite polarities of kinetochore motors are regulated in space and time to drive congression of peripheral chromosomes only now starts to be understood. This appears to be regulated by position-dependent phosphorylation of both Dynein and CENP-E and by spindle

  1. Chromosome aberration assays in Allium

    Energy Technology Data Exchange (ETDEWEB)

    Grant, W.F.

    1982-01-01

    The common onion (Allium cepa) is an excellent plant for the assay of chromosome aberrations after chemical treatment. Other species of Allium (A. cepa var. proliferum, A. carinatum, A. fistulosum and A. sativum) have also been used but to a much lesser extent. Protocols have been given for using root tips from either bulbs or seeds of Allium cepa to study the cytological end-points, such as chromosome breaks and exchanges, which follow the testing of chemicals in somatic cells. It is considered that both mitotic and meiotic end-points should be used to a greater extent in assaying the cytogenetic effects of a chemical. From a literature survey, 148 chemicals are tabulated that have been assayed in 164 Allium tests for their clastogenic effect. Of the 164 assays which have been carried out, 75 are reported as giving a positive reaction, 49 positive and with a dose response, 1 positive and temperature-related, 9 borderline positive, and 30 negative; 76% of the chemicals gave a definite positive response. It is proposed that the Allium test be included among those tests routinely used for assessing chromosomal damage induced by chemicals.

  2. A Newborn with Genital Ambiguity, 45,X/46,XY Mosaicism, a Jumping Chromosome Y, and Congenital Adrenal Hyperplasia.

    Science.gov (United States)

    Zhang, Lei; Cooley, Linda D; Chandratre, Sonal R; Ahmed, Atif; Jacobson, Jill D

    2013-01-01

    Disorders of sex development (DSD), formerly termed "intersex" conditions, arise from numerous causes. CAH secondary to 21-hydroxylase deficiency is the most common cause of DSD. Sex chromosome disorders, including sex chromosome mosaicism, are the second most common cause of DSD. We discuss a medically complex neonate with DSD presenting with ambiguous genitalia. Hormone levels suggested 21-hydroxylase deficiency. Molecular analysis revealed compound heterozygous mutations in the 21-hydroxylase gene (CYP21A2), confirming the diagnosis of CAH. Chromosome analysis revealed sex chromosome mosaicism with three cell lines: 45,X[8]/45,X,tas(Y;16)(p11.32;p13.3)[8]/45,X,t(Y;8)(p11.32;p23.3)[4] with the Y chromosome in telomere association with chromosomes 8p and 16p in different cell lines, a "jumping translocation." Histologically, the right gonad had irregular, distended seminiferous tubules with hyperplastic germ cells contiguous with ovarian stroma and primordial follicles. The left gonad had scant ovarian stroma and embryonic remnants. Chromosome analyses showed mosaicism in both gonads: 45,X[17]/45,X,tas(Y;8)(p11.32;p23.3)[3]. This is the first case of coexisting CAH and 45,X/46,XY mosaicism reported in the English literature and the third case of a constitutional chromosome Y "jumping translocation." Our report documents the medical and genetic complexity of children such as this one with ambiguous genitalia and discusses the need for a multidisciplinary team approach.

  3. Progression of colorectal cancer is associated with multiple tumor suppressor gene defects but inhibition of tumorigenicity is accomplished by correction of any single defect via chromosome transfer

    Energy Technology Data Exchange (ETDEWEB)

    Goyette, M.C.; Fasching, C.L.; Stanbridge, E.J. (Univ. of California, Irvine (United States)); Cho, K.; Levy, D.B.; Kinzler, K.W.; Vogelstein, B. (John Hopkins Univ. School of Medicine and Hospital, Baltimore, MD (United States)); Paraskeva, C. (Univ. of Bristol, University Walk, Bristol (United Kingdom))

    1992-03-01

    Colorectal cancer has been associated with the activation of ras oncogenes and with the deletion of multiple chromosomal regions including chromosomes 5q, 17p, and 18q. The candidate tumor suppressor genes from these regions are, respectively, MCC and/or APC, p53, and DCC. In order to further understanding of the molecular and genetic mechanisms involved in tumor progression and, thereby, of normal cell growth, it is important to determine whether defects in one or more of these loci contribute functionally in the progression to malignancy in colorectal cancer and whether correction of any of these defects restores normal growth control in vitro and in vivo. To address this question, the authors have utilized the technique of microcell-mediated chromosome transfer to introduce normal human chromosomes 5, 17, and 18 individually into recipient colorectal cancer cells. Additionally, chromosome 15 was introduced into SW480 cells as an irrelevant control chromosome. While the introduction of chromosome 17 into the tumorigenic colorectal cell line SW480 yielded no viable clones, cell lines were established after the introduction of chromosomes 15, 5, and 18. SW480-chromosome 5 hybrids are strongly suppressed for tumorigenicity, while SW480-chromosome 18 hybrids produce slowly growing tumors in some of the animals injected. Hybrids containing the introduced chromosome 5 express the APC gene present on that chromosome as well as the endogenous mutant transcript. Expression of the putative tumor suppressor gene, DCC, was seen in the clones containing the introduced chromosome 18 but was significantly reduced in several of the tumor reconstitute cell lines. Our findings indicate that while multiple defects in tumor suppressor genes seem to be required for progression to the malignant state in colorectal cancer, correction of only a single defect can have significant effects in vivo and/or in vitro.

  4. [Molecular cytogenetic methods for studying interphase chromosomes in human brain cells].

    Science.gov (United States)

    Iurov, I Iu; Vorsanova, S G; Solov'ev, I V; Iurov, Iu B

    2010-09-01

    One of the main genetic factors determining the functional activity of the genome in somatic cells, including brain nerve cells, is the spatial organization of chromosomes in the interphase nucleus. For a long time, no studies of human brain cells were carried out until high-resolution methods of molecular cytogenetics were developed to analyze interphase chromosomes in nondividing somatic cells. The purpose of the present work was to assess the potential of high-resolution methods of interphase molecular cytogenetics for studying chromosomes and the nuclear organization in postmitotic brain cells. A high efficiency was shown by such methods as multiprobe and quantitative fluorescence in situ hybridization (Multiprobe FISH and QFISH), ImmunoMFISH (analysis of the chromosome organization in different types of brain cells), and interphase chromosome-specific multicolor banding (ICS-MCB). These approaches allowed studying the nuclear organization depending on the gene composition and types of repetitive DNA of specific chromosome regions in certain types of brain cells (in neurons and glial cells, in particular). The present work demonstrates a high potential of interphase molecular cytogenetics for studying the structural and functional organizations of the cell nucleus in highly differentiated nerve cells. Analysis of interphase chromosomes of brain cells in the normal and pathological states can be considered as a promising line of research in modern molecular cytogenetics and cell neurobiology, i. e., molecular neurocytogenetics.

  5. Chromosomal manipulation by site-specific recombinases and fluorescent protein-based vectors.

    Directory of Open Access Journals (Sweden)

    Munehiro Uemura

    Full Text Available Feasibility of chromosomal manipulation in mammalian cells was first reported 15 years ago. Although this technique is useful for precise understanding of gene regulation in the chromosomal context, a limited number of laboratories have used it in actual practice because of associated technical difficulties. To overcome the practical hurdles, we developed a Cre-mediated chromosomal recombination system using fluorescent proteins and various site-specific recombinases. These techniques enabled quick construction of targeting vectors, easy identification of chromosome-rearranged cells, and rearrangement leaving minimum artificial elements at junctions. Applying this system to a human cell line, we successfully recapitulated two types of pathogenic chromosomal translocations in human diseases: MYC/IgH and BCR/ABL1. By inducing recombination between two loxP sites targeted into the same chromosome, we could mark cells harboring deletion or duplication of the inter-loxP segments with different colors of fluorescence. In addition, we demonstrated that the intrachromosomal recombination frequency is inversely proportional to the distance between two recombination sites, implicating a future application of this frequency as a proximity sensor. Our method of chromosomal manipulation can be employed for particular cell types in which gene targeting is possible (e.g. embryonic stem cells. Experimental use of this system would open up new horizons in genome biology, including the establishment of cellular and animal models of diseases caused by translocations and copy-number variations.

  6. The contribution of the Y chromosome to hybrid male sterility in house mice.

    Science.gov (United States)

    Campbell, Polly; Good, Jeffrey M; Dean, Matthew D; Tucker, Priscilla K; Nachman, Michael W

    2012-08-01

    Hybrid sterility in the heterogametic sex is a common feature of speciation in animals. In house mice, the contribution of the Mus musculus musculus X chromosome to hybrid male sterility is large. It is not known, however, whether F1 male sterility is caused by X-Y or X-autosome incompatibilities or a combination of both. We investigated the contribution of the M. musculus domesticus Y chromosome to hybrid male sterility in a cross between wild-derived strains in which males with a M. m. musculus X chromosome and M. m. domesticus Y chromosome are partially sterile, while males from the reciprocal cross are reproductively normal. We used eight X introgression lines to combine different X chromosome genotypes with different Y chromosomes on an F1 autosomal background, and we measured a suite of male reproductive traits. Reproductive deficits were observed in most F1 males, regardless of Y chromosome genotype. Nonetheless, we found evidence for a negative interaction between the M. m. domesticus Y and an interval on the M. m. musculus X that resulted in abnormal sperm morphology. Therefore, although F1 male sterility appears to be caused mainly by X-autosome incompatibilities, X-Y incompatibilities contribute to some aspects of sterility.

  7. Detection of low level sex chromosome mosaicism in Ullrich-Turner syndrome patients.

    Science.gov (United States)

    Wiktor, Anne E; Van Dyke, Daniel L

    2005-10-15

    Ullrich-Turner syndrome (UTS) is most commonly due to a 45,X chromosome defect, but is also seen in patients with a variety of X-chromosome abnormalities or 45,X/46,XY mosaicism. The phenotype of UTS patients is highly variable, and depends largely on the karyotype. Patients are at an increased risk of gonadoblastoma when a Y-derived chromosome or chromosome fragment is present. Since constitutional mosaicism is present in approximately 50% of UTS patients, the identification of minor cell populations is clinically important and a challenge to laboratories. We identified 50 females with a 45,X karyotype as the sole abnormality or as part of a more complex karyotype. Twenty two (44%) had a 45,X karyotype; mosaicism for a second normal or structurally abnormal X was observed in 24 (48%) samples, and mosaicism for Y chromosomal material in 4 (8%) cases. To further investigate the possibility of mosaicism in the 22 patients with an apparently non-mosaic 45,X karyotype, we performed FISH using centromere probes for the X and Y chromosomes. A minor XX cell line was identified in 3 patients, and the 45,X result was confirmed in 19 samples. No samples with XY mosaicism were identified. We describe our validation process for a FISH assay to be used in clinical practice to identify XX or XY mosaicism. FISH as an adjunct to karyotype analysis provides a sensitive and cost-effective technique to identify sex chromosome mosaicism in UTS patients.

  8. Nanodissection of human chromosomes with near-infrared femtosecond laser pulses.

    Science.gov (United States)

    König, K; Riemann, I; Fritzsche, W

    2001-06-01

    Near-infrared laser pulses of a compact 80-MHz femtosecond laser source at 800 nm, a mean power of 15-100 mW, 170-fs pulse width, and millisecond beam dwell times at the target have been used for multiphoton-mediated nanoprocessing of human chromosomes. By focusing of the laser beam with high-numerical-aperture objectives of a scanning microscope to diffraction-limited spots and with light intensities of terawatts per cubic centimeter, precise submicrometer holes and cuts in human chromosomes have been processed by single-point exposure and line scans. A minimum FWHM cut size of ~100 nm during a partial dissection of chromosome 1, which is below the diffraction-limited spot size, and a minimum material removal of ~0.003mum (3) were determined by a scanning-force microscope. The plasma-induced ablated material corresponds to ~1/400 of the chromosome 1 volume and to ~65x10(3) base pairs of chromosomal DNA. A complete dissection could be performed with FWHM cut sizes below 200 nm. High-repetition-frequency femtosecond lasers at low mean power in combination with high-numerical-aperture focusing optics appear therefore as appropriate noncontact tools for nanoprocessing of bulk and (or) surfaces of transparent materials such as chromosomes. In particular, the noninvasive inactivation of certain genomic regions on single chromosomes within living cells becomes possible.

  9. Comparative Genomics of Interreplichore Translocations in Bacteria: A Measure of Chromosome Topology?

    Science.gov (United States)

    Khedkar, Supriya; Seshasayee, Aswin Sai Narain

    2016-06-01

    Genomes evolve not only in base sequence but also in terms of their architecture, defined by gene organization and chromosome topology. Whereas genome sequence data inform us about the changes in base sequences for a large variety of organisms, the study of chromosome topology is restricted to a few model organisms studied using microscopy and chromosome conformation capture techniques. Here, we exploit whole genome sequence data to study the link between gene organization and chromosome topology in bacteria. Using comparative genomics across ∼250 pairs of closely related bacteria we show that: (a) many organisms show a high degree of interreplichore translocations throughout the chromosome and not limited to the inversion-prone terminus (ter) or the origin of replication (oriC); (b) translocation maps may reflect chromosome topologies; and (c) symmetric interreplichore translocations do not disrupt the distance of a gene from oriC or affect gene expression states or strand biases in gene densities. In summary, we suggest that translocation maps might be a first line in defining a gross chromosome topology given a pair of closely related genome sequences.

