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Sample records for chromosome substitution lines

  1. Cotton Chromosome Substitution Lines Crossed with Cultivars: Genetic Model Evaluation and Seed Trait Analyses

    Science.gov (United States)

    Seed from Upland cotton, Gossypium hirsutum L., provides a desirable and important nutrition profile. In this study, six seed traits (protein content, oil content, seed hull fiber content, seed index, seed volume, embryo percentage) for F3 hybrids of 13 cotton chromosome substitution lines crossed w...

  2. QTL Detection for Rice Grain Shape Using Chromosome Single SegmentSubstitution Lines

    Institute of Scientific and Technical Information of China (English)

    LI Sheng-qiang; CUI Guo-kun,; GUAN Cheng-ran; WANG Jun,; LIANG Guo-hua

    2011-01-01

    Rice grain shape is one of the important factors affecting grain quality and yield,but it is liable to be influenced by genetic backgrounds and environments.The chromosome single segment substitution lines (SSSLs) in rice have been considered as ideal populations to identify the quantitative trait loci (QTLs).In this study,22 QTLs affecting rice grain shape were detected to be distributed on eight chromosomes except chromosomes 6,9,11 and 12 by using SSSLs.Among them,seven QTLs conditioned grain length,six conditioned grain width,five affected grain length-width ratio and four controlled grain thickness.

  3. Development of Gossypium barbadense chromosome segment substitution lines in the genetic standard line TM-1 of Gossypium hirsutum

    Institute of Scientific and Technical Information of China (English)

    WANG Peng; DING YeZhang; LU QiongXian; GUO WangZhen; ZHANG TianZhen

    2008-01-01

    Chromosome segment substitution lines (CSSL) consist of a battery of near-isogenic lines that have been developed and cover the entire genome of some crops. With the exception of one homozygous chromosome segment transferred from a donor parent, the remaining genome of each CSSL line is the same as the recipient parent. It is an ideal material for genome research and particularly QTL mapping. In the present study, we first developed one set of CSSL lines using G. Hirsutum acc. TM-1 (the genetic standard), as the recipient parent and G. Barbadense cv. Hai7124 as the donor parent using molecular assisted-selection in BC5S1-3 generations. The CSSL consisted of 330 different lines, in which 1-4 dif-ferent lines had the same or overlapping substituted segments. The genetic length of the substituted segments covered 5271.9 cM with an average segment distance of 10.9 cM, 1.5 times the total genetic length of Upland cotton (3514.6 cM). The substituted segments of each line varied in length, ranging from 3.5 cM for the shortest segment to 23.2 cM in the longest segment. Our CSSL have not yet to cover the entire tetraploid cotton genome, due to the absence of some donor parent interval segments.

  4. Density-independent population projection trajectories of chromosome-substituted lines resistant and susceptible to organophosphate insecticides in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Miyo Takahiro

    2004-11-01

    Full Text Available Abstract Background Seasonal fluctuations in susceptibility to organophosphate insecticides were observed in the Katsunuma population of Drosophila melanogaster for two consecutive years; susceptibility to three organophosphates tended to increase in the fall. To examine the hypothesis that variation in fitness among resistant and susceptible genotypes could trigger the change of genetic constitution within the fall population, we investigated density-independent population projection trajectories starting from single adult females with characteristics of chromosome-substituted lines resistant and susceptible to the three organophosphates. Results Density-independent population projection trajectories, expressed as the ratios of the number of each chromosome-substituted line to that of line SSS, for which all chromosomes were derived from the susceptible line, showed significant declines in numbers with time for all the resistant chromosome-substituted lines. Conclusion The declining tendency in the density-independent population projection trajectories of the resistant chromosome-substituted lines could explain the simultaneous decline in the levels of resistance to the three organophosphates, observed in the Katsunuma population in the fall.

  5. 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 ...

  6. Cytogenetic and molecular identification of small-segment chromosome translocation lines from wheat-rye substitution lines to create wheat germplasm with beneficial traits

    OpenAIRE

    Song, Wei-Fu; Ding, Hai-Yan; Zhang, Xiao-Mei; Li, Ji-Lin; Xiao, Zhi-Min; Xin, Wen-Li; Song, Qing-Jie; Zhao, Hai-Bin; Zhang, Yan-bin; Zhang, Chun-Li

    2014-01-01

    ABSTRACT Intergeneric crop plant hybrid lines with small-segment chromosome translocations are very useful in plant genetic research and breeding. In this study, to create small-segment chromosome translocations with beneficial agronomic characters, the progeny of wheat-rye substitution lines 5R/5A and 6R/6A were selected from generations F2 to F5 for rye-specific characteristics. A PCR primer and specific simple sequence repeat marker for rye were used in F5 populations to detect rye chromat...

  7. 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.

  8. 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.

  9. 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.

  10. 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

  11. Salt-responsive mechanisms in chromosome segment substitution lines of rice (Oryza sativa L. cv. KDML105).

    Science.gov (United States)

    Nounjan, Noppawan; Siangliw, Jonaliza L; Toojinda, Theerayut; Chadchawan, Supachitra; Theerakulpisut, Piyada

    2016-06-01

    Two chromosome segment substitution lines of Khao Dawk Mali 105 (KDML105) rice that carry quantitative trait loci for drought tolerance located on chromosome 8 (DT-QTL8) designated CSSL8-94 and CSSL8-116 were investigated for co-expression network and physiological responses to salinity compared to their parents (KDML105; drought and salt sensitive recurrent parent, and DH103; drought tolerant QTL donor). These CSSL lines show different salt-response traits under salt stress (CSSL8-94 shows higher tolerance than CSSL8-116) and possess different segments of DT-QTL8. To identify specific biological process(es) associated with salt-stress response, co-expression network analysis was constructed from each DT-QTL segment. To evaluate differential physiological mechanisms responding to salt stress, all rice lines/cultivar were grown for 21 d in soils submerged in nutrient solutions, then subjected to 150 mM NaCl for 7 d. Physiological parameters related to co-expression network analysis (photosynthetic parameters) and salt responsive parameters (Na(+)/K(+) ratio, proline content, malondialdehyde and ascorbate peroxidase activity; EC1.11.1.1) were investigated along with the expression analysis of related genes. Physiological responses under salt stress particularly photosynthesis-related parameters of CSSL8-94 were similar to DH103, whereas those of CSSL8-116 were similar to KDML105. Moreover, expression levels of photosynthesis-related genes selected from the co-expression networks (Os08g41460, Os08g44680, Os06g01850, Os03g07300 and Os02g42570) were slightly decreased or stable in CSSL8-94 and DH103 but were dramatically down-regulated in CSSL8-116 and KDML105. These differential responses may contribute to the photosynthesis systems of CSSL8-94 being less damaged under salt stress in comparison to those of CSSL8-116. It can be concluded that the presence of the specific DT-QTL8 segment in CSSL8-94 not only confers drought tolerant traits but also enhances its salt

  12. Identification of Chromosome Segment Substitution Lines of Gossypium barbadense Introgressed in G. hirsutum and Quantitative Trait Locus Mapping for Fiber Quality and Yield Traits.

    Science.gov (United States)

    Zhai, Huanchen; Gong, Wankui; Tan, Yunna; Liu, Aiying; Song, Weiwu; Li, Junwen; Deng, Zhuying; Kong, Linglei; Gong, Juwu; Shang, Haihong; Chen, Tingting; Ge, Qun; Shi, Yuzhen; Yuan, Youlu

    2016-01-01

    Chromosome segment substitution lines MBI9804, MBI9855, MBI9752, and MBI9134, which were obtained by advanced backcrossing and continuously inbreeding from an interspecific cross between CCRI36, a cultivar of upland cotton (Gossypium hirsutum) as the recurrent parent, and Hai1, a cultivar of sea island cotton (G. barbadense) as the donor parent, were used to construct a multiple parent population of (MBI9804×MBI9855)×(MBI9752×MBI9134). The segregating generations of double-crossed F1 and F2 and F2:3 were used to map the quantitative trait locus (QTL) for fiber quality and yield-related traits. The recovery rate of the recurrent parent CCRI36 in the four parental lines was from 94.3%-96.9%. Each of the parental lines harbored 12-20 introgressed segments from Hai1across 21 chromosomes. The number of introgressed segments ranged from 1 to 27 for the individuals in the three generations, mostly from 9 to 18, which represented a genetic length of between 126 cM and 246 cM. A total of 24 QTLs controlling fiber quality and 11 QTLs controlling yield traits were detected using the three segregating generations. These QTLs were distributed across 11 chromosomes and could collectively explain 1.78%-20.27% of the observed phenotypic variations. Sixteen QTLs were consistently detected in two or more generations, four of them were for fiber yield traits and 12 were for fiber quality traits. One introgressed segment could significantly reduce both lint percentage and fiber micronaire. This study provides useful information for gene cloning and marker-assisted breeding for excellent fiber quality. PMID:27603312

  13. Developing high throughput genotyped chromosome segment substitution lines based on population whole-genome re-sequencing in rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Gu Minghong

    2010-11-01

    Full Text Available Abstract Background Genetic populations provide the basis for a wide range of genetic and genomic studies and have been widely used in genetic mapping, gene discovery and genomics-assisted breeding. Chromosome segment substitution lines (CSSLs are the most powerful tools for the detection and precise mapping of quantitative trait loci (QTLs, for the analysis of complex traits in plant molecular genetics. Results In this study, a wide population consisting of 128 CSSLs was developed, derived from the crossing and back-crossing of two sequenced rice cultivars: 9311, an elite indica cultivar as the recipient and Nipponbare, a japonica cultivar as the donor. First, a physical map of the 128 CSSLs was constructed on the basis of estimates of the lengths and locations of the substituted chromosome segments using 254 PCR-based molecular markers. From this map, the total size of the 142 substituted segments in the population was 882.2 Mb, was 2.37 times that of the rice genome. Second, every CSSL underwent high-throughput genotyping by whole-genome re-sequencing with a 0.13× genome sequence, and an ultrahigh-quality physical map was constructed. This sequencing-based physical map indicated that 117 new segments were detected; almost all were shorter than 3 Mb and were not apparent in the molecular marker map. Furthermore, relative to the molecular marker-based map, the sequencing-based map yielded more precise recombination breakpoint determination and greater accuracy of the lengths of the substituted segments, and provided more accurate background information. Third, using the 128 CSSLs combined with the bin-map converted from the sequencing-based physical map, a multiple linear regression QTL analysis mapped nine QTLs, which explained 89.50% of the phenotypic variance for culm length. A large-effect QTL was located in a 791,655 bp region that contained the rice 'green revolution' gene. Conclusions The present results demonstrated that high

  14. 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.

  15. 利用置换系鉴定棉花第16染色体上的产量及纤维品质QTLs%Identification of QTLs Affecting Yield and Fiber Properties in Chromosome 16 in Cotton Using Substitution Line

    Institute of Scientific and Technical Information of China (English)

    Li-Hua REN; Wang-Zhen GUO; Tian-Zhen ZHANG

    2002-01-01

    @@ Gossypium hirsutum L. , one of the two cultivated tetraploid species in cotton, is characterized by its high yield and wide adaptation, while G. barbadense L., another cultivated one, by its super fiber properties.Substitution line in which one pair of intact chromosomes of TM-1 (G. hirsutum L. ) was replaced by one pair of homozygous chromosome of 3-79 (G. barbadense L. ) is an excellent material for genetic research and molecular tagging. In this study, substitution line 16(Sub16)was used to evaluate the performance of the 16th chromosome in G.

  16. 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.

  17. Using a set of TeQing-into-Lemont chromosome segment substitution lines for fine mapping QTL: Case studies on sheath blight resistance, spreading culm, and mesocotyl elongation

    Science.gov (United States)

    A set of backcross introgression lines containing portions of the TeQing genome now introgressed into a Lemont genetic background allows us to fine map rice QTL, and measure their breeding value within U.S. rice genetic and field environments....

  18. The Study on Induced Chromosome Translocation by Hybridized Among Wheat-Rye Disomic Substitution Lines%小麦-黑麦二体代换系间杂交诱导染色体易位的研究

    Institute of Scientific and Technical Information of China (English)

    李宇欣; 张利国; 厉永鹏; 李集临; 张延明

    2013-01-01

    Hybridization among wheat-rye disomic substitutions is an important way to induce wheat-rye translocation, which has important theory value and practical significance. In this study, translocation lines were bred from hybrid offspring that the hybridization of wheat-rye disomic substitution between 1R/1D, 5R/5A and 6R/6A. The results showed that F1 had 19 bivalents and 4 univalents in meiosis; homoeologous chromosome pairing and chromosome translocation phenomenon appeared. In F2, 24 common wheat types with rye traits plants were detected by genome in situ hybridization and obtained 10 plants with chromosomal translocation, and the translocation frequency was 41.6%. Translocation lines was 06-15-7, 06-16-3, 06-16-5, 06-16-7, 06-16-8, 06-17-7, 0617-11, 06-17-15, 06-17-16 and 06-18-5, respectively. Because parent selection and testing plant had a definite purpose, translocation plants could have a practical applications as well as the basis material for wheat breeding.%小麦-黑麦二体代换系间杂交,是诱导小麦-黑麦染色体易位的重要途径,有理论与应用价值。利用小麦-黑麦二体代换系1R/1D与5R/5A、6R/6A杂交,从杂交后代中,选育易位系。结果表明,F1减数分裂有19个二价体、4个单价体,有部分同源染色体配对和染色体易位现象;F2对普通小麦类型带有黑麦性状的24株杂交材料,进行原位杂交检测,共检测出10株有染色体易位,易位频率为41.6%。易位株系为:06-15-7、06-16-3、06-16-5、06-16-7、06-16-8、06-17-7、0617-11、06-17-15、06-17-16、06-18-5。由于亲本选配与植株检测有一定的目的性,易位植株均表现有应用价值,可作为小麦品种选育的基础材料。

  19. 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, 2...... occurred during the evolution of the two species. Intergenomic introgression was observed in the progenies of the addition lines. The introgression of an entire B. alboglabra marker synteny group into the B. campestris genome implied the possible occurrence of interspecific chromosomal substitution....

  20. Study on Homoeologous Chromosome Pairing and Translocation Induced by 5A/5R×6A/6R Wheat-Rye Substitution Lines%小麦-黑麦代换系5A/5R与6A/6R杂交诱导同祖染色体配对与易位的研究

    Institute of Scientific and Technical Information of China (English)

    李集临; 王晓萍; 钟丽; 徐香玲

    2006-01-01

    利用两个小麦-黑麦异源双代换系DS 5A/5R与DS 6A/6R杂交,探讨同祖染色体配对的可能性与创制小麦黑麦异源易位系.在方法上对杂种F1的减数分裂行为进行研究,观察5R与5A、6R与6A配对频率,探讨同祖染色体配对规律.实验结果看到:杂交F1减数分裂中有22.91%的花粉母细胞有小麦染色体(ABD组)与黑麦染色体(R组)发生同祖配对.在F2及以后世代,通过染色体C分带、原位杂交检测,选择小麦-黑麦易位系.在F2代的45株中检测到9株有易位,易位频率为20%,是目前小麦-黑麦染色体易位频率最高的.染色体易位有的来源于同祖配对的交换,有的来源于单价体错分裂或断裂的重建.%This article aims to study the homoeologous chromosome pairing and translocation induced by 5A/5R×6A/6R wheat-rye substitution lines. To clarify the mechanism of homoeologous chromosome pairing and create wheat-rye translocation lines, two wheat-rye substitution lines, 5A/5R and 6A/6R were crossed. The chromosome behavior of pollen mother cells (PMCs) in meiosis was investigated in hybrid F1. Homoeologous chromosome pairing between wheat and rye occurred in 22.9 1% of PMC. Wheat-rye translocation lines were identified via C-banding and in situ hybridization (GISH) in hybrid F2 and later generations. In F2 generation, translocations happened in 9 of 45 plants, reached to 20%. These translocation lines were generated from homoeologous chromosome pairing, or mis-division and reconstruction of univalent chromosomes.

  1. 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...

  2. The Effect of Phosphorus Deficiency Stress on Soluble Sugar Content and Soluble Protein Content and Chromosome of Wheat Substitution Lines%低磷胁迫对小麦代换系可溶性糖和可溶性蛋白含量的影响及染色体效应

    Institute of Scientific and Technical Information of China (English)

    郑金凤; 白志英; 李存东; 米少艳; 刘永霞

    2013-01-01

    Wheat substitution lines between Chinese Spring and Synthetic 6x under the treatments of phosphorus deficiency stress and phosphorus normal ( control) in different developing stages were studied to research the effect of phosphorus deficiency stress on soluble sugar content and soluble protein content and locate the gene controlling soluble sugar content and soluble protein content. The results showed that soluble sugar content and soluble protein content reduced under phosphorus deficiency stress in different developing stages;The genes promoting soluble sugar content might be located on 2A,3A,5B,7D chromosome of Synthetic 6x,and that the genes promoting soluble protein content might be located on 3A chromosome.%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孕穗期、开花期、灌浆期旗叶的可溶性糖和可溶性蛋白含量,研究低磷胁迫对相关生理性状的影响,并对控制可溶性糖和可溶性蛋白含量的相关基因进行染色体定位.结果表明,低磷胁迫下,中国春-Synthetic 6x染色体代换系及其亲本的可溶性糖和可溶性蛋白含量在测定的各生育时期中明显低于对照;Synthetic 6x的2A、3A、5B、7D染色体上可能存在促进可溶性糖含量增加的基因;3A染色体上可能存在诱导可溶性蛋白含量增加的基因.

  3. QTL Mapping for Rice RVA Properties Using Chromosome Segment Substitution Lines Derived from A Cross between Koshihikari and 9311%越光/9311染色体片段置换系的构建及稻米黏滞性谱特征值QTL分析

    Institute of Scientific and Technical Information of China (English)

    邵昕; 陈忠明; 刘正辉; 丁承强; 唐设; 李刚华; 王绍华; 丁艳锋

    2015-01-01

    This study was performed to de velop chromosome segment substitution lines using indic a recipient 9311 and j ap onic a donor Koshihikari, and thereby to map QTLs for rice RVA properties, with the aim of dissecting the genetic foundation of rice eating and cooking quality. With Koshihikari as donor and 9311 as recipient, a total of 138 Chromosome Segment Substitution Lines (CSSLs) had been developed by marker-assisted selection. And parameters including Peak Paste Viscosity (PKV), Hot Paste Viscosity (HPV), Cool Paste Viscosity (CPV), Breakdown Viscosity (BDV), Setback Viscosity (SBV), Consistence Viscosity (CSV), Pasting Temperature (PT) were measured by Rapid Viscosity Analyzer (RVA). The resulting CSSLs cover about 89%of rice genome. Most of CSSLs cover segments from donor parent were less than five, the number of single segment substitution lines was 51 and its coverage of CSSLs was 36.95%. Ten QTLs were identified on chromosome 1, 2, 3, 4, 5 and 9 using CSSLs. Most of these QTLs have been reported previously, but q BDV 1, q PT4.1, q PT4.2 and q CSV 3 were not to be reported yet. The qHPV-2 in an interval of RM341-RM525 and qBDV-2 in an interval of RM341-RM525 were involved in amylopectin synthesis. In summary, a set of chromosome segment substitution lines were created and QTL affecting RVA profiles was detected initially, thus providing ideal material for improvement of cooking and eating quality in rice.%研究以籼稻品种9311为受体亲本,粳稻品种越光为供体亲本构建染色体片段置换系(CSSLs)并对RVA谱特征值进行QTL定位,为稻米蒸煮食味品质的遗传改良创造理想条件。研究利用612对SSR标记对亲本(越光和9311)进行多态性筛选,使用检测出的多态性引物对染色体片段置换系株系进行鉴定。共鉴定出138个株系,并构成染色体片段置换系。该染色体片段置换系的水稻全基因组覆盖率达到89%,置换系群体中超过80%的株系携带的供体

  4. 利用置换系检测棉花第16染色体的产量、纤维品质QTLs%Identification of Quantitative Trait Loci (QTLs) Affecting Yield and Fiber Properties in Chromosome 16 in Cotton Using Substitution Line

    Institute of Scientific and Technical Information of China (English)

    任立华; 郭旺珍; 张天真

    2002-01-01

    陆地棉(Gossypium hirsutum L.)和海岛棉(Gossypium barbadense L.)是两个栽培四倍体棉种.前者产量高、适应性广,后者纤维品质优良.置换了海岛棉一对染色体的陆地棉置换系是研究海陆杂种此对染色体上基因互作的优异材料.在对第16染色体的置换系(简称Sub 16)进行遗传评价的基础上,利用(TM-1×Sub 16)F2∶3家系对位于第16染色体上的重要农艺性状进行遗传分析,发现第16染色体上有铃重、衣分、衣指、纤维长度、第一果枝节位的QTLs 各2个,纤维伸长率、开花天数的QTL各 1个,没有检测到子指、纤维强度、麦克隆值的QTL.在构建第16染色体的RAPD、SSR分子标记连锁图基础上,利用分子标记对相应重要农艺性状进行区间作图,检测到铃重、开花天数、纤维长度、纤维伸长率的QTL各1个,在F2∶3株系群体中能解释的表型变异分别为15.2%、12.1%、19.7%和11.7%;检测到2个衣指QTLs,在F2∶3株系群体中能解释的表型变异分别为11.6%和41.9%;检测到3个衣分QTLs,在F2∶3株系群体中能解释的表型变异分别为8.7%、9.6%和29.2%.单标记检测到铃重、开花天数的QTL各1个,在F2∶3株系群体中能解释的表型变异分别为1.60%和4.63%.证明了第16染色体与铃重、衣分、衣指、纤维长度、纤维伸长率、开花天数等性状的关系.%Gossypium hirsutum L. and G. barbadense L. are the two cultivated tetraploid species of cotton. The first is characterized by a high yield and wide adaptation, and the second by its super fiber property. Substitution line in which a pair of intact chromosomes of TM-1 (G. hirsutum) were replaced by a pair of homozygous chromosomes of 3-79 (G. barbadense) is an excellent material for genetic research and molecular tagging. In this study, substitution line 16 (Sub 16) was used to evaluate the performance of the 16th chromosome in G. barbadense in TM-1 background. The genetic analysis using the major gene

  5. Mapping of QTLs for Rice RVA Properties Using High-throughput Re-sequenced Chromosome Segment Substitution Lines%利用重测序的水稻染色体片段代换系定位控制稻米淀粉黏滞性谱QTL

    Institute of Scientific and Technical Information of China (English)

    张昌泉; 胡冰; 朱孔志; 张华; 冷亚麟; 汤述翥; 顾铭洪; 刘巧泉

    2013-01-01

    The RVA profile is one of the important factors for rice cooking and eating quality evaluation, and it would be of great significance to identify new quantitative trail loci (QTLs) for RVA profile for improvement of rice quality. With Nipponbare as recipient and 9311 as donor, a population with 38 chromosome segment substitution lines (CSSLs) had been developed and subsequently genotyped by high-throughput resequencing strategy. The population with their parents similar in apparent amylose content was used for mapping QTLs of RVA properties including peak paste viscosity (PKV), hot paste viscosity (HPV), cool paste viscosity (CPV), breakdown viscosity (BDV), setback viscosity (SBV), consistence viscosity (CSV), peak time (PeT) and pasting temperature (PaT) in two years and two environments. The QTL analysis was carried out by using one-way ANOVA and Dunnett' s test, and stable QTLs were identified in both two years and two environments. 10 stable QTLs, qPKV2. 1 , qPKV5. 1 , qPKV7. 1 , qPKVS.1, qHPV5. 1, qHPV7. 1, qCPV5. 1, qCPV7. 1, qSBV2. 1 and qSBV7. 1 were identified in the chromosome 2, 5, 7 and 8, respectively, with contributions ranging from -31. 8% to 53. 2%. The QTLs in chromosome 2, 5 and 7 were found to have pleiotropy.%稻米RVA谱是评价稻米蒸煮与食用品质的重要指标之一,发掘新的控制稻米RVA谱QTL对稻米品质改良具有重要意义.利用以粳稻品种日本晴为受体、籼稻品种9311为供体并经高通量重测序的染色体片段代换系群体为材料,在两年两点的环境下对该群体中控制RVA谱特征值的QTL进行了定位分析.通过单因素方差分析和Dunnett多重比较,分析染色体片段代换系与受体亲本之间相关RVA谱特征值的差异,以两年两点都能检测到的显著差异位点作为稳定表达的QTL.共检测到10个稳定表达的QTL,包括控制峰值黏度的4个QTL qPKV2.1、qPKV5.1、qPKV7.1和qPKV8.1,控制热浆黏度的2个QTL qHPV5.1和qHPV7.1,

  6. Development and identification of wheat-Ag. pulcherrimum addition line and substitution line with BYDV resistance

    Institute of Scientific and Technical Information of China (English)

    武东亮; 辛志勇; 陈孝; 徐惠君; 马有志; 张增艳

    1999-01-01

    Breeding materials derived from CPI113500, amphidiploid of T. turgidum×Ag. pulcherrimum with barley yellow dwarf virus (BYDV) resistance, were evaluated by using BYDV resistance test, morphology observation, cytogenetics analysis, aneuploid analysis, isozyme electrophoresis, in situ hybridization. Two new germplasms resistant to BYDV were obtained. They were T. aestivum-Ag, pulcherrimum disomic addition line 96S16-11, and T. aestivum-Ag, pulcherrimum disomic substitution line 96W14-9.

  7. 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.

  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 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.

  10. 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.

  11. 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.

  12. Genetic divergence and the genetic architecture of complex traits in chromosome substitution strains of mice

    Directory of Open Access Journals (Sweden)

    Spiezio Sabrina H

    2012-05-01

    Full Text Available Abstract Background The genetic architecture of complex traits strongly influences the consequences of inherited mutations, genetic engineering, environmental and genetic perturbations, and natural and artificial selection. But because most studies are under-powered, the picture of complex traits is often incomplete. Chromosome substitution strains (CSSs are a unique paradigm for these genome surveys because they enable statistically independent, powerful tests for the phenotypic effects of each chromosome on a uniform inbred genetic background. A previous CSS survey in mice and rats revealed many complex trait genes (QTLs, large phenotypic effects, extensive epistasis, as well as systems properties such as strongly directional phenotypic changes and genetically-determined limits on the range of phenotypic variation. However, the unusually close genetic relation between the CSS progenitor strains in that study raised questions about the impact of genetic divergence: would greater divergence between progenitor strains, with the corresponding changes in gene regulation and protein function, lead to significantly more distinctive phenotypic features, or alternatively would epistasis and systems constraints, which are pervasive in CSSs, limit the range of phenotypic variation regardless of the extent of DNA sequence variation? Results We analyzed results for an extensive survey of traits in two new panels of CSSs where the donor strains were derived from inbred strains with more distant origins and discovered a strong similarity in genetic and systems properties among the three CSS panels, regardless of divergence time. Conclusion Our results argue that DNA sequence differences between host and donor strains did not substantially affect the architecture of complex traits, and suggest instead that strong epistasis buffered the phenotypic effects of genetic divergence, thereby constraining the range of phenotypic variation.

  13. Demarcation of informative chromosomes in tropical sweet corn inbred lines using microsatellite DNA markers

    Directory of Open Access Journals (Sweden)

    Pedram Kashiani

    2012-01-01

    Full Text Available A study of genetic variation among 10 pairs of chromosomes extracted from 13 tropical sweet corn inbred lines, using 99 microsatellite markers, revealed a wide range of genetic diversity. Allelic richness and the number of effective alleles per chromosome ranged from 2.78 to 4.33 and 1.96 to 3.47, respectively, with respective mean values of 3.62 and 2.73. According to the Shannon's information index (I and Nei's gene diversity coefficient (Nei, Chromosome 10 was the most informative chromosome (I = 1.311 and Nei = 0.703, while Chromosome 2 possessed the least (I = 0.762 and Nei = 0.456. Based on linkage disequilibrium (LD measurements for loci less than 50 cM apart on the same chromosome, all loci on Chromosomes 1, 6 and 7 were in equilibrium. Even so, there was a high proportion of genetic variation in Chromosomes 4, 5, 8, 9 and 10, thereby revealing their appropriateness for use in the genetic diversity investigations among tropical sweet corn lines. Chromosome 4, with the highest number of loci in linkage disequilibrium, was considered the best for marker-phenotype association and QTL mapping, followed by Chromosomes 5, 8, 9 and 10.

  14. A mouse chromosome 4 balancer ENU-mutagenesis screen isolates eleven lethal lines

    Science.gov (United States)

    ENU-mutagenesis is a powerful technique to identify genes regulating mammalian development. To functionally annotate the distal region of mouse chromosome 4, we performed an ENU-mutagenesis screen using a balancer chromosome targeted to this region of the genome. We isolated 11 lethal lines that map...

  15. 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.

  16. Induction of chromosome aberrations in two lines of cultured cells using different types of radiation

    International Nuclear Information System (INIS)

    The induction of chromosome aberrations has been investigated in two lines of cultured cells for different types of radiation. The obtained results are compared with information on induction of cell reproductive death and malignant transformation. (Auth.)

  17. 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.

  18. 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...

  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. Chromosomal imbalances in four new uterine cervix carcinoma derived cell lines

    Directory of Open Access Journals (Sweden)

    Vázquez Guelaguetza

    2003-03-01

    Full Text Available Abstract Background Uterine cervix carcinoma is the second most common female malignancy worldwide and a major health problem in Mexico, representing the primary cause of death among the Mexican female population. High risk human papillomavirus (HPV infection is considered to be the most important risk factor for the development of this tumor and cervical carcinoma derived cell lines are very useful models for the study of viral carcinogenesis. Comparative Genomic Hybridization (CGH experiments have detected a specific pattern of chromosomal imbalances during cervical cancer progression, indicating chromosomal regions that might contain genes that are important for cervical transformation. Methods We performed HPV detection and CGH analysis in order to initiate the genomic characterization of four recently established cervical carcinoma derived cell lines from Mexican patients. Results All the cell lines were HPV18 positive. The most prevalent imbalances in the cell lines were gains in chromosomes 1q23-q32, 3q11.2-q13.1, 3q22-q26.1, 5p15.1-p11.2, this alteration present as a high copy number amplification in three of the cell lines, 7p15-p13, 7q21, 7q31, 11q21, and 12q12, and losses in 2q35-qter, 4p16, 6q26-qter, 9q34 and 19q13.2-qter. Conclusions Analysis of our present findings and previously reported data suggest that gains at 1q31-q32 and 7p13-p14, as well as losses at 6q26-q27 are alterations that might be unique for HPV18 positive cases. These chromosomal regions, as well as regions with high copy number amplifications, coincide with known fragile sites and known HPV integration sites. The general pattern of chromosomal imbalances detected in the cells resembled that found in invasive cervical tumors, suggesting that the cells represent good models for the study of cervical carcinoma.