  10. Genetic rearrangements of six wheat-agropyron cristatum 6P addition lines revealed by molecular markers.

    Directory of Open Access Journals (Sweden)

    Haiming Han

    Full Text Available Agropyron cristatum (L. Gaertn. (2n = 4x = 28, PPPP not only is cultivated as pasture fodder but also could provide many desirable genes for wheat improvement. It is critical to obtain common wheat-A. cristatum alien disomic addition lines to locate the desired genes on the P genome chromosomes. Comparative analysis of the homoeologous relationships between the P genome chromosome and wheat genome chromosomes is a key step in transferring different desirable genes into common wheat and producing the desired alien translocation line while compensating for the loss of wheat chromatin. In this study, six common wheat-A. cristatum disomic addition lines were produced and analyzed by phenotypic examination, genomic in situ hybridization (GISH, SSR markers from the ABD genomes and STS markers from the P genome. Comparative maps, six in total, were generated and demonstrated that all six addition lines belonged to homoeologous group 6. However, chromosome 6P had undergone obvious rearrangements in different addition lines compared with the wheat chromosome, indicating that to obtain a genetic compensating alien translocation line, one should recombine alien chromosomal regions with homoeologous wheat chromosomes. Indeed, these addition lines were classified into four types based on the comparative mapping: 6PI, 6PII, 6PIII, and 6PIV. The different types of chromosome 6P possessed different desirable genes. For example, the 6PI type, containing three addition lines, carried genes conferring high numbers of kernels per spike and resistance to powdery mildew, important traits for wheat improvement. These results may prove valuable for promoting the development of conventional chromosome engineering techniques toward molecular chromosome engineering.

  11. Ring Chromosome 9 and Chromosome 9p Deletion Syndrome in a Patient Associated with Developmental Delay: A Case Report and Review of the Literature.

    Science.gov (United States)

    Sivasankaran, Aswini; Kanakavalli, Murthy K; Anuradha, Deenadayalu; Samuel, Chandra R; Kandukuri, Lakshmi R

    2016-01-01

    Ring chromosomes have been described for all human chromosomes and are typically associated with physical and/or mental abnormalities resulting from a deletion of the terminal ends of both chromosome arms. This report describes the presence of a ring chromosome 9 in a 2-year-old male child associated with developmental delay. The proband manifested a severe phenotype comprising facial dysmorphism, congenital heart defects, and seizures. The child also exhibited multiple cell lines with mosaic patterns of double rings, a dicentric ring and loss of the ring associated with mitotic instability and dynamic tissue-specific mosaicism. His karyotype was 46,XY,r(9)(p22q34)[89]/46,XY,dic r(9; 9)(p22q34;p22q34)[6]/45, XY,-9[4]/47,XY,r(9),+r(9)[1]. However, the karyotypes of his parents and elder brother were normal. FISH using mBAND probe and subtelomeric probes specific for p and q arms for chromosome 9 showed no deletion in any of the regions. Chromosomal microarray analysis led to the identification of a heterozygous deletion of 15.7 Mb from 9p22.3 to 9p24.3. The probable role of the deleted genes in the manifestation of the phenotype of the proband is discussed.

  12. Chromosomal divergence and evolutionary inferences in Rhodniini based on the chromosomal location of ribosomal genes

    Directory of Open Access Journals (Sweden)

    Sebastian Pita

    2013-05-01

    Full Text Available In this study, we used fluorescence in situ hybridisation to determine the chromosomal location of 45S rDNA clusters in 10 species of the tribe Rhodniini (Hemiptera: Reduviidae: Triatominae. The results showed striking inter and intraspecific variability, with the location of the rDNA clusters restricted to sex chromosomes with two patterns: either on one (X chromosome or both sex chromosomes (X and Y chromosomes. This variation occurs within a genus that has an unchanging diploid chromosome number (2n = 22, including 20 autosomes and 2 sex chromosomes and a similar chromosome size and genomic DNA content, reflecting a genome dynamic not revealed by these chromosome traits. The rDNA variation in closely related species and the intraspecific polymorphism in Rhodnius ecuadoriensis suggested that the chromosomal position of rDNA clusters might be a useful marker to identify recently diverged species or populations. We discuss the ancestral position of ribosomal genes in the tribe Rhodniini and the possible mechanisms involved in the variation of the rDNA clusters, including the loss of rDNA loci on the Y chromosome, transposition and ectopic pairing. The last two processes involve chromosomal exchanges between both sex chromosomes, in contrast to the widely accepted idea that the achiasmatic sex chromosomes of Heteroptera do not interchange sequences.

  13. Whole chromosome painting of B chromosomes of the red-eye tetra Moenkhausia sanctaefilomenae (Teleostei, Characidae).

    Science.gov (United States)

    Scudeler, Patricia Elda Sobrinho; Diniz, Débora; Wasko, Adriane Pinto; Oliveira, Claudio; Foresti, Fausto

    2015-01-01

    B chromosomes are dispensable genomic elements found in different groups of animals and plants. In the present study, a whole chromosome probe was generated from a specific heterochromatic B chromosome occurring in cells of the characidae fish Moenkhausia sanctaefilomenae (Steindachner, 1907). The chromosome painting probes were used in fluorescence in situ hybridization (FISH) experiments for the assessment of metaphase chromosomes obtained from individuals from three populations of Moenkhausia sanctaefilomenae. The results revealed that DNA sequences were shared between a specific B chromosome and many chromosomes of the A complement in all populations analyzed, suggesting a possible intra-specific origin of these B chromosomes. However, no hybridization signals were observed in other B chromosomes found in the same individuals, implying a possible independent origin of B chromosome variants in this species. FISH experiments using 18S rDNA probes revealed the presence of non-active ribosomal genes in some B chromosomes and in some chromosomes of the A complement, suggesting that at least two types of B chromosomes had an independent origin. The role of heterochromatic segments and ribosomal sequences in the origin of B chromosomes were discussed.

  14. Phenotyping mouse chromosome substitution strains reveal multiple QTLs for febrile seizure susceptibility

    NARCIS (Netherlands)

    Hessel, E V S; van Gassen, K L I; Wolterink-Donselaar, I G; Stienen, P J; Fernandes, C; Brakkee, J H; Kas, M J H; de Graan, P N E

    2009-01-01

    Febrile seizures (FS) are the most common seizure type in children and recurrent FS are a risk factor for developing temporal lobe epilepsy. Although the mechanisms underlying FS are largely unknown, recent family, twin and animal studies indicate that genetics are important in FS susceptibility. He

  15. Phenotyping mouse chromosome substitution strains reveal multiple QTLs for febrile seizure susceptibility.

    NARCIS (Netherlands)

    Hessel, E.V.; Gassen, K.L.I. van; Wolterink-Donselaar, I.G.; Stienen, P.J.; Fernandes, C.; Brakkee, J.H.; Kas, M.J.; Graan, P.N. de

    2009-01-01

    Febrile seizures (FS) are the most common seizure type in children and recurrent FS are a risk factor for developing temporal lobe epilepsy. Although the mechanisms underlying FS are largely unknown, recent family, twin and animal studies indicate that genetics are important in FS susceptibility. He

  16. FISH studies of chromosome abnormalities in germ cells and its relevance in reproductive counseling

    Institute of Scientific and Technical Information of China (English)

    Zaida Sarrate; Joan Blanco; Ester Anton; Susana Egozcue; Josep Egozcue; Francesca Vidal

    2005-01-01

    Chromosome abnormalities are one of the major causes of human infertility. In infertile males, abnormal karyotypes are more frequent than in the general population. Furthermore, meiotic disorders affecting the germ cell-line have been observed in men with normal somatic karyotypes consulting for infertility. In both cases, the production of unbalanced spermatozoa has been demonstrated. Basically addressed to establish reproductive risks, fluorescence in situ hybridization (FISH) on decondensed sperm heads has become the most frequently used method to evaluate the chromosomal constitution of spermatozoa in carriers of numerical sex chromosome abnormalities, carriers of structural chromosome reorganizations and infertile males with normal karyotype. The aim of this review is to present updated figures of the information obtained through sperm FISH studies with an emphasis on its clinical significance. Furthermore, the incorporation of novel FISH-based techniques (Multiplex-FISH; Multi-FISH) in male infertility studies is also discussed.

  17. Transmission rate variation among three B chromosome variants in the fish Prochilodus lineatus (Characiformes, Prochilodontidae

    Directory of Open Access Journals (Sweden)

    MANOLO PENITENTE

    2013-09-01

    Full Text Available Cytogenetic studies were developed in Prochilodus lineatus (Valenciennes 1836, describing an interesting system of small supernumerary chromosomes. The purpose of this work is to study the frequency and morphology of B chromosomes in individuals from the parental line and the inheritance patterns of these elements in individuals obtained from controlled crosses in the species P. lineatus. The transmission rate of B chromosomes revealed a kB=0.388 for the acrocentric type, a kB=0.507 for the metacentric type and a kB=0.526 for the submetacentric type. The obtained results raise hypothesis that B-acrocentric chromosomes are involved in an extinction process in this species, while the metacentric and submetacentric supernumerary elements comprises a neutral mechanism and follows a Mendelian transmission rate.

  18. Refining the genetic portrait of Portuguese Roma through X-chromosomal markers

    DEFF Research Database (Denmark)

    Pereira, Vania; Gusmão, Leonor; Valente, Cristina

    2012-01-01

    of Portuguese Roma (Gypsies) by analyzing 43 X-chromosomal markers and 53 autosomal markers. Portuguese individuals of non-Gypsy ancestry were also studied. Compared with the host population, reduced levels of diversity on the X chromosome and autosomes were detected in Gypsies; this result was in line...... with known patterns of genetic diversity typical of Roma groups. As a consequence of the complex demographic past of the Roma, during which admixture and genetic drift played major roles, the amount of linkage disequilibrium (LD) on the X chromosome in Gypsies was considerably higher than that observed...... in non-Gypsies. When the pattern of differentiation on the X chromosome was compared with that of autosomes, there was evidence for asymmetries in female and male effective population sizes during the admixture between Roma and non-Roma. This result supplements previous data provided by mtDNA and the Y...

  19. Cytogenetic and molecular markers for detecting Aegilops uniaristata chromosomes in a wheat background.

    Science.gov (United States)

    Gong, Wenping; Li, Guangrong; Zhou, Jianping; Li, Genying; Liu, Cheng; Huang, Chengyan; Zhao, Zhendong; Yang, Zujun

    2014-09-01

    Aegilops uniaristata has many agronomically useful traits that can be used for wheat breeding. So far, a Triticum turgidum - Ae. uniaristata amphiploid and one set of Chinese Spring (CS) - Ae. uniaristata addition lines have been produced. To guide Ae. uniaristata chromatin transformation from these lines into cultivated wheat through chromosome engineering, reliable cytogenetic and molecular markers specific for Ae. uniaristata chromosomes need to be developed. Standard C-banding shows that C-bands mainly exist in the centromeric regions of Ae. uniaristata but rarely at the distal ends. Fluorescence in situ hybridization (FISH) using (GAA)8 as a probe showed that the hybridization signal of chromosomes 1N-7N are different, thus (GAA)8 can be used to identify all Ae. uniaristata chromosomes in wheat background simultaneously. Moreover, a total of 42 molecular markers specific for Ae. uniaristata chromosomes were developed by screening expressed sequence tag - sequence tagged site (EST-STS), expressed sequence tag - simple sequence repeat (EST-SSR), and PCR-based landmark unique gene (PLUG) primers. The markers were subsequently localized using the CS - Ae. uniaristata addition lines and different wheat cultivars as controls. The cytogenetic and molecular markers developed herein will be helpful for screening and identifying wheat - Ae. uniaristata progeny.

  20. Development of a two-parameter slit-scan flow cytometer for screening of normal and aberrant chromosomes: application to a karyotype of Sus scrofa domestica (pig)

    Science.gov (United States)

    Hausmann, Michael; Doelle, Juergen; Arnold, Armin; Stepanow, Boris; Wickert, Burkhard; Boscher, Jeannine; Popescu, Paul C.; Cremer, Christoph

    1992-07-01

    Laser fluorescence activated slit-scan flow cytometry offers an approach to a fast, quantitative characterization of chromosomes due to morphological features. It can be applied for screening of chromosomal abnormalities. We give a preliminary report on the development of the Heidelberg slit-scan flow cytometer. Time-resolved measurement of the fluorescence intensity along the chromosome axis can be registered simultaneously for two parameters when the chromosome axis can be registered simultaneously for two parameters when the chromosome passes perpendicularly through a narrowly focused laser beam combined by a detection slit in the image plane. So far automated data analysis has been performed off-line on a PC. In its final performance, the Heidelberg slit-scan flow cytometer will achieve on-line data analysis that allows an electro-acoustical sorting of chromosomes of interest. Interest is high in the agriculture field to study chromosome aberrations that influence the size of litters in pig (Sus scrofa domestica) breeding. Slit-scan measurements have been performed to characterize chromosomes of pigs; we present results for chromosome 1 and a translocation chromosome 6/15.

  1. Chromosome aberrations induced by zebularine in triticale.

    Science.gov (United States)

    Ma, Xuhui; Wang, Qing; Wang, Yanzhi; Ma, Jieyun; Wu, Nan; Ni, Shuang; Luo, Tengxiao; Zhuang, Lifang; Chu, Chenggen; Cho, Seong-Woo; Tsujimoto, Hisashi; Qi, Zengjun

    2016-07-01

    Chromosome engineering is an important approach for generating wheat germplasm. Efficient development of chromosome aberrations will facilitate the introgression and application of alien genes in wheat. In this study, zebularine, a DNA methylation transferase inhibitor, was successfully used to induce chromosome aberrations in the octoploid triticale cultivar Jinghui#1. Dry seeds were soaked in zebularine solutions (250, 500, and 750 μmol/L) for 24 h, and the 500 μmol/L treatment was tested in three additional treatment times, i.e., 12, 36, and 48 h. All treatments induced aberrations involving wheat and rye chromosomes. Of the 920 cells observed in 67 M1 plants, 340 (37.0%) carried 817 aberrations with an average of 0.89 aberrations per cell (range: 0-12). The aberrations included probable deletions, telosomes and acentric fragments (49.0%), large segmental translocations (28.9%), small segmental translocations (17.1%), intercalary translocations (2.6%), long chromosomes that could carry more than one centromere (2.0%), and ring chromosomes (0.5%). Of 510 M2 plants analyzed, 110 (21.6%) were found to carry stable aberrations. Such aberrations included 79 with varied rye chromosome numbers, 7 with wheat and rye chromosome translocations, 15 with possible rye telosomes/deletions, and 9 with complex aberrations involving variation in rye chromosome number and wheat-rye translocations. These indicated that aberrations induced by zebularine can be steadily transmitted, suggesting that zebularine is a new efficient agent for chromosome manipulation.

  2. The importance of having two X chromosomes.

    Science.gov (United States)

    Arnold, Arthur P; Reue, Karen; Eghbali, Mansoureh; Vilain, Eric; Chen, Xuqi; Ghahramani, Negar; Itoh, Yuichiro; Li, Jingyuan; Link, Jenny C; Ngun, Tuck; Williams-Burris, Shayna M

    2016-02-19

    Historically, it was thought that the number of X chromosomes plays little role in causing sex differences in traits. Recently, selected mouse models have been used increasingly to compare mice with the same type of gonad but with one versus two copies of the X chromosome. Study of these models demonstrates that mice with one X chromosome can be strikingly different from those with two X chromosomes, when the differences are not attributable to confounding group differences in gonadal hormones. The number of X chromosomes affects adiposity and metabolic disease, cardiovascular ischaemia/reperfusion injury and behaviour. The effects of X chromosome number are likely the result of inherent differences in expression of X genes that escape inactivation, and are therefore expressed from both X chromosomes in XX mice, resulting in a higher level of expression when two X chromosomes are present. The effects of X chromosome number contribute to sex differences in disease phenotypes, and may explain some features of X chromosome aneuploidies such as in Turner and Klinefelter syndromes.

  3. Chromosome analysis of arsenic affected cattle

    Directory of Open Access Journals (Sweden)

    S. Shekhar

    2014-10-01

    Full Text Available Aim: The aim was to study the chromosome analysis of arsenic affected cattle. Materials and Methods: 27 female cattle (21 arsenic affected and 6 normal were selected for cytogenetical study. The blood samples were collected, incubated, and cultured using appropriate media and specific methods. The samples were analyzed for chromosome number and morphology, relative length of the chromosome, arm ratio, and centromere index of X chromosome and chromosomal abnormalities in arsenic affected cattle to that of normal ones. Results: The diploid number of metaphase chromosomes in arsenic affected cattle as well as in normal cattle were all 2n=60, 58 being autosomes and 2 being sex chromosomes. From the centromeric position, karyotyping studies revealed that all the 29 pair of autosomes was found to be acrocentric or telocentric, and the sex chromosomes (XX were submetacentric in both normal and arsenic affected cattle. The relative length of all the autosome pairs and sex chrosomosome pair was found to be higher in normal than that of arsenic affected cattle. The mean arm ratio of X-chromosome was higher in normal than that of arsenic affected cattle, but it is reverse in case of centromere index value of X-chromosome. There was no significant difference of arm ratio and centromere index of X-chromosomes between arsenic affected and normal cattle. No chromosomal abnormalities were found in arsenic affected cattle. Conclusion: The chromosome analysis of arsenic affected cattle in West Bengal reported for the first time in this present study which may serve as a guideline for future studies in other species. These reference values will also help in comparison of cytological studies of arsenic affected cattle to that of various toxicants.

  4. The probability to initiate X chromosome inactivation is determined by the X to autosomal ratio and X chromosome specific allelic properties.

    Directory of Open Access Journals (Sweden)

    Kim Monkhorst

    Full Text Available In female mammalian cells, random X chromosome inactivation (XCI equalizes the dosage of X-encoded gene products to that in male cells. XCI is a stochastic process, in which each X chromosome has a probability to be inactivated. To obtain more insight in the factors setting up this probability, we studied the role of the X to autosome (X ratio A ratio in initiation of XCI, and have used the experimental data in a computer simulation model to study the cellular population dynamics of XCI.To obtain more insight in the role of the XratioA ratio in initiation of XCI, we generated triploid mouse ES cells by fusion of haploid round spermatids with diploid female and male ES cells. These fusion experiments resulted in only XXY triploid ES cells. XYY and XXX ES lines were absent, suggesting cell death related either to insufficient X-chromosomal gene dosage (XYY or to inheritance of an epigenetically modified X chromosome (XXX. Analysis of active (Xa and inactive (Xi X chromosomes in the obtained triploid XXY lines indicated that the initiation frequency of XCI is low, resulting in a mixed population of XaXiY and XaXaY cells, in which the XaXiY cells have a small proliferative advantage. This result, and findings on XCI in diploid and tetraploid ES cell lines with different X ratio A ratios, provides evidence that the X ratio A ratio determines the probability for a given X chromosome to be inactivated. Furthermore, we found that the kinetics of the XCI process can be simulated using a probability for an X chromosome to be inactivated that is proportional to the X ratio A ratio. These simulation studies re-emphasize our hypothesis that the probability is a function of the concentration of an X-encoded activator of XCI, and of X chromosome specific allelic properties determining the threshold for this activator.The present findings reveal that the probability for an X chromosome to be inactivated is proportional to the X ratio A ratio. This finding

  5. Evaluation of radiosensitivity of human tumor cells after irradiation of γ-rays based on G2-chromosome aberrations

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The aim of the present investigation is to determine initial G2-chromosome aberrations and to validate whether the G2-chromosome aberrations can predict the cellular clonogenic survival in human tumor cell lines. Cell lines of human ovary carcinoma cells (HO8910) and human hepatoma cells (HepG2) were irradiated with a range of doses and assessed both for initial G2-chromosome aberrations and for cell survival after γ-irradiation. The initial G2-chromosome aberrations were measured by counting the number of G2-chromatid breaks after irradiation, detected by the premature chromosome condensation technique, and the G2-assay method. Cell survival was documented by a colony formation assay. A linear-quadratic survival curve was observed in both cell lines. The dose-response results show that the numbers of G2-chromatid breaks increase with the increase in dose in the two cell lines. At higher doses (higher than 4 Gy) of irradiation, the number of G2-chromatid breaks for the G2-assay method cannot be determined because too few cells reach mitosis, and hence their detection is difficult. A good correlation is found between the clonogenic survival and the radiation-induced initial G2-chromatid breaks per cell (r=0.9616). The present results suggest that the premature chromosome condensation technique may be useful for determining chromatid breaks in G2 cells, and the number of initial G2-chromatid breaks holds promise for predicting the radiosensitivity of tumor cells.

  6. Assignment of the human gene for the water channel of renal collecting duct Aquaporin 2 (AQP2) to chromosome 12 region q12-->q13

    NARCIS (Netherlands)

    Deen, P M; Weghuis, D O; Sinke, R J; Geurts van Kessel, A; Wieringa, B; van Os, C H

    1994-01-01

    The chromosomal localization of the gene encoding Aquaporin 2 (previously called WCH-CD), which acts as a water channel in the collecting tubules of the kidney, was determined. Southern blot hybridizations of chromosomal DNA from a panel of 25 different human-rodent hybrid cell lines assigned AQP2 t

  7. Deciphering evolutionary strata on plant sex chromosomes and fungal mating-type chromosomes through compositional segmentation.

    Science.gov (United States)

    Pandey, Ravi S; Azad, Rajeev K

    2016-03-01

    Sex chromosomes have evolved from a pair of homologous autosomes which differentiated into sex determination systems, such as XY or ZW system, as a consequence of successive recombination suppression between the gametologous chromosomes. Identifying the regions of recombination suppression, namely, the "evolutionary strata", is central to understanding the history and dynamics of sex chromosome evolution. Evolution of sex chromosomes as a consequence of serial recombination suppressions is well-studied for mammals and birds, but not for plants, although 48 dioecious plants have already been reported. Only two plants Silene latifolia and papaya have been studied until now for the presence of evolutionary strata on their X chromosomes, made possible by the sequencing of sex-linked genes on both the X and Y chromosomes, which is a requirement of all current methods that determine stratum structure based on the comparison of gametologous sex chromosomes. To circumvent this limitation and detect strata even if only the sequence of sex chromosome in the homogametic sex (i.e. X or Z chromosome) is available, we have developed an integrated segmentation and clustering method. In application to gene sequences on the papaya X chromosome and protein-coding sequences on the S. latifolia X chromosome, our method could decipher all known evolutionary strata, as reported by previous studies. Our method, after validating on known strata on the papaya and S. latifolia X chromosome, was applied to the chromosome 19 of Populus trichocarpa, an incipient sex chromosome, deciphering two, yet unknown, evolutionary strata. In addition, we applied this approach to the recently sequenced sex chromosome V of the brown alga Ectocarpus sp. that has a haploid sex determination system (UV system) recovering the sex determining and pseudoautosomal regions, and then to the mating-type chromosomes of an anther-smut fungus Microbotryum lychnidis-dioicae predicting five strata in the non

  8. Biologic and synthetic skin substitutes: An overview

    Directory of Open Access Journals (Sweden)

    Halim Ahmad

    2010-10-01

    Full Text Available The current trend of burn wound care has shifted to more holistic approach of improvement in the long-term form and function of the healed burn wounds and quality of life. This has demanded the emergence of various skin substitutes in the management of acute burn injury as well as post burn reconstructions. Skin substitutes have important roles in the treatment of deep dermal and full thickness wounds of various aetiologies. At present, there is no ideal substitute in the market. Skin substitutes can be divided into two main classes, namely, biological and synthetic substitutes. The biological skin substitutes have a more intact extracellular matrix structure, while the synthetic skin substitutes can be synthesised on demand and can be modulated for specific purposes. Each class has its advantages and disadvantages. The biological skin substitutes may allow the construction of a more natural new dermis and allow excellent re-epithelialisation characteristics due to the presence of a basement membrane. Synthetic skin substitutes demonstrate the advantages of increase control over scaffold composition. The ultimate goal is to achieve an ideal skin substitute that provides an effective and scar-free wound healing.

  9. Scaling Chromosomes for an Evolutionary Karyotype: A Chromosomal Tradeoff between Size and Number across Woody Species.

    Science.gov (United States)

    Liang, Guolu; Chen, Hong

    2015-01-01

    This study aims to examine the expected scaling relationships between chromosome size and number across woody species and to clarify the importance of the scaling for the maintenance of chromosome diversity by analyzing the scaling at the inter- & intra-chromosomal level. To achieve for the goals, chromosome trait data were extracted for 191 woody species (including 56 evergreen species and 135 deciduous species) from the available literature. Cross-species analyses revealed a tradeoff among chromosomes between chromosome size and number, demonstrating there is selective mechanism crossing chromosomes among woody species. And the explanations for the result were presented from intra- to inter-chromosome contexts that the scaling may be compromises among scale symmetry, mechanical requirements, and resource allocation across chromosomes. Therein, a 3/4 scaling pattern was observed between total chromosomes and m-chromosomes within nucleus which may imply total chromosomes may evolve from more to less. In addition, the primary evolutionary trend of karyotype and the role of m-chromosomes in the process of karyotype evolution were also discussed.

  10. Microdissection and chromosome painting of X and B chromosomes in Locusta migratoria.

    Science.gov (United States)

    Teruel, María; Cabrero, Josefa; Montiel, Eugenia E; Acosta, Manuel J; Sánchez, Antonio; Camacho, Juan Pedro M

    2009-01-01

    Acquisition of knowledge of the nature and DNA content of B chromosomes has been triggered by a collection of molecular techniques, one of which, microdissection, has provided interesting results in a number of B chromosome systems. Here we provide the first data on the molecular composition of B chromosomes in Locusta migratoria, after microdissection of the B and X chromosomes, DNA amplification by one (B) or two (X) different methods, and chromosome painting. The results showed that B chromosomes share at least two types of repetitive DNA sequences with the A chromosomes, suggesting that Bs in this species most likely arose intraspecifically. One of these repetitive DNAs is located on the heterochromatic distal half of the B chromosome and in the pericentromeric regions of about half of the A chromosomes, including the X. The other type of repetitive DNA is located interspersedly over the non-centromeric euchromatic regions of all A chromosomes and in an interstitial part of the proximal euchromatic half of the B chromosome. Chromosome painting, however, did not provide results sufficiently reliable to determine, in this species, which A chromosome gave rise to the B; this might be done by detailed analysis of the microdissected DNA sequences.

  11. International workshop on chromosome 3. Final report, April 15, 1991--April 14, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Gemmill, R.M.