  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. Retroviral vector performance in defined chromosomal Loci of modular packaging cell lines.

    Science.gov (United States)

    Gama-Norton, L; Herrmann, S; Schucht, R; Coroadinha, A S; Löw, R; Alves, P M; Bartholomae, C C; Schmidt, M; Baum, C; Schambach, A; Hauser, H; Wirth, D

    2010-08-01

    The improvement of safety and titer of retroviral vectors produced in standard retroviral packaging cell lines is hampered because production relies on uncontrollable vector integration events. The influences of chromosomal surroundings make it difficult to dissect the performance of a specific vector from the chromosomal surroundings of the respective integration site. Taking advantage of a technology that relies on the use of packaging cell lines with predefined integration sites, we have systematically evaluated the performance of several retroviral vectors. In two previously established modular packaging cell lines (Flp293A and 293 FLEX) with single, defined chromosomal integration sites, retroviral vectors were integrated by means of Flp-mediated site-specific recombination. Vectors that are distinguished by different long terminal repeat promoters were introduced in either the sense or reverse orientation. The results show that the promoter, viral vector orientation, and integration site are the main determinants of the titer. Furthermore, we exploited the viral production systems to evaluate read-through activity. Read-through is thought to be caused by inefficient termination of vector transcription and is inherent to the nature of retroviral vectors. We assessed the frequency of transduction of sequences flanking the retroviral vectors from both integration sites. The approach presented here provides a platform for systematic design and evaluation of the efficiency and safety of retroviral vectors optimized for a given producer cell line. PMID:20222806

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

    International Nuclear Information System (INIS)

    The influence of yttrium (Y) substitution on ferromagnetic resonance (FMR), initial permeability, and magnetic properties of NiFe2O4 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 NiY0.12Fe1.88O4 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 Y3+ 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 NiY0.24Fe1.76O4 ferrites

  4. 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.

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

    Directory of Open Access Journals (Sweden)

    Yong-Wu Li

    2016-01-01

    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, 12p13.31-13.33, and 17p13.1-13.3. Moreover, at least four genes (MME, SI, BCHE, and KNG may be involved in the human lung adenocarcinoma cell line OM.

  6. Chromosomal Aberrations in DNA Repair Defective Cell Lines: Comparisons of Dose Rate and Radiation Quality

    Science.gov (United States)

    George, K. A.; Hada, M.; Patel, Z.; Huff, J.; Pluth, J. M.; Cucinotta, F. A.

    2009-01-01

    Chromosome aberration yields were assessed in DNA double-strand break repair (DSB) deficient cells after acute doses of gamma-rays or high-LET iron nuclei, or low dose-rate (0.018 Gy/hr) gamma-rays. We studied several cell lines including fibroblasts deficient in ATM (product of the gene that is mutated in ataxia telangiectasia patients) or NBS (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 radiation induced higher 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 chromosome exchange types were significantly higher for the ATM and NBS defective lines than for normal fibroblasts. However, the linear dose-response term was significantly higher only for simple exchanges in the NBS cells. Large increases in the quadratic dose response terms indicate the important roles of ATM and NBS in chromatin modifications that facilitate correct DSB repair and minimize aberration formation. Differences in the response of AT and NBS deficient cells at lower doses suggests important questions about the applicability of observations of radiation sensitivity at high dose to low dose exposures. For all iron nuclei irradiated cells, regression models preferred purely linear and quadratic dose responses for simple and complex exchanges, respectively. All the DNA repair defective cell lines had lower Relative biological effectiveness (RBE) values than normal cells, the lowest being for the DNA-PK-deficient cells, which was near unity. To further

  7. Chromosome substitution strain assessment of a Huntington’s disease modifier locus

    OpenAIRE

    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.

    2015-01-01

    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) HdhQ111 knock-in mice, replicates of the HD mutation, and the C57BL/6J-chr1...

  8. Revision of the chromosome anomalies of the T-cell malignant cell line peer.

    Science.gov (United States)

    Massaad, L; Venuat, A M; Remvikos, Y; Dutrillaux, B

    1990-01-01

    A high resolution chromosome banding method was applied to define the karyotype of the PEER cell line. It was found significantly different from that previously described, and can be characterized as follows: 46,XX,-4, del(5) (q21q23), del(6)(q14q22), del(9)(p12p21), i(9p), +der(4) rea(4) involving a large duplication of 4q. The cell cycle duration varies in relation to the time after splitting, slow from 0 to 48 h and faster from 48 to 96 h. The average time found was 25 h with durations of 6 and 15 h for G2 and S-phases, respectively. This variable cell cycle led us to change the conditions of BrdU incorporation to obtain a convenient R-banding. According to our own experience, this can be transposed to many other malignant cells to obtain a high resolution chromosome banding. PMID:2241089

  9. RBE of neutrons for induction of cell reproductive death and chromosome aberrations in three cell lines

    International Nuclear Information System (INIS)

    The authors have compared the RBE values for induction of dicentrics and centric rings with those for cell inactivation and with the mean or effective quality factors (Q) recommended for radiation protection. The induction of cell reproductive death and chromosome aberrations has been investigated in plateau phase cultures of established lines of a rat rhabdomyosarcoma, a rat ureter carcinoma and Chinese hamster cells for single doses of 300 kV X-rays and 0.5, 4.2 and 15 MeV neutrons. The different cell lines show considerable variations in sensitivity and the RBE values obtained are presented in tabular form. The mean RBE values for the rat rhabdomyosarcoma cells are lower than those for the other two relatively resistant cell lines. Those for the Chinese hamster cells extrapolated to levels according to low doses of X-rays are in good agreement with the quoted Q values. (Auth./C.F.)

  10. 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.

  11. From single nucleotide substitutions up to chromosomal deletions: genetic pause of leucism-associated disorders in animals.

    Science.gov (United States)

    Fleck, Katharina; Erhardt, Georg; Lühken, Gesine

    2016-01-01

    Leucism is characterized by a complete or partial white skin and hair in combination with pigmented irides, which can be vivid blue or heterochromatic. This is due to a complete or partial lack of melanocytes. The underlying pathogenesis is a disturbed emigration or differentiation of neural crest-derived cells. Therefore, leucistic phenotypes can be associated with defects, which mainly impair sensory organs and nerves. In humans, a well-known example is the Waardenburg syndrome. Leucism-associated disorders were also described in mouse, rat, hamster, rabbit, mink, cat, dog, pig, sheep, llama, alpaca, cattle and horse. In some of these species already identified causal mutations affect the genes EDN3, EDNRB, KIT, MITF, PAX3, SILV and SOX10. Defect alleles represent different types of genetic variation, ranging from single nucleotide substitutions up to larger chromosomal deletions. Some of the defect alleles produce desired coat color patterns. In some but not all cases, available genetic tests enable breeders to avoid production of animals affected by a leucism-associated disorder. PMID:27529988

  12. 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.

    2009-01-01

    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. PMID:19603076

  13. 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.

  14. Germ-line transmitted, chromosomally integrated HHV-6 and classical Hodgkin lymphoma.

    Directory of Open Access Journals (Sweden)

    Adam J Bell

    Full Text Available A unique feature of both human herpesvirus 6A and B (HHV-6A and B among human herpesviruses is their ability to integrate into chromosomal telomeres. In some individuals integrated viral genomes are present in the germ-line and result in the vertical transmission of HHV-6; however, little is known about the disease associations of germ-line transmitted, chromosomally integrated HHV-6 (ciHHV-6. Recent publications suggest that HHV-6 is associated with classical Hodgkin lymphoma (cHL. Here we examine the prevalence of ciHHV-6 in 936 cases of cHL and 563 controls by screening with a duplex TaqMan assay and confirming with droplet digital PCR. ciHHV-6 was detected in 10/563 (1.8% controls and in all but one individual the virus was HHV-6B. Amongst cases 16/936 (1.7% harboured ciHHV-6, thus demonstrating no association between ciHHV-6 and risk of cHL.

  15. Sunflower centromeres consist of a centromere-specific LINE and a chromosome-specific tandem repeat

    Science.gov (United States)

    Nagaki, Kiyotaka; Tanaka, Keisuke; Yamaji, Naoki; Kobayashi, Hisato; Murata, Minoru

    2015-01-01

    The kinetochore is a protein complex including kinetochore-specific proteins that plays a role in chromatid segregation during mitosis and meiosis. The complex associates with centromeric DNA sequences that are usually species-specific. In plant species, tandem repeats including satellite DNA sequences and retrotransposons have been reported as centromeric DNA sequences. In this study on sunflowers, a cDNA-encoding centromere-specific histone H3 (CENH3) was isolated from a cDNA pool from a seedling, and an antibody was raised against a peptide synthesized from the deduced cDNA. The antibody specifically recognized the sunflower CENH3 (HaCENH3) and showed centromeric signals by immunostaining and immunohistochemical staining analysis. The antibody was also applied in chromatin immunoprecipitation (ChIP)-Seq to isolate centromeric DNA sequences and two different types of repetitive DNA sequences were identified. One was a long interspersed nuclear element (LINE)-like sequence, which showed centromere-specific signals on almost all chromosomes in sunflowers. This is the first report of a centromeric LINE sequence, suggesting possible centromere targeting ability. Another type of identified repetitive DNA was a tandem repeat sequence with a 187-bp unit that was found only on a pair of chromosomes. The HaCENH3 content of the tandem repeats was estimated to be much higher than that of the LINE, which implies centromere evolution from LINE-based centromeres to more stable tandem-repeat-based centromeres. In addition, the epigenetic status of the sunflower centromeres was investigated by immunohistochemical staining and ChIP, and it was found that centromeres were heterochromatic. PMID:26583020

  16. 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.

  17. 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.

  18. Fluorescent In Situ Hybridization as a Genetic Technology to Analyzing Chromosomal Organization of Alien Wheat Recombinant Lines

    International Nuclear Information System (INIS)

    Fluorescent in situ hybridization is a valuable method for physical mapping of DNA sequence to chromosomes and genomes and to analyzing their organization, diversity, evolution and function. Using genomic DNA the origin of chromatin in hybrids and alien introgression lines can be identified and followed through breeding programmes. We have applied this technology to study the chromosome composition of new recombinants and genomes derived from spontaneous and induced translocations in particular involving rye and the goat grass Thinoyrum intermedium that transfer disease and stress resistance to wheat. We have established flow diagrammes for easy identification of the alien chromosome material. (author)

  19. Construction and characterization of a bacterial artificial chromosome library of the maize inbred line Qi319

    Directory of Open Access Journals (Sweden)

    Chun Hua Mu

    2016-03-01

    Full Text Available Zea mays L. has been the most cultivated crop and the crop with the largest yield in China since 2012. We constructed a bacterial artificial chromosome (BAC library for the maize inbred line Qi319, which may be used as a key source for disease-resistant maize breeding in China. The BAC contains 270,720 clones, with an average insert size of 90 kb. The coverage of the library is about 10.43 genome equivalents when considering a haploid genome size of 2300 Mb, providing a 99.99% likelihood of isolating any maize gene or sequence in the library. An average of 12 clones were obtained by polymerase chain reaction screening by using primer pairs linked to the genes for resistance to maize southern rust and rough dwarf. The results indicate that the library can satisfy the requirements for recovering specific sequences. The library is available to researchers to whom it may be of interest.

  20. [Effect of gametocidal chromosome 4S' on the phenotype segregation ratio in genetic analysis of common wheat lines].

    Science.gov (United States)

    Vdovichenko, Zh V; Antoniuk, M Z; Ternovskaia, T K

    2003-01-01

    Using experimental data on genetic analysis of introgressive lines for the character "hairy leaf sheath" controlled by the "cuckoo" chromosome 4S1, the algorithm for calculation of the theoretical segregation ratio in F2 was developed. Segregation distortion is caused by non-viability of the majority of gametes lacking the chromosome 4S1. The frequency of functioning gametes without the chromosome 4S1 is determined by the probability p versus the theoretically expected ratio 7 nonviable: 9 viable ones. Since segregation involves two characters, gamete viability and hairiness, the ratio 15 hairy: 1 hairless was used as a basis for search of the frequency p by maximum-likelihood method using 16 populations F2 from crossing the lines differing in the character studied. PMID:14650327

  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. 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.

  3. Analysis of SINE and LINE repeat content of Y chromosomes in the platypus, Ornithorhynchus anatinus.

    Science.gov (United States)

    Kortschak, R Daniel; Tsend-Ayush, Enkhjargal; Grützner, Frank

    2009-01-01

    Monotremes feature an extraordinary sex-chromosome system that consists of five X and five Y chromosomes in males. These sex chromosomes share homology with bird sex chromosomes but no homology with the therian X. The genome of a female platypus was recently completed, providing unique insights into sequence and gene content of autosomes and X chromosomes, but no Y-specific sequence has so far been analysed. Here we report the isolation, sequencing and analysis of approximately 700 kb of sequence of the non-recombining regions of Y2, Y3 and Y5, which revealed differences in base composition and repeat content between autosomes and sex chromosomes, and within the sex chromosomes themselves. This provides the first insights into repeat content of Y chromosomes in platypus, which overall show similar patterns of repeat composition to Y chromosomes in other species. Interestingly, we also observed differences between the various Y chromosomes, and in combination with timing and activity patterns we provide an approach that can be used to examine the evolutionary history of the platypus sex-chromosome chain. PMID:19874720

  4. Design, Synthesis and Evaluation of N13-Substituted Evodiamine Derivatives against Human Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Senchuan Song

    2013-12-01

    Full Text Available Attempting to improve the anticancer activity and solubility of evodiamine in simulated gastric fluid (SGF and simulated intestinal fluid (SIF solutions, thirty-eight N13-substituted evodiamine derivatives were designed, synthesized and tested for antitumor activities against six kinds of human cancer cell lines, namely prostate cancer (DU-145 and PC-3, lung cancer (H460, breast cancer (MCF-7, colon cancer (HCT-5 and glioblastoma (SF-268. The solubility of these compounds in SGF and SIF solutions was evaluated, and apoptosis induced by 2-2, 2-3, 2-16 and 3-2 was determined. The results showed: (1 among all compounds examined, 2-16 showed the highest antitumor activity and a broader spectrum of activity, with IC50 values ranging from 1–2 µM; (2 their solubility was obviously improved; (3 2-3, 2-16 and 3-2 had a significant impact inducing apoptosis in some cancer cell lines. The preliminary structure-activity relationships of these derivatives were discussed.

  5. 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. PMID:27245423

  6. 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

  7. Chromosomal mutations and chromosome loss measured in a new human-hamster hybrid cell line, ALC: studies with colcemid, ultraviolet irradiation, and 137Cs gamma-rays

    Science.gov (United States)

    Kraemer, S. M.; Waldren, C. A.; Chatterjee, A. (Principal Investigator)

    1997-01-01

    Small mutations, megabase deletions, and aneuploidy are involved in carcinogenesis and genetic defects, so it is important to be able to quantify these mutations and understand mechanisms of their creation. We have previously quantified a spectrum of mutations, including megabase deletions, in human chromosome 11, the sole human chromosome in a hamster-human hybrid cell line AL. S1- mutants have lost expression of a human cell surface antigen, S1, which is encoded by the M1C1 gene at 11p13 so that mutants can be detected via a complement-mediated cytotoxicity assay in which S1+ cells are killed and S1- cells survive. But loss of genes located on the tip of the short arm of 11 (11p15.5) is lethal to the AL hybrid, so that mutants that have lost the entire chromosome 11 die and escape detection. To circumvent this, we fused AL with Chinese hamster ovary (CHO) cells to produce a new hybrid, ALC, in which the requirement for maintaining 11p15.5 is relieved, allowing us to detect mutations events involving loss of 11p15.5. We evaluated the usefulness of this hybrid by conducting mutagenesis studies with colcemid, 137Cs gamma-radiation and UV 254 nm light. Colcemid induced 1000 more S1- mutants per unit dose in ALC than in AL; the increase for UV 254 nm light was only two-fold; and the increase for 137Cs gamma-rays was 12-fold. The increase in S1- mutant fraction in ALC cells treated with colcemid and 137Cs gamma-rays were largely due to chromosome loss and 11p deletions often containing a breakpoint within the centromeric region.

  8. 49 CFR 1242.76 - Administration; pickup and delivery, marine line haul, and rail substitute service; loading...

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Administration; pickup and delivery, marine line haul, and rail substitute service; loading, unloading and local marine; protective services; freight lost or damaged-solely related; fringe benefits; casualties and insurance; joint facility, and...

  9. 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.

  10. Sequence analysis of the MYC oncogene involved in the t(8;14)(q24;q11) chromosome translocation in a human leukemia T-cell line indicates that putative regulatory regions are not altered

    International Nuclear Information System (INIS)

    The authors cloned the translocation-associated and homologous normal MYC alleles from SKW-3, a leukemia T-cell line with the t(8; 14)(q24; q11) translocation, and determined the sequence of the MYC oncogene first exon and flanking 5' putative regulatory regions. S1 nuclease protection experiments utilizing a MYC first exon probe demonstrated transcriptional deregulation of the MYC gene associated with the T-cell receptor α locus on the 8q + chromosome of SKW-3 cells. Nucleotide sequence analysis of the translocation-associated (8q +) MYC allele identified a single base substitution within the upstream flanking region; the homologous nontranslocated allele contained an additional substitution and a two-base deletion. None of the deletions or substitutions localized to putative 5' regulatory regions. The MYC first exon sequence was germ line in both alleles. These results demonstrate that alterations within the putative 5' MYC regulatory regions are not necessarily involved in MYC deregulation in T-cell leukemias, and they show that juxtaposition of the T-cell receptor α locus to a germ-line MYC oncogene results in MYC deregulation

  11. Murine erythroleukemia cell line GM979 contains factors that can activate silent chromosomal human γ-globin genes

    International Nuclear Information System (INIS)

    The authors introduced a normal chromosome 11 into GM979 murine erythroleukemia cells by fusing them with Epstein-Barr virus-transformed lymphocytes from a normal individual. In contrast to precious data obtained with other murine erythroleukemia cells, they detected activation of human chromosomal γ-globin genes in GM979 cells. GM979, unlike previously used murine erythroleukemia cell lines, expresses murine embryonic globin in addition to adult globin. While all the hybrids expressed γ- and β-globin, they displayed a wide range of γ-globin expression in relation to that of β-globin. No correlation, however, was found in quantitative expression between murine embryonic globin and human γ-globin in these hybrids, suggesting that the two globins are regulated independently, at least in this cell line. These data indicate that γ-globin genes from normal, nonerythroid chromosomes are not irreversibly silenced, and they can be activated by a positive trans factor(s) present in GM979 cells

  12. IAPT/IOPB chromosome data 20 (extende on-line version)

    Czech Academy of Sciences Publication Activity Database

    Altinordu, F.; Šumberová, Kateřina; Ankova, T.; Erst, A. S.; Kuzmin, I. V.; Shaulo, D. N.; Plugatar, Y. V.; Baltisberger, M.; Deldago, L.; Gallego Martín, F.; Rico, E.; Lavia, G. I.; Krapovickas, A.; de los Angeles Martines, M.; Lazaroff, Y.; Solis Neffa, V. G.; Ortiz, A. M.; Sivestri, M. C.; Pavlova, D.; Bani, A.; Polido, C. A.; Moraes, A. P.; Forni-Martins, E. R.; Probatova, N. S.; Kazanovsky, S. G.; Barkalov, V. Y.; Rudyka, E. G.; Shatokhina, A. V.; Krivenko, D. A.; Verkhozina, A. V.; Nechaev, V. A.; Romero-da Cruz, M. V.; Wefferling, K. M.; Owen, H. A.; Hoot, S. B.

    2015-01-01

    Roč. 64, č. 6 (2015), E1-E39. ISSN 0040-0262 R&D Projects: GA ČR GB14-36079G Institutional support: RVO:67985939 Keywords : chromosome count * angiosperms * DNA -Sequences Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.299, year: 2014

  13. Seedling tolerance to Rhizoctonia and Pythium in wheat chromosome group 4 addition lines from Thinopyrum spp

    Science.gov (United States)

    Chromosome 4 from Thinopyrum spp. confers regrowth after a sexual cycle and senescence in hexaploid wheat (Triticum aestivum), and is associated with resistance to the necrotrophic eyespot pathogen, Tapesia yallundae. We sought to determine whether robust root growth or other traits expressed in ch...

  14. 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.

  15. A recurrent chromosome translocation breakpoint in breast and pancreatic cancer cell lines targets the neuregulin/NRG1 gene.

    Science.gov (United States)

    Adélaïde, José; Huang, Huai-En; Murati, Anne; Alsop, Amber E; Orsetti, Béatrice; Mozziconacci, Marie-Joëlle; Popovici, Cornel; Ginestier, Christophe; Letessier, Anne; Basset, Céline; Courtay-Cahen, Céline; Jacquemier, Jocelyne; Theillet, Charles; Birnbaum, Daniel; Edwards, Paul A W; Chaffanet, Max

    2003-08-01

    The 8p11-21 region is a frequent target of alterations in breast cancer and other carcinomas. We surveyed 34 breast tumor cell lines and 9 pancreatic cancer cell lines for alterations of this region by use of multicolor fluorescence in situ hybridization (M-FISH) and BAC-specific FISH. We describe a recurrent chromosome translocation breakpoint that targets the NRG1 gene on 8p12. NRG1 encodes growth factors of the neuregulin/heregulin-1 family that are ligands for tyrosine kinase receptors of the ERBB family. Breakpoints within the NRG1 gene were found in four of the breast tumor cell lines: ZR-75-1, in a dic(8;11); HCC1937, in a t(8;10)(p12;p12.1); SUM-52, in an hsr(8)(p12); UACC-812, in a t(3;8); and in two of the pancreatic cancer cell lines: PaTu I, in a der(8)t(4;8); and SUIT-2, in a del(8)(p). Mapping by two-color FISH showed that the breaks were scattered over 1.1 Mb within the NRG1 gene. It is already known that the MDA-MB-175 breast tumor cell line has a dic(8;11), with a breakpoint in NRG1 that fuses NRG1 to the DOC4 gene on 11q13. Thus, we have found a total of seven breakpoints, in two types of cancer cell lines, that target the NRG1 gene. This suggests that the NRG1 locus is a recurring target of translocations in carcinomas. PCR analysis of reverse-transcribed cell line RNAs revealed an extensive complexity of the NRG1 transcripts but failed to detect a consistent pattern of mRNA isoforms in the cell lines with NRG1 breakpoint. PMID:12800145

  16. 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.

  17. Temperature-dependent dielectric properties and line profile analysis of zinc-substituted copper ferrites

    Science.gov (United States)

    Lamani, A. R.; Jayanna, H. S.; Naveen, C. S.; Rajeeva, M. P.; Prasanna, G. D.; Chaturmukha, V. S.; Harish, B. M.; Suresh, S.; Avinash, B. S.

    2016-05-01

    Temperature dependence of dielectric constant and loss has been investigated for different compositions of Zinc substituted copper ferrites with general formula Cu1-xZnxFe2O4 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) prepared by ceramic method. XRD analysis confirms all the samples exhibit single phase cubic spinel structure. The dielectric constant and loss of the sample were studied in the temperature ranges from RT to 1000K at different constant frequency. Samples of the composition with x = 0.8 show low dielectric loss up to a measured temperature around 770 °C at higher frequencies as compared to samples of other compositions. A plot of dielectric constant versus temperature shows a transition near the Curie temperature, an attempt is made to explain the possible mechanism for this observation. The dielectric constant increases slowly from 309°C to 770°C with temperature in the beginning and sharply decreases with increase in frequency for all the samples. The variation of tanδ with frequency shows cusps for all the samples except for x = 0.6. These variations have been explained on the basis of Koop's phenomenological theory. The variation of dielectric loss tangent with frequency showed maxima for the 1 KHz. These maxima are also found to shift towards low-frequency region as the content of Zn increases.

  18. 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.

  19. Divergence of the genes on human chromosome 21 between human and other hominoids and variation of substitution rates among transcription units

    OpenAIRE

    Shi, Jinxiu; Xi, Huifeng; Zhang, Chenghui; Jiang, Zhengwen; Zhang, Kuixing; Shen, Yayun; Jin, Lin; Zhang, Kaiyue; Yuan, Wentao; Ying WANG; Lin, Jie; Hua, Qi; Wang, Fengqing; Xu, Shuhua; Ren, Suangxi

    2003-01-01

    The study of genomic divergence between humans and primates may provide insight into the origins of human beings and the genetic basis of unique human traits and diseases. Chromosome 21 is the smallest chromosome in the human genome, and some of its regions have been implicated in mental retardation and other diseases. In this study, we sequenced the coding and regulatory regions of 127 known genes on human chromosome 21 in DNA samples from human and chimpanzees and a ...

  20. Reciprocal chromosome translocation associated with TDNA-insertion mutation in Arabidopsis: genetic and cytological analyses of consequences for gametophyte development and for construction of doubly mutant lines

    OpenAIRE

    Curtis, Marc J.; Belcram, Katia; Stephanie R Bollmann; Tominey, Colin M.; Hoffman, Peter D.; Mercier, Raphael; Hays, John B.

    2008-01-01

    Chromosomal rearrangements may complicate construction of Arabidopsis with multiple TDNA-insertion mutations. Here, crossing two lines homozygous for insertions in AtREV3 and AtPOLH (chromosomes I and V, respectively) and selfing F1 plants yielded non-Mendelian F2 genotype distributions: frequencies of +/++/+ and 1/1 2/2 progeny were only 0.42 and 0.25%. However, the normal development and fertility of double mutants showed AtPOLH-1 and AtREV3-2 gametes and 1/1 2/2 embryos to be fully viable....

  1. Analysis of a valuable chromosome rearrangement induced by ionizing radiations in a cultivated chili pepper line (Capsicum baccatum var. Pendulum - solanaceae)

    International Nuclear Information System (INIS)

    Capsicum (chili peppers) is an important genus including five crop species consumed by man as spice and food. Most contributions about induced mutagenesis in Capsicum refer to gene mutations while induced changes at chromosome level are scarce. We started a program to achieve chromosome rearrangements by ionizing radiations in C. baccatum variety pendulum cultivar 'cayenne', which has a karyotype with 2n=2x=24, 11 metacentrics + 1 subtelocentric pairs, 4 pairs (1, 3, 10, 12) carrying nucleolar organizing regions (NORs) and associated satellites in short arm. Seeds were treated with different acute doses of X-rays developing M1-4 generations. A rearranged chromosome carrying NORs in both arms was found in M2 seedlings from the only surviving M1 plant after a 300 Gy treatment. The structural change was analyzed by: 1) Feulgen's staining to observe chromosome number, size and shape; 2) silver impregnation to detect active NORs; 3) fluorescent chromosome banding to reveal type and position of constitutive heterochromatic regions [triple staining with chromomycin/distamycin/4-6-diamidino-2-phenylindole (CMA/DA/DAPI)]; 4) fluorescent in situ hybridization with 18S- 25S rDNA repeated sequence as probe. A reciprocal translocation between two NOR-bearing chromosomes in the M1 plant has occurred, which gave viable progeny carrying the chromosomal interchange without any deviating phenotype after four generations, nor in heterozygous neither in homozygous condition. The lack of chromosome instability suggests a small reciprocal interchange between a member of pair 1 and of 3, both carrying active NORs in shorts arms. The results of this rearrangement were two chromosomes with little change in size, one of them easily recognized by the presence of NORs and associated CMA+/DAPI- heterochromatin in both arms. As the translocation here reported produced a conspicuous rearranged marker chromosome, the obtained plant line is considered very valuable for studies on chromosome

  2. Stable persistence of the yeast plasmid by hitchhiking on chromosomes during vegetative and germ-line divisions of host cells

    OpenAIRE

    Sau, Soumitra; Liu, Yen-Ting; Ma, Chien-Hui; Jayaram, Makkuni

    2015-01-01

    The chromosome-like stability of the Saccharomyces cerevisiae plasmid 2 micron circle likely stems from its ability to tether to chromosomes and segregate by a hitchhiking mechanism. The plasmid partitioning system, responsible for chromosome-coupled segregation, is comprised of 2 plasmid coded proteins Rep1 and Rep2 and a partitioning locus STB. The evidence for the hitchhiking model for mitotic plasmid segregation, although compelling, is almost entirely circumstantial. Direct tests for pla...

  3. 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

  4. Gene targeting of X chromosome-linked chronic granulomatous disease locus in a human myeloid leukemia cell line and rescue by expression of recombinant gp91phox.

    OpenAIRE

    Zhen, L.; KING, A.A.; Xiao, Y.; Chanock, S. J.; Orkin, S H; Dinauer, M.C.

    1993-01-01

    The X chromosome-linked chronic granulomatous disease (X-CGD) locus, which encodes the gp91phox subunit of the phagocyte respiratory-burst oxidase cytochrome b, was disrupted by homologous recombination in the PLB-985 human myeloid cell line to develop an in vitro model of X-CGD. Superoxide formation was absent in targeted cells after differentiation to granulocytes but was rescued by stable transfection and expression of wild-type gp91phox cDNA. The targeted cell line should be useful in exp...

  5. Adoption of new HIV treatment guidelines and drug substitutions within first-line as a measure of quality of care in rural Lesotho: health centers and hospitals compared

    OpenAIRE

    Labhardt, N.D.; Sello, M.; Lejone, T.; J. Ehmer; Mokhantso, M.; Lynen, L; K. Pfeiffer

    2012-01-01

    Objective: In 2007, Lesotho launched new national antiretroviral treatment (ART) guidelines, prioritising tenofovir and zidovudine over stavudine as a backbone together with lamivudine. We compared the rate of adoption of these new guidelines and substitution of first-line drugs by health centers (HC) and hospitals in two catchment areas in rural Lesotho. Methods: Retrospective cohort analysis. Patients aged >/=16 years were stratified into a HC- and a hospital-group. Main outcome variables:...

  6. Clonal evolution and tumor progression in 2 human colorectal adenoma-derived cell-lines invitro - the involvement of chromosome-1 abnormalities.