    1992-07-01

    The Second Workshop on Human Chromosome 3 was held on April 4--5, 1991 at Denver, Colorado. There were 43 participants representing 8 nations. The workshop participants reviewed the current state of the chromosome 3 map, both physical and genetic, and prepared lists of markers and cell lines to be made commonly available. These markers and cell lines should be incorporated into the mapping efforts of diverse groups to permit the integration of data and development of consensus maps at future workshops. Region specific efforts were described for sections of the chromosome harboring genes thought to be involved in certain diseases including Von Hippel-Lindau disease, 3p-syndrome, lung cancer and renal cancer. Selected papers have been processed separately for inclusion in the Energy Science and Technology Database.

  12. Cement from magnesium substituted hydroxyapatite.

    Science.gov (United States)

    Lilley, K J; Gbureck, U; Knowles, J C; Farrar, D F; Barralet, J E

    2005-05-01

    Brushite cement may be used as a bone graft material and is more soluble than apatite in physiological conditions. Consequently it is considerably more resorbable in vivo than apatite forming cements. Brushite cement formation has previously been reported by our group following the mixture of nanocrystalline hydroxyapatite and phosphoric acid. In this study, brushite cement was formed from the reaction of nanocrystalline magnesium-substituted hydroxyapatite with phosphoric acid in an attempt to produce a magnesium substituted brushite cement. The presence of magnesium was shown to have a strong effect on cement composition and strength. Additionally the presence of magnesium in brushite cement was found to reduce the extent of brushite hydrolysis resulting in the formation of HA. By incorporating magnesium ions in the apatite reactant structure the concentration of magnesium ions in the liquid phase of the cement was controlled by the dissolution rate of the apatite. This approach may be used to supply other ions to cement systems during setting as a means to manipulate the clinical performance and characteristics of brushite cements.

  13. Building bridges within the bacterial chromosome.

    Science.gov (United States)

    Song, Dan; Loparo, Joseph J

    2015-03-01

    All organisms must dramatically compact their genomes to accommodate DNA within the cell. Bacteria use a set of DNA-binding proteins with low sequence specificity called nucleoid-associated proteins (NAPs) to assist in chromosome condensation and organization. By bending or bridging DNA, NAPs also facilitate chromosome segregation and regulate gene expression. Over the past decade, emerging single-molecule and chromosome conformation capture techniques have investigated the molecular mechanisms by which NAPs remodel and organize the bacterial chromosome. In this review we describe how such approaches reveal the biochemical mechanisms of three NAPs that are believed to facilitate DNA bridging: histone-like nucleoid structuring protein (H-NS), ParB, and structural maintenance of chromosomes (SMC). These three proteins form qualitatively different DNA bridges, leading to varied effects on transcription and chromosome segregation.

  14. Sexual maldevelopment and sex reversal, chromosomal causes.

    Science.gov (United States)

    Magenis, R Ellen

    2006-01-01

    The SRY gene on the Y chromosome is the testis determining factor (TDF). It is therefore the initial male determining factor. However, phenotypic sex determination includes a cascade of genes located on autosomes as well as sex chromosomes. Aberrations of these genes may cause sexual maldevelopment or sex reversal. Abnormalities may include single gene mutations and gene loss or gain-changes may involve only sex organs or may be part of syndromes. These changes may also arise as chromosome abnormalities involving contiguous genes. Eight cases with chromosomal abnormalities involving different causative mechanisms are described herein. The most common cause is nondisjunction, including loss or gain of sex chromosomes. Less common causes are mispairing and crossing over in meiosis, chromosome breaks with repair, nonhomologous pairing due to low copy repeats and crossing over, and translocation (familial or de novo) with segregation. Cases include: [see: text].

  15. Germplasm Enhancement of Maize: A look into haploid induction and chromosomal doubling of haploids from temperate-adapted tropical sources

    Science.gov (United States)

    Doubled haploid technology is used to develop completely homozygous inbred lines, where each of the chromatids making up a chromosome pair are identical. Two inbred lines, PHB47 and PHZ51, were used to make backcrosses to 18 maize landraces, generating 36 populations. The landraces were chosen bas...

  16. Chromosomal rearrangements in Tourette syndrome

    DEFF Research Database (Denmark)

    Bertelsen, Birgitte; Debes, Nanette Mol; Hjermind, Lena E

    2013-01-01

    Tourette syndrome (TS) is a childhood-onset complex neurobiological disorder characterized by a combination of persistent motor and vocal tics and frequent presence of other neuropsychiatric comorbidities. TS shares the fate of other complex disorders, where the genetic etiology is largely unknown......, and identification of susceptibility genes through linkage and association studies has been complicated due to inherent difficulties such as no clear mode of inheritance, genetic heterogeneity, and apparently incomplete penetrance. Positional cloning through mapping of disease-related chromosome rearrangements has...

  17. Meiosis I: When Chromosomes Undergo Extreme Makeover

    OpenAIRE

    Miller, Matthew P; Amon, Angelika; Ünal, Elçin

    2013-01-01

    The ultimate success of cell division relies on the accurate partitioning of the genetic material. Errors in this process occur in nearly all tumors and are the leading cause of miscarriages and congenital birth defects in humans. Two cell divisions, mitosis and meiosis, use common as well as unique mechanisms to ensure faithful chromosome segregation. In mitosis, alternating rounds of DNA replication and chromosome segregation preserves the chromosome complement of the progenitor cell. In co...

  18. High Line

    DEFF Research Database (Denmark)

    Kiib, Hans

    2015-01-01

    At just over 10 meters above street level, the High Line extends three kilometers through three districts of Southwestern Manhattan in New York. It consists of simple steel construction, and previously served as an elevated rail line connection between Penn Station on 34th Street and the many....... The High Line project has been carried out as part of an open conversion strategy. The result is a remarkable urban architectural project, which works as a catalyst for the urban development of Western Manhattan. The greater project includes the restoration and reuse of many old industrial buildings...... in close proximity to the park bridge and new projects being added to fit the context. The outcome is a conglomeration of non-contemporary urban activities along the High Line, where mechanical workshops, small wholesale stores. etc. mix with new exclusive residential buildings, eminent cafés...

  19. High Line

    DEFF Research Database (Denmark)

    Kiib, Hans

    2015-01-01

    in close proximity to the park bridge and new projects being added to fit the context. The outcome is a conglomeration of non-contemporary urban activities along the High Line, where mechanical workshops, small wholesale stores. etc. mix with new exclusive residential buildings, eminent cafés......At just over 10 meters above street level, the High Line extends three kilometers through three districts of Southwestern Manhattan in New York. It consists of simple steel construction, and previously served as an elevated rail line connection between Penn Station on 34th Street and the many...... factories and warehouses on Gansevoort Street. Today the High Line is a beautiful park covered with new tiles, viewing platforms and smaller recreational areas. The park bridge has simple, uniform, urban fittings and features a variety of flowering plants, grasses, shrubs and trees from around the world...

  20. Movement of chromosomes with severed kinetochore microtubules.

    Science.gov (United States)

    Forer, Arthur; Johansen, Kristen M; Johansen, Jørgen

    2015-05-01

    Experiments dating from 1966 and thereafter showed that anaphase chromosomes continued to move poleward after their kinetochore microtubules were severed by ultraviolet microbeam irradiation. These observations were initially met with scepticism as they contradicted the prevailing view that kinetochore fibre microtubules pulled chromosomes to the pole. However, recent experiments using visible light laser microbeam irradiations have corroborated these earlier experiments as anaphase chromosomes again were shown to move poleward after their kinetochore microtubules were severed. Thus, multiple independent studies using different techniques have shown that chromosomes can indeed move poleward without direct microtubule connections to the pole, with only a kinetochore 'stub' of microtubules. An issue not yet settled is: what propels the disconnected chromosome? There are two not necessarily mutually exclusive proposals in the literature: (1) chromosome movement is propelled by the kinetochore stub interacting with non-kinetochore microtubules and (2) chromosome movement is propelled by a spindle matrix acting on the stub. In this review, we summarise the data indicating that chromosomes can move with severed kinetochore microtubules and we discuss proposed mechanisms for chromosome movement with severed kinetochore microtubules.

  1. Genome architecture: domain organization of interphase chromosomes.

    Science.gov (United States)

    Bickmore, Wendy A; van Steensel, Bas

    2013-03-14

    The architecture of interphase chromosomes is important for the regulation of gene expression and genome maintenance. Chromosomes are linearly segmented into hundreds of domains with different protein compositions. Furthermore, the spatial organization of chromosomes is nonrandom and is characterized by many local and long-range contacts among genes and other sequence elements. A variety of genome-wide mapping techniques have made it possible to chart these properties at high resolution. Combined with microscopy and computational modeling, the results begin to yield a more coherent picture that integrates linear and three-dimensional (3D) views of chromosome organization in relation to gene regulation and other nuclear functions.

  2. Cognitive and medical features of chromosomal aneuploidy.

    Science.gov (United States)

    Hutaff-Lee, Christa; Cordeiro, Lisa; Tartaglia, Nicole

    2013-01-01

    This chapter describes the physical characteristics, medical complications, and cognitive and psychological profiles that are associated with chromosomal aneuploidy conditions, a group of conditions in which individuals are born with one or more additional chromosome. Overall, chromosomal aneuploidy conditions occur in approximately 1 in 250 children. Information regarding autosomal disorders including trisomy 21 (Down syndrome), trisomy 13 (Patau syndrome), and trisomy 18 (Edward syndrome) are presented. Sex chromosome aneuploidy conditions such as Klinefelter syndrome (47,XXY), XYY, trisomy X, and Turner syndrome (45,X), in addition to less frequently occurring tetrasomy and pentasomy conditions are also covered. Treatment recommendations and suggestions for future research directions are discussed.

  3. Research on automatic human chromosome image analysis

    Science.gov (United States)

    Ming, Delie; Tian, Jinwen; Liu, Jian

    2007-11-01

    Human chromosome karyotyping is one of the essential tasks in cytogenetics, especially in genetic syndrome diagnoses. In this thesis, an automatic procedure is introduced for human chromosome image analysis. According to different status of touching and overlapping chromosomes, several segmentation methods are proposed to achieve the best results. Medial axis is extracted by the middle point algorithm. Chromosome band is enhanced by the algorithm based on multiscale B-spline wavelets, extracted by average gray profile, gradient profile and shape profile, and calculated by the WDD (Weighted Density Distribution) descriptors. The multilayer classifier is used in classification. Experiment results demonstrate that the algorithms perform well.

  4. Meiotic chromosome abnormalities in human spermatogenesis.

    Science.gov (United States)

    Martin, Renée H

    2006-08-01

    The last few years have witnessed an explosion in the information about chromosome abnormalities in human sperm and the meiotic events that predispose to these abnormalities. We have determined that all chromosomes are susceptible to nondisjunction, but chromosomes 21 and 22 and, especially, the sex chromosomes have an increased frequency of aneuploidy. Studies are just beginning on the effects of potential mutagens on the chromosomal constitution of human sperm. The effects of pesticides and cancer therapeutic agents have been reviewed. In the last decade, there has been a great impetus to study chromosome abnormalities in sperm from infertile men because the advent of intracytoplasmic sperm injection (ICSI) made it possible for these men to father pregnancies. A large number of studies have demonstrated that infertile men have an increased frequency of chromosomally abnormal sperm and children, even when they have a normal somatic karyotype. Meiotic studies on the pachytene stage of spermatogenesis have demonstrated that infertile men have impaired chromosome synapsis, a significantly decreased frequency of recombination, and an increased frequency of chromosomes completely lacking a recombination site. Such errors make these cells susceptible to meiotic arrest and the production of aneuploid gametes.

  5. Formation of substituted oxa- and azarhodacyclobutanes.

    Science.gov (United States)

    Dauth, Alexander; Rigling, Carla; Tsoung, Jennifer; Love, Jennifer A

    2013-12-01

    The preparation of substituted oxa- and azarhodacyclobutanes is reported. After exchange of ethylene with a variety of unsymmetrically and symmetrically substituted alkenes, the corresponding rhodium-olefin complexes were oxidized with H2O2 and PhINTs (Ts=p-toluenesulfonyl) to yield the substituted oxa- and azarhodacyclobutanes, respectively. Oxarhodacyclobutanes could be prepared with excellent selectivity for incorporation of the oxygen atom on the more substituted carbon atom of the alkene. At the same time, azarhodacyclobutanes showed good-to-excellent selectivity for heteroatom incorporation on the less substituted carbon. Furthermore, it was shown that steric modifications of the ancillary ligand have a significant influence on the selectivity of Rh-olefin complex formation as well as formation of the substituted azametallacycles.

  6. Trends in Substitution Models of Molecular Evolution

    Directory of Open Access Journals (Sweden)

    Miguel eArenas

    2015-10-01

    Full Text Available Substitution models of evolution describe the process of genetic variation through fixed mutations and constitute the basis of the evolutionary analysis at the molecular level. Almost forty years after the development of first substitution models, highly sophisticated and data-specific substitution models continue emerging with the aim of better mimicking real evolutionary processes. Here I describe current trends in substitution models of DNA, codon and amino acid sequence evolution, including advantages and pitfalls of the most popular models. The perspective concludes that despite the large number of currently available substitution models, further research is required for more realistic modeling, especially for DNA coding and amino acid data. Additionally, the development of more accurate complex models should be coupled with new implementations and improvements of methods and frameworks for substitution model selection and downstream evolutionary analysis.