    Science.gov (United States)

    Hague, A; Hanlon, K; Paraskeva, C

    1992-07-01

    Two human colorectal adenoma cell lines, S/RG and S/AN, have been continuously passaged in vitro to determine whether they would immortalize and if specific cytogenetic changes were involved in immortalization and tumor progression. At passage 7, S/RG was highly aneuploid, but had no abnormalities of chromosome 1 (Paraskeva et al, Cancer Res 49: 1282-1286, 1989). With continued passage under two independent sets of growth conditions an isochromosome Iq and derivatives of this isochromosome occurred as specific abnormalities. S/AN was near-diploid at passage 10, with a deletion in lp and monosomy 18. The karyotype at passage 44 showed no change. The cell lines are stable in that they have remained anchorage-dependent and non-tumorigenic after several years in culture and S/AN has retained a near diploid karyotype. These cell lines are therefore highly valuable for further studies of tumor progression in human colorectal carcinogenesis. PMID:21584532

  7. Engineering the line up of electronic energy levels at inorganic-organic semiconductor interfaces by variation of surface termination and by substitution

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Thomas; Hunger, Ralf; Klein, Andreas; Jaegermann, Wolfram [University of Technology Darmstadt, Materials Science Institute, Surface Science Division, Petersenstrasse 23, 64287 Darmstadt (Germany)

    2008-09-15

    In the Anderson model the alignment of electronic energy levels follows from the assumption that the vacuum-levels of the contacting phases are at equal height. Engineering of the line up may be attempted by changing the ionization energy of the substrate and/or of the adsorbate. We report on the variation of the Si(111) ionization energy by induced surface dipoles of -CH{sub 3}, -H, and -GaSe terminations and the induced variation of the HOMO line up of PTCDA and ZnPc layers. In addition the variation of the line up by changing the organic molecule ionization energy is exemplified by F substitution in ZnPc. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. Introgression of chromosome 3Ns from Psathyrostachys huashanica into wheat specifying resistance to stripe rust.

    Science.gov (United States)

    Kang, Houyang; Wang, Yi; Fedak, George; Cao, Wenguang; Zhang, Haiqin; Fan, Xing; Sha, Lina; Xu, Lili; Zheng, Youliang; Zhou, Yonghong

    2011-01-01

    Wheat stripe rust is a destructive disease in the cool and humid wheat-growing areas of the world. Finding diverse sources of stripe rust resistance is critical for increasing genetic diversity of resistance for wheat breeding programs. Stripe rust resistance was identified in the alien species Psathyrostachys huashanica, and a wheat-P. huashanica amphiploid line (PHW-SA) with stripe rust resistance was reported previously. In this study, a P. huashanica 3Ns monosomic addition line (PW11) with superior resistance to stripe rust was developed, which was derived from the cross between PHW-SA and wheat J-11. We evaluated the alien introgressions PW11-2, PW11-5 and PW11-8 which were derived from line PW11 for reaction to new Pst race CYR32, and used molecular and cytogenetic tools to characterize these lines. The introgressions were remarkably resistant to CYR32, suggesting that the resistance to stripe rust of the introgressions thus was controlled by gene(s) located on P. huashanica chromosome 3Ns. All derived lines were cytologically stable in term of meiotic chromosome behavior. Two 3Ns chromosomes of P. huashanica were detected in the disomic addition line PW11-2. Chromosomes 1B of substitution line PW11-5 had been replaced by a pair of P. huashanica 3Ns chromosomes. In PW11-8, a small terminal segment from P. huashanica chromosome arm 3NsS was translocated to the terminal region of wheat chromosomes 3BL. Thus, this translocated chromosome is designated T3BL-3NsS. These conclusions were further confirmed by SSR analyses. Two 3Ns-specific markers Xgwm181 and Xgwm161 will be useful to rapidly identify and trace the translocated fragments. These introgressions, which had significant characteristics of resistance to stripe rust, could be utilized as novel germplasms for wheat breeding. PMID:21760909

  9. The chromosome content and genotype of two wheat cell lines and of their somatic fusion product with oat

    OpenAIRE

    Xiang, Fengning; Wang, Junfeng; Xu, Chunhui; Xia, Guangmin

    2010-01-01

    Somatic hybridization seeks to genetically combine phylogenetically distant parents. An effective system has been established in bread wheat (Triticum aestivum L.) involving protoplasts from a non-totipotent cell line adapted to in vitro culture (T1) in combination with totipotent protoplasts harvested from embryogenic calli (T2). Here, we report the karyotype and genotype of T1 and T2. Line T1 carries nine A (A-genome of wheat), seven B (B-genome of wheat) and eight D (D-genome of wheat) gen...

  10. 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...

  11. Cytological and Molecular Characterization of Homoeologous Group-1 Chromosomes in Hybrid Derivatives of a Durum Disomic Alien Addition Line

    Science.gov (United States)

    Fusarium head blight (FHB) is a devastating disease of durum wheat (Triticum turgidum L., 2n = 4x = 28; AABB). To incorporate FHB resistance from diploid wheatgrass (Lophopyrum elongatum (Host) Á. Löve, 2n = 2x = 14; EE) we produced earlier a stable alien disomic addition line, DGE-1, incorporating...

  12. 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.

  13. Chromosomal translocation in a human leukemic stem-cell line disrupts the T-cell antigen receptor δ-chain diversity region and results in a previously unreported fusion transcript

    International Nuclear Information System (INIS)

    The authors have studied a leukemic stem-cell line, DU.528, that is able to differentiate into myeloid and lymphoid cells. The leukemic cells have a translocation between chromosomes 1 and 14, t(1;14)(p33;q11), which they have molecularly cloned and sequenced. Initial screening used joining (J)-segment probes from the T-cell receptor (TCR) α- and δ-chain loci. In apparent concert with the translocation, a deletion has occurred between δ-chain diversity (D)-region genes Dδ1 and Dδ2. The nature of the Dδ1-Dδ2 deletional event implicates a lymphoid recombinase in the mechanism of the translocation. As a consequence of the translocation, an unusual fusion transcript was generated. Probes from chromosome 1 detected a previously unreported transcript in RNA from both the cell line and the patient. A chromosome 14 probe identified the same transcript, thus confirming a fusion transcript derived from both chromosomes 1 and 14. This translocation may identify a gene for which they propose the name SCL (stem-cell leukemia) that is important for hemopoietic development and oncogenesis and that has been disrupted or altered in this stem-cell line

  14. Temporal genomic evolution of bird sex chromosomes

    DEFF Research Database (Denmark)

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

    2014-01-01

    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...... evolved very recently. CONCLUSIONS: In conclusion, we uncover that the sequence and expression patterns of Z chromosome genes covary with their ages of becoming Z-linked. In contrast to the mammalian X chromosomes, such patterns are mainly driven by mutational bias and genetic drift in birds, due...... to the opposite sex-biased inheritance of Z vs. X....

  15. Exploring the tertiary gene pool of bread wheat: sequence assembly and analysis of chromosome 5M(g) of Aegilops geniculata.

    Science.gov (United States)

    Tiwari, Vijay K; Wang, Shichen; Danilova, Tatiana; Koo, Dal Hoe; Vrána, Jan; Kubaláková, Marie; Hribova, Eva; Rawat, Nidhi; Kalia, Bhanu; Singh, Narinder; Friebe, Bernd; Doležel, Jaroslav; Akhunov, Eduard; Poland, Jesse; Sabir, Jamal S M; Gill, Bikram S

    2015-11-01

    Next-generation sequencing (NGS) provides a powerful tool for the discovery of important genes and alleles in crop plants and their wild relatives. Despite great advances in NGS technologies, whole-genome shotgun sequencing is cost-prohibitive for species with complex genomes. An attractive option is to reduce genome complexity to a single chromosome prior to sequencing. This work describes a strategy for studying the genomes of distant wild relatives of wheat by isolating single chromosomes from addition or substitution lines, followed by chromosome sorting using flow cytometry and sequencing of chromosomal DNA by NGS technology. We flow-sorted chromosome 5M(g) from a wheat/Aegilops geniculata disomic substitution line [DS5M(g) (5D)] and sequenced it using an Illumina HiSeq 2000 system at approximately 50 × coverage. Paired-end sequences were assembled and used for structural and functional annotation. A total of 4236 genes were annotated on 5M(g) , in close agreement with the predicted number of genes on wheat chromosome 5D (4286). Single-gene FISH indicated no major chromosomal rearrangements between chromosomes 5M(g) and 5D. Comparing chromosome 5M(g) with model grass genomes identified synteny blocks in Brachypodium distachyon, rice (Oryza sativa), sorghum (Sorghum bicolor) and barley (Hordeum vulgare). Chromosome 5M(g) -specific SNPs and cytogenetic probe-based resources were developed and validated. Deletion bin-mapped and ordered 5M(g) SNP markers will be useful to track 5M-specific introgressions and translocations. This study provides a detailed sequence-based analysis of the composition of a chromosome from a distant wild relative of bread wheat, and opens up opportunities to develop genomic resources for wild germplasm to facilitate crop improvement. PMID:26408103

  16. LINES

    Directory of Open Access Journals (Sweden)

    Minas Bakalchev

    2015-10-01

    Full Text Available The perception of elements in a system often creates their interdependence, interconditionality, and suppression. The lines from a basic geometrical element have become the model of a reductive world based on isolation according to certain criteria such as function, structure, and social organization. Their traces are experienced in the contemporary world as fragments or ruins of a system of domination of an assumed hierarchical unity. How can one release oneself from such dependence or determinism? How can the lines become less “systematic” and forms more autonomous, and less reductive? How is a form released from modernistic determinism on the new controversial ground? How can these elements or forms of representation become forms of action in the present complex world? In this paper, the meaning of lines through the ideas of Le Corbusier, Leonidov, Picasso, and Hitchcock is presented. Spatial research was made through a series of examples arising from the projects of the architectural studio “Residential Transformations”, which was a backbone for mapping the possibilities ranging from playfulness to exactness, as tactics of transformation in the different contexts of the contemporary world.

  17. 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.

  18. Chromosomal aberration

    International Nuclear Information System (INIS)

    Chromosomal aberrations are classified into two types, chromosome-type and chromatid-type. Chromosom-type aberrations include terminal deletion, dicentric, ring and interstitial deletion, and chromatid-type aberrations include achromatic lesion, chromatid deletion, isochromatid deletion and chromatid exchange. Clastogens which induce chromosomal aberration are divided into ''S-dependent'' agents and ''S-independent''. It might mean whether they can induce double strand breaks independent of the S phase or not. Double strand breaks may be the ultimate lesions to induce chromosomal aberrations. Caffeine added even in the G2 phase appeared to modify the frequency of chromatid aberrations induced by X-rays and mitomycin C. Those might suggest that the G2 phase involves in the chromatid aberration formation. The double strand breaks might be repaired by ''G2 repair system'', the error of which might yield breakage types of chromatid aberrations and the by-pass of which might yield chromatid exchanges. Chromosome-type aberrations might be formed in the G1 phase. (author)

  19. 普通小麦-簇毛麦易位系T6BS·6BL-2VS的选育%Identification of Triticum aestivum-Haynaldia villosa Translocation Line T6BS·6BL-2VS

    Institute of Scientific and Technical Information of China (English)

    陈全战; 张边江; 周峰; 吴梅; 李华春

    2008-01-01

    [Objective] The aim of experiment was to provide a new germplasm for wheat breeding by further using desirable genes in 2V chromosome of Haynaldia villosa.[Method] Through hybridization between common wheat(Triticum aestivum)-Haynaldia villosa disomic substitution line and common wheat Nonglin26-3C chromosome of Aegilops triuncialis disomic addition line, the analysis methods such as chromosome C-banding, genomic in situ hybridization and molecular marker technique were comprehensively applied and combined characters investigation.[Result] The wheat-Haynaldia villosa translocation line(T6BS·6BL-2VS) was selected from hybrid progenies to conduct characters investigation,which found some bristles on glume ridge of T6BS·6BL-2VS.[Conclusion] The translocation line induced by gametocidal chromosome was a small segment translocation line and the gene of bristle on glume ridge of Haynaldia villosa was located between the middle and the terminal of 2VS.

  20. Evaluating the Y chromosomal timescale in human demographic and lineage dating

    OpenAIRE

    Wang, Chuan-Chao; Gilbert, M. Thomas P.; Jin, Li; Li, Hui

    2014-01-01

    Y chromosome is a superb tool for inferring human evolution and recent demographic history from a paternal perspective. However, Y chromosomal substitution rates obtained using different modes of calibration vary considerably, and have produced disparate reconstructions of human history. Here, we discuss how substitution rate and date estimates are affected by the choice of different calibration points. We argue that most Y chromosomal substitution rates calculated to date have shortcomings, ...

  1. Cell‐free DNA testing in a trisomy 21 pregnancy with confined placental mosaicism for a cell line with trisomy for both chromosomes 18 and 21

    OpenAIRE

    Crooks, Kristy; Edwardsen, Ginger; O'Connor, Siobhan; Powell, Cynthia; Vargo, Diane; Vora, Neeta; Kaiser‐Rogers, Kathleen

    2015-01-01

    Key Clinical Message NIPT (noninvasive prenatal testing) detected trisomy for two chromosomes. One trisomy reflected the fetal karyotype, and the other resulted from CPM (confined placental mosaicism). This case illustrates that extensive cytogenetic analysis can be required to identify CPM, and that patients should be counseled regarding the possibility of discordant NIPT results.

  2. 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.

  3. 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. PMID:26111960

  4. 小麦-黑麦代换系间、代换系与易位系间杂交后代染色体易位系的选育%Selection of Wheat-rye Chromosome Translocation Lines between Substitution Lines or between Substitution Lines and Translocation Lines

    Institute of Scientific and Technical Information of China (English)

    张延明; 李宇欣; 李集临; 王晓萍

    2010-01-01

    为了选育有经济价值的易位系,探讨小麦-黑麦间产生易位的频率,本研究以小麦-黑麦代换系DS5R/5A和DS6R/6A为母本,以小麦-黑麦易位系克珍(Kezhen)和带有杀配子染色体的代换系DSGC1为父本,分别进行田间杂交.结果表明:DS5R/5A、DS6R/6A与DSGC1(2S)杂交结实率低,平均为27.7%,与克珍(T3B.3R)杂交结实率高于前者,平均结实率为59.3%,二者均好于远缘杂交的结实率,这也表明带有杀配子染色体的亲本影响结实率;对选出的54株DS5R/5A×DSGC1、DS6R/6A×DSGC1杂种后代与80株DS5R/5Ax克珍、DS6R/6Ax克珍杂种后代进行C-分带、原位杂交和分子标记鉴定后发现,二者的易位频率分别为11.1%和8.8%,并且多为染色体端部小片段易位,这种小片段易位可能是代换系间杂交部分同源染色体交换产生的.此外,也表明杀配子染色体在引起染色体断裂后可发生染色体易位.本研究共获得T5RL.5AS、T5RS.5DL、T5RS.5BL、T6RL.6DS、6RL.6BS以及T6RS.6BL等13个易位系,平均易位频率为9.6%.

  5. Isolation and chromosomal distribution of a novel Ty1-copia-like sequence from Secale, which enables identification of wheat-Secale africanum introgression lines.

    Science.gov (United States)

    Jia, J; Yang, Z; Li, G; Liu, Ch; Lei, M; Zhang, T; Zhou, J; Ren, Z

    2009-01-01

    A repetitive sequence of 411 bp, named pSaO5411, was identified in the Secale africanum genome (Ra) by random amplified polymorphic DNA (RAPD) analysis of wheat and wheat-S. africanum amphiploids. GenBank BLAST search revealed that the sequence of pSaO5411 was highly homologous to a part of a Ty1-copia retrotransposon. Fluorescence in situ hybridization (FISH) analyses indicated that pSaO5411 was significantly hybridized to S. africanum chromosomes of a wheat-S. africanum amphiploid, and it was dispersed along the Secale chromosome arms except the terminal regions. Basing on the sequence of pSaO5411, a pair of sequence-characterized amplified region (SCAR) primers were designed, and the resultant SCAR marker was able to target both cultivated rye and the wild Secale species, which also enabled to identify effectively the S. africanum chromatin introduced into the wheat genome. PMID:19193979

  6. Cloning of allene oxide cyclase gene from Leymus mollis and analysis of its expression in wheat–Leymus chromosome addition lines

    OpenAIRE

    Eltayeb Habora, Mohamed Elsadig; Eltayeb, Amin Elsadig; Oka, Mariko; Tsujimoto, Hisashi; TANAKA, Kiyoshi

    2013-01-01

    Leymus mollis (Triticeae; Poaceae) is a useful genetic resource for wheat (Triticum aestivum L.) breeding via wide hybridization to introduce its chromosomes and integrate its useful traits into wheat. Leymus mollis is highly tolerant to abiotic stresses such as drought and salinity and resistant to various diseases, but the genetic mechanisms controlling its physiological tolerance remain largely unexplored. We identified and cloned an allene oxide cyclase (AOC) gene from L. mollis that was ...

  7. Dissection and cytological mapping of barley chromosome 2H in the genetic background of common wheat

    OpenAIRE

    Joshi, Giri Prasad; Nasuda, Shuhei; Endo, Takashi R.

    2011-01-01

    We used gametocidal (Gc) chromosomes 2C and 3C[SAT] to dissect barley 2H added to common wheat. The Gc chromosome induces chromosomal breakage resulting in chromosomal aberrations in the progeny of the 2H addition line of common wheat carrying the monosomic Gc chromosome. We conducted in situ hybridization to select plants carrying structurally rearranged aberrant 2H chromosomes and characterized them by sequential C-banding and in situ hybridization. We established 66 dissection lines of com...

  8. 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.

  9. Solvent substitution

    International Nuclear Information System (INIS)

    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

  10. Chromosome Microarray.

    Science.gov (United States)

    Anderson, Sharon

    2016-01-01

    Over the last half century, knowledge about genetics, genetic testing, and its complexity has flourished. Completion of the Human Genome Project provided a foundation upon which the accuracy of genetics, genomics, and integration of bioinformatics knowledge and testing has grown exponentially. What is lagging, however, are efforts to reach and engage nurses about this rapidly changing field. The purpose of this article is to familiarize nurses with several frequently ordered genetic tests including chromosomes and fluorescence in situ hybridization followed by a comprehensive review of chromosome microarray. It shares the complexity of microarray including how testing is performed and results analyzed. A case report demonstrates how this technology is applied in clinical practice and reveals benefits and limitations of this scientific and bioinformatics genetic technology. Clinical implications for maternal-child nurses across practice levels are discussed. PMID:27276104

  11. Identification of a Rice stripe necrosis virus resistance locus and yield component QTLs using Oryza sativa × O. glaberrima introgression lines

    Directory of Open Access Journals (Sweden)

    Prado Gustavo

    2010-01-01

    Full Text Available Abstract Background Developing new population types based on interspecific introgressions has been suggested by several authors to facilitate the discovery of novel allelic sources for traits of agronomic importance. Chromosome segment substitution lines from interspecific crosses represent a powerful and useful genetic resource for QTL detection and breeding programs. Results We built a set of 64 chromosome segment substitution lines carrying contiguous chromosomal segments of African rice Oryza glaberrima MG12 (acc. IRGC103544 in the genetic background of Oryza sativa ssp. tropical japonica (cv. Caiapó. Well-distributed simple-sequence repeats markers were used to characterize the introgression events. Average size of the substituted chromosomal segments in the substitution lines was about 10 cM and covered the whole donor genome, except for small regions on chromosome 2 and 4. Proportions of recurrent and donor genome in the substitution lines were 87.59% and 7.64%, respectively. The remaining 4.78% corresponded to heterozygotes and missing data. Strong segregation distortion was found on chromosomes 3 and 6, indicating the presence of interspecific sterility genes. To illustrate the advantages and the power of quantitative trait loci (QTL detection using substitution lines, a QTL detection was performed for scored traits. Transgressive segregation was observed for several traits measured in the population. Fourteen QTLs for plant height, tiller number per plant, panicle length, sterility percentage, 1000-grain weight and grain yield were located on chromosomes 1, 3, 4, 6 and 9. Furthermore, a highly significant QTL controlling resistance to the Rice stripe necrosis virus was located between SSR markers RM202-RM26406 (44.5-44.8 cM on chromosome 11. Conclusions Development and phenotyping of CSSL libraries with entire genome coverage represents a useful strategy for QTL discovery. Mapping of the RSNV locus represents the first identification

  12. Skin Substitutes

    OpenAIRE

    Zavan, Barbara; Vindigni, Vincenzo; Cortivo, Roberta; Abatangelo, Giovanni

    2010-01-01

    The many studies conducted so far reveal that Tissue Engineering of the skin is only at the beginning of its use in human applications. Burns patients were the first targets for such tissue substitutes, then chronic diseases, such as venous ulcers, have followed. The more experience is gained from the surgeon, the more feedback for the basic scientist to improve the product and to broaden clinical indications. Nowadays, progress in cell culture and biomedical material technologies have added ...

  13. 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.

  14. Chromosome engineering: power tools for plant genetics.

    Science.gov (United States)

    Chan, Simon W L

    2010-12-01

    The term "chromosome engineering" describes technologies in which chromosomes are manipulated to change their mode of genetic inheritance. This review examines recent innovations in chromosome engineering that promise to greatly increase the efficiency of plant breeding. Haploid Arabidopsis thaliana have been produced by altering the kinetochore protein CENH3, yielding instant homozygous lines. Haploid production will facilitate reverse breeding, a method that downregulates recombination to ensure progeny contain intact parental chromosomes. Another chromosome engineering success is the conversion of meiosis into mitosis, which produces diploid gametes that are clones of the parent plant. This is a key step in apomixis (asexual reproduction through seeds) and could help to preserve hybrid vigor in the future. New homologous recombination methods in plants will potentiate many chromosome engineering applications. PMID:20933291

  15. Dynamic changes in paternal X-chromosome activity during imprinted X-chromosome inactivation in mice

    OpenAIRE

    Patrat, Catherine; Okamoto, Ikuhiro; Diabangouaya, Patricia; Vialon, Vivian; Le Baccon, Patricia; Chow, Jennifer; Heard, Edith

    2009-01-01

    In mammals, X-chromosome dosage compensation is achieved by inactivating one of the two X chromosomes in females. In mice, X inactivation is initially imprinted, with inactivation of the paternal X (Xp) chromosome occurring during preimplantation development. One theory is that the Xp is preinactivated in female embryos, because of its previous silence during meiosis in the male germ line. The extent to which the Xp is active after fertilization and the exact time of onset of X-linked gene si...

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

    OpenAIRE

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

    2005-01-01

    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 b...

  17. Number and size of human X chromosome fragments transferred to mouse cells by chromosome-mediated gene transfer.

    OpenAIRE

    Olsen, A S; McBride, O W; Moore, D. E.

    1981-01-01

    Labeled probes of unique-sequence human X chromosomal deoxyribonucleic acid, prepared by two different procedures, were used to measure the amount of human X chromosomal deoxyribonucleic acid in 12 mouse cell lines expressing human hypoxanthine phosphoribosyltransferase after chromosome-mediated gene transfer. The amount of X chromosomal deoxyribonucleic acid detected by this procedure ranged from undetectable levels in the three stable transformants and some unstable transformants examined t...

  18. Production and characterization of an alloplasmic and monosomic addition line of Brassica rapa carrying the cytoplasm and one chromosome of Moricandia arvensis

    OpenAIRE

    Tsutsui, Kota; Jeong, Bum Hee; Ito, Yukiko; Bang, Sang Woo; Kaneko, Yukio

    2011-01-01

    Intergeneric hybridization was performed between Moricandia arvensis and four inbred lines of Brassica rapa following embryo rescue. Three F1 hybrid plants were developed from three cross combinations of M. arvensis × B. rapa, and amphidiploids were synthesized by colchicine treatment. Six BC1 plants were generated from a single cross combination of amphidipolid × B. rapa ‘Ko1-303’ through embryo rescue. One BC2 and three BC3 plants were obtained from successive backcrossing with B. rapa ‘Ko1...

  19. 普通小麦-大赖草-簇毛麦异附加、易位系的选育和鉴定%Development of Wheat-alien Lines with Added Leymus racemosus Chromosomes and 6VS/6AL Translocation Chromosomes

    Institute of Scientific and Technical Information of China (English)

    陈发棣; 陈佩度; 王苏玲

    2001-01-01

    By chromosome C-banding and bi-color fluorescence in situhybridization (FISH) using digoxigenin-labelled total genomic DNA of Leymus racemosus (Lam.) Tzvel. and biotinylated total genomic DNA of Haynaldia villosa (L.) Schur as probes, three wheat-alien lines with L. racemosus Lr.7 addition and H. villosa 6VS/6AL translocated chromosomes, and eight lines with L. racemosus Lr.14 addition and H. villosa 6VS/6AL translocated chromosomes were respectively identified from DALr.7×T6VS/6AL (93G51-4×P64) and DALr.14×T6VS/6AL (94G15×P64) F2 or F3 hybrids. Fluorescein-isothiocyanate-conjugated avidin and rhodamine-conjugated sheep anti-digoxigenin Fab fragment were used in bi-color FISH detection. The chromosomes of L.racemosus and 6VS fragment of H. villosa were simultaneously detected by their red and green fluorescence. Powdery mildew and scab resistance were also evaluated. The result showed that the obtained plants had high resistance to these two diseases. The potential usage of bi-color FISH in identifying chromatin of L.racemosus and H.villosa was discussed.%利用根尖细胞(RTC)有丝分裂中期染色体和花粉母细胞减数分裂中期Ⅰ(PMCMⅠ)染色体C分带和以生物素标记的簇毛麦基因组DNA及以地高辛标记的大赖草基因组DNA为探针的双色荧光原位杂交(bi-colorFISH),从DALr.7×T6VS/6AL(93G51-4×P64)F2和F3群体中筛选出3株普通小麦(Triticum aestivum L.)-大赖草(Leymus racemosus (Lam.) Tzvel.)Lr.7二体附加、普通小麦-簇毛麦(Haynaldia villosa (L.)Schur)6VS/6AL易位系;从DALr.14×T6VS/6AL(94G15×P64)F2和F3群体中选出8株普通小麦-大赖草Lr.14二体附加、普通小麦-簇毛麦6VS/6AL易位系。通过温室白粉病抗性鉴定和单花滴注赤霉病抗性鉴定,结果表明:所选育的普通小麦-大赖草-簇毛麦异附加、易位系对白粉病表现免疫,对赤霉病有较高抗性。还对利用双色FISH鉴定大赖草和簇毛麦染色质的

  20. Mitotic chromosome structure

    International Nuclear Information System (INIS)

    Mounting evidence is compiling linking the physical organizational structure of chromosomes and the nuclear structure to biological function. At the base of the physical organizational structure of both is the concept of loop formation. This implies that physical proximity within chromosomes is provided for otherwise distal genomic regions and thus hierarchically organizing the chromosomes. Together with entropy many experimental observations can be explained with these two concepts. Among the observations that can be explained are the measured physical extent of the chromosomes, their shape, mechanical behavior, the segregation into territories (chromosomal and territories within chromosomes), the results from chromosome conformation capture experiments, as well as linking gene expression to structural organization.

  1. Fetal chromosome analysis: screening for chromosome disease?

    DEFF Research Database (Denmark)

    Philip, J; Tabor, Ann; Bang, J;

    1983-01-01

    A + B). Pregnant women 35 years of age, women who previously had a chromosomally abnormal child, families with translocation carriers or other heritable chromosomal disease, families where the father was 50 years or more and women in families with a history of Down's syndrome (group A), were...... unbalanced chromosome abnormality in group A (women with elevated risk) is significantly higher than in group B + C (women without elevated risk) (relative risk 2.4). Women with a known familial translocation and women 40 years or more have a relative risk of 5.7 of having an unbalanced chromosome......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...

  2. 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.

  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. Hobo transposons causing chromosomal breakpoints.

    OpenAIRE

    Ladevèze, V; Aulard, S.; Chaminade, N; Périquet, G; Lemeunier, F

    1998-01-01

    Several laboratory surveys have shown that transposable elements (TEs) can cause chromosomal breaks and lead to inversions, as in dysgenic crosses involving P-elements. However, it is not presently clear what causes inversions in natural populations of Drosophila. The only direct molecular studies must be taken as evidence against the involvement of mobile elements. Here, in Drosophila lines transformed with the hobo transposable element, and followed for 100 generations, we show the appearan...

  5. Chromosomal instability determines taxane response

    OpenAIRE

    Swanton, Charles; Nicke, Barbara; Schuett, Marion; Eklund, Aron C.; Ng, Charlotte; Li, Qiyuan; Hardcastle, Thomas; Lee, Alvin; Roy, Rajat; East, Philip; Kschischo, Maik; Endesfelder, David; Wylie, Paul; Kim, Se Nyun; Chen, Jie-Guang

    2009-01-01

    Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting 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....

  6. Delayed chromosomal instability induced by DNA damage.

    OpenAIRE

    Marder, B A; Morgan, W. F.

    1993-01-01

    DNA damage induced by ionizing radiation can result in gene mutation, gene amplification, chromosome rearrangements, cellular transformation, and cell death. Although many of these changes may be induced directly by the radiation, there is accumulating evidence for delayed genomic instability following X-ray exposure. We have investigated this phenomenon by studying delayed chromosomal instability in a hamster-human hybrid cell line by means of fluorescence in situ hybridization. We examined ...

  7. 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

  8. Identification of Wheat-Agropyron cristatum 6P Chromosome Intercalary Translocation Lines%普通小麦-冰草6P染色体中间插入易位系的鉴定

    Institute of Scientific and Technical Information of China (English)

    黄琛; 张锦鹏; 刘伟华; 杨欣明; 李秀全; 鲁玉清; 李立会; 高爱农

    2013-01-01

    Distant hybridization is a practical way to introduce the chromatins carrying agronomically desirable genes of the wheat related species into the common wheat in order to enhance the diversity of the wheat genetic pool.The aim of this study was to identify the homozygous small segmental translocation lines with excellent agronomic performances among the progenies of the hybridization between wheat and alien species by using genomic in situ hybridization(GISH).In this study,the translocation progenies of the hybridization between the wheat-Agropyrum cristatum disomic substitution line 4844-8 and common wheat,and the disomic addition line 4844-12 and common wheat,were studied.Two intercalary translocation lines with a pair of small homozygous A.cristatum chromatin segments were identified with GISH respectively.The intercalary translocation line 104-3,with high thousand grain weight(TGW) was resistant to powdery mildew.The intercalary translocation line 19-2 was excellent for its high grain number per spike (GNPS) and high TGW.The excellent agronomic performances of these two lines indicated that they were elite genetic resources,and could be used to broaden the wheat genetic basis in the future.%远缘杂交技术是将小麦野生近缘植物的染色体片段导入小麦的有效途径.通过这种方法可以拓宽小麦的遗传基础,导入控制优异性状的基因,从而达到改良小麦的目的.为了获得在小麦遗传育种中具有较高研究利用价值的纯合小麦-冰草小片段异源染色体易位系,利用细胞学手段对普通小麦-冰草的远缘杂交后代进行鉴定.本研究以小麦-冰草二体代换系4844-8、二体附加系4844-12与普通小麦杂交后辐照产生的易位系为材料,利用基因组原位杂交(GISH)技术从中鉴定出2个具有冰草染色体小片段的纯合中间插入易位系,其中易位系104-3高抗小麦白粉病、高千粒重;易位系19-2具有较高的穗粒数和较

  9. 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.

  10. Identification of quantitative trait locus for abscisic acid responsiveness on chromosome 5A and association with dehydration tolerance in common wheat seedlings.

    Science.gov (United States)

    Iehisa, Julio C M; Matsuura, Takakazu; Mori, Izumi C; Takumi, Shigeo

    2014-01-15

    The phytohormone abscisic acid (ABA) plays important roles in response to environmental stress as well as in seed maturation and dormancy. In common wheat, quantitative trait loci (QTLs) for ABA responsiveness at the seedling stage have been reported on chromosomes 1B, 2A, 3A, 6D and 7B. In this study, we identified a novel QTL for ABA responsiveness on chromosome 5A using an F2 population derived from a cross between the common wheat cultivar Chinese Spring (CS) and a chromosome substitution line of CS with chromosome 5A of cultivar Hope (Hope5A). This QTL was found in a similar chromosomal region to previously reported QTLs for drought tolerance and seed dormancy. Physiological characterization of the QTL revealed a small effect on dehydration tolerance and seed dormancy. The rate of water loss from leaves during dehydration was lower, and transcript accumulation of the cold responsive (COR)/late embryogenesis abundant (LEA) genes Wrab18 and Wdhn13 tended to be higher under dehydration stress in F2 individuals carrying the Hope allele of the QTL, which also showed higher ABA responsiveness than the CS allele-carrying individuals. Seed dormancy of individuals carrying the Hope allele also tended to be lower than those carrying the CS allele. Our results suggest that variation in ABA responsiveness among common wheat cultivars is at least partly determined by the 5A QTL, and that this QTL contributes to development of dehydration and preharvest sprouting tolerance. PMID:24331416

  11. Study of ionizing radiation effect on human spermatozoa chromosomes

    International Nuclear Information System (INIS)

    The purpose of this thesis is to study the radio-induced chromosomal aberrations in spermatozoa. After a brief recall on ionizing radiations, the author reviews the radio-induced chromosomal anomalies on somatic cells and on germinal line cells and spermatozoa. The author presents the technical aspects of human spermatozoa karyotype and finally studies the radio induced chromosomal anomalies of sperm to patients undergoing a radiotherapy. 13 tabs., 28 figs., 28 photos

  12. Chimpanzee chromosome 12 is homologous to human chromosome 2q

    Energy Technology Data Exchange (ETDEWEB)

    Sun, N. C.; Sun, C. R.Y.; Ho, T.

    1977-01-01

    Most of the 46 human chromosomes find their counterparts in the 48 chimpanzee chromosomes except for chromosome 2 which has been hypothesized to have been derived from a centric fusion of two chimpanzee acrocentric chromosomes. These two chromosomes correspond to the human chromosomes 2p and 2g. This conclusion is based primarily on chromosome banding techniques, and the somatic cell hybridization technique has also been used. (HLW)

  13. 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.

  14. 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...

  15. Industrialisation: Import Substitution to Export Promotion

    OpenAIRE

    Jayanthakumaran, K.

    2000-01-01

    Import-substitution policy creates biases in the incentive structure and lowers the growth of potential exports in the long run. Trade reforms in this respect are likely to reduce the gap between domestic and border prices. The expectation is to bring better industrial performance on the lines of comparative advantages. This paper examines the import-substitution policy and the effect and impact of trade liberalisation.

  16. Chromatin structure and ionizing-radiation-induced chromosome aberrations

    International Nuclear Information System (INIS)

    The possible influence of chromatic structure or activity on chromosomal radiosensitivity was studied. A cell line was isolated which contained some 105 copies of an amplified plasmid in a single large mosquito artificial chromosome (MAC). This chromosome was hypersensitive to DNase I. Its radiosensitivity was some three fold greater than normal mosquito chromosomes in the same cell. In cultured human cells irradiated during G0, the initial breakage frequency in chromosome 4, 19 and the euchromatic and heterochromatic portions of the Y chromosome were measured over a wide range of doses by inducing Premature Chromosome Condensation (PCC) immediately after irradiation with Cs-137 gamma rays. No evidence was seen that Y heterochromatin or large fragments of it remained unbroken. The only significant deviation from the expected initial breakage frequency per Gy per unit length of chromosome was that observed for the euchromatic portion of the Y chromosome, with breakage nearly twice that expected. The development of aberrations involving X and Y chromosomes at the first mitosis after irradation was also studied. Normal female cells sustained about twice the frequency of aberrations involving X chromosomes for a dose of 7.3 Gy than the corresponding male cells. Fibroblasts from individuals with supernumerary X chromosomes did not show any further increase in X aberrations for this dos. The frequency of aberrations involving the heterochromatic portion of the long arm of the Y chromosome was about what would be expected for a similar length of autosome, but the euchromatic portion of the Y was about 3 times more radiosensitive per unit length. 5-Azacytidine treatment of cultured human female fibroblasts or fibroblasts from a 49,XXXXY individual, reduced the methylation of cytosine residues in DNA, and resulted in an increased chromosomal radiosensitivity in general, but it did not increase the frequency of aberrations involving the X chromosomes

  17. Chromosome substitution strains: gene discovery, functional analysis, and systems studies

    Czech Academy of Sciences Publication Activity Database

    Nadeau, J. H.; Forejt, Jiří; Takada, T.; Shiroishi, T.

    2012-01-01

    Roč. 23, 9-10 (2012), s. 693-705. ISSN 0938-8990 Grant ostatní: AV ČR(CZ) Praemium Academiae Institutional research plan: CEZ:AV0Z50520514 Institutional support: RVO:68378050 Keywords : consomic strains * QTL mapping * transgenerational effects Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.419, year: 2012

  18. 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...

  19. Meiotic chromosomal variation resulting from irradiation of pollen in maize

    International Nuclear Information System (INIS)

    The objective of this study was to standardize an induction strategy of chromosome aberrations in maize inbred line L-869. Pollen grains irradiated with 0, 36 and 72 Gy were used for fertilization. Resulting seeds were planted in a greenhouse to assess the number of abnormal meiotic cells. Germination, height, sterility and mortality were verified. Cells with delayed separation of chromosomes, translocation, deficiency, abnormal pairing, later condensation and anaphase bridges were observed. The number of abnormalities increased as the dosage increased but chromosome aberration types were the same regardless of the dosages used. Various chromosome-altered plants were obtained without viability loss. (author)

  20. Asymmetry and skin pigmentary anomalies in chromosome mosaicism.

    OpenAIRE

    WOODS, C. G.; BANKIER, A.; J Curry; Sheffield, L J; Slaney, S F; Smith, K.; Voullaire, L; Wellesley, D.

    1994-01-01

    We report six persons mosaic for a chromosome anomaly. All were mentally retarded and dysmorphic. Unilateral or asymmetrical features were found in all cases, in one an unusual transverse terminal limb anomaly, and in the others various degrees of hemiatrophy of the left side of the body. Five of the subjects had skin pigmentary anomalies which were distributed in the lines of Blaschko. The abnormal cell lines found were ring chromosome 22, trisomy 22, a large acrocentric marker, a deletion o...

  1. Plant sex chromosome evolution.

    Science.gov (United States)

    Charlesworth, Deborah

    2013-01-01

    It is now well established that plants have an important place in studies of sex chromosome evolution because of the repeated independent evolution of separate sexes and sex chromosomes. There has been considerable recent progress in studying plant sex chromosomes. In this review, I focus on how these recent studies have helped clarify or answer several important questions about sex chromosome evolution, and I shall also try to clarify some common misconceptions. I also outline future work that will be needed to make further progress, including testing some important ideas by genetic, molecular, and developmental approaches. Systems with different ages can clearly help show the time course of events during changes from an ancestral co-sexual state (hermaphroditism or monoecy), and I will also explain how different questions can be studied in lineages whose dioecy or sex chromosomes evolved at different times in the past. PMID:23125359

  2. Vibrio chromosomes share common history

    OpenAIRE

    Gevers Dirk; Chang Sarah; Chang LeeAnn; Kirkup Benjamin C; Polz Martin F

    2010-01-01

    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 ...

  3. Fractal dual substitution tilings

    OpenAIRE

    Frank, Natalie Priebe; Webster, Samuel B. G.; Whittaker, Michael F.

    2014-01-01

    Starting with a substitution tiling, we demonstrate a method for constructing infinitely many new substitution tilings. Each of these new tilings is derived from a graph iterated function system and the tiles have fractal boundary. We show that each of the new tilings is mutually locally derivable to the original tiling. Thus, at the tiling space level, the new substitution rules are expressing geometric and combinatorial, rather than topological, features of the original. Our method is easy ...

  4. 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

  5. Syndeticity and independent substitutions

    CERN Document Server

    Durand, Fabien

    2009-01-01

    We associate in a canonical way a substitution to any abstract numeration system built on a regular language. In relationship with the growth order of the letters, we define the notion of two independent substitutions. Our main result is the following. If a sequence $x$ is generated by two independent substitutions, at least one being of exponential growth, then the factors of $x$ appearing infinitely often in $x$ appear with bounded gaps. As an application, we derive an analogue of Cobham's theorem for two independent substitutions (or abstract numeration systems) one with polynomial growth, the other being exponential.

  6. Irradiation-Induced Wheat-Alien Translocation Lines and their Application in Wheat Breeding

    International Nuclear Information System (INIS)

    Wild relatives are rich gene resources for wheat improvement. Transfer of useful alien genes to wheat through development of wheat-alien translocations, especially small alien segment translocations, is important for wheat breeding. Wheat-alien genetic stocks such as amphiploid, addition or substitution lines were irradiated for translocation induction. Mature male or female gametes before flowering on the spikes were irradiated by 60Co-Gamma-rays at doses ranging from 800 to 2240 rad. Chromosome C-banding and genomic in situ hybridization (GISH) was used to identify chromosome translocation. Backcross of M1 plants using normal fresh pollen of common wheat was employed to enhance the transmission rate of various structural changes in their progenies. The results showed that a dose of 800∼1200 rad was suitable for pollen irradiation while 1500∼2000 rad was suitable for female-gamete irradiation. Irradiation treatment just before gamete maturation is advantageous to acquire more M1 hybrids with a high frequency of chromosome structural variation. The frequency of plants with at least one translocation chromosome in M1 could be increased up to 70% through pollen irradiation of Triticum durum-Haynaldia villosa amphiploid. More than 100 translocated chromosomes have been identified in the BC1 and BC2. Translocations with small alien chromosome segments, 57 terminal and 80 intercalary, were induced through female gamete irradiation conducted on T.aestivum-H.villosa 6VS/6AL translocation line. For the 2240 Rad dosage treatment, the induction 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 T.aestivum-H.villosa 6VS/6AL translocation has been used in wheat breeding and many elite cultivars, such as Nannong 9918, Neimai 9, Shimai 14, etc. have been developed and released. (author)

  7. Sequential cloning of chromosomes

    Energy Technology Data Exchange (ETDEWEB)

    Lacks, S.A.

    1991-12-31

    A method for sequential cloning of chromosomal DNA and chromosomal DNA cloned by this method are disclosed. The method includes the selection of a target organism having a segment of chromosomal DNA to be sequentially cloned. A first DNA segment, having a first restriction enzyme site on either side. homologous to the chromosomal DNA to be sequentially cloned is isolated. 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 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.

  8. 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.

  9. 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

  10. A new chromosome was born: comparative chromosome painting in Boechera.

    Science.gov (United States)

    Koch, Marcus A

    2015-09-01

    Comparative chromosome painting is a powerful tool to study the evolution of chromosomes and genomes. Analyzing karyotype evolution in cruciferous plants highlights the origin of aberrant chromosomes in apomictic Boechera and further establishes the cruciferous plants as important model system for our understanding of plant chromosome and genome evolution. PMID:26228436

  11. Chimpanzee chromosome 13 is homologous to human chromosome 2p

    Energy Technology Data Exchange (ETDEWEB)

    Sun, N. C.; Sun, C. R.Y.; Ho, T.

    1977-01-01

    Similarities between human and chimpanzee chromosomes are shown by chromosome banding techniques and somatic cell hybridization techniques. Cell hybrids were obtained from the chimpanzee lymphocyte LE-7, and the Chinese hamster mutant cell, Gal-2. Experiments showed that the ACPL, MDHs, and Gal-Act genes could be assigned to chimpanzee chromosome 13, and since these genes have been assigned to human chromosme 2p, it is suggested that chimpanzee chromosome 13 is homologous to human chromosome 2p. (HLW)

  12. Chromosome condensation and segmentation

    International Nuclear Information System (INIS)

    Some aspects of chromosome condensation in mammalians -humans especially- were studied by means of cytogenetic techniques of chromosome banding. Two further approaches were adopted: a study of normal condensation as early as prophase, and an analysis of chromosome segmentation induced by physical (temperature and γ-rays) or chemical agents (base analogues, antibiotics, ...) in order to show out the factors liable to affect condensation. Here 'segmentation' means an abnormal chromosome condensation appearing systematically and being reproducible. The study of normal condensation was made possible by the development of a technique based on cell synchronization by thymidine and giving prophasic and prometaphasic cells. Besides, the possibility of inducing R-banding segmentations on these cells by BrdU (5-bromodeoxyuridine) allowed a much finer analysis of karyotypes. Another technique was developed using 5-ACR (5-azacytidine), it allowed to induce a segmentation similar to the one obtained using BrdU and identify heterochromatic areas rich in G-C bases pairs

  13. 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.

  14. Chromosome numbers in Bromeliaceae

    OpenAIRE

    2000-01-01

    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. u...

  15. Micromechanics of human mitotic chromosomes

    International Nuclear Information System (INIS)

    Eukaryote cells dramatically reorganize their long chromosomal DNAs to facilitate their physical segregation during mitosis. The internal organization of folded mitotic chromosomes remains a basic mystery of cell biology; its understanding would likely shed light on how chromosomes are separated from one another as well as into chromosome structure between cell divisions. We report biophysical experiments on single mitotic chromosomes from human cells, where we combine micromanipulation, nano-Newton-scale force measurement and biochemical treatments to study chromosome connectivity and topology. Results are in accord with previous experiments on amphibian chromosomes and support the 'chromatin network' model of mitotic chromosome structure. Prospects for studies of chromosome-organizing proteins using siRNA expression knockdowns, as well as for differential studies of chromosomes with and without mutations associated with genetic diseases, are also discussed

  16. 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.

  17. Chromosome polymorphism in a population of ceratitis capitata

    International Nuclear Information System (INIS)

    A morphological chromosomal polymorphism along with the observation of B chromosomes in a natural population of Ceratitis capitata is reported. A variability affecting the centromere size of chromosome 3 is described. The observed B chromosome is minute, heterochromatic and telocentric. The B chromosome was found in the male and female germ cells and it exhibited, in the males, intra-individual numerical variation with OB and IB cells, which suggested a mitotic instability. It was also found, in both sexes, in somatic cells (cerebral ganglia tissue). Only males transmitted the B chromosomes to the progeny. The high rate of transmission suggested a differential utilization of the sperm carrying the B chromosomes or a preferential segregation into secondary spermatocytes. Previously reported linkage relationship between a pupal esterase gene (Est-1) and a pupa colour mutant (nig) has been extended to a line carrying a Y-chromosome (Y,B) shorter than the one previously studied (Y,A). Furthermore, an elaborate crossing scheme has been devised in order to estimate the recombination distances between these two genes and a third one affecting pupal length (lp-1). It is concluded that all three genes are in the same linkage group but Est-1 is far from the other two. In turn, nig and lp-1 are separated by 14.9 map units. It is confirmed that genetic recombination does not regularly occur at high frequency in the male and this frequency is not increased by the varying length of the Y-chromosome. Refs, figs, tabs

  18. Synthesis and anti-proliferative activity of aromatic substituted 5-((1-benzyl-1H-indol-3-yl)methylene)-1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)-trione analogs against human tumor cell lines.

    Science.gov (United States)

    Madadi, Nikhil Reddy; Penthala, Narsimha Reddy; Janganati, Venumadhav; Crooks, Peter A

    2014-01-15

    Based on previous SAR studies on N-benzylindole and barbituric acid hybrid molecules, we have synthesized a series of aromatic substituted 5-((1-benzyl-1H-indol-3-yl)methylene)-1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)-trione analogs (3a-i) and evaluated them for their in vitro growth inhibition and cytotoxicity against a panel of 60 human tumor cell lines. Compounds 3c, 3d, 3f and 3g were identified as highly potent anti-proliferative compounds against ovarian, renal and breast cancer cell lines with GI50 values in low the nanomolar range. The 4-methoxy-N-benzyl analog (3d) was the most active compound with GI50 values of 20 nM and 40 nM against OVCAR-5 ovarian cancer cells and MDA-MB-468 breast cancer cells, respectively. Two other analogs, 3c (the 4-methyl-N-benzyl analog) and 3g (the 4-fluoro-N-benzyl analog) exhibited equimolar potency against MDA-MB-468 cells GI50=30 nM). Analog 3f (the 4-chloro-N-benzyl analog) exhibited a GI50 value of 40 nM against renal cancer cell line A498. These results suggest that aromatic substituted N-benzylindole dimethylbarbituric acid hybrids may have potential for development as clinical candidates to treat a variety of solid tumors. PMID:24361000

  19. 40 CFR 721.981 - Substituted naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex.

    Science.gov (United States)

    2010-07-01

    ... naphthalenyl-substituted azonaphthol chromium complex. 721.981 Section 721.981 Protection of Environment...-substituted naphthalenyl-substituted azonaphthol chromium complex. (a) Chemical substance and significant new... naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex (PMN P-93-1631) is subject...

  20. Human embryonic stem cells as models for aneuploid chromosomal syndromes.

    Science.gov (United States)

    Biancotti, Juan-Carlos; Narwani, Kavita; Buehler, Nicole; Mandefro, Berhan; Golan-Lev, Tamar; Yanuka, Ofra; Clark, Amander; Hill, David; Benvenisty, Nissim; Lavon, Neta

    2010-09-01

    Syndromes caused by chromosomal aneuploidies are widely recognized genetic disorders in humans and often lead to spontaneous miscarriage. Preimplantation genetic screening is used to detect chromosomal aneuploidies in early embryos. Our aim was to derive aneuploid human embryonic stem cell (hESC) lines that may serve as models for human syndromes caused by aneuploidies. We have established 25 hESC lines from blastocysts diagnosed as aneuploid on day 3 of their in vitro development. The hESC lines exhibited morphology and expressed markers typical of hESCs. They demonstrated long-term proliferation capacity and pluripotent differentiation. Karyotype analysis revealed that two-third of the cell lines carry a normal euploid karyotype, while one-third remained aneuploid throughout the derivation, resulting in eight hESC lines carrying either trisomy 13 (Patau syndrome), 16, 17, 21 (Down syndrome), X (Triple X syndrome), or monosomy X (Turner syndrome). On the basis of the level of single nucleotide polymorphism heterozygosity in the aneuploid chromosomes, we determined whether the aneuploidy originated from meiotic or mitotic chromosomal nondisjunction. Gene expression profiles of the trisomic cell lines suggested that all three chromosomes are actively transcribed. Our analysis allowed us to determine which tissues are most affected by the presence of a third copy of either chromosome 13, 16, 17 or 21 and highlighted the effects of trisomies on embryonic development. The results presented here suggest that aneuploid embryos can serve as an alternative source for either normal euploid or aneuploid hESC lines, which represent an invaluable tool to study developmental aspects of chromosomal abnormalities in humans. PMID:20641042

  1. Cobham's theorem for substitutions

    CERN Document Server

    Durand, Fabien

    2010-01-01

    The seminal theorem of Cobham has given rise during the last 40 years to a lot of works around non-standard numeration systems and has been extended to many contexts. In this paper, as a result of fifteen years of improvements, we obtain a complete and general version for the so-called substitutive sequences. Let $\\alpha$ and $\\beta$ be two multiplicatively independent Perron numbers. Then, a sequence $x\\in A^\\mathbb{N}$, where $A$ is a finite alphabet, is both $\\alpha$-substitutive and $\\beta$-substitutive if and only if $x$ is ultimately periodic.

  2. Chromosomal instability determines taxane response.

    Science.gov (United States)

    Swanton, Charles; Nicke, Barbara; Schuett, Marion; Eklund, Aron C; Ng, Charlotte; Li, Qiyuan; Hardcastle, Thomas; Lee, Alvin; Roy, Rajat; East, Philip; Kschischo, Maik; Endesfelder, David; Wylie, Paul; Kim, Se Nyun; Chen, Jie-Guang; Howell, Michael; Ried, Thomas; Habermann, Jens K; Auer, Gert; Brenton, James D; Szallasi, Zoltan; Downward, Julian

    2009-05-26

    Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting 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-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 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. PMID:19458043

  3. Strong selective sweeps associated with ampliconic regions in great ape X chromosomes

    DEFF Research Database (Denmark)

    Nam, Kiwoong; Munch, Kasper; Hobolth, Asger;

    2014-01-01

    The unique inheritance pattern of X chromosomes makes them preferential targets of adaptive evolution. We here investigate natural selection on the X chromosome in all species of great apes. We find that diversity is more strongly reduced around genes on the X compared with autosomes, and that a ...... ampliconic sequences we propose that intra-genomic conflict between the X and the Y chromosomes is a major driver of X chromosome evolution.......The unique inheritance pattern of X chromosomes makes them preferential targets of adaptive evolution. We here investigate natural selection on the X chromosome in all species of great apes. We find that diversity is more strongly reduced around genes on the X compared with autosomes, and that a...... higher proportion of substitutions results from positive selection. Strikingly, the X exhibits several megabase long regions where diversity is reduced more than five fold. These regions overlap significantly among species, and have a higher singleton proportion, population differentiation, and...

  4. Electricity/oil substitution

    International Nuclear Information System (INIS)

    The extent to which electricity could substitute for imported oil in Canada is assessed and it is concluded that the bulk of projected oil imports could be displaced. This substitution of electricity for oil could be largely completed within two decades, with existing technology, using Canadian resources. The substitution of electricity for imported oil would result in relatively low energy costs and would stimulate economic growth. Energy self-sufficiency through the substitution of electricity for oil is uniquely a Canadian option; it is not open to other industrial countries. The option exists because of Canada's resources of oil sands for essential liquid fuels, hydraulic and nuclear electrical potential, and natural gas as an interim source of energy. While other countries face an energy crisis due to declining supplies of oil, Canada faces opportunities. The policies of Federal and Provincial governments, as perceived by individual decision makers, will have a major influence on Canada's ability to realize opportunities. (auth)

  5. Substitution of Si in SAPO-5

    Science.gov (United States)

    Wang, Xingqiao; Liu, Xinsheng; Song, Tianyou; Hu, Jianzhi; Qiu, Jianqing

    1989-04-01

    A series of SAPO-5 samples with different numbers of silicon atoms are investigated by chemical analysis, XRD and CP/MAS NMR. The results indicate that the lines at about -102 and -110 ppm observed in the 29Si NMR spectra of the SAPO-5 samples are due to the non-framework silicon phase which is structurally similar to the synthesis gel. The corrected framework compositions of SAPO-5 samples strongly suggest that Si is only substituted by framework P (case 2). Si simultaneously substituted by both framework P and Al (case 3) is unlikely.

  6. Breeding of Chromosome Translocation Line and F1 Hybrid with Reduced Seed in the Fruit of Watermelon%诱变选育西瓜染色体易位系的步骤及其杂交1代少籽组合的选配

    Institute of Scientific and Technical Information of China (English)

    吴进义; 吴逸华; 谢锡林

    2013-01-01

    用60Coγ射线辐照干种子诱变培育西瓜染色体易位系,并用其进行选配少籽杂交子1代研究,对克服三倍体无籽西瓜种子发芽率低、成苗率低、制种成本高、育苗技术较复杂的缺陷具有重要的意义;易位系杂交子1代西瓜保持了二倍体杂交1代的优良特性,减少了单瓜籽粒数,提高了果实可溶性固形物含量,从而提高了西瓜品质和商品价值.详细介绍了诱变选育西瓜易位系的步骤和技术、易位系的特征特性和优良的西瓜染色体易位杂交1代组合,并针对选育的科丰黑美人、红牡丹等易位系杂交1代分析阐述了染色体易位系杂交一代的优点和应用前景.%The hybrids of watermelon chromosome translocation lines induced by 60Coγ radiation can produce fruit with few seed. This is a favorable option over the triploid seedless watermelon with the challenges of low germination, poor seedling establishment,high cost of seed production,and high technical requirement of transplant production. The F1 hybrid of chromosome translocation lines,in addition to the benefits of regular diploids hybrids,produce fruits with significantly reduced number of seed but increased soluble solid contents,therefore better fruit quality and commercial value. We here describe the procedure and techniques of chromosome translocation induction and selection. We use the examples of Kefeng Heimeiren and Hong Mudan to illustrate the benefits and application of hybrid watermelon with chromosome translocation.

  7. Chromosomal instability determines taxane sensitivity - supplementary materials

    OpenAIRE

    Swanton, Charles; Nicke, Barbara; Schuett, Marion; Eklund, Aron C.; Ng, Charlotte; Li, Qiyuan; Hardcastle, Thomas; Lee, Alvin; Roy, Rajat; East, Philip; Kschischo, Maik; Endesfelder, David; Wylie, Paul; Kim, Se Nyun; Chen, Jie-Guang

    2009-01-01

    Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting 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....

  8. 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.

  9. 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.

  10. 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.

  11. An approach to automated chromosome analysis

    International Nuclear Information System (INIS)

    The methods of approach developed with a view to automatic processing of the different stages of chromosome analysis are described in this study divided into three parts. Part 1 relates the study of automated selection of metaphase spreads, which operates a decision process in order to reject ail the non-pertinent images and keep the good ones. This approach has been achieved by Computing a simulation program that has allowed to establish the proper selection algorithms in order to design a kit of electronic logical units. Part 2 deals with the automatic processing of the morphological study of the chromosome complements in a metaphase: the metaphase photographs are processed by an optical-to-digital converter which extracts the image information and writes it out as a digital data set on a magnetic tape. For one metaphase image this data set includes some 200 000 grey values, encoded according to a 16, 32 or 64 grey-level scale, and is processed by a pattern recognition program isolating the chromosomes and investigating their characteristic features (arm tips, centromere areas), in order to get measurements equivalent to the lengths of the four arms. Part 3 studies a program of automated karyotyping by optimized pairing of human chromosomes. The data are derived from direct digitizing of the arm lengths by means of a BENSON digital reader. The program supplies' 1/ a list of the pairs, 2/ a graphic representation of the pairs so constituted according to their respective lengths and centromeric indexes, and 3/ another BENSON graphic drawing according to the author's own representation of the chromosomes, i.e. crosses with orthogonal arms, each branch being the accurate measurement of the corresponding chromosome arm. This conventionalized karyotype indicates on the last line the really abnormal or non-standard images unpaired by the program, which are of special interest for the biologist. (author)

  12. Tracking alien chromosome in sativa background by genomic in situ hybridization

    International Nuclear Information System (INIS)

    Genomic in situ hybridization (GISH) was used to look into the genomic constitution of monosomic alien -addition line derived from O. sativa x O. brachyantha. Biotin label genomic DNA from O. brachyantha was used as probe. The probe hybridized to the brachyantha chromosome. No detectable hybridization signal was observed on sativa chromosomes. This differential painting of chromosome enables us to unequivocally discriminate brachyantha chromosome from those of sativa. Results showed the usefulness of GISH in the identification of a single alien chromosome in the sativa background. (author)

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

    Czech Academy of Sciences Publication Activity Database

    Bhattacharyya, Tanmoy; Reifová, R.; Gregorová, Soňa; Šimeček, Petr; Gergelits, Václav; Mistrik, M.; Martincová, Iva; Piálek, Jaroslav; Forejt, Jiří

    2014-01-01

    Roč. 10, č. 2 (2014), e1004088. ISSN 1553-7404 R&D Projects: GA AV ČR Premium Academiae of the Academy of Sciences of the Czech Republic; GA MŠk(CZ) LD11079; GA ČR GA206/08/0640; GA MŠk ED1.1.00/02.0109 Institutional support: RVO:68081766 ; RVO:68378050 Keywords : hybrid sterility * meiotic asynapsis * chromosome substitution strains Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 8.167, year: 2013

  14. Evaluating the Y chromosomal timescale in human demographic and lineage dating.

    Science.gov (United States)

    Wang, Chuan-Chao; Gilbert, M Thomas P; Jin, Li; Li, Hui

    2014-01-01

    Y chromosome is a superb tool for inferring human evolution and recent demographic history from a paternal perspective. However, Y chromosomal substitution rates obtained using different modes of calibration vary considerably, and have produced disparate reconstructions of human history. Here, we discuss how substitution rate and date estimates are affected by the choice of different calibration points. We argue that most Y chromosomal substitution rates calculated to date have shortcomings, including a reliance on the ambiguous human-chimpanzee divergence time, insufficient sampling of deep-rooting pedigrees, and using inappropriate founding migrations, although the rates obtained from a single pedigree or calibrated with the peopling of the Americas seem plausible. We highlight the need for using more deep-rooting pedigrees and ancient genomes with reliable dates to improve the rate estimation. PMID:25215184

  15. 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.

  16. Phenolic content variability and its chromosome location in tritordeum

    OpenAIRE

    Navas-Lopez, José F.; Ostos-Garrido, Francisco J.; Castillo, Almudena; Martín, Antonio; Gimenez, Maria J.; Pistón, Fernando

    2014-01-01

    For humans, wheat is the most important source of calories, but it is also a source of antioxidant compounds that are involved in the prevention of chronic disease. Among the antioxidant compounds, phenolic acids have great potential to improve human health. In this paper we evaluate the effect of environmental and genetic factors on the phenolics content in the grain of a collection of tritordeums with different cytoplasm and chromosome substitutions. To this purpose, tritordeum flour was us...

  17. Turner Syndrome with Pseudodicentric Y Chromosome Mosaicism

    OpenAIRE

    Hsieh, Yao-Yuan; Lin, Wu-Chou; Chang, Chi-Chen; Tsai, Fuu-Jen; Yu, Ming-Tsung; Tsai, Horng-Der; Tsai, Chang-Hai

    2002-01-01

    The objective was to compare the impact of gonadal cell line upon the phenotype of a Turner syndrome patient with mosaic karyotypes. A 10-year-old female presented with typical Turner syndrome. Chromosomal analysis of lymphocytes revealed 45,X (16%)/46,X,pseudodicentric Y (p ter→q12::q12→p ter) (84%). Karyotype of the gonads revealed 45,X (85%)/46,X,pseudodicentric Y (p ter→q12::q12→p ter) (15%). Discrepancy of the individual cell lines between the lymphocytes and the tissue might exist. The ...