  7. Allelic gains and losses in distinct regions of chromosome 6 in gastric carcinoma

    NARCIS (Netherlands)

    Carvalho, B; van der Veen, AY; Gartner, F; Carneiro, F; Seruca, R; Buys, CHCM; Kok, K

    2001-01-01

    In gastric cancer, alterations in the long arm of chromosome 6 are a frequent event. Two regions of heterozygous loss have been described: 6q16.3 similar to 6q23 and 6q26 similar to 6q27. We have evaluated by microsatellite and FISH analyses the 6q status of three cell lines that we established from

  8. Localization of introduced genes on the chromosomes of transgenic barley, wheat and triticale by fluorescence in situ hybridization

    DEFF Research Database (Denmark)

    Pedersen, C.; Zimny, J.; Becker, D.

    1997-01-01

    transformant showed a totally different integration pattern. Southern analysis confirmed that the inserted genes were segregating independently, resulting in different integration patterns among the progeny lines. The application of the FISH technique for the analysis of transgenic plants is discussed.......Using fluorescence in situ hybridization (FISH) we localized introduced genes on metaphase chromosomes of barley, wheat, and triticale transformed by microprojectile bombardment of microspores and scutellar tissue with the pDB1 plasmid containing the uidA and bar genes. Thirteen integration sites...... of single-copy integrations. There was a slight tendency towards the localization of transgenes in distal chromosome regions. Using the GAA-satellite sequence for chromosome banding, the chromosomes containing the inserted genes were identified in most cases. Two barley lines derived from the same...

  9. Currency substitution, portfolio diversification, and money demand

    OpenAIRE

    Freitas, Miguel Lebre de; Veiga, Francisco José

    2006-01-01

    We extend the Thomas (1985) dynamic optimising model of money demand and currency substitution to the case in which the individual has restricted or no access to foreign currency denominated bonds. In this case Currency Substitution decisions and Asset Substitution decisions are not separable. The results obtained suggest that the significance of an expected exchange rate depreciation term in the demand for domestic money provides a valid test for the presence of currency subst...

  10. Chromosomal rearrangements and the pathogenesis of differentiated thyroid cancer

    Directory of Open Access Journals (Sweden)

    Stefan K.G. Grebe

    2011-12-01

    Full Text Available The majority of thyroid cancers arise from the follicular cells of the thyroid gland, which yield a wide variety of distinct morphotypes, ranging from relatively indolent lesions to the most malignant forms of cancer known. The remaining primary thyroid cancers arise from C cells within the gland and result primarily from mutations of the RET protooncogene, germ line mutations of which give rise to the various forms of multiple endocrine neoplasia. The most common of the follicular cell-derived cancers are papillary carcinomas, (PTC, followed by follicular carcinomas (FTC and its Hurthle cell variant (HCC and finally anaplastic carcinomas (ATC. The pathogenesis of many thyroid cancers, of both PTC and FTC morphotype, involves chromosomal translocations. Rearrangements of the RET protoconcogene are known to be involved in the pathogenesis of ca. 50% of PTC. A similar proportion of FTC have been associated with a t(2;3(q13;p25 translocation, fusing the thyroid-specific transcription factor PAX8 with the peroxisome proliferator-activated receptor gamma (PPARγ nuclear receptor, a ubiquitously expressed transcription factor. These rearrangements have analogy with translocations in erythropoetic cells, which form the only other known group of human malignancies that are largely the result of chromosomal translocation events. In this review we compare and contrast the oncogenic properties of thyroid and erythroid chromosomal transformations and speculate on mechanisms leading to their formation.

  11. Structure, tissue distribution, and chromosomal localization of the prepronociceptin gene.

    Science.gov (United States)

    Mollereau, C; Simons, M J; Soularue, P; Liners, F; Vassart, G; Meunier, J C; Parmentier, M

    1996-08-01

    Nociceptin (orphanin FQ), the newly discovered natural agonist of opioid receptor-like (ORL1) receptor, is a neuropeptide that is endowed with pronociceptive activity in vivo. Nociceptin is derived from a larger precursor, prepronociceptin (PPNOC), whose human, mouse, and rat genes we have now isolated. The PPNOC gene is highly conserved in the three species and displays organizational features that are strikingly similar to those of the genes of preproenkephalin, preprodynorphin, and preproopiomelanocortin, the precursors to endogenous opioid peptides, suggesting the four genes belong to the same family-i.e., have a common evolutionary origin. The PPNOC gene encodes a single copy of nociceptin as well as of other peptides whose sequence is strictly conserved across murine and human species; hence it is likely to be neurophysiologically significant. Northern blot analysis shows that the PPNOC gene is predominantly transcribed in the central nervous system (brain and spinal cord) and, albeit weakly, in the ovary, the sole peripheral organ expressing the gene. By using a radiation hybrid cell line panel, the PPNOC gene was mapped to the short arm of human chromosome 8 (8p21), between sequence-tagged site markers WI-5833 and WI-1172, in close proximity of the locus encoding the neurofilament light chain NEFL. Analysis of yeast artificial chromosome clones belonging to the WC8.4 contig covering the 8p21 region did not allow to detect the presence of the gene on these yeast artificial chromosomes, suggesting a gap in the coverage within this contig.

  12. Increased chromosome radiosensitivity during pregnancy

    Energy Technology Data Exchange (ETDEWEB)

    Ricoul, Michelle; Sabatier, Laure; Dutrillaux, Bernard [Commissariat a l`Energie Atomique, Laboratoire de Radiobiologie et Oncologie, DRR, DSV, Fontenay aux roses (France)

    1997-03-04

    It was necessary to consider the risks of exposure of pregnant women, not only in relation to the child, but also in relation to their own hypersensitivity. We have demonstrated that pregnancy increases radiosensitivity of chromosome in the mouse at the end of gestation. This is of importance since it may have implications on radioprotection of pregnant women and give experimental guidelines to the problems of hypersensitivity to drugs and cancer aggravation during pregnancy. Blood obtained from women at various times of pregnancy was exposed to ionizing radiations. By comparison to non-pregnant women, an increase in chromosome breakage was observed in metaphases from lymphocytes, after short-term culture in the presence of the serum of the same donor. Immediately after delivery, this increase in radiosensitivity disappeared. In a prospective study, serial analyses showed a very strong correlation between the amount of pregnancy hormones, progesterone in particular, and the increase in radiosensitivity. Pregnant women may have an increased sensitivity to ionizing radiation during the second half of their pregnancy. This study provides the first evidence in human that radiosensitivity may vary in relation to physiological conditions.

  13. The Philadelphia chromosome in leukemogenesis

    Institute of Scientific and Technical Information of China (English)

    ZhiJieKang; JinSongYan; QuentinLiu; YuFeiLiu; LingZhiXu; ZiJieLong; DanHuang; YaYang; BingLiu; JiuXingFeng; YuJiaPan

    2016-01-01

    The truncated chromosome 22 that results from the reciprocal translocation t(9;22)(q34;q11) is known as the Phila‑delphia chromosome (Ph) and is a hallmark of chronic myeloid leukemia (CML). In leukemia cells, Ph not only impairs the physiological signaling pathways but also disrupts genomic stability. This aberrant fusion gene encodes the breakpoint cluster region‑proto‑oncogene tyrosine‑protein kinase (BCR‑ABL1) oncogenic protein with persistently enhanced tyrosine kinase activity. The kinase activity is responsible for maintaining proliferation, inhibiting differentia‑tion, and conferring resistance to cell death. During the progression of CML from the chronic phase to the accelerated phase and then to the blast phase, the expression patterns of different BCR‑ABL1 transcripts vary. Each BCR‑ABL1 transcript is present in a distinct leukemia phenotype, which predicts both response to therapy and clinical outcome. Besides CML, the Ph is found in acute lymphoblastic leukemia, acute myeloid leukemia, and mixed‑phenotype acute leukemia. Here, we provide an overview of the clinical presentation and cellular biology of different phenotypes of Ph‑positive leukemia and highlight key ifndings regarding leukemogenesis.

  14. Chromosomal replicons of higher plants

    Energy Technology Data Exchange (ETDEWEB)

    Van' t Hof, J.

    1987-03-16

    This brief discussion of replicons of higher plants offers a glimpse into the properties of chromosomal DNA replication. It gives evidence that the S phase of unrelated plant species is comprised of temporally ordered replicon families that increase in number with genome size. This orderly process, which assures a normal inheritance of genetic material to recipient daughter cells, is maintained at the level of replicon clusters by two mutually exclusive mechanisms, one involving the rate at which single replicons replicate their allotment of DNA, and another by means of the tempo-pause. The same two mechanisms are used by cells to alter the pattern of chromosomal DNA replication just prior to and during normal development. Both mechanisms are genetically determined and produce genetic effects when disturbed of disrupted by additional non-conforming DNAs. Further insight into how these two mechanisms operate requires more molecular information about the nature of replicons and the factors that govern when a replicon family replicates. Plant material is a rich and ideal source for this information just awaiting exploitation. 63 refs.

  15. Chromosomal phenotypes and submicroscopic abnormalities

    Directory of Open Access Journals (Sweden)

    Devriendt Koen

    2004-01-01

    Full Text Available Abstract The finding, during the last decade, that several common, clinically delineated syndromes are caused by submicroscopic deletions or, more rarely, by duplications, has provided a powerful tool in the annotation of the human genome. Since most microdeletion/microduplication syndromes are defined by a common deleted/duplicated region, abnormal dosage of genes located within these regions can explain the phenotypic similarities among individuals with a specific syndrome. As such, they provide a unique resource towards the genetic dissection of complex phenotypes such as congenital heart defects, mental and growth retardation and abnormal behaviour. In addition, the study of phenotypic differences in individuals with the same microdeletion syndrome may also become a treasury for the identification of modifying factors for complex phenotypes. The molecular analysis of these chromosomal anomalies has led to a growing understanding of their mechanisms of origin. Novel tools to uncover additional submicroscopic chromosomal anomalies at a higher resolution and higher speed, as well as the novel tools at hand for deciphering the modifying factors and epistatic interactors, are 'on the doorstep' and will, besides their obvious diagnostic role, play a pivotal role in the genetic dissection of complex phenotypes.

  16. Conservation of chromosomes syntenic with avian autosomes in squamate reptiles revealed by comparative chromosome painting.

    Science.gov (United States)

    Pokorná, Martina; Giovannotti, Massimo; Kratochvíl, Lukáš; Caputo, Vincenzo; Olmo, Ettore; Ferguson-Smith, Malcolm A; Rens, Willem

    2012-08-01

    In contrast to mammals, birds exhibit a slow rate of chromosomal evolution. It is not clear whether high chromosome conservation is an evolutionary novelty of birds or was inherited from an earlier avian ancestor. The evolutionary conservatism of macrochromosomes between birds and turtles supports the latter possibility; however, the rate of chromosomal evolution is largely unknown in other sauropsids. In squamates, we previously reported strong conservatism of the chromosomes syntenic with the avian Z, which could reflect a peculiarity of this part of the genome. The chromosome 1 of iguanians and snakes is largely syntenic with chromosomes 3, 5 and 7 of the avian ancestral karyotype. In this project, we used comparative chromosome painting to determine how widely this synteny is conserved across nine families covering most of the main lineages of Squamata. The results suggest that the association of the avian ancestral chromosomes 3, 5 and 7 can be dated back to at least the early Jurassic and could be an ancestral characteristic for Unidentata (Serpentes, Iguania, Anguimorpha, Laterata and Scinciformata). In Squamata chromosome conservatism therefore also holds for the parts of the genome which are homologous to bird autosomes, and following on from this, a slow rate of chromosomal evolution could be a common characteristic of all sauropsids. The large evolutionary stasis in chromosome organization in birds therefore seems to be inherited from their ancestors, and it is particularly striking in comparison with mammals, probably the only major tetrapod lineage with an increased rate of chromosomal rearrangements as a whole.

  17. Dehalogenation of aromatics by nucleophilic aromatic substitution.

    Science.gov (United States)

    Sadowsky, Daniel; McNeill, Kristopher; Cramer, Christopher J

    2014-09-16

    Nucleophilic aromatic substitution has been implicated as a mechanism for both the biotic and abiotic hydrodehalogenation of aromatics. Two mechanisms for the aqueous dehalogenation of aromatics involving nucleophilic aromatic substitution with hydride as a nucleophile are investigated using a validated density functional and continuum solvation protocol. For chlorinated and brominated aromatics, nucleophilic addition ortho to carbon-halogen bonds via an anionic intermediate is predicted to be the preferred mechanism in the majority of cases, while concerted substitution is predicted to be preferred for most fluorinated aromatics. Nucleophilic aromatic substitution reactions with the hydroxide and hydrosulfide anions as nucleophiles are also investigated and compared.

  18. Monodromy Substitutions and Rational Blowdowns

    CERN Document Server

    Endo, Hisaaki; van Horn-Morris, Jeremy

    2010-01-01

    We introduce several new families of relations in the mapping class groups of planar surfaces, each equating two products of right-handed Dehn twists. The interest of these relations lies in their geometric interpretation in terms of rational blowdowns of 4-manifolds, specifically via monodromy substitution in Lefschetz fibrations. The simplest example is the lantern relation, already shown by the first author and Gurtas to correspond to rational blowdown along a -4 sphere; here we give relations that extend that result to realize the "generalized" rational blowdowns of Fintushel-Stern and Park by monodromy subsitution, as well as several of the families of rational blowdowns discovered by Stipsicz-Szab\\'o-Wahl.