  18. The substitutability of reinforcers.

    Science.gov (United States)

    Green, Leonard; Freed, Debra E

    1993-07-01

    Substitutability is a construct borrowed from microeconomics that describes a continuum of possible interactions among the reinforcers in a given situation. Highly substitutable reinforcers, which occupy one end of the continuum, are readily traded for each other due to their functional similarity. Complementary reinforcers, at the other end of the continuum, tend to be consumed jointly in fairly rigid proportion, and therefore cannot be traded for one another except to achieve that proportion. At the center of the continuum are reinforcers that are independent with respect to each other; consumption of one has no influence on consumption of another. Psychological research and analyses in terms of substitutability employ standard operant conditioning paradigms in which humans and nonhumans choose between alternative reinforcers. The range of reinforcer interactions found in these studies is more readily accommodated and predicted when behavior-analytic models of choice consider issues of substitutability. New insights are gained into such areas as eating and drinking, electrical brain stimulation, temporal separation of choice alternatives, behavior therapy, drug use, and addictions. Moreover, the generalized matching law (Baum, 1974) gains greater explanatory power and comprehensiveness when measures of substitutability are included. PMID:16812696

  19. Ring chromosome 13

    DEFF Research Database (Denmark)

    Brandt, C A; Hertz, Jens Michael; Petersen, M B; Vogel, F; Noer, H; Mikkelsen, M

    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 with...

  20. 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…

  1. 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.

  2. Chromosomes, cancer and radiosensitivity

    International Nuclear Information System (INIS)

    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

  3. Chromosome Morphology in Kniphofia.

    Directory of Open Access Journals (Sweden)

    J. M. J de Wet

    1960-12-01

    Full Text Available A number of species and varieties of the genus  Kniphofia (Liliaceae were studied cytologically. The somatic chromosome number is  2n = 12 in all the species. This is also true in  Notosceptrum natalense Baker.

  4. Prediction of human cell radiosensitivity: Comparison of clonogenic assay with chromosome aberrations scored using premature chromosome condensation with fluorescence in situ hybridization

    International Nuclear Information System (INIS)

    The purpose of the present investigation was to determine whether chromosome aberrations scored by premature chromosome condensation (PCC) and fluorescence in situ hybridization (FISH) can predict the radiosensitivity of human cell lines, thereby providing a possible means of assessing the in situ radiosensitivity of normal tissues and the radiocurability of individual human cancers. We used four cells lines of different radiosensitivity: normal human fibroblasts (AG1522), ataxia-telangiectasia fibroblasts (AT2052), a human fibrosarcoma cell line (HT1080), and a human melanoma cell line (melanoma 903). These were irradiated in plateau phase with a range of doses and assessed both for clonogenic cell survival and for aberrations in a single chromosome (number 4) immediately after, and 24 h after irradiation. The initial number of breaks in chromosome 4 was proportional to irradiation dose and was identical for all the different human cell lines, irrespective of radiosensitivity. On the other hand, the number of chromosome 4 breaks remaining 24 h after irradiation reflected the radiosensitivity of the cells such that the relationship between residual chromosome aberrations and cell survival was the same for the different cell lines. These results suggest that the scoring of chromosome aberrations in interphase using FISH with PCC holds considerable promise for predicting the radiosensitivity of normal and tumor tissues in situ. 28 refs., 4 figs

  5. 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

  6. Organization of the bacterial chromosome.

    OpenAIRE

    Krawiec, S.; Riley, M

    1990-01-01

    Recent progress in studies on the bacterial chromosome is summarized. Although the greatest amount of information comes from studies on Escherichia coli, reports on studies of many other bacteria are also included. A compilation of the sizes of chromosomal DNAs as determined by pulsed-field electrophoresis is given, as well as a discussion of factors that affect gene dosage, including redundancy of chromosomes on the one hand and inactivation of chromosomes on the other hand. The distinction ...

  7. 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.

  8. Geometric realizations of substitutive tilings

    CERN Document Server

    Bedaride, Nicolas

    2011-01-01

    We define 2-dimensional topological substitutions. A tiling of the Euclidean plane, or of the hyperbolic plane, is substitutive if the underlying 2-complex can be obtained by iteration of a 2-dimensional topological substitution. We prove that there is no primitive substitutive tiling of the hyperbolic plane $\\mathbb{H}^2$. However, we give an example of substitutive tiling of $\\Hyp^2$ which is non-primitive.

  9. [Delegation yes, substitution no!].

    Science.gov (United States)

    Schroeder, A

    2014-08-01

    The aging of society leads on the one hand to increasing case numbers and on the other hand to a reduction in the number of physicians available for patient treatment. The delegation and substitution of medical duties as a tried and tested method is increasingly being recommended in order to compensate for the lack of physicians. The Berufsverband der Deutschen Urologen (BDU, Professional Association of German Urologists) supports the guiding principle of the Bundesärztekammer (Federal Medical Council) of "delegation yes, substitution no" and rejects a substitution of medical duties by non-medical academic health personnel. Against the background of the demographic changes, the increasing need for treatment and the current deficiency of junior physicians, a more extensive inclusion of well-qualified and experienced non-medical personnel by the delegation of medically responsible duties (medical scope of practice) can be an appropriate measure to maintain a good medical service in practices, hospitals and nursing homes. PMID:25047595

  10. Chromosome mapping of repetitive sequences in Anostomidae species: implications for genomic and sex chromosome evolution

    Directory of Open Access Journals (Sweden)

    da Silva Edson Lourenço

    2012-12-01

    typical of Long Interspersed Elements (LINEs. The differential distribution of this element may be linked to sex chromosome differentiation in L. elongatus species. The relationship between sex chromosome specificity and the LeSpeI element is confirmed in the species L. elongatus, L. macrocephalus and L. obtusidens.

  11. 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.

  12. Dynamic changes in paternal X-chromosome activity during imprinted X-chromosome inactivation in mice.

    Science.gov (United States)

    Patrat, Catherine; Okamoto, Ikuhiro; Diabangouaya, Patricia; Vialon, Vivian; Le Baccon, Patricia; Chow, Jennifer; Heard, Edith

    2009-03-31

    In mammals, X-chromosome dosage compensation is achieved by inactivating one of the two X chromosomes in females. In mice, X inactivation is initially imprinted, with inactivation of the paternal X (Xp) chromosome occurring during preimplantation development. One theory is that the Xp is preinactivated in female embryos, because of its previous silence during meiosis in the male germ line. The extent to which the Xp is active after fertilization and the exact time of onset of X-linked gene silencing have been the subject of debate. We performed a systematic, single-cell transcriptional analysis to examine the activity of the Xp chromosome for a panel of X-linked genes throughout early preimplantation development in the mouse. Rather than being preinactivated, we found the Xp to be fully active at the time of zygotic gene activation, with silencing beginning from the 4-cell stage onward. X-inactivation patterns were, however, surprisingly diverse between genes. Some loci showed early onset (4-8-cell stage) of X inactivation, and some showed extremely late onset (postblastocyst stage), whereas others were never fully inactivated. Thus, we show that silencing of some X-chromosomal regions occurs outside of the usual time window and that escape from X inactivation can be highly lineage specific. These results reveal that imprinted X inactivation in mice is far less concerted than previously thought and highlight the epigenetic diversity underlying the dosage compensation process during early mammalian development. PMID:19273861

  13. [Chromosomal organization of the genomes of small-chromosome plants].

    Science.gov (United States)

    Muravenko, O V; Zelenin, A V

    2009-11-01

    An effective approach to study the chromosome organization in genomes of plants with small chromosomes and/or with low-informative C-banding patterns was developed in the course of investigation of the karyotypes of cotton plant, camomile, flax, and pea. To increase the resolving power of chromosome analysis, methods were worked out for revealing early replication patterns on chromosomes and for artificial impairment of mitotic chromosome condensation with the use of a DNA intercalator, 9-aminoacridine (9-AMA). To estimate polymorphism of the patterns of C-banding of small chromosomes on preparations obtained with the use of 9-AMA, it is necessary to choose a length interval that must not exceed three average sizes of metaphase chromosomes without the intercalator. The use of 9-AMA increases the resolution of differential C- and OR-banding and the precision of physical chromosome mapping by the FISH method. Of particular importance in studying small chromosomes is optimization of the computer-aided methods used to obtain and process chromosome images. The complex approach developed for analysis of the chromosome organization in plant genomes was used to study the karyotypes of 24 species of the genus Linum L. It permitted their chromosomes to be identified for the first time, and, in addition, B chromosomes were discovered and studied in the karyotypes of the species of the section Syllinum. By similarity of the karyotypes, the studied flax species were distributed in eight groups in agreement with the clusterization of these species according to the results of RAPD analysis performed in parallel. Systematic positions and phylogenetic relationships of the studied flax species were verified. Out results can serve as an important argument in favour of the proposal to develop a special program for sequencing the genome of cultivated flax (L. usitatissimum L.), which is a major representative of small-chromosome species. PMID:20058798

  14. 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.

  15. 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.

  16. Induction of site-specific chromosomal translocations in embryonic stem cells by CRISPR/Cas9

    Science.gov (United States)

    Jiang, Junfeng; Zhang, Li; Zhou, Xingliang; Chen, Xi; Huang, Guanyi; Li, Fengsheng; Wang, Ruizhe; Wu, Nancy; Yan, Youzhen; Tong, Chang; Srivastava, Sankalp; Wang, Yue; Liu, Houqi; Ying, Qi-Long

    2016-01-01

    Chromosomal translocation is the most common form of chromosomal abnormality and is often associated with congenital genetic disorders, infertility, and cancers. The lack of cellular and animal models for chromosomal translocations, however, has hampered our ability to understand the underlying disease mechanisms and to develop new therapies. Here, we show that site-specific chromosomal translocations can be generated in mouse embryonic stem cells (mESCs) via CRISPR/Cas9. Mouse ESCs carrying translocated chromosomes can be isolated and expanded to establish stable cell lines. Furthermore, chimeric mice can be generated by injecting these mESCs into host blastocysts. The establishment of ESC-based cellular and animal models of chromosomal translocation by CRISPR/Cas9 provides a powerful platform for understanding the effect of chromosomal translocation and for the development of new therapeutic strategies. PMID:26898344

  17. 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.

  18. Chromosomal mechanisms in murine radiation acute myeloid leukemogenesis

    International Nuclear Information System (INIS)

    Chromosome 2 abnormalities, particularly interstitial deletions, characterize murine radiation-induced acute myeloid leukaemias (AMLs). Here, G-band analyses in CBA/H mice of early (1-6 month) post 3 Gy X-radiation events in bone marrow cells in vivo and karyotype evolution in one unusual AML are presented. The early event analysis showed that all irradiated animals carry chromosome 2 abnormalities, that chromosome 2 abnormalities are more frequent than expected and that interstitial deletions are more common in chromosome 2 than in the remainder of the genome. On presentation AML case N122 carried a t(2; 11) terminal translocation which, with passaging, evolved into a del2(C3F3). Therefore two pathways in leukaemogenesis might exist, one deletion-driven, the other terminal tranlocation-driven involving interstitial genes and terminal genes respectively of chromosome 2. As all irradiated individuals carried chromosome 2 abnormalities, the formation of these aberrations does not determine individual leukaemogenic sensitivity as only 20-25% of animals would be expected to develop AML. Similar lines of argument suggest that chromosome 2 abnormalities are necessary but not sufficient for radiation leukaemogenesis in CBA/H nor are they rate limiting in leukaemogenesis. (Author)

  19. Chromosomal mechanisms in murine radiation acute myeloid leukemogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Bouffler, S.D.; Breckon, G.; Cox, R. [National Radiological Protection Board, Chilton (United Kingdom)

    1996-04-01

    Chromosome 2 abnormalities, particularly interstitial deletions, characterize murine radiation-induced acute myeloid leukaemias (AMLs). Here, G-band analyses in CBA/H mice of early (1-6 month) post 3 Gy X-radiation events in bone marrow cells in vivo and karyotype evolution in one unusual AML are presented. The early event analysis showed that all irradiated animals carry chromosome 2 abnormalities, that chromosome 2 abnormalities are more frequent than expected and that interstitial deletions are more common in chromosome 2 than in the remainder of the genome. On presentation AML case N122 carried a t(2; 11) terminal translocation which, with passaging, evolved into a del2(C3F3). Therefore two pathways in leukaemogenesis might exist, one deletion-driven, the other terminal tranlocation-driven involving interstitial genes and terminal genes respectively of chromosome 2. As all irradiated individuals carried chromosome 2 abnormalities, the formation of these aberrations does not determine individual leukaemogenic sensitivity as only 20-25% of animals would be expected to develop AML. Similar lines of argument suggest that chromosome 2 abnormalities are necessary but not sufficient for radiation leukaemogenesis in CBA/H nor are they rate limiting in leukaemogenesis. (Author).

  20. Numerical chromosomal instability mediates susceptibility to radiation treatment

    Science.gov (United States)

    Bakhoum, Samuel F.; Kabeche, Lilian; Wood, Matthew D.; Laucius, Christopher D.; Qu, Dian; Laughney, Ashley M.; Reynolds, Gloria E.; Louie, Raymond J.; Phillips, Joanna; Chan, Denise A.; Zaki, Bassem I.; Murnane, John P.; Petritsch, Claudia; Compton, Duane A.

    2015-01-01

    The exquisite sensitivity of mitotic cancer cells to ionizing radiation (IR) underlies an important rationale for the widely used fractionated radiation therapy. However, the mechanism for this cell cycle-dependent vulnerability is unknown. Here we show that treatment with IR leads to mitotic chromosome segregation errors in vivo and long-lasting aneuploidy in tumour-derived cell lines. These mitotic errors generate an abundance of micronuclei that predispose chromosomes to subsequent catastrophic pulverization thereby independently amplifying radiation-induced genome damage. Experimentally suppressing whole-chromosome missegregation reduces downstream chromosomal defects and significantly increases the viability of irradiated mitotic cells. Further, orthotopically transplanted human glioblastoma tumours in which chromosome missegregation rates have been reduced are rendered markedly more resistant to IR, exhibiting diminished markers of cell death in response to treatment. This work identifies a novel mitotic pathway for radiation-induced genome damage, which occurs outside of the primary nucleus and augments chromosomal breaks. This relationship between radiation treatment and whole-chromosome missegregation can be exploited to modulate therapeutic response in a clinically relevant manner. PMID:25606712

  1. Chromosomal translocation involving the beta T cell receptor gene in acute leukemia

    OpenAIRE

    1988-01-01

    DNA spanning a t(7;19) chromosomal translocation breakpoint was isolated from the human T cell line SUP-T7 established from an acute lymphoblastic leukemia. Nucleotide sequence analysis showed that the point of crossover on chromosome 7 occurred immediately adjacent to joining segment J beta 1.1 within the TCR-beta gene, suggesting that this translocation resulted from an error in TCR gene rearrangement. On chromosome 19, the translocation occurred within a previously uncharacterized transcri...

  2. Persistent Increase in Chromosome Instability in Lung Cancer : Possible Indirect Involvement of p53 Inactivation

    OpenAIRE

    Haruki, Nobuhiro; Harano, Tomoko; Masuda, Akira; Kiyono, Tohru; TAKAHASHI, TAKAO; Tatematsu, Yoshio; Shimizu, Shigeki; Mitsudomi, Tetsuya; Konishi, Hiroyuki; Osada, Hirotaka; Fujii, Yoshitaka; Takahashi, Takashi

    2001-01-01

    Karyotype and fluorescence in situ hybridization analyses have demonstrated the frequent presence of an altered static state of the number of chromosomes (ie, aneuploidy) in lung cancer, but it has not been directly established whether aneuploidy is in fact associated with a persistent increase in the rate of chromosomal losses and gains (ie, chromosome instability, or CIN). The study presented here used a panel of 10 lung cancer cell lines to provide for the first time direct evidence that C...

  3. DNA double-strand break repair proteins are required to cap the ends of mammalian chromosomes

    OpenAIRE

    Bailey, Susan M.; Meyne, Julianne; Chen, David J.; Kurimasa, Akihiro; Li, Gloria C.; Lehnert, Bruce E.; Goodwin, Edwin H.

    1999-01-01

    Recent findings intriguingly place DNA double-strand break repair proteins at chromosome ends in yeast, where they help maintain normal telomere length and structure. In the present study, an essential telomere function, the ability to cap and thereby protect chromosomes from end-to-end fusions, was assessed in repair-deficient mouse cell lines. By using fluorescence in situ hybridization with a probe to telomeric DNA, spontaneously occurring chromosome aberrations were examined for telomere ...

  4. 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. PMID:26850366

  5. Complementation of a DNA repair defect in xeroderma pigmentosum cells by transfer of human chromosome 9

    International Nuclear Information System (INIS)

    Complementation of the repair defect in xeroderma pigmentosum cells of complementation group A was achieved by the transfer of human chromosome 9. A set of mouse-human hybrid cell lines, each containing a single Ecogpt-marked human chromosome, was used as a source of donor chromosomes. Chromosome transfer to XPTG-1 cells, a hypoxanthine/guanine phosphoribosyltransferase-deficient mutant of simian virus 40-transformed complementation group A cells, was achieved by microcell fusion and selection for Ecogpt. Chromosome-transfer clones of XPTG-1 cells, each containing a different human donor chromosome, were analyzed for complementation of sensitivity to UV irradiation. Among all the clones, increased levels of resistance to UV was observed only in clones containing chromosome 9. Since our recipient cell line XPTG-1 is hypoxanthine/guanine phosphoribosyltransferase deficient, cultivation of Ecogpt+ clones in medium containing 6-thioguanine permits selection of cells for loss of the marker and, by inference, transferred chromosome 9. Clones isolated for growth in 6-thioguanine, which have lost the Ecogpt-marked chromosome, exhibited a UV-sensitive phenotype, confirming the presence of the repair gene(s) for complementation group A on chromosome 9

  6. 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.

  7. 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.

  8. 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.

  9. 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. PMID:26927960

  10. Folic acid deficiency increases chromosomal instability, chromosome 21 aneuploidy and sensitivity to radiation-induced micronuclei

    International Nuclear Information System (INIS)

    Folic acid deficiency can lead to uracil incorporation into DNA, hypomethylation of DNA, inefficient DNA repair and increase chromosome malsegregation and breakage. Because ionising radiation increases demand for efficient DNA repair and also causes chromosome breaks we hypothesised that folic acid deficiency may increase sensitivity to radiation-induced chromosome breakage. We tested this hypothesis by using the cytokinesis-block micronucleus assay in 10 day WIL2-NS cell cultures at four different folic acid concentrations (0.2, 2, 20, and 200 nM) that span the 'normal' physiological range in humans. The study showed a significant dose-dependent increase in frequency of binucleated cells with micronuclei and/or nucleoplasmic bridges with decreasing folic acid concentration (P < 0.0001, P = 0.028, respectively). These biomarkers of chromosomal instability were also increased in cells irradiated (1.5 Gy γ-rays) on day 9 relative to un-irradiated controls (P < 0.05). Folic acid deficiency and γ-irradiation were shown to have a significant interactive effect on frequency of cells containing micronuclei (two-way ANOVA, interaction P 0.0039) such that the frequency of radiation-induced micronucleated cells (i.e. after subtracting base-line frequency of un-irradiated controls) increased with decreasing folic acid concentration (P-trend < 0.0001). Aneuploidy of chromosome 21, apoptosis and necrosis were increased by folic acid deficiency but not by ionising radiation. The results of this study show that folate status has an important impact on chromosomal stability and is an important modifying factor of cellular sensitivity to radiation-induced genome damage

  11. Selfdual Substitutions in Dimension One

    CERN Document Server

    Berthé, Valérie; Sirvent, Victor

    2011-01-01

    There are several notions of the 'dual' of a word/tile substitution. We show that the most common ones are equivalent for substitutions in dimension one, where we restrict ourselves to the case of two letters/tiles. Furthermore, we obtain necessary and sufficient arithmetic conditions for substitutions being selfdual in this case.

  12. Molecular fundamentals of chromosomal mutagenesis

    International Nuclear Information System (INIS)

    Precise quantitative correlation between the yield of chromosome structure damages and the yield of DNA damages is shown when comparing data on molecular and cytogenetic investigations carried out in cultural Mammalia cells. As the chromosome structure damage is to be connected with the damage of its carcass structure, then it is natural that DNA damage in loop regions is not to affect considerably the structure, while DNA damage lying on the loop base and connected with the chromosome carcass is to play a determining role in chromosomal mutagenesis. This DNA constitutes 1-2% from the total quantity of nuclear DNA. If one accepts that damages of these regions of DNA are ''hot'' points of chromosomal mutagenesis, then it becomes clear why 1-2% of preparation damages in a cell are realized in chromosome structural damages

  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...... 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...... impedance spectroscopy was selected as the sensing method on a microfabricated chip with array of 12 electrode sets. Two independent chips (Chip1 and Chip2) were used for targeting the chromosomal fragments involved in the translocation. Each chip was differentially functionalized with DNA probes matching...

  14. 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.

  15. 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.

  16. Reference-assisted chromosome assembly

    OpenAIRE

    Kim, Jaebum; Larkin, Denis M; Cai, Qingle; Asan,; Zhang, Yongfen; Ge, Ri-Li; Auvil, Loretta; Capitanu, Boris; Zhang, Guojie; Lewin, Harris A.; Ma, Jian

    2013-01-01

    One of the most difficult problems in modern genomics is the assembly of full-length chromosomes using next generation sequencing (NGS) data. To address this problem, we developed “reference-assisted chromosome assembly” (RACA), an algorithm to reliably order and orient sequence scaffolds generated by NGS and assemblers into longer chromosomal fragments using comparative genome information and paired-end reads. Evaluation of results using simulated and real genome assemblies indicates that ou...

  17. Consistency of multidimensional combinatorial substitutions

    CERN Document Server

    Jolivet, Timo

    2011-01-01

    Multidimensional combinatorial substitutions are rules that replace symbols by finite patterns of symbols in Z^d. We focus on the case where the patterns are not necessarily rectangular, which requires a specific description of the way they are glued together in the image by a substitution. Two problems can arise when defining a substitution in such a way: it can fail to be consistent, and the patterns in an image by the substitution might overlap. We prove that it is undecidable whether a two-dimensional substitution is consistent or overlapping, and we provide practical algorithms to decide these properties in some particular cases.

  18. 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…

  19. X-chromosome workshop.

    Science.gov (United States)

    Paterson, A D

    1998-01-01

    Researchers presented results of ongoing research to the X-chromosome workshop of the Fifth World Congress on Psychiatric Genetics, covering a wide range of disorders: X-linked infantile spasms; a complex phenotype associated with deletions of Xp11; male homosexuality; degree of handedness; bipolar affective disorder; schizophrenia; childhood onset psychosis; and autism. This report summarizes the presentations, as well as reviewing previous studies. The focus of this report is on linkage findings for schizophrenia and bipolar disorder from a number of groups. For schizophrenia, low positive lod scores were obtained for markers DXS991 and DXS993 from two studies, although the sharing of alleles was greatest from brother-brother pairs in one study, and sister-sister in the other. Data from the Irish schizophrenia study was also submitted, with no strong evidence for linkage on the X chromosome. For bipolar disease, following the report of a Finnish family linked to Xq24-q27, the Columbia group reported some positive results for this region from 57 families, however, another group found no evidence for linkage to this region. Of interest, is the clustering of low positive linkage results that point to regions for possible further study. PMID:9686435

  20. Chromosome analysis and sorting

    Czech Academy of Sciences Publication Activity Database

    Doležel, Jaroslav; Kubaláková, Marie; Suchánková, Pavla; Kovářová, Pavlína; Bartoš, Jan; Šimková, Hana

    Weinheim : Wiley-VCH, 2007 - (Doležel, J.; Greilhuber, J.; Suda, J.), s. 373-403 ISBN 978-3-527-31487-4 R&D Projects: GA ČR GA521/04/0607; GA ČR GP521/05/P257; GA ČR GD521/05/H013; GA MŠk(CZ) LC06004 Grant ostatní: Mendelova zemědělská a lesnická univerzita v Brně / Agronomická fakulta(CZ) ME 844 Institutional research plan: CEZ:AV0Z5038910 Source of funding: V - iné verejné zdroje ; V - iné verejné zdroje ; V - iné verejné zdroje ; V - iné verejné zdroje ; V - iné verejné zdroje Keywords : Plant flow cytometry * chromosome sorting * flow cytogenetics Subject RIV: EB - Genetics ; Molecular Biology http://books. google .com/books?id=3cwakORieqUC&pg=PA373&lpg=PA373&dq=Chromosome+analysis+and+sorting&source=web&ots=8IyvJlBQyq&sig=_NlXyQQgBCwpj1pTC9YITvvVZqU

  1. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkyl amino substituted triazine amino... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato...

  2. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Science.gov (United States)

    2010-07-01

    ... sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt (generic). 721.2577 Section 721.2577... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted...

  3. Hexavalent chromium induces chromosome instability in human urothelial cells.

    Science.gov (United States)

    Wise, Sandra S; Holmes, Amie L; Liou, Louis; Adam, Rosalyn M; Wise, John Pierce

    2016-04-01

    Numerous metals are well-known human bladder carcinogens. Despite the significant occupational and public health concern of metals and bladder cancer, the carcinogenic mechanisms remain largely unknown. Chromium, in particular, is a metal of concern as incidences of bladder cancer have been found elevated in chromate workers, and there is an increasing concern for patients with metal hip implants. However, the impact of hexavalent chromium (Cr(VI)) on bladder cells has not been studied. We compared chromate toxicity in two bladder cell lines; primary human urothelial cells and hTERT-immortalized human urothelial cells. Cr(VI) induced a concentration- and time-dependent increase in chromosome damage in both cell lines, with the hTERT-immortalized cells exhibiting more chromosome damage than the primary cells. Chronic exposure to Cr(VI) also induced a concentration-dependent increase in aneuploid metaphases in both cell lines which was not observed after a 24h exposure. Aneuploidy induction was higher in the hTERT-immortalized cells. When we correct for uptake, Cr(VI) induces a similar amount of chromosome damage and aneuploidy suggesting that the differences in Cr(VI) sensitivity between the two cells lines were due to differences in uptake. The increase in chromosome instability after chronic chromate treatment suggests this may be a mechanism for chromate-induced bladder cancer, specifically, and may be a mechanism for metal-induced bladder cancer, in general. PMID:26908176

  4. Modifying K sup + /Na sup + discrimination in salt-stressed wheat containing individual chromosomes of a salt-tolerant lophopyrum

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, E.; Dvorak, J.

    1990-01-01

    As outlined in the proposal for this project, the practical or applied impetus for this research is this: salinity of soils and water is inimical to the production of crops and other plants biomass, and to that extent causes a dimunition of the world's capture of solar energy. Of the two strategies of coping with this problem -- rendering soils and water less saline, and developing plants better able to cope with saline substrates -- the present project deals with the latter. The current prolonged drought in California and elsewhere in the West prompts an energetic pursuit of this option, for the availability of less water is tantamount to a general exacerbation of the salinity threat. Bread wheat, Triticum aestivum, is relatively salt-sensitive, whereas tall wheatgrass, Lophopyrum elongatum, is highly salt-tolerant, as shown in our laboratory in investigations going back to the 1960's. In the present investigation both the degree of salt tolerance and that of K{sup +}/Na{sup +} discrimination have been examined in wheat, Triticum aestivum, Chinese Spring,' the wheat x L. elongatum amphiploid, and a set of 20 disomic substitution lines. The latter would reveal which of the L. elongatum chromosomes substituted for their homoeologues in wheat contribute salt tolerance to wheat, and what congruence, if any, exists between that degree of salt tolerance and changes in K{sup +}/Na{sup +} discrimination in the target wheat.

  5. 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.

  6. 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.

  7. 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. PMID:24132905

  8. Preparation and Fluorescent Analysis of Plant Metaphase Chromosomes.

    Science.gov (United States)

    Schwarzacher, Trude

    2016-01-01

    Good preparations are essential for informative analysis of both somatic and meiotic chromosomes, cytogenetics, and cell divisions. Fluorescent chromosome staining allows even small chromosomes to be visualized and counted, showing their morphology. Aneuploidies and polyploidies can be established for species, populations, or individuals while changes occurring in breeding lines during hybridization or tissue culture and transformation protocols can be assessed. The process of division can be followed during mitosis and meiosis including pairing and chiasma distribution, as well as DNA organization and structure during the evolution of chromosomes can be studied. This chapter presents protocols for pretreatment and fixation of material, including tips of how to grow plants to get good and healthy meristem with many divisions. The chromosome preparation technique is described using proteolytic enzymes, but acids can be used instead. Chromosome slide preparations are suitable for fluorochrome staining for fast screening (described in the chapter) or fluorescent in situ hybridization (see Schwarzacher and Heslop-Harrison, In situ hybridization. BIOS Scientific Publishers, Oxford, 2000). PMID:26659956

  9. 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.

  10. Causes of oncogenic chromosomal translocation

    OpenAIRE

    Aplan, Peter D.

    2005-01-01

    Non-random chromosomal translocations are frequently associated with a variety of cancers, especially hematologic malignancies and childhood sarcomas In addition to their diagnostic utility, chromosomal translocations are increasingly being used in the clinic to guide therapeutic decisions. However, the mechanisms which cause these translocations remain poorly understood. Illegit...

  11. Genetics Home Reference: ring chromosome 20 syndrome

    Science.gov (United States)

    ... 3 links) Encyclopedia: Chromosome Encyclopedia: Epilepsy Health Topic: Epilepsy Genetic and Rare Diseases Information Center (1 link) Ring chromosome 20 Additional NIH Resources (2 links) National Human Genome Research Institute: Chromosome Abnormalities National Institute of ...

  12. Genetics Home Reference: ring chromosome 14 syndrome

    Science.gov (United States)

    ... Encyclopedia: Chromosome Health Topic: Developmental Disabilities Health Topic: Epilepsy Genetic and Rare Diseases Information Center (1 link) Ring chromosome 14 Additional NIH Resources (2 links) National Human Genome Research Institute: Chromosome Abnormalities National Institute of ...

  13. 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. PMID:26566111

  14. 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.

  15. ADN et chromosomes

    OpenAIRE

    Hayes, Hélène

    2000-01-01

    Chaque chromosome contient une seule molécule d’ADN. L’ADN déroulé d’un noyau de cellule humaine mesurerait environ 1,8 m : chaque molécule d’ADN est enroulée et compactée en plusieurs étapes, grâce à l’association de différentes protéines, et loge dans le noyau de 6 µm de diamètre. Le degré de condensation de l’ADN est variable selon les régions chromosomiques et les régions les moins condensées sont les plus riches en gènes. L’ADN est composé d’une variété de séquences codantes ou non et ré...

  16. X-Chromosome dosage compensation.

    Science.gov (United States)

    Meyer, Barbara J

    2005-01-01

    In mammals, flies, and worms, sex is determined by distinctive regulatory mechanisms that cause males (XO or XY) and females (XX) to differ in their dose of X chromosomes. In each species, an essential X chromosome-wide process called dosage compensation ensures that somatic cells of either sex express equal levels of X-linked gene products. The strategies used to achieve dosage compensation are diverse, but in all cases, specialized complexes are targeted specifically to the X chromosome(s) of only one sex to regulate transcript levels. In C. elegans, this sex-specific targeting of the dosage compensation complex (DCC) is controlled by the same developmental signal that establishes sex, the ratio of X chromosomes to sets of autosomes (X:A signal). Molecular components of this chromosome counting process have been defined. Following a common step of regulation, sex determination and dosage compensation are controlled by distinct genetic pathways. C. elegans dosage compensation is implemented by a protein complex that binds both X chromosomes of hermaphrodites to reduce transcript levels by one-half. The dosage compensation complex resembles the conserved 13S condensin complex required for both mitotic and meiotic chromosome resolution and condensation, implying the recruitment of ancient proteins to the new task of regulating gene expression. Within each C. elegans somatic cell, one of the DCC components also participates in the separate mitotic/meiotic condensin complex. Other DCC components play pivotal roles in regulating the number and distribution of crossovers during meiosis. The strategy by which C. elegans X chromosomes attract the condensin-like DCC is known. Small, well-dispersed X-recognition elements act as entry sites to recruit the dosage compensation complex and to nucleate spreading of the complex to X regions that lack recruitment sites. In this manner, a repressed chromatin state is spread in cis over short or long distances, thus establishing the

  17. Quantification of the DNA content of structurally abnormal X chromosomes and X chromosome aneuploidy using high resolution bivariate flow karyotyping.

    Science.gov (United States)

    Trask, B; van den Engh, G; Nussbaum, R; Schwartz, C; Gray, J

    1990-01-01

    Quantification of the Hoechst and chromomycin A3 fluorescence intensities of mitotic human chromosomes isolated from karyotypically normal and abnormal cells was performed with a dual beam flow cytometer. The resultant flow karyotypes contain information about the relative DNA content and base composition of chromosomes and their relative frequencies in the mitotic cell sample. The relative copy number of X and Y chromosomes was determined for 38 normal males and females and 6 cell lines with X or Y chromosome aneuploidy. Flow karyotype diagnoses corresponded with conventional cytogenetic results in all cases. We show that chromosome DNA content can be derived from peak position in Hoechst vs. chromomycin flow karyotypes. These values are linearly related to propidium iodide staining intensity as measured with flow cytometry and to the binding of gallocyanin chrome alum to phosphate groups as measured with slide-based scanning photometry. Cell lines with deleted or dicentric X chromosomes ranging in length from 0.53 to 1.95 times normal were analyzed by using flow cytometry. The measured difference in DNA content between a normal X and each of the structurally abnormal chromosomes was linearly correlated to the difference predicted from cytogenetics and/or probe analyses. Deletions of 3-5 Mb, which were at and below the detection limits of conventional cytogenetics, could be quantified by flow karyotyping in individuals with X-linked diseases such as Duchenne muscular dystrophy, choroideremia, and ocular albinism/ichthyosis. The results show that the use of flow karyotyping to quantify the size of restricted regions of the genome can complement conventional cytogenetics and other physical mapping techniques in the study of genetic disorders. PMID:2106419

  18. 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...

  19. 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...

  20. 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

  1. Mitotic chromosome condensation in vertebrates

    International Nuclear Information System (INIS)

    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

  2. How Substitutable Is Natural Capital?

    OpenAIRE

    Markandya, Anil; Pedroso, S.

    2006-01-01

    One of the recurring themes in the sustainability literature has been the legitimacy of using an economic framework to account for natural resources. This paper examines the potential for substituting between different inputs in the generation of income, where the inputs include natural resources such as land and energy resources. A nested constant elasticity of substitution (CES) production function is used to allow flexibility in the estimated elasticities of substitution. Also, with this s...

  3. 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.

  4. Genetic effects of wheat-Haynaldia villosa chromosome T6VS.6AL translo-cation based on advanced sib-line groups%基于高代姊妹系组群研究小麦-簇毛麦染色体 T6 VS .6 AL易位的遗传效应

    Institute of Scientific and Technical Information of China (English)

    别同德; 高德荣; 张晓; 庄丽芳; 赵仁慧; 陈甜甜; 张伯桥

    2015-01-01

    In order to elucidate the genetic effects of wheat⁃Haynaldia villosa chromosome T6VS.6AL translocation for its application in wheat breeding, advanced sib⁃lines derived from the primitive seeds of Yangmai18 for variety regional test, were grouped according to powdery mildew resistance. Comparison between the resistant and susceptible groups was performed on major agronomic and quality traits. The results showed that T6VS.6AL has significantly positive effects on kernel weight, plant height, and spike length at the 0�01 level. It has significantly positive effect on spikelet number per spike and negative effect on spikelet density, at the 0.05 and 0.01 levels, respectively. It has no significant effect on kernel number per plant, kernel number per spike, tiller number per plant, and yield. Furthermore, T6VS.6AL has no effect on wheat quality general⁃ly. Based on the above results, it is concluded that sib line groups are valuable materials for precisely evaluating genetic effects of a certain chromosomal segment. Dwanf or medium⁃height stem, high⁃yielding and widely adaptable wheat varieties carrying translocated chromosome T6VS. 6AL are suggested to be used as the last recurrent parent during roll⁃ing convergent backcross.%为了解小麦⁃簇毛麦抗白粉病易位染色体T6VS.6AL的遗传效应以更好地将其用于小麦品种选育,对扬麦18原始区域试验种子衍生的抗白粉病姊妹系、感白粉病姊妹系组群进行主要农艺和品质性状的比较。结果表明:T6VS.6AL易位对小麦的千粒质量、株高和穗长有极显著正向效应,对每穗小穗数呈显著正向效应,对小穗密度呈极显著负向效应,对单株总粒数、每穗粒数、单株穗数、株系产量没有显著影响;T6VS.6AL易位总体上对小麦品质没有影响。综上所述,高代姊妹系组群是准确评价特定染色体区段遗传效应的宝贵材料,在利用T6VS.6AL易位系进行滚

  5. Rapid De Novo Evolution of X Chromosome Dosage Compensation in Silene latifolia, a Plant with Young Sex Chromosomes

    Science.gov (United States)

    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. PMID:22529744

  6. Substitute Valuations: Generation and Structure

    CERN Document Server

    Hajek, Bruce

    2007-01-01

    Substitute valuations (in some contexts called gross substitute valuations) are prominent in combinatorial auction theory. An algorithm is given in this paper for generating a substitute valuation through Monte Carlo simulation. In addition, the geometry of the set of all substitute valuations for a fixed number of goods K is investigated. The set consists of a union of polyhedrons, and the maximal polyhedrons are identified for K=4. It is shown that the maximum dimension of the maximal polyhedrons increases with K nearly as fast as two to the power K.

  7. Irradiation induced wheat-alien translocation lines and their application in wheat breeding

    International Nuclear Information System (INIS)

    Wild relatives are rich gene resources for wheat improvement. Transfer of alien useful genes to wheat through development of wheat-alien translocations, especially small alien segment translocations, is important for wheat breeding. Wheat-alien genetic stocks such as amphiploid, addition or substitution lines were irradiated for translocation induction. Mature male or female gametes before flowering on the spikes were irradiated by 60Co-γ-rays at doses ranged from 8 to 22.4Gy. Chromosome C-banding and genomic in situ hybridization (GISH) were used to identify chromosome translocation. Backcross of M1 plants using normal fresh pollen of common wheat was employed to enhance the transmission rate of various structural changes in their progenies. The results showed that the dose of 8∼12Gy was suitable for pollen irradiation while 15∼20Gy was suitable for female-gamete irradiation. Irradiation treatment just before gamete maturation is advantageous to acquisition of more M1 hybrids with high frequency of chromosome structural variation. The frequency of plants with at least one translocation chromosome in M1 could be increased up to 70% through pollen irradiation of Triticum durum-Haynaldia villosa amphiploid. More than one hundred translocated chromosomes have been identified in the BC1 and BC2. 57 terminal and 80 intercalary translocations with small alien chromosome segments were induced through female-gamete irradiation conducted on T.aestivum-H.villosa 6VS/6AL translocation line. For the 22.4Gy dosage treatment, the induction frequencies of interstitial translocation, terminal translocation and deletion were 21.02%, 14.01%, and 14.65%, respectively, which were much higher than that previously reported. These genetic stocks will be useful for physical mapping of alien genes such as Pm21. Some compensate translocations conveying useful agronomic traits would be useful in wheat breeding. The T.aestivum-H.villosa 6VS/6AL translocation has been used in wheat

  8. 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

    2013-01-01

    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. PMID:23884766

  9. Whole-Genome and Chromosome Evolution Associated with Host Adaptation and Speciation of the Wheat Pathogen Mycosphaerella graminicola

    Science.gov (United States)

    Stukenbrock, Eva H.; Jørgensen, Frank G.; Zala, Marcello; Hansen, Troels T.; McDonald, Bruce A.; Schierup, Mikkel H.

    2010-01-01

    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 accompanied by structural

  10. 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

    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

  11. Chromosome conservation in squamate reptiles revealed by comparative chromosome painting

    Czech Academy of Sciences Publication Activity Database

    Giovannotti, M.; Pokorná, Martina; Kratochvíl, L.; Caputo, V.; Olmo, E.; Ferguson-Smith, M. A.; Rens, W.

    Manchester : ICCS, 2011. 78-78. [Intarnational Chromosome Conference /18./. 29.08.2011-02.09.2011, Manchester] Institutional research plan: CEZ:AV0Z50450515 Keywords : squamate reptiles Subject RIV: EG - Zoology

  12. Numerous transitions of sex chromosomes in Diptera.

    Directory of Open Access Journals (Sweden)

    Beatriz Vicoso

    2015-04-01

    Full Text Available 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.

  13. 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.

  14. Familial transmission of a deletion of chromosome 21 derived from a translocation between chromosome 21 and an inverted chromosome 22.

    Science.gov (United States)

    Aviv, H; Lieber, C; Yenamandra, A; Desposito, F

    1997-06-27

    Chromosome analysis of a newborn boy with Down syndrome resulted in the identification of a family with an unusual derivative chromosome 22. The child has 46 chromosomes, including two chromosomes 21, one normal chromosome 22, and a derivative chromosome 22. Giemsa banding and fluorescent in situ hybridization (FISH) studies show that the derivative chromosome is chromosome 22 with evidence of both paracentric and pericentric inversions, joined to the long arm of chromosome 21 from 21q21.2 to qter. The rearrangement results in partial trisomy 21 extending from 21q21.2 to 21q terminus in the patient. The child's mother, brother, maternal aunt, and maternal grandmother are all carriers of the derivative chromosome. All have 45 chromosomes, with one normal chromosome 21, one normal chromosome 22, and the derivative chromosome 22. The rearrangement results in the absence of the short arm, the centromere, and the proximal long arm of chromosome 21 (del 21pter-21q21.2) in carriers. Carriers of the derivative chromosome in this family have normal physical appearance, mild learning disabilities and poor social adjustment. PMID:9182781

  15. Meiosis and chromosome painting of sex chromosome systems in Ceboidea.

    Science.gov (United States)

    Mudry, M D; Rahn, I M; Solari, A J

    2001-06-01

    The identity of the chromosomes involved in the multiple sex system of Alouatta caraya (Aca) and the possible distribution of this system among other Ceboidea were investigated by chromosome painting of mitotic cells from five species and by analysis of meiosis at pachytene in two species. The identity of the autosome #7 (X2) involved in the multiple system of Aca and its breakage points were demonstrated by both meiosis and chromosome painting. These features are identical to those described by Consigliere et al. [1996] in Alouatta seniculus sara (Assa) and Alouatta seniculus arctoidea (Asar). This multiple system was absent in the other four Ceboidea species studied here. However, data from the literature strongly suggest the presence of this multiple in other members of this genus. The presence of this multiple system among several species and subspecies that show high levels of chromosome rearrangements may suggest a special selective value of this multiple. The meiotic features of the sex systems of Aca and Cebus apella paraguayanus (Cap) are strikingly different at pachytene, as the latter system is similar to the sex pair of man and other primates. The relatively large genetic distances between species presently showing this multiple system suggest that its origin is not recent. Other members of the same genus should be investigated at meiosis and by chromosome painting in order to know the extent and distribution of this complex sex-chromosome system. PMID:11376445

  16. Chromosomal localization of the human gene encoding c-myc promoter-binding protein (MPB1) to chromosome 1p35-pter

    Energy Technology Data Exchange (ETDEWEB)

    White, R.A.; Dowler, L.L. [Univ. of Missouri, Kansas City, MO (United States); Adkison, L.R. [Mercer Univ. School of Medicine, Macon, GA (United States); Ray, R.B. [St. Louis Univ. Health Sciences Center, St. Louis, MO (United States)

    1997-02-01

    We report the mapping of the human gene MPB1 (c-myc promoter binding protein), a recently identified gene regulatory protein. MPB1 binds to the c-myc P2 promoter and exerts a negative regulatory role on c-myc transcription. Since exogenous expression from transfection of the MPB1 gene suppresses the tumorigenic property of breast cancer cells, there was interest in determining the chromosomal location of this gene. The human MPB1 gene was assigned to human chromosome 1p35-pter using Southern blot analyses of genomic DNAs from rodent-human somatic hybrid cell lines. A specific human genomic fragment was observed only in the somatic cell lines containing human chromosome 1 or the p35-pter region of the chromosome. 10 refs., 2 figs.

  17. Enhancement of aluminum tolerance in wheat by addition of chromosomes from the wild relative Leymus racemosus.

    Science.gov (United States)

    Mohammed, Yasir Serag Alnor; Eltayeb, Amin Elsadig; Tsujimoto, Hisashi

    2013-12-01

    Aluminum (Al) toxicity is the key factor limiting wheat production in acid soils. Soil liming has been used widely to increase the soil pH, but due to its high cost, breeding tolerant cultivars is more cost-effective mean to mitigate the problem. Tolerant cultivars could be developed by traditional breeding, genetic transformation or introgression of genes from wild relatives. We used 30 wheat alien chromosome addition lines to identify new genetic resources to improve wheat tolerance to Al and to identify the chromosomes harboring the tolerance genes. We evaluated these lines and their wheat background Chinese Spring for Al tolerance in hydroponic culture at various Al concentrations. We also investigated Al uptake, oxidative stress and cell membrane integrity. The L. racemosus chromosomes A and E significantly enhanced the Al tolerance of the wheat in term of relative root growth. At the highest Al concentration tested (200 μM), line E had the greatest tolerance. The introgressed chromosomes did not affect Al uptake of the tolerant lines. We attribute the improved tolerance conferred by chromosome E to improved cell membrane integrity. Chromosome engineering with these two lines could produce Al-tolerant wheat cultivars. PMID:24399913

  18. 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…

  19. No neocentric activity on Aegilops markgrafii chromosome E.

    Science.gov (United States)

    Schubert, V

    2011-01-01

    Classical neocentromeres, proven mainly in Poaceae species, cause meiotic drive in higher plants. Here I present data indicating that the morphological stretching of a chromatin domain at the long arm of Aegilops markgrafii chromosome E during meiosis is not due to a supposed neocentric activity. The stretching is visible at the alien univalent in metaphase I and anaphase I pollen mother cells of Triticum aestivum--Ae. markgrafii monosomic addition line E and at one univalent of the 49-chromosome-containing plants containing the haploid Ae. markgrafii genome added to wheat. The absence of both centromeric histone variant CENH3 and attachment of spindle fibers, proven by immunostaining with antibodies against CENH3 and tubulin, respectively, revealed that the univalent elongation of chromosome E is not caused by a classical plant neocentromere. PMID:20720397

  20. 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.

  1. Multitude multicolor chromosome banding (mMCB) - a comprehensive one-step multicolor FISH banding method.

    Science.gov (United States)

    Weise, A; Heller, A; Starke, H; Mrasek, K; Kuechler, A; Pool-Zobel, B L; Claussen, U; Liehr, T

    2003-01-01

    Multicolor chromosome banding (MCB) using one single chromosome-specific MCB probe set per experiment was previously reported as powerful tool in molecular cytogenetics for the characterization of all kinds of human marker chromosomes. However, a quick analysis of karyotypes with highly complex chromosomal changes was hampered by the problem that up to 24 MCB experiments were necessary for a comprehensive karyotype description. To overcome that limitation the 138 available region-specific microdissection-derived libraries for all human chromosomes were combined to one single probe set, called multitude MCB (mMCB). A typical fluorescence banding pattern along the human karyotype is produced, which can be evaluated either by transforming these profiles into chromosome region-specific pseudo-colors or more reliably by studying the fluorescence profiles. The mMCB probe set has been applied on chromosomes of normal male and female probands, two primary myelodysplastic syndromes and two solid tumor cell lines. Additionally, a cell line of Gorilla gorilla (GGO) studied previously by single chromosome-specific MCB was reevaluated by the mMCB method. All results were in concordance with those obtained in parallel or by other cytogenetic and molecular cytogenetic approaches indicating that mMCB is a powerful multicolor FISH banding tool for fast characterization of complex karyotypes. PMID:15004461

  2. Methods for chromosome-specific staining

    Science.gov (United States)

    Gray, Joe W.; Pinkel, Daniel

    1995-01-01

    Methods and compositions for chromosome-specific staining are provided. Compositions comprise heterogenous mixtures of labeled nucleic acid fragments having substantially complementary base sequences to unique sequence regions of the chromosomal DNA for which their associated staining reagent is specific. Methods include methods for making the chromosome-specific staining compositions of the invention, and methods for applying the staining compositions to chromosomes.

  3. Chromosome Architecture and Genome Organization

    OpenAIRE

    Giorgio Bernardi

    2015-01-01

    How the same DNA sequences can function in the three-dimensional architecture of interphase nucleus, fold in the very compact structure of metaphase chromosomes and go precisely back to the original interphase architecture in the following cell cycle remains an unresolved question to this day. The strategy used to address this issue was to analyze the correlations between chromosome architecture and the compositional patterns of DNA sequences spanning a size range from a few hundreds to a few...

  4. Chromosome evolution in Neotropical butterflies

    OpenAIRE

    Saura, Anssi; Von Schoultz, Barbara; Saura, Anja O.; Brown, Keith S., Jr.

    2013-01-01

    We list the chromosome numbers for 65 species of Neotropical Hesperiidae and 104 species or subspecies of Pieridae. In Hesperiidae the tribe Pyrrhopygini have a modal n = 28, Eudaminae and Pyrgini a modal n = 31, while Hesperiinae have n = around 29. Among Pieridae, Coliadinae have a strong modal n = 31 and among Pierinae Anthocharidini are almost fixed for n = 15 while Pierini vary with n = 26 as the most common chromosome number. Dismorphiinae show wide variation. We discuss these results i...

  5. Efficiency of Xist-mediated silencing on autosomes is linked to chromosomal domain organisation

    Directory of Open Access Journals (Sweden)

    Tang Y Amy

    2010-05-01

    Full Text Available Abstract Background X chromosome inactivation, the mechanism used by mammals to equalise dosage of X-linked genes in XX females relative to XY males, is triggered by chromosome-wide localisation of a cis-acting non-coding RNA, Xist. The mechanism of Xist RNA spreading and Xist-dependent silencing is poorly understood. A large body of evidence indicates that silencing is more efficient on the X chromosome than on autosomes, leading to the idea that the X chromosome has acquired sequences that facilitate propagation of silencing. LINE-1 (L1 repeats are relatively enriched on the X chromosome and have been proposed as candidates for these sequences. To determine the requirements for efficient silencing we have analysed the relationship of chromosome features, including L1 repeats, and the extent of silencing in cell lines carrying inducible Xist transgenes located on one of three different autosomes. Results Our results show that the organisation of the chromosome into large gene-rich and L1-rich domains is a key determinant of silencing efficiency. Specifically genes located in large gene-rich domains with low L1 density are relatively resistant to Xist-mediated silencing whereas genes located in gene-poor domains with high L1 density are silenced more efficiently. These effects are observed shortly after induction of Xist RNA expression, suggesting that chromosomal domain organisation influences establishment rather than long-term maintenance of silencing. The X chromosome and some autosomes have only small gene-rich L1-depleted domains and we suggest that this could confer the capacity for relatively efficient chromosome-wide silencing. Conclusions This study provides insight into the requirements for efficient Xist mediated silencing and specifically identifies organisation of the chromosome into gene-rich L1-depleted and gene-poor L1-dense domains as a major influence on the ability of Xist-mediated silencing to be propagated in a continuous

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

    Science.gov (United States)

    Gruber, Simone Lilian; Diniz, Débora; Sobrinho-Scudeler, Patrícia Elda; Fausto Foresti; Haddad, Célio Fernando Baptista; Kasahara, Sanae

    2014-01-01

    Abstract 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. PMID:25349670

  7. 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.

  8. 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.

  9. Chromosome evolution in Neotropical butterflies.

    Science.gov (United States)

    Saura, Anssi; Von Schoultz, Barbara; Saura, Anja O; Brown, Keith S

    2013-06-01

    We list the chromosome numbers for 65 species of Neotropical Hesperiidae and 104 species or subspecies of Pieridae. In Hesperiidae the tribe Pyrrhopygini have a modal n = 28, Eudaminae and Pyrgini a modal n = 31, while Hesperiinae have n = around 29. Among Pieridae, Coliadinae have a strong modal n = 31 and among Pierinae Anthocharidini are almost fixed for n = 15 while Pierini vary with n = 26 as the most common chromosome number. Dismorphiinae show wide variation. We discuss these results in the context of chromosome numbers of over 1400 Neotropical butterfly species and subspecies derived from about 3000 populations published here and in earlier papers of a series. The overall results show that many Neotropical groups are characterized by karyotype instability with several derived modal numbers or none at all, while almost all taxa of Lepidoptera studied from the other parts of the world have one of n = 29-31 as modal numbers. Possibly chromosome number changes become fixed in the course of speciation driven by biotic interactions. Population subdivision and structuring facilitate karyotype change. Factors that stabilize chromosome numbers include hybridization among species sharing the same number, migration, sexual selection and possibly the distribution of chromosomes within the nucleus. PMID:23865963

  10. Chromosome Architecture and Genome Organization

    Science.gov (United States)

    Bernardi, Giorgio

    2015-01-01

    How the same DNA sequences can function in the three-dimensional architecture of interphase nucleus, fold in the very compact structure of metaphase chromosomes and go precisely back to the original interphase architecture in the following cell cycle remains an unresolved question to this day. The strategy used to address this issue was to analyze the correlations between chromosome architecture and the compositional patterns of DNA sequences spanning a size range from a few hundreds to a few thousands Kilobases. This is a critical range that encompasses isochores, interphase chromatin domains and boundaries, and chromosomal bands. The solution rests on the following key points: 1) the transition from the looped domains and sub-domains of interphase chromatin to the 30-nm fiber loops of early prophase chromosomes goes through the unfolding into an extended chromatin structure (probably a 10-nm “beads-on-a-string” structure); 2) the architectural proteins of interphase chromatin, such as CTCF and cohesin sub-units, are retained in mitosis and are part of the discontinuous protein scaffold of mitotic chromosomes; 3) the conservation of the link between architectural proteins and their binding sites on DNA through the cell cycle explains the “mitotic memory” of interphase architecture and the reversibility of the interphase to mitosis process. The results presented here also lead to a general conclusion which concerns the existence of correlations between the isochore organization of the genome and the architecture of chromosomes from interphase to metaphase. PMID:26619076

  11. Patterns of molecular evolution of an avian neo-sex chromosome.

    Science.gov (United States)

    Pala, Irene; Hasselquist, Dennis; Bensch, Staffan; Hansson, Bengt

    2012-12-01

    Newer parts of sex chromosomes, neo-sex chromosomes, offer unique possibilities for studying gene degeneration and sequence evolution in response to loss of recombination and population size decrease. We have recently described a neo-sex chromosome system in Sylvioidea passerines that has resulted from a fusion between the first half (10 Mb) of chromosome 4a and the ancestral sex chromosomes. In this study, we report the results of molecular analyses of neo-Z and neo-W gametologs and intronic parts of neo-Z and autosomal genes on the second half of chromosome 4a in three species within different Sylvioidea lineages (Acrocephalidea, Timaliidae, and Alaudidae). In line with hypotheses of neo-sex chromosome evolution, we observe 1) lower genetic diversity of neo-Z genes compared with autosomal genes, 2) moderate synonymous and weak nonsynonymous sequence divergence between neo-Z and neo-W gametologs, and 3) lower GC content on neo-W than neo-Z gametologs. Phylogenetic reconstruction of eight neo-Z and neo-W gametologs suggests that recombination continued after the split of Alaudidae from the rest of the Sylvioidea lineages (i.e., after ~42.2 Ma) and with some exceptions also after the split of Acrocephalidea and Timaliidae (i.e., after ~39.4 Ma). The Sylvioidea neo-sex chromosome shares classical evolutionary features with the ancestral sex chromosomes but, as expected from its more recent origin, shows weaker divergence between gametologs. PMID:22826461

  12. Flow analysis of human chromosome sets by means of mixing-stirring device

    Science.gov (United States)

    Zenin, Valeri V.; Aksenov, Nicolay D.; Shatrova, Alla N.; Klopov, Nicolay V.; Cram, L. Scott; Poletaev, Andrey I.

    1997-05-01

    A new mixing and stirring device (MSD) was used to perform flow karyotype analysis of single human mitotic chromosomes analyzed so as to maintain the identity of chromosomes derived from the same cell. An improved method for cell preparation and intracellular staining of chromosomes was developed. The method includes enzyme treatment, incubation with saponin and separation of prestained cells from debris on a sucrose gradient. Mitotic cells are injected one by one in the MSD which is located inside the flow chamber where cells are ruptured, thereby releasing chromosomes. The set of chromosomes proceeds to flow in single file fashion to the point of analysis. The device works in a stepwise manner. The concentration of cells in the sample must be kept low to ensure that only one cell at a time enters the breaking chamber. Time-gated accumulation of data in listmode files makes it possible to separate chromosome sets comprising of single cells. The software that was developed classifies chromosome sets according to different criteria: total number of chromosomes, overall DNA content in the set, and the number of chromosomes of certain types. This approach combines the high performance of flow cytometry with the advantages of image analysis. Examples obtained with different human cell lines are presented.

  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. X-ray induction of mitotic and meiotic chromosome aberrations

    International Nuclear Information System (INIS)

    In 1964 six pairs of rat kangaroo (Potorous tridactylis) were obtained from Australia. The tissues of these animals were used to initiate cell lines. Since this species has a low chromosome number of six pairs, each pair with its own distinctive morphology, it is particularly favorable for cytogenetic research. In cell cultures derived from the corneal endothelial tissues of one animal there emerged a number of haploid cells. The number of haploid cells in the cultures reached as high as 20% of the total mitotic configurations. The in vitro diploid and haploid mixture cell cultures could be a resemblance or a coincidence to the mixture existence of the diploid primary spermatocytes and the haploid secondary spermatocytes (gametes) in the in vivo testicular tissues of the male animals. It would be interesting to compare reactions of the haploid and diploid cell mixture, either in the cultures or in the testes, to x-ray exposure. Two other studies involving x-ray effects on Chinese hamster oocyte maturation and meiotic chromosomes and the x-ray induction of Chinese hamster spermatocyte meiotic chromosome aberrations have been done in this laboratory. A review of these three studies involving diploid and haploid chromosomes may lead to further research in the x-ray induction of chromosome aberrations

  15. Radiation-induced chromosomal instability in human mammary epithelial cells

    Science.gov (United States)

    Durante, M.; Grossi, G. F.; Yang, T. C.

    1996-01-01

    Karyotypes of human cells surviving X- and alpha-irradiation have been studied. Human mammary epithelial cells of the immortal, non-tumorigenic cell line H184B5 F5-1 M/10 were irradiated and surviving clones isolated and expanded in culture. Cytogenetic analysis was performed using dedicated software with an image analyzer. We have found that both high- and low-LET radiation induced chromosomal instability in long-term cultures, but with different characteristics. Complex chromosomal rearrangements were observed after X-rays, while chromosome loss predominated after alpha-particles. Deletions were observed in both cases. In clones derived from cells exposed to alpha-particles, some cells showed extensive chromosome breaking and double minutes. Genomic instability was correlated to delayed reproductive death and neoplastic transformation. These results indicate that chromosomal instability is a radiation-quality-dependent effect which could determine late genetic effects, and should therefore be carefully considered in the evaluation of risk for space missions.

  16. 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.

  17. Evolution of Sex Chromosomes in Insects

    OpenAIRE

    Kaiser, Vera B; Bachtrog, Doris

    2010-01-01

    Sex chromosomes have many unusual features relative to autosomes. Y (or W) chromosomes lack genetic recombination, are male- (female-) limited, and show an abundance of genetically inert heterochromatic DNA but contain few functional genes. X (or Z) chromosomes also show sex-biased transmission (i.e., X chromosomes show female-biased and Z-chromosomes show male-biased inheritance) and are hemizygous in the heterogametic sex. Their unusual ploidy level and pattern of inheritance imply that sex...