  19. Controversial issues of maternity substitution

    Directory of Open Access Journals (Sweden)

    Andy Pușcă

    2009-06-01

    Full Text Available Substitute maternity consists in a woman carrying a pregnancy (the implant of an embryo, at therequest of a sterile couple, most of the times in exchange of a sum of money, with her commitment tounconditionally give away the newborn after birth to the couple she concluded the agreement with. Manycontroversies emerged in what concerns the contract between the sterile couple and the carrying mother,especially when this contract is by onerous title, which happens in most of the cases. In that a civil contract? Is ita sales contract for the child? Is it a contract to provide services? Is it body marketing? Between total prohibitionand excessive liberalism, the middle way, which is the regulation according to ethical religious, cultural andsocial norms of each community, represents a realistic solution.

  20. Development of Oryza rufipogon and O. sativa Introgression Lines and Assessment for Yield-related Quantitative Trait Loci

    Institute of Scientific and Technical Information of China (English)

    Lubin Tan; Fengxia Liu; Wei Xue; Guijuan Wang; Sheng Ye; Zuofeng Zhu; Yongcai Fu; Xiangkun Wang; Chuanqing Sun

    2007-01-01

    Introgression lines population was effectively used in mapping quantitative trait loci (QTLs), identifying favorable genes, discovering hidden genetic variation, evaluating the action or interaction of QTLs in multiple conditions and providing the favorable experimental materials for plant breeding and genetic research. In this study, an advanced backcross and consecutive selfing strategy was used to develop introgression lines (ILs), which derived from an accession of Oryza rufipogon Griff, collected from Yuanjiang County, Yunnan Province of China, as the donor, and an elite indica cultivar Teqing (O. sativa L.), as the recipient. Introgression segments from O. rufipogon were screened using 179 polymorphic simple sequence repeats (SSR) markers in the genome of each IL. Introgressed segments carried by the introgression lines population contained 120 ILs covering the whole O. rufipogon genome. The mean number of homozygous O. rufipogon segments per introgression line was about 3.88. The average length of introgressed segments was approximate 25.5 cM, and about 20.8% of these segments had sizes less than 10 cM. The genome of each IL harbored the chromosomal fragments of O. rufipogon ranging from 0.54% to 23.7%, with an overall average of 5.79%. At each locus, the ratio of substitution of O. rufipogon alleles had a range of 1.67-9.33, with an average of 5.50. A wide range of alterations in morphological and yield-related traits were also found in the introgression lines population. Using single-point analysis, a total of 37 putative QTLs for yield and yield components were detected at two sites with 7%-20% explaining the phenotypic variance. Nineteen QTLs (51.4%) were detected at both sites, and the alleles from O. rufipogon at fifteen loci (40.5%) improved the yield and yield components in the Teqing background. These O. rufipogon-O. sativa introgression lines will serve as genetic materials for identifying and using favorable genes from common wild rice.

  1. Mapping of Ppd-B1, a Major Candidate Gene for Late Heading on Wild Emmer Chromosome Arm 2BS and Assessment of Its Interactions with Early Heading QTLs on 3AL.

    Directory of Open Access Journals (Sweden)

    Wei Zhou

    Full Text Available Wheat heading date is an important agronomic trait determining maturation time and yield. A set of common wheat (Triticum aestivum var. Chinese Spring; CS-wild emmer (T. turgidum L. subsp. dicoccoides (TDIC chromosome arm substitution lines (CASLs was used to identify and allocate QTLs conferring late or early spike emergence by examining heading date. Genetic loci accelerating heading were found on TDIC chromosome arms 3AL and 7BS, while loci delaying heading were located on 4AL and 2BS. To map QTLs conferring late heading on 2BS, F2 populations derived from two cross combinations of CASL2BS × CS and CASL3AL × CASL2BS were developed and each planted at two times, constituting four F2 mapping populations. Heading date varied continuously among individuals of these four populations, suggesting quantitative characteristics. A genetic map of 2BS, consisting of 23 SSR and one single-stranded conformation polymorphism (SSCP marker(s, was constructed using these F2 populations. This map spanned a genetic length of 53.2 cM with average marker density of 2.3 cM. The photoperiod-sensitivity gene Ppd-B1 was mapped to chromosome arm 2BS as a SSCP molecular marker, and was validated as tightly linked to a major QTL governing late heading of CASL2BS in all mapping populations. A significant dominance by additive effect of Ppd-B1 with the LUX gene located on 3AL was also detected. CS had more copies of Ppd-B1 than CASL2BS, implying that increased copy number could elevate the expression of Ppd-1 in CS, also increasing expression of LUX and FT genes and causing CS to have an earlier heading date than CASL2BS in long days.

  2. Localization of the Laevigatum powdery mildew resistance gene to barley chromosome 2 by the use of RFLP markers

    DEFF Research Database (Denmark)

    Giese, H.; Holm-Jensen, A.G.; Jensen, H.P.;

    1993-01-01

    The powdery mildew disease resistance gene Ml(La) was found to belong to a locus on barely chromosome 2. We suggest that this locus be designated MlLa. Linkage analysis was carried out on 72 chromosome-doubled, spring-type progeny lines from a cross between the winter var 'Vogelsanger Gold' and t......' and the spring var 'Alf'. A map of chromosome 2 spanning 119 cM and flanked by two peroxidase gene loci was constructed. In addition to the Laevigatum resistance locus the map includes nine RFLP markers, the two peroxidase gene loci and the six-row locus in barley....

  3. Reconstruction of ancestral chromosome architecture and gene repertoire reveals principles of genome evolution in a model yeast genus.

    Science.gov (United States)

    Vakirlis, Nikolaos; Sarilar, Véronique; Drillon, Guénola; Fleiss, Aubin; Agier, Nicolas; Meyniel, Jean-Philippe; Blanpain, Lou; Carbone, Alessandra; Devillers, Hugo; Dubois, Kenny; Gillet-Markowska, Alexandre; Graziani, Stéphane; Huu-Vang, Nguyen; Poirel, Marion; Reisser, Cyrielle; Schott, Jonathan; Schacherer, Joseph; Lafontaine, Ingrid; Llorente, Bertrand; Neuvéglise, Cécile; Fischer, Gilles

    2016-07-01

    Reconstructing genome history is complex but necessary to reveal quantitative principles governing genome evolution. Such reconstruction requires recapitulating into a single evolutionary framework the evolution of genome architecture and gene repertoire. Here, we reconstructed the genome history of the genus Lachancea that appeared to cover a continuous evolutionary range from closely related to more diverged yeast species. Our approach integrated the generation of a high-quality genome data set; the development of AnChro, a new algorithm for reconstructing ancestral genome architecture; and a comprehensive analysis of gene repertoire evolution. We found that the ancestral genome of the genus Lachancea contained eight chromosomes and about 5173 protein-coding genes. Moreover, we characterized 24 horizontal gene transfers and 159 putative gene creation events that punctuated species diversification. We retraced all chromosomal rearrangements, including gene losses, gene duplications, chromosomal inversions and translocations at single gene resolution. Gene duplications outnumbered losses and balanced rearrangements with 1503, 929, and 423 events, respectively. Gene content variations between extant species are mainly driven by differential gene losses, while gene duplications remained globally constant in all lineages. Remarkably, we discovered that balanced chromosomal rearrangements could be responsible for up to 14% of all gene losses by disrupting genes at their breakpoints. Finally, we found that nonsynonymous substitutions reached fixation at a coordinated pace with chromosomal inversions, translocations, and duplications, but not deletions. Overall, we provide a granular view of genome evolution within an entire eukaryotic genus, linking gene content, chromosome rearrangements, and protein divergence into a single evolutionary framework.

  4. Chromosomal painting and ZW sex chromosomes differentiation in Characidium (Characiformes, Crenuchidae

    Directory of Open Access Journals (Sweden)

    Artoni Roberto F

    2011-07-01

    Full Text Available Abstract Background The Characidium (a Neotropical fish group have a conserved diploid number (2n = 50, but show remarkable differences among species and populations in relation to sex chromosome systems and location of nucleolus organizer regions (NOR. In this study, we isolated a W-specific probe for the Characidium and characterized six Characidium species/populations using cytogenetic procedures. We analyzed the origin and differentiation of sex and NOR-bearing chromosomes by chromosome painting in populations of Characidium to reveal their evolution, phylogeny, and biogeography. Results A W-specific probe for efficient chromosome painting was isolated by microdissection and degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR amplification of W chromosomes from C. gomesi. The W probe generated weak signals dispersed on the proto sex chromosomes in C. zebra, dispersed signals in both W and Z chromosomes in C. lauroi and, in C. gomesi populations revealed a proximal site on the long arms of the Z chromosome and the entire W chromosome. All populations showed small terminal W probe sites in some autosomes. The 18S rDNA revealed distinctive patterns for each analyzed species/population with regard to proto sex chromosome, sex chromosome pair, and autosome location. Conclusions The results from dual-color fluorescence in situ hybridization (dual-color FISH using W and 18S rDNA probes allowed us to infer the putative evolutionary pathways for the differentiation of sex chromosomes and NORs, from structural rearrangements in a sex proto-chromosome, followed by gene erosion and heterochromatin amplification, morphological differentiation of the sex chromosomal pair, and NOR transposition, giving rise to the distinctive patterns observed among species/populations of Characidium. Biogeographic isolation and differentiation of sex chromosomes seem to have played a major role in the speciation process in this group of fish.

  5. Chromosome mis-segregation and cytokinesis failure in trisomic human cells.

    Science.gov (United States)

    Nicholson, Joshua M; Macedo, Joana C; Mattingly, Aaron J; Wangsa, Darawalee; Camps, Jordi; Lima, Vera; Gomes, Ana M; Dória, Sofia; Ried, Thomas; Logarinho, Elsa; Cimini, Daniela

    2015-05-05

    Cancer cells display aneuploid karyotypes and typically mis-segregate chromosomes at high rates, a phenotype referred to as chromosomal instability (CIN). To test the effects of aneuploidy on chromosome segregation and other mitotic phenotypes we used the colorectal cancer cell line DLD1 (2n = 46) and two variants with trisomy 7 or 13 (DLD1+7 and DLD1+13), as well as euploid and trisomy 13 amniocytes (AF and AF+13). We found that trisomic cells displayed higher rates of chromosome mis-segregation compared to their euploid counterparts. Furthermore, cells with trisomy 13 displayed a distinctive cytokinesis failure phenotype. We showed that up-regulation of SPG20 expression, brought about by trisomy 13 in DLD1+13 and AF+13 cells, is sufficient for the cytokinesis failure phenotype. Overall, our study shows that aneuploidy can induce chromosome mis-segregation. Moreover, we identified a trisomy 13-specific mitotic phenotype that is driven by up-regulation of a gene encoded on the aneuploid chromosome.

  6. Counseling parents before prenatal diagnosis: do we need to say more about the sex chromosome aneuploidies?

    Science.gov (United States)

    Lalatta, Faustina; Tint, G Stephen

    2013-11-01

    Sex chromosome trisomies (SCT), an extra X chromosome in females (triple X, XXX), males with an extra X chromosome (Klinefelter syndrome, XXY) or an extra Y chromosome (XYY) occur because of errors during meiosis and are relatively frequent in humans. Their identification has never been the goal of prenatal diagnosis (PD) but they almost never escape detection by any of the methods commonly in use. Despite recommendations and guide-lines which emphasize the importance of structured counseling before and after PD, most women remain unaware that testing for serious genetic abnormalities is more likely to uncover these trisomies. With the increasing use of PD more and more prospective parents receive a diagnosis of sex chromosome trisomies and are faced with the dilemma of whether to terminate the pregnancy or to carry it to term. Despite the dramatic and emotionally devastating consequences of having to make such a decision, they have little opportunity to consider in advance the possible outcomes of such a pregnancy and, rather than relying on their own feelings and judgements, are forced to depend on the advice of counseling professionals who may or may not themselves be fully aware of what having an extra sex chromosome can mean to the development of a child. We address here the principles of reproductive autonomy together with an analysis of the major issues that ought to be discussed with the parents before a PD is carried out in order to minimize detrimental effects caused by this unexpected finding.

  7. Physical mapping, expression analysis and polymorphism survey of resistance gene analogues on chromosome 11 of rice

    Indian Academy of Sciences (India)

    Irfan A Ghazi; Prem S Srivastava; Vivek Dalal; Kishor Gaikwad; Ashok K Singh; Tilak R Sharma; Nagendra K Singh; Trilochan Mohapatra

    2009-06-01

    Rice is the first cereal genome with a finished sequence and a model crop that has important syntenic relationships with other cereal species. The objectives of our study were to identify resistance gene analogue (RGA) sequences from chromosome 11 of rice, understand their expression in other cereals and dicots by in silico analysis, determine their presence on other rice chromosomes, and evaluate the extent of polymorphism and actual expression in a set of rice genotypes. A total of 195 RGAs were predicted and physically localised. Of these, 91.79% expressed in rice, and 51.28% expressed in wheat, which was the highest among other cereals. Among monocots, sugarcane showed the highest (78.92%) expression, while among dicots, RGAs were maximally expressed in Arabidopsis (11.79%). Interestingly, two of the chromosome 11-specific RGAs were found to be expressing in all the organisms studied. Eighty RGAs of chromosome 11 had significant homology with chromosome 12, which was the maximum among all the rice chromosomes. Thirty-one per cent of the RGAs used in polymerase chain reaction (PCR) amplification showed polymorphism in a set of rice genotypes. Actual gene expression analysis revealed post-inoculation induction of one RGA in the rice line IRBB-4 carrying the bacterial blight resistance gene Xa-4. Our results have implications for the development of sequence-based markers and functional validation of specific RGAs in rice.