  18. Detailed analysis of X chromosome inactivation in a 49,XXXXX pentasomy

    Science.gov (United States)

    Moraes, Lucia M; Cardoso, Leila CA; Moura, Vera LS; Moreira, Miguel AM; Menezes, Albert N; Llerena, Juan C; Seuánez, Héctor N

    2009-01-01

    Background Pentasomy X (49,XXXXX) has been associated with a severe clinical condition, presumably resulting from failure or disruption of X chromosome inactivation. Here we report that some human X chromosomes from a patient with 49,XXXXX pentasomy were functionally active following isolation in inter-specific (human-rodent) cell hybrids. A comparison with cytogenetic and molecular findings provided evidence that more than one active X chromosome was likely to be present in the cells of this patient, accounting for her abnormal phenotype. Results 5-bromodeoxyuridine (BrdU)-pulsed cultures showed different patterns among late replicating X chromosomes suggesting that their replication was asynchronic and likely to result in irregular inactivation. Genotyping of the proband and her mother identified four maternal and one paternal X chromosomes in the proband. It also identified the paternal X chromosome haplotype (P), indicating that origin of this X pentasomy resulted from two maternal, meiotic non-disjunctions. Analysis of the HUMANDREC region of the androgen receptor (AR) gene in the patient's mother showed a skewed inactivation pattern, while a similar analysis in the proband showed an active paternal X chromosome and preferentially inactivated X chromosomes carrying the 173 AR allele. Analyses of 33 cell hybrid cell lines selected in medium containing hypoxanthine, aminopterin and thymidine (HAT) allowed for the identification of three maternal X haplotypes (M1, M2 and MR) and showed that X chromosomes with the M1, M2 and P haplotypes were functionally active. In 27 cell hybrids in which more than one X haplotype were detected, analysis of X inactivation patterns provided evidence of preferential inactivation. Conclusion Our findings indicated that 12% of X chromosomes with the M1 haplotype, 43.5% of X chromosomes with the M2 haplotype, and 100% of the paternal X chromosome (with the P haplotype) were likely to be functionally active in the proband's cells, a

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

    International Nuclear Information System (INIS)

    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)

  20. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted phenyl azo substituted... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  1. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted phenyl azo substituted... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  2. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted phenyl azo substituted... Significant New Uses for Specific Chemical Substances § 721.3063 Substituted phenyl azo substituted phenyl... chemical substances identified generically as substituted phenyl azo substituted phenyl esters (PMNs...

  3. Phenolic content variability and its chromosome location in tritordeum

    Directory of Open Access Journals (Sweden)

    Fernando ePistón

    2014-01-01

    Full Text Available For humans, wheat is the most important source of calories, but it is also a source of antioxidant compounds that are involved in the prevention of chronic disease. Among the antioxidant compounds, phenolic acids have great potential to improve human health. In this paper we evaluate the effect of environmental and genetic factors on the phenolic content in the grain of a collection of tritordeums with different cytoplasm and chromosome substitutions. To this purpose, tritordeum flour was used for extraction of the free, conjugates and bound phenolic compounds. These phenolic compounds were identified and quantified by RP-HPLC and the results were analyzed by univariate and multivariate methods. This is the first study that describes the composition of phenolic acids of the amphiploid tritordeum. As in wheat, the predominant phenolic compound is ferulic acid. In tritordeum there is great variability for the content of phenolic compounds and the main factor which determines its content is the genotype followed by the environment, in this case include in the year factor. Phenolic acid content is associated with the substitution of chromosome DS1D(1H$^{ch}$ and DS2D(2H$^{ch}$, and the translocation 1RS/1BL in tritordeum. The results show that there is high potential for further improving the quality and quantity of phenolics in tritordeum because this amphiploid shows high variability for the content of phenolic compounds.

  4. Retrospective dosimetry using chromosome painting

    International Nuclear Information System (INIS)

    Chromosome aberration frequency measured in peripheral lymphocytes of persons exposed to ionizing radiation has been used since 1960s for dose assessment. Suspected overexposure is usually evaluated by the frequency of dicentrics and centric rings using an appropriate in vitro calibration curve. However, these chromosome aberrations are unstable with time after exposure and dose reconstruction may encounter uncertainties when the time between the exposure and the analysis is considerable or even unknown. It appears that translocations persist with time after exposure and may be used as an indication of acute past overexposures. Moreover, they appear to accumulate the cytogenetical information, which correlates with the dose received under fractionated, chronic or even occupational exposure conditions. Translocations may be detected using G-banding, which allows to score the total amount of radiation induced translocations but it is a time consuming method, or by Chromosome Painting, a method base on the Fluorescence in situ Hybridization (FISH) technique, painting only some chromosome pairs with specific whole chromosome probes and then extrapolating the observed translocation frequencies to the full genome. The latter method allows a faster aberration scoring than G-banding and appears to be the most promissory tool for biodosimetry, particularly when it is necessary to assess low doses and consequently to score a large number of metaphases, e.g. radiation workers exposed within dose limits. As with the unstable chromosome aberration, it is necessary an in vitro calibration curve based on the frequency of stable chromosome aberrations to assess doses. Our laboratory performed calibration curves for Co60 γ-rays based on the frequencies of unstable (dicentrics and centric rings detected by conventional Giemsa staining) and stable chromosome aberrations (translocations and inversions, detected by G-banding). In order to minimize the interlaboratory variability, we

  5. 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 ...

  6. 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.

  7. Radiation-induced chromosomal instability

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, S. [GSI, Biophysics, Darmstadt (Germany)

    1999-03-01

    Recent studies on radiation-induced chromosomal instability in the progeny of exposed mammalian cells were briefly described as well as other related studies. For the analysis of chromosomal damage in clones, cells were seeded directly after exposure in cell well-dish to form single cell clones and post-irradiation chromosome aberrations were scored. Both exposure to isoeffective doses of X-ray or 270 MeV/u C-ions (13 keV/{mu}m) increased the number of clones with abnormal karyotype and the increase was similar for X-ray and for C-ions. Meanwhile, in the progeny of cells for mass cultures, there was no indication of a delayed expression of chromosomal damage up to 40 population doublings after the exposure. A high number of aberrant cells were only observed directly after exposure to 10.7 MeV/u O-ions, i.e. in the first cycle cells and decreased with subsequent cell divisions. The reason for these differences in the radiation-induced chromosomal instability between clonal isolates and mass culture has not been clarified. Recent studies indicated that genomic instability occurs at a high frequency in the progeny of cells irradiated with both sparsely and densely ionizing radiation. Such genomic instability is thought likely to increase the risk of carcinogenesis, but more data are required for a well understanding of the health risks resulting from radiation-induced delayed instability. (M.N.)

  8. 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.

  9. Simple, heart-smart substitutions

    Science.gov (United States)

    ... fat and cholesterol . It also limits salt, refined sugar, and processed foods. Making heart-healthy food choices does not mean you have to sacrifice flavor. The key is to substitute less healthy foods with fresh produce, whole grains, ...

  10. NMR a substitute for CT

    International Nuclear Information System (INIS)

    The possibility that NMR (Nuclear Magnetic Resonance) can be a substitute for CT (Computerized Tomography), is described. NMR focus on the nuclei in the atoms of certain elements, for example hydrogen

  11. Chromosomal rearrangement interferes with meiotic X chromosome inactivation

    Czech Academy of Sciences Publication Activity Database

    Homolka, David; Ivánek, Robert; Čapková, Jana; Jansa, Petr; Forejt, Jiří

    2007-01-01

    Roč. 17, č. 10 (2007), s. 1431-1437. ISSN 1088-9051 R&D Projects: GA MŠk(CZ) 1M0520; GA ČR GA301/06/1334; GA ČR GA301/07/1383 Grant ostatní: Howard Hughes Medical Institute(US) HHMI 55000306 Institutional research plan: CEZ:AV0Z50520514 Keywords : chromosomal translocations * meiotic X chromosome inactivation * spermatogenesis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 11.224, year: 2007

  12. Testing Substitutability of Weak Preferences

    OpenAIRE

    Aziz, Haris; Brill, Markus; Harrenstein, Paul

    2012-01-01

    In many-to-many matching models, substitutable preferences constitute the largest domain for which a pairwise stable matching is guaranteed to exist. In this note, we extend the recently proposed algorithm of Hatfield et al. [3] to test substitutability of weak preferences. Interestingly, the algorithm is faster than the algorithm of Hatfield et al. by a linear factor on the domain of strict preferences.

  13. Amalgam substitutes: a critical analysis

    OpenAIRE

    Lutz, Felix; Krejci, Ivo

    2000-01-01

    Quality standards for restorations recently have been defined in Switzerland. Amalgam substitutes must meet restoration Grade 2 requirements (i.e., pulp and dental hard substance must be preserved, and both form and function of the tooth have to be reconstituted). The pertinent operative technique has to be simple and amalgam-like. A minimum service life of 8 years is required. This in vitro study investigated the clinical potential of several amalgam substitutes, taking into account the oper...

  14. Point substitutions in Japanese alloalbumins.

    OpenAIRE

    Arai, K.; Madison, J; Huss, K; Ishioka, N; Satoh, C; Fujita, M.; Neel, J. V.; Sakurabayashi, I; Putnam, F W

    1989-01-01

    We have completed the structural study of five rare types of inherited albumin variants (alloalbumins) discovered in the Biochemical Genetics Study of 15,581 unrelated children in Hiroshima and Nagasaki. We have also identified the structural change in five other alloalbumin specimens detected during clinical electrophoresis of sera from Japanese living near Tokyo. Each of the five albumin variants from Nagasaki and Hiroshima has a single amino acid substitution. All of these substitutions di...

  15. 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.

  16. A Dysmorphic Child with a Pericentric Inversion of Chromosome 8

    OpenAIRE

    Venkateshwari Ananthapur; Srilekha Avvari; Sujatha Madireddi; Pratibha Nallari; Jyothy Akka

    2012-01-01

    An 8-year-old boy was referred to our institute with dysmorphic features such as mild lupus, micrognathia, low hair line, hypoplasia, hemi atrophy of left side of the face, abnormal size of ears, hypothenar, hypoplasia of chin, and tongue tie. MRI scan was found to be normal and EEG suggestive of generalized seizure disorder. Cytogenetic evaluation of the proband revealed a pericentric inversion of chromosome 8 with 46, XY, and inv 8 (p11.2; q21.2) karyotype.

  17. Escape Artists of the X Chromosome.

    Science.gov (United States)

    Balaton, Bradley P; Brown, Carolyn J

    2016-06-01

    Inactivation of one X chromosome in mammalian females achieves dosage compensation between XX females and XY males; however, over 15% of human X-linked genes continue to be expressed from the inactive X chromosome. New genomic methodologies have improved our identification and characterization of these escape genes, revealing the importance of DNA sequence, chromatin structure, and chromosome ultrastructure in regulating expression from an otherwise inactive chromosome. Study of these exceptions to the rule of silencing highlights the interconnectedness of chromatin and chromosome structure in X-chromosome inactivation (XCI). Recent advances also demonstrate the importance of these genes in sexually dimorphic disease risk, particularly cancer. PMID:27103486

  18. Adults with Chromosome 18 Abnormalities.

    Science.gov (United States)

    Soileau, Bridgette; Hasi, Minire; Sebold, Courtney; Hill, Annice; O'Donnell, Louise; Hale, Daniel E; Cody, Jannine D

    2015-08-01

    The identification of an underlying chromosome abnormality frequently marks the endpoint of a diagnostic odyssey. However, families are frequently left with more questions than answers as they consider their child's future. In the case of rare chromosome conditions, a lack of longitudinal data often makes it difficult to provide anticipatory guidance to these families. The objective of this study is to describe the lifespan, educational attainment, living situation, and behavioral phenotype of adults with chromosome 18 abnormalities. The Chromosome 18 Clinical Research Center has enrolled 483 individuals with one of the following conditions: 18q-, 18p-, Tetrasomy 18p, and Ring 18. As a part of the ongoing longitudinal study, we collect data on living arrangements, educational level attained, and employment status as well as data on executive functioning and behavioral skills on an annual basis. Within our cohort, 28 of the 483 participants have died, the majority of whom have deletions encompassing the TCF4 gene or who have unbalanced rearrangement involving other chromosomes. Data regarding the cause of and age at death are presented. We also report on the living situation, educational attainment, and behavioral phenotype of the 151 participants over the age of 18. In general, educational level is higher for people with all these conditions than implied by the early literature, including some that received post-high school education. In addition, some individuals are able to live independently, though at this point they represent a minority of patients. Data on executive function and behavioral phenotype are also presented. Taken together, these data provide insight into the long-term outcome for individuals with a chromosome 18 condition. This information is critical in counseling families on the range of potential outcomes for their child. PMID:25403900

  19. Phosphorylation of HPV-16 E2 at serine 243 enables binding to Brd4 and mitotic chromosomes.

    Directory of Open Access Journals (Sweden)

    Szu-Wei Chang

    Full Text Available The papillomavirus E2 protein is involved in the maintenance of persistent infection and known to bind either to cellular factors or directly to mitotic chromosomes in order to partition the viral genome into the daughter cells. However, how the HPV-16 E2 protein acts to facilitate partitioning of the viral genome remains unclear. In this study, we found that serine 243 of HPV-16 E2, located in the hinge region, is crucial for chromosome binding during mitosis. Bromodomain protein 4 (Brd4 has been identified as a cellular binding target through which the E2 protein of bovine papillomavirus type 1 (BPV-1 tethers the viral genome to mitotic chromosomes. Mutation analysis showed that, when the residue serine 243 was substituted by glutamic acid or aspartic acid, whose negative charges mimic the effect of constitutive phosphorylation, the protein still can interact with Brd4 and colocalize with Brd4 in condensed metaphase and anaphase chromosomes. However, substitution by the polar uncharged residues asparagine or glutamine abrogated Brd4 and mitotic chromosome binding. Moreover, following treatment with the inhibitor JQ1 to release Brd4 from the chromosomes, Brd4 and E2 formed punctate foci separate from the chromosomes, further supporting the hypothesis that the association of the HPV-16 E2 protein with the chromosomes is Brd4-dependent. In addition, the S243A E2 protein has a shorter half-life than the wild type, indicating that phosphorylation of the HPV-16 E2 protein at serine 243 also increases its half-life. Thus, phosphorylation of serine 243 in the hinge region of HPV-16 E2 is essential for interaction with Brd4 and required for host chromosome binding.

  20. Making chromosome abnormalities treatable conditions.

    Science.gov (United States)

    Cody, Jannine DeMars; Hale, Daniel Esten

    2015-09-01

    Individuals affected by the classic chromosome deletion syndromes which were first identified at the beginning of the genetic age, are now positioned to benefit from genomic advances. This issue highlights five of these conditions (4p-, 5p-, 11q-, 18p-, and 18q-). It focuses on the increased in understanding of the molecular underpinnings and envisions how these can be transformed into effective treatments. While it is scientifically exciting to see the phenotypic manifestations of hemizygosity being increasingly understood at the molecular and cellular level, it is even more amazing to consider that we are now on the road to making chromosome abnormalities treatable conditions. PMID:26351122

  1. Normal psychomotor development in a child with mosaic trisomy and pericentric inversion of chromosome 9.

    OpenAIRE

    Frydman, M; Shabtal, F; Halbrecht, I; Elian, E

    1981-01-01

    A female infant with trisomy 9 in 58% of her cells is reported. Multiple congenital malformations were present, but she had normal psychomotor development. A pericentric inversion involving a portion of the centromeric heterochromatin of chromosome 9 was identified in the patient and her mother. This variant chromosome 9 was present in duplicate in the trisomic line. Since similar variants of 9qh have been found repeatedly in this syndrome, we feel that this association may be a non-random one.

  2. Two complementary recombinant chromosomes 5 in a healthy woman.

    Science.gov (United States)

    Bartsch, O; Ergun, M A; Balci, S; Kan, D; Eggermann, T; Kotzot, D

    2006-01-01

    We report a healthy woman with two abortions who is a carrier for a rare heterozygous double recombinant of an inv(5) chromosome, karyotype 46,XX,rec(5)dup(5p) inv(5)(p13q22),rec(5)dup(5q)inv(5)(p13q22). Her father had a 46,XY,inv(5)(p13q22) karyotype; his consanguineous wife had died. Molecular investigation of 11 highly polymorphic markers spanning chromosome 5 revealed biparental inheritance for two markers (D5S406, D5S681) on 5p15.3 and 5q13.1, and an allele constellation not compatible with paternal heterodisomy for marker D5S623 on 5q11.2. Eight markers were not informative. Three mechanisms of formation are proposed: First, fertilization of a normal oocyte by a sperm carrying the two recombinant chromosomes 5, followed by postzygotic recombination between the normal maternal homologue and the rec(5)dup(5p), and by loss of the mitotically recombined maternal homologue, leading to segmental paternal heterodisomy 5q13-->qter (trisomic rescue). Second, postzygotic recombination in a 46,XX,inv(5)(p13q22) zygote resulting in the 46,XX,rec(5)dup(5p)inv(5)(p13q22),rec(5) dup(5q)inv(5)(p13q22) karyotype, followed by absence of the original cell line in lymphocytes. Third and most likely, both parents were inv(5) carriers and complementary recombinations in maternal and paternal meiosis resulted in a zygote with two recombinant chromosomes 5. Our patient refused any further studies but later reported the birth of a phenotypically normal child. This is the first report known to us of complementation by two non-homologous recombinant chromosomes in a phenotypically normal woman, and the first example of a child born to a carrier of complementary recombinant chromosomes. PMID:16825772

  3. Using Chromosomes to Teach Evolution: Chromosomal Rearrangements in Speciation Events.

    Science.gov (United States)

    Offner, Susan

    1994-01-01

    Uses diagrams to aid in discussing how the English map of the human chromosomes, published by Offner in 1993, can be used to illustrate some important questions in evolution, as well as give students a glimpse into some of the mechanisms underlying evolutionary change. (ZWH)

  4. Chromothripsis-like chromosomal rearrangements induced by ionizing radiation using proton microbeam irradiation system.

    Science.gov (United States)

    Morishita, Maki; Muramatsu, Tomoki; Suto, Yumiko; Hirai, Momoki; Konishi, Teruaki; Hayashi, Shin; Shigemizu, Daichi; Tsunoda, Tatsuhiko; Moriyama, Keiji; Inazawa, Johji

    2016-03-01

    Chromothripsis is the massive but highly localized chromosomal rearrangement in response to a one-step catastrophic event, rather than an accumulation of a series of subsequent and random alterations. Chromothripsis occurs commonly in various human cancers and is thought to be associated with increased malignancy and carcinogenesis. However, the causes and consequences of chromothripsis remain unclear. Therefore, to identify the mechanism underlying the generation of chromothripsis, we investigated whether chromothripsis could be artificially induced by ionizing radiation. We first elicited DNA double-strand breaks in an oral squamous cell carcinoma cell line HOC313-P and its highly metastatic subline HOC313-LM, using Single Particle Irradiation system to Cell (SPICE), a focused vertical microbeam system designed to irradiate a spot within the nuclei of adhesive cells, and then established irradiated monoclonal sublines from them, respectively. SNP array analysis detected a number of chromosomal copy number alterations (CNAs) in these sublines, and one HOC313-LM-derived monoclonal subline irradiated with 200 protons by the microbeam displayed multiple CNAs involved locally in chromosome 7. Multi-color FISH showed a complex translocation of chromosome 7 involving chromosomes 11 and 12. Furthermore, whole genome sequencing analysis revealed multiple de novo complex chromosomal rearrangements localized in chromosomes 2, 5, 7, and 20, resembling chromothripsis. These findings suggested that localized ionizing irradiation within the nucleus may induce chromothripsis-like complex chromosomal alterations via local DNA damage in the nucleus. PMID:26862731

  5. Alternative Lengthening of Telomeres: Recurrent Cytogenetic Aberrations and Chromosome Stability under Extreme Telomere Dysfunction

    Directory of Open Access Journals (Sweden)

    Despoina Sakellariou

    2013-11-01

    Full Text Available Human tumors using the alternative lengthening of telomeres (ALT exert high rates of telomere dysfunction. Numerical chromosomal aberrations are very frequent, and structural rearrangements are widely scattered among the genome. This challenging context allows the study of telomere dysfunction-driven chromosomal instability in neoplasia (CIN in a massive scale. We used molecular cytogenetics to achieve detailed karyotyping in 10 human ALT neoplastic cell lines.We identified 518 clonal recombinant chromosomes affected by 649 structural rearrangements. While all human chromosomes were involved in random or clonal, terminal, or pericentromeric rearrangements and were capable to undergo telomere healing at broken ends, a differential recombinatorial propensity of specific genomic regions was noted.We show that ALT cells undergo epigenetic modifications rendering polycentric chromosomes functionally monocentric, and because of increased terminal recombinogenicity, they generate clonal recombinant chromosomes with interstitial telomeric repeats. Losses of chromosomes 13, X, and 22, gains of 2, 3, 5, and 20, and translocation/deletion events involving several common chromosomal fragile sites (CFSs were recurrent. Long-term reconstitution of telomerase activity in ALT cells reduced significantly the rates of random ongoing telomeric and pericentromeric CIN. However, the contribution of CFS in overall CIN remained unaffected, suggesting that in ALT cells whole-genome replication stress is not suppressed by telomerase activation. Our results provide novel insights into ALT-driven CIN, unveiling in parallel specific genomic sites that may harbor genes critical for ALT cancerous cell growth.

  6. Alternative lengthening of telomeres: recurrent cytogenetic aberrations and chromosome stability under extreme telomere dysfunction.

    Science.gov (United States)

    Sakellariou, Despoina; Chiourea, Maria; Raftopoulou, Christina; Gagos, Sarantis

    2013-11-01

    Human tumors using the alternative lengthening of telomeres (ALT) exert high rates of telomere dysfunction. Numerical chromosomal aberrations are very frequent, and structural rearrangements are widely scattered among the genome. This challenging context allows the study of telomere dysfunction-driven chromosomal instability in neoplasia (CIN) in a massive scale. We used molecular cytogenetics to achieve detailed karyotyping in 10 human ALT neoplastic cell lines. We identified 518 clonal recombinant chromosomes affected by 649 structural rearrangements. While all human chromosomes were involved in random or clonal, terminal, or pericentromeric rearrangements and were capable to undergo telomere healing at broken ends, a differential recombinatorial propensity of specific genomic regions was noted. We show that ALT cells undergo epigenetic modifications rendering polycentric chromosomes functionally monocentric, and because of increased terminal recombinogenicity, they generate clonal recombinant chromosomes with interstitial telomeric repeats. Losses of chromosomes 13, X, and 22, gains of 2, 3, 5, and 20, and translocation/deletion events involving several common chromosomal fragile sites (CFSs) were recurrent. Long-term reconstitution of telomerase activity in ALT cells reduced significantly the rates of random ongoing telomeric and pericentromeric CIN. However, the contribution of CFS in overall CIN remained unaffected, suggesting that in ALT cells whole-genome replication stress is not suppressed by telomerase activation. Our results provide novel insights into ALT-driven CIN, unveiling in parallel specific genomic sites that may harbor genes critical for ALT cancerous cell growth. PMID:24339742

  7. Characterization of chromosome structures of Falconinae (Falconidae, Falconiformes, Aves) by chromosome painting and delineation of chromosome rearrangements during their differentiation

    OpenAIRE

    Nishida, Chizuko; Ishijima, Junko; KOSAKA, Ayumi; Tanabe, Hideyuki; Habermann, Felix A.; Griffin, Darren K.; MATSHUDA, Yoichi; 秀之, 田辺

    2008-01-01

    Karyotypes of most bird species are characterized by around 2n = 80 chromosomes, comprising 7–10 pairs of large- and medium-sized macrochromosomes including sex chromosomes and numerous morphologically indistinguishable microchromosomes. The Falconinae of the Falconiformes has a different karyotype from the typical avian karyotype in low chromosome numbers, little size difference between macrochromosomes and a smaller number of microchromosomes. To characterize chromosome structures of Falcon...

  8. Characterization of chromosome structures of Falconinae (Falconidae, Falconiformes, Aves) by chromosome painting and delineation of chromosome rearrangements during their differentiation

    OpenAIRE

    Nishida, Chizuko; Ishijima, Junko; KOSAKA, Ayumi; Tanabe, Hideyuki; Habermann, Felix A.; Griffin, Darren K.; Matsuda, Yoichi

    2008-01-01

    Karyotypes of most bird species are characterized by around 2n = 80 chromosomes, comprising 7Y10 pairs of large- and medium-sized macrochromosomes including sex chromosomes and numerous morphologically indistinguishable microchromosomes. The Falconinae of the Falconiformes has a different karyotype from the typical avian karyotype in low chromosome numbers, little size difference between macrochromosomes and a smaller number of microchromosomes. To characterize chromosome structures of Falcon...

  9. Triplex targeted genomic crosslinks enter separable deletion and base substitution pathways

    OpenAIRE

    Richards, Sally; Liu, Su-ting; Majumdar, Alokes; Liu, Ji-Lan; Nairn, Rodney S.; Bernier, Michel; Maher, Veronica; Seidman, Michael M.

    2005-01-01

    We have synthesized triple helix forming oligonucleotides (TFOs) that target a psoralen (pso) interstrand crosslink to a specific chromosomal site in mammalian cells. Mutagenesis of the targeted crosslinks results in base substitutions and deletions. Identification of the gene products involved in mutation formation is important for developing practical applications of pso-TFOs, and may be informative about the metabolism of other interstrand crosslinks. We have studied mutagenesis of a pso-T...

  10. Cladistic association analysis of Y chromosome effects on alcohol dependence and related personality traits

    OpenAIRE

    Kittles, Rick A.; Long, Jeffrey C.; Bergen, Andrew W; Eggert, Monica; Virkkunen, Matti; Linnoila, Markku; Goldman, David

    1999-01-01

    Association between Y chromosome haplotype variation and alcohol dependence and related personality traits was investigated in a large sample of psychiatrically diagnosed Finnish males. Haplotypes were constructed for 359 individuals using alleles at eight loci (seven microsatellite loci and a nucleotide substitution in the DYZ3 alphoid satellite locus). A cladogram linking the 102 observed haplotype configurations was constructed by using parsimony with a single-step mutation model. Then, a ...

  11. Study on the cytotoxicity and chromosome aberration following implantation of sea coral in rabbits

    OpenAIRE

    Kannan TP; Freeda Woon Faiza Woon Tai Keat; Widowati Witjaksono; Abdul Rani Samsudin

    2006-01-01

    Coral has been used as a bone substitute in many experimental studies. It has been proven to be biocompatible, biodegradable and easy to handle: and it has not been found to cause any inflammatory responses. The present study was undertaken to determine the cytotoxicity in terms of mitotic index as well as the clastogenic effect (chromosome aberration) of sea coral implantation in rabbits. The animals comprised of five male adult healthy New Zealand White (Oryctolagus cuniculus) rabbits. The ...

  12. Hazardous solvent substitution

    International Nuclear Information System (INIS)

    Eliminating hazardous solvents is good for the environment, worker safety, and the bottom line. However, even though we are motivated to find replacements, the big question is 'What can we use as replacements for hazardous solvents?'You, too, can find replacements for your hazardous solvents. All you have to do is search for them. Search through the vendor literature of hundreds of companies with thousands of products. Ponder the associated material safety data sheets, assuming of course that you can obtain them and, having obtained them, that you can read them. You will want to search the trade magazines and other sources for product reviews. You will want to talk to users about how well the product actually works. You may also want to check US Environmental Protection Agency (EPA) and other government reports for toxicity and other safety information. And, of course, you will want to compare the product's constituent chemicals with the many hazardous constituency lists to ensure the safe and legal use of the product in your workplace

  13. Mathematical glimpse on the Y chromosome degeneration

    Science.gov (United States)

    Lobo, M. P.

    2006-04-01

    The Y chromosomes are genetically degenerate and do not recombine with their matching partners X. Non-recombination of XY pairs has been pointed out as the key factor for the degeneration of the Y chromosome. The aim here is to show that there is a mathematical asymmetry in sex chromosomes which leads to the degeneration of Y chromosomes even in the absence of XX and XY recombination. A model for sex-chromosome evolution in a stationary regime is proposed. The consequences of their asymmetry are analyzed and lead us to a couple of conclusions. First, Y chromosome degeneration shows up sqrt{2} more often than X chromosome degeneration. Second, if nature prohibits female mortalities from beeing exactly 50%, then Y chromosome degeneration is inevitable.

  14. 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 ...

  15. 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...

  16. 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. PMID:27505434

  17. Chromosome Territory Modeller and Viewer

    Science.gov (United States)

    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. PMID:27505434

  18. 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.

  19. Multicolor spectral karyotyping of human chromosomes.

    Science.gov (United States)

    Schröck, E; du Manoir, S; Veldman, T; Schoell, B; Wienberg, J; Ferguson-Smith, M A; Ning, Y; Ledbetter, D H; Bar-Am, I; Soenksen, D; Garini, Y; Ried, T

    1996-07-26

    The simultaneous and unequivocal discernment of all human chromosomes in different colors would be of significant clinical and biologic importance. Whole-genome scanning by spectral karyotyping allowed instantaneous visualization of defined emission spectra for each human chromosome after fluorescence in situ hybridization. By means of computer separation (classification) of spectra, spectrally overlapping chromosome-specific DNA probes could be resolved, and all human chromosomes were simultaneously identified. PMID:8662537

  20. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH SPERM DISORDERS

    OpenAIRE

    L. Y. Pylyp; L. A. Spinenko; V. D. Zukin; N. M. Bilko

    2013-01-01

    Chromosomal abnormalities are among the most common genetic causes of spermatogenic disruptions. Carriers of chromosomal abnormalities are at increased risk of infertility, miscarriage or birth of a child with unbalanced karyotype due to the production of unbalanced gametes. The natural selection against chromosomally abnormal sperm usually prevents fertilization with sperm barring in cases of serious chromosomal abnormalities. However, assisted reproductive technologies in general and intrac...

  1. Evolution of sex chromosomes ZW of Schistosoma mansoni inferred from chromosome paint and BAC mapping analyses.

    Science.gov (United States)

    Hirai, Hirohisa; Hirai, Yuriko; LoVerde, Philip T

    2012-12-01

    Chromosomes of schistosome parasites among digenetic flukes have a unique evolution because they exhibit the sex chromosomes ZW, which are not found in the other groups of flukes that are hermaphrodites. We conducted molecular cytogenetic analyses for investigating the sex chromosome evolution using chromosome paint analysis and BAC clones mapping. To carry this out, we developed a technique for making paint probes of genomic DNA from a single scraped chromosome segment using a chromosome microdissection system, and a FISH mapping technique for BAC clones. Paint probes clearly identified each of the 8 pairs of chromosomes by a different fluorochrome color. Combination analysis of chromosome paint analysis with Z/W probes and chromosome mapping with 93 BAC clones revealed that the W chromosome of Schistosoma mansoni has evolved by at least four inversion events and heterochromatinization. Nine of 93 BAC clones hybridized with both the Z and W chromosomes, but the locations were different between Z and W chromosomes. The homologous regions were estimated to have moved from the original Z chromosome to the differentiated W chromosome by three inversions events that occurred before W heterohcromatinization. An inversion that was observed in the heterochromatic region of the W chromosome likely occurred after W heterochromatinization. These inversions and heterochromatinization are hypothesized to be the key factors that promoted the evolution of the W chromosome of S. mansoni. PMID:22831897

  2. Chromosome Aberrations by Heavy Ions

    Science.gov (United States)

    Ballarini, Francesca; Ottolenghi, Andrea

    It is well known that mammalian cells exposed to ionizing radiation can show different types of chromosome aberrations (CAs) including dicentrics, translocations, rings, deletions and complex exchanges. Chromosome aberrations are a particularly relevant endpoint in radiobiology, because they play a fundamental role in the pathways leading either to cell death, or to cell conversion to malignancy. In particular, reciprocal translocations involving pairs of specific genes are strongly correlated (and probably also causally-related) with specific tumour types; a typical example is the BCR-ABL translocation for Chronic Myeloid Leukaemia. Furthermore, aberrations can be used for applications in biodosimetry and more generally as biomarkers of exposure and risk, that is the case for cancer patients monitored during Carbon-ion therapy and astronauts exposed to space radiation. Indeed hadron therapy and astronauts' exposure to space radiation represent two of the few scenarios where human beings can be exposed to heavy ions. After a brief introduction on the main general features of chromosome aberrations, in this work we will address key aspects of the current knowledge on chromosome aberration induction, both from an experimental and from a theoretical point of view. More specifically, in vitro data will be summarized and discussed, outlining important issues such as the role of interphase death/mitotic delay and that of complex-exchange scoring. Some available in vivo data on cancer patients and astronauts will be also reported, together with possible interpretation problems. Finally, two of the few available models of chromosome aberration induction by ionizing radiation (including heavy ions) will be described and compared, focusing on the different assumptions adopted by the authors and on how these models can deal with heavy ions.