  8. Stable X Chromosome Reactivation in Female Human Induced Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Tahsin Stefan Barakat

    2015-02-01

    Full Text Available In placental mammals, balanced expression of X-linked genes is accomplished by X chromosome inactivation (XCI in female cells. In humans, random XCI is initiated early during embryonic development. To investigate whether reprogramming of female human fibroblasts into induced pluripotent stem cells (iPSCs leads to reactivation of the inactive X chromosome (Xi, we have generated iPSC lines from fibroblasts heterozygous for large X-chromosomal deletions. These fibroblasts show completely skewed XCI of the mutated X chromosome, enabling monitoring of X chromosome reactivation (XCR and XCI using allele-specific single-cell expression analysis. This approach revealed that XCR is robust under standard culture conditions, but does not prevent reinitiation of XCI, resulting in a mixed population of cells with either two active X chromosomes (Xas or one Xa and one Xi. This mixed population of XaXa and XaXi cells is stabilized in naive human stem cell medium, allowing expansion of clones with two Xas.

  9. Y chromosome in Turner syndrome: detection of hidden mosaicism and the report of a rare X;Y translocation case.

    Science.gov (United States)

    Bispo, Adriana Valéria Sales; Burégio-Frota, Pollyanna; Oliveira dos Santos, Luana; Leal, Gabriela Ferraz; Duarte, Andrea Rezende; Araújo, Jacqueline; Cavalcante da Silva, Vanessa; Muniz, Maria Tereza Cartaxo; Liehr, Thomas; Santos, Neide

    2014-10-01

    Turner syndrome (TS) is a common genetic disorder in females associated with the absence of complete or parts of a second sex chromosome. In 5-12% of patients, mosaicism for a cell line with a normal or structurally abnormal Y chromosome is identified. The presence of Y-chromosome material is of medical importance because it results in an increased risk of developing gonadal tumours and virilisation. Molecular study and fluorescence in situ hybridisation approaches were used to study 74 Brazilian TS patients in order to determine the frequency of hidden Y-chromosome mosaicism, and to infer the potential risk of developing malignancies. Additionally, we describe one TS girl with a very uncommon karyotype 46,X,der(X)t(X;Y)(p22.3?2;q11.23) comprising a partial monosomy of Xp22.3?2 together with a partial monosomy of Yq11.23. The presence of cryptic Y-chromosome-specific sequences was detected in 2.7% of the cases. All patients with Y-chromosome-positive sequences showed normal female genitalia with no signs of virilisation. Indeed, the clinical data from Y-chromosome-positive patients was very similar to those with Y-negative results. Therefore, we recommend that the search for hidden Y-chromosome mosaicism should be carried out in all TS cases and not be limited to virilised patients or carriers of a specific karyotype.

  10. Differing requirements for RAD51 and DMC1 in meiotic pairing of centromeres and chromosome arms in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Olivier Da Ines

    Full Text Available During meiosis homologous chromosomes pair, recombine, and synapse, thus ensuring accurate chromosome segregation and the halving of ploidy necessary for gametogenesis. The processes permitting a chromosome to pair only with its homologue are not fully understood, but successful pairing of homologous chromosomes is tightly linked to recombination. In Arabidopsis thaliana, meiotic prophase of rad51, xrcc3, and rad51C mutants appears normal up to the zygotene/pachytene stage, after which the genome fragments, leading to sterility. To better understand the relationship between recombination and chromosome pairing, we have analysed meiotic chromosome pairing in these and in dmc1 mutant lines. Our data show a differing requirement for these proteins in pairing of centromeric regions and chromosome arms. No homologous pairing of mid-arm or distal regions was observed in rad51, xrcc3, and rad51C mutants. However, homologous centromeres do pair in these mutants and we show that this does depend upon recombination, principally on DMC1. This centromere pairing extends well beyond the heterochromatic centromere region and, surprisingly, does not require XRCC3 and RAD51C. In addition to clarifying and bringing the roles of centromeres in meiotic synapsis to the fore, this analysis thus separates the roles in meiotic synapsis of DMC1 and RAD51 and the meiotic RAD51 paralogs, XRCC3 and RAD51C, with respect to different chromosome domains.

  11. Inheritance of a ring 14 chromosome.

    Science.gov (United States)

    Riley, S B; Buckton, K E; Ratcliffe, S G; Syme, J

    1981-06-01

    A family is described in which the mother, her two live offspring, and a therapeutically aborted fetus each had a ring 14 chromosomes. The two children were mentally retarded and the mother's intelligence was at the lower end of the normal range. In addition, the mother had two spontaneous abortions, one of which was shown to be chromosomally normal.

  12. Inheritance of a ring 14 chromosome.

    OpenAIRE

    Riley, S B; Buckton, K E; Ratcliffe, S G; Syme, J.

    1981-01-01

    A family is described in which the mother, her two live offspring, and a therapeutically aborted fetus each had a ring 14 chromosomes. The two children were mentally retarded and the mother's intelligence was at the lower end of the normal range. In addition, the mother had two spontaneous abortions, one of which was shown to be chromosomally normal.

  13. Human male meiotic sex chromosome inactivation

    NARCIS (Netherlands)

    Vries, M. de; Vosters, S.; Merkx, G.F.M.; Hauwers, K.W.M. d'; Wansink, D.G.; Ramos, L.; Boer, P. de

    2012-01-01

    In mammalian male gametogenesis the sex chromosomes are distinctive in both gene activity and epigenetic strategy. At first meiotic prophase the heteromorphic X and Y chromosomes are placed in a separate chromatin domain called the XY body. In this process, X,Y chromatin becomes highly phosphorylate

  14. Dynamics of chromosome segregation in Escherichia coli

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck

    2007-01-01

    Since the 1960’es the conformation and segregation of the chromosome in Escherichia coli has been a subject of interest for many scientists. However, after 40 years of research, we still know incredibly little about how the chromosome is organized inside the cell, how it manages to duplicate...

  15. Chromosome condensation: weaving an untangled web.

    Science.gov (United States)

    Thadani, Rahul; Uhlmann, Frank

    2015-08-03

    The compaction of diffuse interphase chromatin into stable mitotic chromosomes enables the segregation of replicated DNA to daughter cells. Two new studies characterise, both in vivo and in vitro, the essential contribution of the vertebrate condensin complex to chromosome organisation.

  16. Chromosomal Aneuploidies and Early Embryonic Developmental Arrest

    Directory of Open Access Journals (Sweden)

    Maria Maurer

    2015-07-01

    Full Text Available Background: Selecting the best embryo for transfer, with the highest chance of achieving a vital pregnancy, is a major goal in current in vitro fertilization (IVF technology. The high rate of embryonic developmental arrest during IVF treatment is one of the limitations in achieving this goal. Chromosomal abnormalities are possibly linked with chromosomal arrest and selection against abnormal fertilization products. The objective of this study was to evaluate the frequency and type of chromosomal abnormalities in preimplantation embryos with developmental arrest. Materials and Methods: This cohort study included blastomeres of embryos with early developmental arrest that were biopsied and analyzed by fluorescence in-situ hybridization (FISH with probes for chromosomes 13, 16, 18, 21 and 22. Forty-five couples undergoing IVF treatment were included, and 119 arrested embryos were biopsied. All probes were obtained from the Kinderwunsch Zentrum, Linz, Austria, between August 2009 and August 2011. Results: Of these embryos, 31.6% were normal for all chromosomes tested, and 68.4% were abnormal. Eleven embryos were uniformly aneuploid, 20 were polyploid, 3 were haploid, 11 displayed mosaicism and 22 embryos exhibited chaotic chromosomal complement. Conclusion: Nearly 70% of arrested embryos exhibit chromosomal errors, making chromosomal abnormalities a major cause of embryonic arrest and may be a further explanation for the high developmental failure rates during culture of the embryos in the IVF setting.

  17. Genomic Dark Matter Illuminated: Anopheles Y Chromosomes.

    Science.gov (United States)

    Redmond, Seth N; Neafsey, Daniel E

    2016-08-01

    Hall et al. have strategically used long-read sequencing technology to characterize the structure and highly repetitive content of the Y chromosome in Anopheles malaria mosquitoes. Their work confirms that this important but elusive heterochromatic sex chromosome is evolving extremely rapidly and harbors a remarkably small number of genes.

  18. Non-disjunction of chromosome 13

    DEFF Research Database (Denmark)

    Bugge, Merete; Collins, Andrew; Hertz, Jens Michael

    2007-01-01

    recombination in both maternal MI and MII errors and the former is associated with a significant number of tetrads (33%) that are nullichiasmate, which do not appear to be a feature of normal chromosome 13 meiosis. This study supports the evidence for subtle chromosome-specific influences on the mechanisms...

  19. Paradigm Lost: The Human Chromosome Story.

    Science.gov (United States)

    Unger, Lawrence; Blystone, Robert V.

    1996-01-01

    Discusses whether the discovery in 1956 that humans have a chromosome number of 46, as opposed to 47 or 48 as previously thought, fits into a paradigm shift of the Kuhnian type. Concludes that Kuhn probably would not have considered the chromosome number shift to be large enough to be a focus for one of his paradigms. (AIM)

  20. Chromosome Segregation: Organizing Overlap at the Midzone

    NARCIS (Netherlands)

    Janson, M.E.; Tran, P.T.

    2008-01-01

    Sets of overlapping microtubules support the segregation of chromosomes by linking the poles of mitotic spindles. Recent work examines the effect of putting these linkages under pressure by the activation of dicentric chromosomes and sheds new light on the structural role of several well-known spind

  1. DETECTION OF CHROMOSOME ABERRATIONS IN TWELVE PRIMARY GASTRIC CANCERS BY DIRECT CHROMOSOME ANALYSIS AND FISH

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Direct chromosome analysis and FISH were performed on twelve primary gastric carcinomas. Two of them had simple chromosome changes: 48,XX, +8, +20, and 49, XY, +2, +8, +9, and the others had complicated chromosome changes, which includes much more numerical and structural chromosome aberrations. Frequent structural changes in the complicated types involved chromosome 7, 3, 1, 5 and 12 etc. The del 7q was noted in eight cases. The del (3p) and del (1p) were noted in six and five cases, respectively. The results provide some important clues for isolation of the genes related to gastric cancer.

  2. Small supernumerary marker chromosomes (sSMC) in humans; are there B chromosomes hidden among them

    OpenAIRE

    Ogilvie Caroline; Kosyakova Nadezda; Mrasek Kristin; Liehr Thomas; Vermeesch Joris; Trifonov Vladimir; Rubtsov Nikolai

    2008-01-01

    Abstract Background Small supernumerary marker chromosomes (sSMC) and B-chromosomes represent a heterogeneous collection of chromosomes added to the typical karyotype, and which are both small in size. They may consist of heterochromatic and/or euchromatic material. Also a predominance of maternal transmission was reported for both groups. Even though sSMC and B-chromosomes show some similarity it is still an open question if B-chromosomes are present among the heterogeneous group of sSMC. Ac...

  3. Buccal cell FISH and blood PCR-Y detect high rates of X chromosomal mosaicism and Y chromosomal derivatives in patients with Turner syndrome.

    Science.gov (United States)

    Freriks, Kim; Timmers, Henri J L M; Netea-Maier, Romana T; Beerendonk, Catharina C M; Otten, Barto J; van Alfen-van der Velden, Janiëlle A E M; Traas, Maaike A F; Mieloo, Hanneke; van de Zande, Guillaume W H J F L; Hoefsloot, Lies H; Hermus, Ad R M M; Smeets, Dominique F C M

    2013-09-01

    Turner syndrome (TS) is the result of (partial) X chromosome monosomy. In general, the diagnosis is based on karyotyping of 30 blood lymphocytes. This technique, however, does not rule out tissue mosaicism or low grade mosaicism in the blood. Because of the associated risk of gonadoblastoma, mosaicism is especially important in case this involves a Y chromosome. We investigated different approaches to improve the detection of mosaicisms in 162 adult women with TS (mean age 29.9 ± 10.3). Standard karyotyping identified 75 patients (46.3%) with a non-mosaic monosomy 45,X. Of these 75 patients, 63 underwent additional investigations including FISH on buccal cells with X- and Y-specific probes and PCR-Y on blood. FISH analysis of buccal cells revealed a mosaicism in 19 of the 63 patients (30.2%). In five patients the additional cell lines contained a (derivative) Y chromosome. With sensitive real-time PCR we confirmed the presence of this Y chromosome in blood in three of the five cases. Although Y chromosome material was established in ovarian tissue in two patients, no gonadoblastoma was found. Our results confirm the notion that TS patients with 45,X on conventional karyotyping often have tissue specific mosaicisms, some of which include a Y chromosome. Although further investigations are needed to estimate the risk of gonadoblastoma in patients with Y chromosome material in buccal cells, we conclude that FISH or real-time PCR on buccal cells should be considered in TS patients with 45,X on standard karyotyping.

  4. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted benzothiazole-azo... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.5340 Substituted benzothiazole-azo... to reporting. (1) The chemical substance identified generically as substituted...

  5. Advances in understanding paternally transmitted Chromosomal Abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Marchetti, F; Sloter, E; Wyrobek, A J

    2001-03-01

    Multicolor FISH has been adapted for detecting the major types of chromosomal abnormalities in human sperm including aneuploidies for clinically-relevant chromosomes, chromosomal aberrations including breaks and rearrangements, and other numerical abnormalities. The various sperm FISH assays have been used to evaluate healthy men, men of advanced age, and men who have received mutagenic cancer therapy. The mouse has also been used as a model to investigate the mechanism of paternally transmitted genetic damage. Sperm FISH for the mouse has been used to detect chromosomally abnormal mouse sperm, while the PAINT/DAPI analysis of mouse zygotes has been used to evaluate the types of chromosomal defects that can be paternally transmitted to the embryo and their effects on embryonic development.

  6. Review of the Y chromosome and hypertension

    Directory of Open Access Journals (Sweden)

    D. Ely

    2000-06-01

    Full Text Available The Y chromosome from spontaneously hypertensive rats (SHR has a locus that raises blood pressure 20-25 mmHg. Associated with the SHR Y chromosome effect is a 4-week earlier pubertal rise of testosterone and dependence upon the androgen receptor for the full blood pressure effect. Several indices of enhanced sympathetic nervous system (SNS activity are also associated with the SHR Y chromosome. Blockade of SNS outflow reduced the blood pressure effect. Salt sensitivity was increased by the Y chromosome as was salt appetite which was SNS dependent. A strong correlation (r = 0.57, P<0.001 was demonstrable between plasma testosterone and angiotensin II. Coronary collagen increased with blood pressure and the presence of the SHR Y chromosome. A promising candidate gene for the Y effect is the Sry locus (testis determining factor, a transcription factor which may also have other functions.

  7. Comparative analysis by chromosome painting of the sex chromosomes in arvicolid rodents.

    Science.gov (United States)

    Acosta, M J; Romero-Fernández, I; Sánchez, A; Marchal, J A

    2011-01-01

    Sex chromosome evolution in mammals has been extensively investigated through chromosome-painting analyses. In some rodent species from the subfamily Arvicolinae the sex chromosomes contain remarkable features such as giant size, a consequence of heterochromatic enlargement, or asynaptic behaviour during male meiosis. Here, we have made a comparative study of the sex chromosomes in 6 arvicolid species using different probes from the X and Y chromosomes of 3 species, in order to gain knowledge about intra- or interspecific preservation of euchromatic regions. Our results clearly reveal poor conservation of the euchromatic region of the Y chromosome within these species, while the euchromatin on the X chromosome is extremely well preserved. Furthermore, we detected no clear correlation between the synaptic/asynaptic behaviour of the sex chromosomes, and the presence or absence of sequence homology within their euchromatic regions. Notably, our study has shown a new relationship between the giant sex chromosomes of 2 species, Microtus agrestis and Microtus cabrerae, that is, both X and Y share a novel region of common sequences in the euchromatin that is not present in the other species analysed. This interspecific euchromatic conservation, limited to the giant sex chromosomes, could point towards a common evolutionary origin for the heterochromatic enlargement process that has characterized the evolution of the sex chromosomes in some arvicolid species.

  8. Energy Landscapes of Folding Chromosomes

    Science.gov (United States)

    Zhang, Bin

    The genome, the blueprint of life, contains nearly all the information needed to build and maintain an entire organism. A comprehensive understanding of the genome is of paramount interest to human health and will advance progress in many areas, including life sciences, medicine, and biotechnology. The overarching goal of my research is to understand the structure-dynamics-function relationships of the human genome. In this talk, I will be presenting our efforts in moving towards that goal, with a particular emphasis on studying the three-dimensional organization, the structure of the genome with multi-scale approaches. Specifically, I will discuss the reconstruction of genome structures at both interphase and metaphase by making use of data from chromosome conformation capture experiments. Computationally modeling of chromatin fiber at atomistic level from first principles will also be presented as our effort for studying the genome structure from bottom up.

  9. New Y chromosomes and early stages of sex chromosome differentiation: sex determination in Megaselia

    Indian Academy of Sciences (India)

    Walther Traut

    2010-09-01

    The phorid fly Megaselia scalaris is a laboratory model for the turnover and early differentiation of sex chromosomes. Isolates from the field have an XY sex-determining mechanism with chromosome pair 2 acting as X and Y chromosomes. The sex chromosomes are homomorphic but display early signs of sex chromosome differentiation: a low level of molecular differences between X and Y. The male-determining function $(M)$, maps to the distal part of the Y chromosome’s short arm. In laboratory cultures, new Y chromosomes with no signs of a molecular differentiation arise at a low rate, probably by transposition of to these chromosomes. Downstream of the primary signal, the homologue of the Drosophila doublesex (dsx) is part of the sex-determining pathway while Sex-lethal (Sxl), though structurally conserved, is not.

  10. Type Substitution for Object-Oriented Programming

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff; Palsberg, Jens

    1990-01-01

    Genericity allows the substitution of types in a class. This is usually obtained through parameterized classes, although they are inflexible since any class can be inherited but is not in itself parameterized. We suggest a new genericity mechanism, type substitution, which is a subclassing concep...

  11. Biomechanical properties of four dermal substitutes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Guo-an; NING Fang-gang; ZHAO Nan-ming

    2007-01-01

    @@ Many kinds of cell-free dermal substitutes have been developed during the past several years, however,their biomechanical properties, including hysteresis,stress relaxation, creep, and non-linear stress-strain, are still unknown. In this study, we tested these biomechanical characteristics of four dermal substitutes,and compared them with those of fresh human skin (FHS).

  12. 24 CFR 235.206 - Substitute mortgagors.

    Science.gov (United States)

    2010-04-01

    ... MORTGAGE INSURANCE AND ASSISTANCE PAYMENTS FOR HOME OWNERSHIP AND PROJECT REHABILITATION Contract Rights and Obligations-Homes for Lower Income Families § 235.206 Substitute mortgagors. (a) Selling mortgagor... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Substitute mortgagors....

  13. PERFORMANCE OF PULVERIZED SLAG-SUBSTITUTED CEMENT

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The Portland cement is equivalently substituted by slag micropowders with various specific areas. The workability,activity and acid-corrosion resistance of the slag-substituted cements are investigated,the activation of gypsum is discussed,also the porosity and pore distribution of mortars of the slag micropowders cement are determined by mercury intrusion porosimetry.

  14. Multisensory integration, sensory substitution and visual rehabilitation

    DEFF Research Database (Denmark)

    Proulx, Michael J; Ptito, Maurice; Amedi, Amir

    2014-01-01

    Sensory substitution has advanced remarkably over the past 35 years since first introduced to the scientific literature by Paul Bach-y-Rita. In this issue dedicated to his memory, we describe a collection of reviews that assess the current state of neuroscience research on sensory substitution...

  15. Synthesis and antitumor activities of novel 1,4-substituted phthalazine derivatives

    Institute of Scientific and Technical Information of China (English)

    Shu Lan Zhang; Ya Jing Liu; Yan Fang Zhao; Qiu Ting Guo; Ping Gong

    2010-01-01

    A series of 1,4-substituted phthalazine derivatives were designed and synthesized.All the prepared compounds were screened for their cytotoxic activities against A549,HT-29 and MDA-MB-231 cell lines in vitro.Among them,compounds 7a-7h showed excellent selectivity for MDA-MB-231 cell line with IC50 values from 1 nmol/L to 0.92 μmol/L.A preliminary SAR study of these derivatives was performed.

  16. Novel gene acquisition on carnivore Y chromosomes.

    Directory of Open Access Journals (Sweden)

    William J Murphy

    2006-03-01

    Full Text Available Despite its importance in harboring genes critical for spermatogenesis and male-specific functions, the Y chromosome has been largely excluded as a priority in recent mammalian genome sequencing projects. Only the human and chimpanzee Y chromosomes have been well characterized at the sequence level. This is primarily due to the presumed low overall gene content and highly repetitive nature of the Y chromosome and the ensuing difficulties using a shotgun sequence approach for assembly. Here we used direct cDNA selection to isolate and evaluate the extent of novel Y chromosome gene acquisition in the genome of the domestic cat, a species from a different mammalian superorder than human, chimpanzee, and mouse (currently being sequenced. We discovered four novel Y chromosome genes that do not have functional copies in the finished human male-specific region of the Y or on other mammalian Y chromosomes explored thus far. Two genes are derived from putative autosomal progenitors, and the other two have X chromosome homologs from different evolutionary strata. All four genes were shown to be multicopy and expressed predominantly or exclusively in testes, suggesting that their duplication and specialization for testis function were selected for because they enhance spermatogenesis. Two of these genes have testis-expressed, Y-borne copies in the dog genome as well. The absence of the four newly described genes on other characterized mammalian Y chromosomes demonstrates the gene novelty on this chromosome between mammalian orders, suggesting it harbors many lineage-specific genes that may go undetected by traditional comparative genomic approaches. Specific plans to identify the male-specific genes encoded in the Y chromosome of mammals should be a priority.

  17. The X chromosome and immune associated genes.

    Science.gov (United States)

    Bianchi, Ilaria; Lleo, Ana; Gershwin, M Eric; Invernizzi, Pietro

    2012-05-01

    The X chromosome is known to contain the largest number of immune-related genes of the whole human genome. For this reason, X chromosome has recently become subject of great interest and attention and numerous studies have been aimed at understanding the role of genes on the X chromosome in triggering and maintaining the autoimmune aggression. Autoimmune diseases are indeed a growing heath burden affecting cumulatively up to 10% of the general population. It is intriguing that most X-linked primary immune deficiencies carry significant autoimmune manifestations, thus illustrating the critical role played by products of single gene located on the X chromosome in the onset, function and homeostasis of the immune system. Again, the plethora of autoimmune stigmata observed in patients with Turner syndrome, a disease due to the lack of one X chromosome or the presence of major X chromosome deletions, indicate that X-linked genes play a unique and major role in autoimmunity. There have been several reports on a role of X chromosome gene dosage through inactivation or duplication in women with autoimmune diseases, for example through a higher rate of circulating cells with a single X chromosome (i.e. with X monosomy). Finally, a challenge for researchers in the coming years will be to dissect the role for the large number of X-linked microRNAs from the perspective of autoimmune disease development. Taken together, X chromosome might well constitute the common trait of the susceptibility to autoimmune diseases, other than to explain the female preponderance of these conditions. This review will focus on the available evidence on X chromosome changes and discuss their potential implications and limitations.

  18. Frequent gene conversion events between the X and Y homologous chromosomal regions in primates

    Directory of Open Access Journals (Sweden)

    Hirai Hirohisa

    2010-07-01

    Full Text Available Abstract Background Mammalian sex-chromosomes originated from a pair of autosomes. A step-wise cessation of recombination is necessary for the proper maintenance of sex-determination and, consequently, generates a four strata structure on the X chromosome. Each stratum shows a specific per-site nucleotide sequence difference (p-distance between the X and Y chromosomes, depending on the time of recombination arrest. Stratum 4 covers the distal half of the human X chromosome short arm and the p-distance of the stratum is ~10%, on average. However, a 100-kb region, which includes KALX and VCX, in the middle of stratum 4 shows a significantly lower p-distance (1-5%, suggesting frequent sequence exchanges or gene conversions between the X and Y chromosomes in humans. To examine the evolutionary mechanism for this low p-distance region, sequences of a corresponding region including KALX/Y from seven species of non-human primates were analyzed. Results Phylogenetic analysis of this low p-distance region in humans and non-human primate species revealed that gene conversion like events have taken place at least ten times after the divergence of New World monkeys and Catarrhini (i.e., Old World monkeys and hominoids. A KALY-converted KALX allele in white-handed gibbons also suggests a possible recent gene conversion between the X and Y chromosomes. In these primate sequences, the proximal boundary of this low p-distance region is located in a LINE element shared between the X and Y chromosomes, suggesting the involvement of this element in frequent gene conversions. Together with a palindrome on the Y chromosome, a segmental palindrome structure on the X chromosome at the distal boundary near VCX, in humans and chimpanzees, may mediate frequent sequence exchanges between X and Y chromosomes. Conclusion Gene conversion events between the X and Y homologous regions have been suggested, mainly in humans. Here, we found frequent gene conversions in the

  19. Aluminum substitution in goethite in lake ore

    Directory of Open Access Journals (Sweden)

    Carlson, L.

    1995-06-01

    Full Text Available The extent of substitution of Fe by Al in goethite in 32 lake ore samples collected from 11 lakes in Finland varied between 0 and 23 mol-%. The data indicated a negative relationship between Al-substitution and the particle size of lake ore. Differences in the Al-substitution were apparent between sampling sites, suggesting that kinetic and environmental variation in lake ore formation influences the substitution. Non-substituted goethite is formed in coarse-grained sediments with locally high concentrations of Fe due to iron-rich springs. Unit cell edge lengths and volumes of goethite varied as function of Al-subsitution but deviated from the Vegard relationship towards higher values.

  20. Kondo-effect of substitutional cobalt impurities at copper surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Wahl, P; Diekhoener, L; Schneider, M A; Kern, K [Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstr. 1, D-70569 Stuttgart (Germany); S