  3. Detecting deletions, insertions, and single nucleotide substitutions in cloned β-globin genes and new polymorphic nucleotide substitutions in β-globin genes in a Japanese population using ribonuclease cleavage at mismatches in RNA: DNA duplexes

    International Nuclear Information System (INIS)

    The applicability of ribonuclease (RNase) cleavage at mismatches in RNA:DNA duplexes (the RNase cleavage method) for determining nucleotide variant rates was examined in a Japanese population. DNA segments of various lengths obtained from four different regions of one normal and three thalassemic cloned human β-globin genes were inserted into transcription vectors. Sense and antisense RNA probes uniformly labeled with 32P were prepared. When RNA probes of 771 nucleotides (nt) or less were hybridized with cloned DNAs and the resulting duplexes were treated with a mixture of RNases A and T1, the length of products agreed with theoretical values. Twelve possible mismatches were examined. Since both sense and antisense probes were used, uncleavable mismatches such as G:T and G:G which were made from one combination of RNA and DNA strands could be converted to the cleavable C:A and C:C mismatches, respectively, by using the opposite combination. Deletions and insertions of one (G), four(TTCT), five (ATTTT), and 10 (ATTTTATTTT) nt were easily detected. A polymorphic substitution of T to C at position 666 of the second intervening sequence (IVS2-666) of the β-globin gene was detected using genomic DNAs from cell lines established from the peripheral B lymphocytes of 59 unrelated Japanese from Hiroshima or those amplified by polymerase chain reaction (PCR). The frequency of the gene with C at the IVS2-666 (allele C) was 0.48 and that of the gene with T (allene T) was 0.52. Two new polymorphic substitutions of C to A and A to T were detected at nucleotide positions 1789 and 1945 from the capping site, respectively, using genomic DNAs amplified by PCR. We conclude that it would be feasible to use the RNase cleavage method combined with PCR for large-scale screening of variation in chromosomal DNA. (J.P.N.)

  4. A case of trisomy of chromosome 15

    OpenAIRE

    Coldwell, S; Fitzgerald, B.; Semmens, J.M.; Ede, R; Bateman, C

    1981-01-01

    We describe a case of trisomy of chromosome 15 in an infant who presented at birth with numerous abnormalities. As far as we are aware this chromosomal abnormality has not been described before. On the basis of this one case there appear to be no features which are specific to this chromosomal abnormality.

  5. Commercial formalin substitutes for histopathology

    DEFF Research Database (Denmark)

    Prentø, P; Lyon, H

    1997-01-01

    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 of...... 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...... was obtained by combining formalin fixation with antigen retrieval. We conclude that none of the proposed commercial substitutes for buffered formalin are adequate for critical histology or histopathology....

  6. Substitution systems and nonextensive statistics

    Science.gov (United States)

    García-Morales, V.

    2015-12-01

    Substitution systems evolve in time by generating sequences of symbols from a finite alphabet: At a certain iteration step, the existing symbols are systematically replaced by blocks of Nk symbols also within the alphabet (with Nk, a natural number, being the length of the kth block of the substitution). The dynamics of these systems leads naturally to fractals and self-similarity. By using B-calculus (García-Morales, 2012) universal maps for deterministic substitution systems both of constant and non-constant length, are formulated in 1D. It is then shown how these systems can be put in direct correspondence with Tsallis entropy. A 'Second Law of Thermodynamics' is also proved for these systems in the asymptotic limit of large words.

  7. THE PROBLEM OF SENSES SUBSTITUTION

    Directory of Open Access Journals (Sweden)

    Oreshkina M. A.

    2015-10-01

    Full Text Available The author deals with problems of substitution of senses and notions in the science and in the social life. Such processes result not only in distortion of the scientific worldview but also in absolutely undesirable social cataclysms. However, this scientific problem has not been yet worked out to sufficient extent, which hampers preventing the mentioned distortions of the real worldview and brings to unwanted consequences requiring correlation and corrections. The question of senses and notions substitution is not new in the science but it has not been yet sufficiently studied. We know that strictness of thinking must be dearly paid for in loss of flexibility in revaluation of senses, which makes you easily slip into dogmatism. It should be noted that this keeps taking place both in the science itself and in the life of society any science is called to serve. So the science can be hardly imagined without schools of thought. They ensure preservation of certain knowledge, vision, approach and, finally, of a certain school – they are traditions and authority of the science. However, having passed their golden age, when the founder used to be followed after several generations by dogmatists whose genius and talent were far from being so great, a school begins to degrade producing scholasticism by substitution and emasculation of senses and notions and finally destructs itself. The collectivization in the USSR in the 30ies of the 20th century and so-called “extremes” associated with it being that very substitution of sense platforms in its pure form constitutes a rather illustrative example of social manipulation based on the substitution of sense platforms. These activities relating to detection of senses and notions substitution will also be developed in the future. The truth will be approached as before through cleaning the knowledge of the myth, through searching for the original sense or the archetype separated from lie and fabrication

  8. 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.

  9. 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. PMID:27280692

  10. 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

  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. Holoprosencephaly due to numeric chromosome abnormalities.

    Science.gov (United States)

    Solomon, Benjamin D; Rosenbaum, Kenneth N; Meck, Jeanne M; Muenke, Maximilian

    2010-02-15

    Holoprosencephaly (HPE) is the most common malformation of the human forebrain. When a clinician identifies a patient with HPE, a routine chromosome analysis is often the first genetic test sent for laboratory analysis in order to assess for a structural or numerical chromosome anomaly. An abnormality of chromosome number is overall the most frequently identified etiology in a patient with HPE. These abnormalities include trisomy 13, trisomy 18, and triploidy, though several others have been reported. Such chromosome number abnormalities are almost universally fatal early in gestation or in infancy. Clinical features of specific chromosome number abnormalities may be recognized by phenotypic manifestations in addition to the HPE. PMID:20104610

  13. Novel insights into mitotic chromosome condensation

    Science.gov (United States)

    Piskadlo, Ewa; Oliveira, Raquel A.

    2016-01-01

    The fidelity of mitosis is essential for life, and successful completion of this process relies on drastic changes in chromosome organization at the onset of nuclear division. The mechanisms that govern chromosome compaction at every cell division cycle are still far from full comprehension, yet recent studies provide novel insights into this problem, challenging classical views on mitotic chromosome assembly. Here, we briefly introduce various models for chromosome assembly and known factors involved in the condensation process (e.g. condensin complexes and topoisomerase II). We will then focus on a few selected studies that have recently brought novel insights into the mysterious way chromosomes are condensed during nuclear division.

  14. Somatic Chromosomes of the Bornean Sambar Deer and Rusa Deer Interspecific Hybrids

    Directory of Open Access Journals (Sweden)

    Ismail Idris

    2009-01-01

    Full Text Available Problem statement: Hybridization has potential benefits to the Malaysian farmed deer industries in terms of increased growth rate and increased proportion of muscle and an improved alignment of feed supply and annual energy requirement. Species or subspecies of different chromosome constitution could mate to produce healthy hybrid offspring in a normal ratio of males and females. If any of the hybrid offspring were sterile, the sterile offspring would be the heterogametic offspring. The study investigated the use of chromosome banding method to detect chromosomal variation and to define the chromosome homology and the possibility of the Bornean Sambar deer (Cervus unicolor brookei and Rusa deer (Cervus timorensis hybrids to reproduce. Approach: Samples were collected from the Livestock Breeding Station, Sabrang, Keningau, Sabah, East Malaysia. The animals studied consisted of two deer subspecies namely the Bornean Sambar deer, Rusa deer and their hybrids. The karyotypes of the Bornean Sambar deer, Rusa deer and their F1 hybrids have been investigated by solid giemsa staining, G-banding and Ag-NOR banding techniques. Results: Rusa and Bornean Sambar have different chromosome number; 60 and 62 respectively, but share the same fundamental number of chromosome arm, 70. The hybrids have 2n = 61, consisting of 9 metacentric to submetacentric autosomes and 24 pairs of acrocentric autosomes with two acrocentrics and one submetacentric chromosome being unpaired. The morphology of the sex chromosomes in the F1 hybrids was similar to that of the parental species. The Ag-NOR pattern and the conventional Giemsa staining of chromosomes were effective as markers in the characterization of the karyotypes of the parental lines and hybrids because of the presence of active NORs on different chromosomes of different species. G-band, in contrast, showed complete homology in the presence of euchromatic bands and heterochromatin blocks respectively on each chromosome

  15. Combinatorial substitutions and sofic tilings

    CERN Document Server

    Fernique, Thomas

    2010-01-01

    A combinatorial substitution is a map over tilings which allows to define sets of tilings with a strong hierarchical structure. In this paper, we show that such sets of tilings are sofic, that is, can be enforced by finitely many local constraints. This extends some similar previous results (Mozes'90, Goodmann-Strauss'98) in a much shorter presentation.

  16. 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

  17. Transient Microgeographic Clines during B Chromosome Invasion.

    Science.gov (United States)

    Camacho, Juan Pedro M; Shaw, Michael W; Cabrero, Josefa; Bakkali, Mohammed; Ruíz-Estévez, Mercedes; Ruíz-Ruano, Francisco J; Martín-Blázquez, Rubén; López-León, María Dolores

    2015-11-01

    The near-neutral model of B chromosome evolution predicts that the invasion of a new population should last some tens of generations, but the details on how it proceeds in real populations are mostly unknown. Trying to fill this gap, we analyze here a natural population of the grasshopper Eyprepocnemis plorans at three time points during the last 35 years. Our results show that B chromosome frequency increased significantly during this period and that a cline observed in 1992 had disappeared in 2012 once B chromosome frequency reached an upper limit at all sites sampled. This indicates that, during B chromosome invasion, transient clines for B chromosome frequency are formed at the invasion front on a microgeographic scale. Computer simulation experiments showed that the pattern of change observed for genotypic frequencies is consistent with the existence of B chromosome drive through females and selection against individuals with a high number of B chromosomes. PMID:26655780

  18. Mitosis. Microtubule detyrosination guides chromosomes during mitosis.

    Science.gov (United States)

    Barisic, Marin; Silva e Sousa, Ricardo; Tripathy, Suvranta K; Magiera, Maria M; Zaytsev, Anatoly V; Pereira, Ana L; Janke, Carsten; Grishchuk, Ekaterina L; Maiato, Helder

    2015-05-15

    Before chromosomes segregate into daughter cells, they align at the mitotic spindle equator, a process known as chromosome congression. Centromere-associated protein E (CENP-E)/Kinesin-7 is a microtubule plus-end-directed kinetochore motor required for congression of pole-proximal chromosomes. Because the plus-ends of many astral microtubules in the spindle point to the cell cortex, it remains unknown how CENP-E guides pole-proximal chromosomes specifically toward the equator. We found that congression of pole-proximal chromosomes depended on specific posttranslational detyrosination of spindle microtubules that point to the equator. In vitro reconstitution experiments demonstrated that CENP-E-dependent transport was strongly enhanced on detyrosinated microtubules. Blocking tubulin tyrosination in cells caused ubiquitous detyrosination of spindle microtubules, and CENP-E transported chromosomes away from spindle poles in random directions. Thus, CENP-E-driven chromosome congression is guided by microtubule detyrosination. PMID:25908662

  19. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH RECURRENT MISCARRIAGE

    Directory of Open Access Journals (Sweden)

    Daniela Mierla

    2012-06-01

    Full Text Available Chromosomal abnormalities are involved in the etiology of recurrent spontaneous pregnancy loss and sub-fertility. The purpose of this study was to determine the frequency and contribution of chromosomal abnormalities in recurrent miscarriages. The results obtained and literature review are helpful in understanding the importance of cytogenetics analysis of female infertility. To investigate the distribution of chromosomal abnormalities in the Romanian population with recurrent miscarriage, karyotype analysis by G-banding was performed from peripheral blood in 967 women infertility. Results: Chromosomal abnormalities were found to 79 women (8,17%. The percentage of chromosomal abnormalities in the studied population correlates with the data in the literature. Chromosomal abnormalities could play the important role in etiology of infertility and are more frequently detected in this group of patients compared to general population. In the infertile couples balanced chromosomal abnormalities are the main cause of spontaneous abortions.

  20. [The evolution of human Y chromosome].

    Science.gov (United States)

    Yang, Xianrong; Wang, Meiqin; Li, Shaohua

    2014-09-01

    The human Y chromosome is always intriguing for researchers, because of its role in gender determination and its unusual evolutionary history. The Y chromosome evolves from an autosome, and its evolution has been characterized by massive gene decay. The lack of recombination and protein-coding genes and high content of repetitive sequences have hindered the progress in our understanding of the Y chromosome biology. Recently, with the advances in comparative genomics and sequencing technology, the research on Y chromosome has become a hotspot, with an intensified debate about Y-chromosome final destination resulting from degeneration. This review focuses on the structure, inheritance characteristics, gene content, and the origin and evolution of Y chromosome. We also discuss the long-term destiny of Y chromosome. PMID:25252301

  1. 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 this...... and reliable method enabled us to start the analysis on the distribution of various chromosomal loci inside slowly growing cells. With the actual counting and measuring no longer being any problem we could easily analyze 14 loci distributed on the E.coli chromosome. More than 15.000 cells were...... on the P1 par system. Using the new system, which is based on the pMT1 par system from Yersenia pestis, we labeled loci on opposite sides of the E.coli chromosome simultaneously and were able to show that the E.coli chromosome is organized with one chromosomal arm in each cell half. This astounding...

  2. International workshop of chromosome 19

    Energy Technology Data Exchange (ETDEWEB)

    Pericak-Vance, M.A. (Duke Univ. Medical Center, Durham, NC (United States). Div. of Neurology); Carrano, A.J. (Lawrence Livermore National Lab., CA (United States))

    1991-09-16

    This document summarizes the workshop on physical and genetic mapping of chromosome 19. The first session discussed the major disease loci found on the chromosome. The second session concentrated on reference families, markers and linkage maps. The third session concentrated on radiation hybrid mapping, somatic cell hybrid panels, macro restriction maps and YACs, followed by cDNA and long range physical maps. The fourth session concentrated on compiling consensus genetic and physical maps as well as discussing regions of conflict. The final session dealt with the LLNL cosmid contig database and comparative mapping of homologous regions of the human and mouse genomes, and ended with a discussion of resource sharing. 18 refs., 2 figs. (MHB)

  3. Baseline chromosome aberrations in children

    Czech Academy of Sciences Publication Activity Database

    Merlo, D.F.; Ceppi, M.; Stagi, E.; Bocchini, V.; Šrám, Radim; Rössner st., Pavel

    2007-01-01

    Roč. 172, - (2007), s. 60-67. ISSN 0378-4274 Grant ostatní: EU(EU) 2002-02198; EU(EU) 2005-016320 Institutional research plan: CEZ:AV0Z50390512 Source of funding: R - rámcový projekt EK ; R - rámcový projekt EK Keywords : chromosome aberrations * children * molecular epidemiology Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.826, year: 2007

  4. Clonality - X Chromosome Inactivation Assay

    OpenAIRE

    sprotocols

    2014-01-01

    Author: Molecular Profiling Initiative, NCI This method was successful in our lab using prostate tissue and for our specific objectives. Investigators must be aware that they will need to tailor the following protocol for their own research objectives and tissue under study. Investigators can utilize X chromosome inactivation (methylation) to determine the clonality status of a tumor or premalignant lesion in females. The technique is based on a methylation-sensitive restriction enzym...

  5. 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.

  6. Assignment of the human pancreatic regenerating (REG) gene to chromosome 2p12

    Energy Technology Data Exchange (ETDEWEB)

    Perfetti, R.; Egan, J.M.; Zenilman, M.E.; Shuldiner, A.R.; Hawkins, A.L.; Griffin, C.A. (Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States))

    1994-03-15

    A cDNA termed reg (for regenerating gene) has been isolated and characterized from a rat pancreatic library. Expression of reg is markedly increased in regenerating islets and decreased when insulin gene expression is inhibited. These findings have led to the hypothesis that reg may be involved in the expansion [beta]-cell function. The human reg gene has a high degree of similarity to the rat reg gene. To determine the chromosomal location of the human reg gene, the authors analyzed two panels of mouse- or hamster-human hybrid cell lines containing a single human chromosome or several different human chromosomes. DNA extracts from these cell lines were analyzed for the presence of the human reg gene by polymerase chain reaction. In addition, human metaphase chromosomes were used for fluorescence in situ hybridization to further confirm the chromosomal assignment and to determine the subchromosomal localization. With these approaches, they show that the human reg gene is located on the short arm of chromosome 2 near the centromere at band 2p12. 17 refs., 2 figs.

  7. Substitution patterns are GC-biased in divergent sequences across the metazoans.

    Science.gov (United States)

    Capra, John A; Pollard, Katherine S

    2011-01-01

    The fastest-evolving regions in the human and chimpanzee genomes show a remarkable excess of weak (A,T) to strong (G,C) nucleotide substitutions since divergence from their common ancestor. We investigated the phylogenetic extent and possible causes of this weak to strong (W → S) bias in divergent sequences (BDS) using recently sequenced genomes and recombination maps from eight trios of eukaryotic species. To quantify evidence for BDS, we inferred substitution histories using an efficient maximum likelihood approach with a context-dependent evolutionary model. We then annotated all lineage-specific substitutions in terms of W → S bias and density on the chromosomes. Finally, we used the inferred substitutions to calculate a BDS score-a log odds ratio between substitution type and density-and assessed its statistical significance with Fisher's exact test. Applying this approach, we found significant BDS in the coding and noncoding sequence of human, mouse, dog, stickleback, fruit fly, and worm. We also observed a significant lack of W → S BDS in chicken and yeast. The BDS score varies between species and across the chromosomes within each species. It is most strongly correlated with different genomic features in different species, but a strong correlation with recombination rates is found in several species. Our results demonstrate that a W → S substitution bias in fast-evolving sequences is a widespread phenomenon. The patterns of BDS observed suggest that a recombination-associated process, such as GC-biased gene conversion, is involved in the production of the bias in many species, but the strength of the BDS likely depends on many factors, including genome stability, variability in recombination rate over time and across the genome, the frequency of meiosis, and the amount of outcrossing in each species. PMID:21670083

  8. 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.

  9. Chromosome rearrangements and transposable elements.

    Science.gov (United States)

    Lonnig, Wolf-Ekkehard; Saedler, Heinz

    2002-01-01

    There has been limited corroboration to date for McClintock's vision of gene regulation by transposable elements (TEs), although her proposition on the origin of species by TE-induced complex chromosome reorganizations in combination with gene mutations, i.e., the involvement of both factors in relatively sudden formations of species in many plant and animal genera, has been more promising. Moreover, resolution is in sight for several seemingly contradictory phenomena such as the endless reshuffling of chromosome structures and gene sequences versus synteny and the constancy of living fossils (or stasis in general). Recent wide-ranging investigations have confirmed and enlarged the number of earlier cases of TE target site selection (hot spots for TE integration), implying preestablished rather than accidental chromosome rearrangements for nonhomologous recombination of host DNA. The possibility of a partly predetermined generation of biodiversity and new species is discussed. The views of several leading transposon experts on the rather abrupt origin of new species have not been synthesized into the macroevolutionary theory of the punctuated equilibrium school of paleontology inferred from thoroughly consistent features of the fossil record. PMID:12429698

  10. Comparative Genomics of Interreplichore Translocations in Bacteria: A Measure of Chromosome Topology?

    Directory of Open Access Journals (Sweden)

    Supriya Khedkar

    2016-06-01

    Full Text Available 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.

  11. Comparative analysis of sex chromosomes in Leporinus species (Teleostei, Characiformes) using chromosome painting

    Science.gov (United States)

    2013-01-01

    Background The Leporinus genus, belonging to the Anostomidae family, is an interesting model for studies of sex chromosome evolution in fish, particularly because of the presence of heteromorphic sex chromosomes only in some species of the genus. In this study we used W chromosome-derived probes in a series of cross species chromosome painting experiments to try to understand events of sex chromosome evolution in this family. Results W chromosome painting probes from Leporinus elongatus, L. macrocephalus and L. obtusidens were hybridized to each others chromosomes. The results showed signals along their W chromosomes and the use of L. elongatus W probe against L. macrocephalus and L. obtusidens also showed signals over the Z chromosome. No signals were observed when the later aforementioned probe was used in hybridization procedures against other four Anostomidae species without sex chromosomes. Conclusions Our results demonstrate a common origin of sex chromosomes in L. elongatus, L. macrocephalus and L. obtusidens but suggest that the L. elongatus chromosome system is at a different evolutionary stage. The absence of signals in the species without differentiated sex chromosomes does not exclude the possibility of cryptic sex chromosomes, but they must contain other Leporinus W sequences than those described here. PMID:23822802

  12. 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

    Abstract 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. PMID:26753081

  13. 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.

  14. Identification of RAPD Marker for Chromosome 1D of Common Wheat

    Directory of Open Access Journals (Sweden)

    Imtiaz Ahmad Khan

    2010-04-01

    Full Text Available Development of genetically compensating nullisomic-tetrasomic and ditelosomic lines of commonwheat (Triticum aestivum L. have been widely used to construct high density genetic maps of homoeologouswheat chromosomes. During present research, easier, cheaper and quicker procedure of Polymerase ChainReaction (PCR was used to map Randomly Amplified Polymorphic DNA primers on chromosome 1D ofcommon wheat. Genomic DNA was isolated from two genetic stocks of wheat cultivar Chinese Spring viz;NT-1D1B and NT-2A2B. PCR were conducted using RAPD primers GLC-07 and GLC-11. RAPD primerGLC-11 amplified a polymorphic allele of approximately 500 bp, which was present in NT-2A2B (used aspositive control but was absent in NT-1D1B indicating that the locus is present on chromosome 1D of commonwheat. Hence this marker (GLC-11 can reliably be used to keep track of chromosome 1D of hexaploid wheat.

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

    DEFF Research Database (Denmark)

    Koch, J E; Kølvraa, S; Hertz, Jens Michael; Rasmussen, K; Gregersen, N; Fly, G F; Bolund, L A

    1990-01-01

    the C-band analysis, while at the same time to some extent replacing the Q-band analysis as well. The advantage of using in situ hybridization is mainly that it allows the very fast screening of a large number of metaphases. We illustrate this new application of the technique by using it for the......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 to...... 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....

  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).

    Science.gov (United States)

    Penitente, Manolo; Voltolin, Tatiana A; Senhorini, José A; Bortolozzi, Jehud; Foresti, Fausto; Porto-Foresti, Fábio

    2013-01-01

    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 k(B)=0.388 for the acrocentric type, a kB=0.507 for the metacentric type and a k(B)=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. PMID:24141415

  18. 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.

  19. 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.

  20. The peripheral chromosome scaffold, a novel structural component of mitotic chromosomes.

    Science.gov (United States)

    Sheval, Eugene V; Polyakov, Vladimir Y

    2008-06-01

    Using an original high-salt extraction protocol, we observed a novel chromosome substructure, referred to as the peripheral chromosome scaffold. This chromosome domain contained the perichromosomal layer proteins pKi-67, B23/nucleophosmin and fibrillarin, but no DNA fragments (i.e., the loop domain bases were not associated with the peripheral scaffold). Modern models of chromosome organization do not predict the existence of a peripheral chromosome scaffold domain, and thus our observations have conceptual implications for understanding chromosome architecture. PMID:18337132

  1. 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,

  2. Chromosome Studies in Patients with Polycythaemia Vera after Treatment with 32P

    International Nuclear Information System (INIS)

    The chromosomes of bone-marrow cells and blood lymphocytes of forty-six patients with polycythaemia vera were analysed to trace the sequence of events leading to the development of bone-marrow failure or 'leukaemia'. All except one of the patients had received radiophosphorus (32P). It might be expected that the yield of chromosomal aberrations of the two-break type (translocations etc.) from the low dose-rate beta radiation of 32P would be small. However, 'unstable' types of abnormality (dicentrics, fragments) and stable types (translocations, inversions, deletions) were observed in 6-25% of the blood lymphocytes; there was no evidence of clones of abnormal cells. In the majority of patients the bone marrow was predominantly normal diploid; occasional sporadic cells with 'stable' chromosomal abnormalities were seen in two-thirds of the cases, but 'unstable' aberrations were rare. In seven cases there were clones of cells characterised by deletions or translocations. All these chromosomal changes are probably radiation-induced. Clones of cells with a similar abnormality, an apparent deletion of one of the F-group chromosomes, were observed in the bone marrow in ten patients. Eight of these had received 32P and two busulphan. In two cases the clone appeared to develop after treatment. A similar anomaly has been reported in several cases of idiopathic sideroblastic anaemia who had not been irradiated. Progression into the leukaemic phase of the disease is associated in some cases with gross chromosomal abnormalities, such as shift of the stem line chromosome number and bizarre chromosome 'markers'. In other cases, some of whom have not been irradiated for several years, the chromosomal changes are less pronounced and may result from non-disjunctional gain of one or more chromosomes or chromosome loss. One case showed a step-by-step clonal evolution over a two-year period. None of the chromosomal abnormalities in the 'leukaemic' phase appear to be a direct result of

  3. 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

  4. 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....

  5. Substituting oil by electric power

    International Nuclear Information System (INIS)

    Parting from the development of primary energy use the author refers to the latest investigations and results presented on the 1980 World Energy Conference and with special regard to oil points out the threatening exhaustion of fossil energy resources. Maintaining the economic structure of the Federal Republic of Germany implies an orientation away from oil. Due to its flexible application technology and quasi-inexhaustible energy resources electric power may substantially contribute to oil substitution which as a matter of fact is of particular interest in connection with the heat market. Coal alone cannot substitute both oil and nuclear energy. Thus, the above postulates the use of the latter. Leaving nuclear energy inactive today will effect an increase in the demand for oil the negative consequences of which would weight heavily upon the anyhow unbalanced import/export ratio of the Federal Republic of Germany. (orig.)

  6. 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

  7. International Evidence on Sectoral Interfuel Substitution

    OpenAIRE

    Serletis, Apostolos; Timilsina, Govinda R.; Vasetsky, Olexandr

    2010-01-01

    This paper estimates interfuel substitution elasticities in selected developing and industrialized economies at the sector level. In doing so, it employs state-of-the-art techniques in microeconometrics, particularly the locally flexible normalized quadratic functional form, and provides evidence consistent with neoclassical microeconomic theory. The results indicate that the interfuel substitution elasticities are consistently below unity, revealing the limited ability to substitute between ...

  8. Substitutes for School Nurses in Illinois

    Science.gov (United States)

    Vollinger, Linda Jeno; Bergren, Martha Dewey; Belmonte-Mann, Frances

    2011-01-01

    The purpose of this descriptive study was to explore utilization of nurse substitutes in the school setting in Illinois. The literature described personnel who staff the school health office in the absence of the school nurse and the barriers to obtaining nurse substitutes. There were no empirical studies conducted on school nurse substitutes in…

  9. 40 CFR 721.3360 - Substituted ethanolamine.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted ethanolamine. 721.3360... Substances § 721.3360 Substituted ethanolamine. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted ethanolamine (PMN P-91-490)...

  10. 24 CFR 220.253 - Substitute mortgagors.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Substitute mortgagors. 220.253... Contract Rights and Obligations-Homes § 220.253 Substitute mortgagors. (a) Selling mortgagor. The mortgagee... the Commissioner's approval of a substitute mortgagor, as provided by this section. (b)...

  11. 24 CFR 221.252 - Substitute mortgagors.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Substitute mortgagors. 221.252... Cost Homes § 221.252 Substitute mortgagors. (a) Selling mortgagor. The mortgagee may effect the release... approval of a substitute mortgagor, as provided by this section. (b) Purchasing mortgagor. The...

  12. 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)...

  13. 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 and not...... and not correlated with auxin strength measured in the Avena coleoptile test....

  14. Substituting Quantum Entanglement for Communication

    OpenAIRE

    Cleve, Richard; Buhrman, Harry

    1997-01-01

    We show that quantum entanglement can be used as a substitute for communication when the goal is to compute a function whose input data is distributed among remote parties. Specifically, we show that, for a particular function among three parties (each of which possesses part of the function's input), a prior quantum entanglement enables one of them to learn the value of the function with only two bits of communication occurring among the parties, whereas, without quantum entanglement, three ...

  15. A Bifunctional Dimethylsulfoxide Substitute Enhances the Aqueous Solubility of Small Organic Molecules

    OpenAIRE

    Sprachman, Melissa M.; Wipf, Peter

    2012-01-01

    An oxetane-substituted sulfoxide has demonstrated potential as a dimethylsulfoxide substitute for enhancing the dissolution of organic compounds with poor aqueous solubilities. This sulfoxide may find utility in applications of library storage and biological assays. For the model compounds studied, significant solubility enhancements were observed using the sulfoxide as a cosolvent in aqueous media. Brine shrimp, breast cancer (MDA-MB-231), and liver cell line (HepG2) toxicity data for the ne...

  16. 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.

  17. Geometric realization for substitution tilings

    CERN Document Server

    Barge, Marcy

    2011-01-01

    Given an n-dimensional substitution whose associated linear expansion is unimodular and hyperbolic, we use elements of the one-dimensional integer \\v{C}ech cohomology of the associated tiling space to construct a finite-to-one semi-conjugacy, called geometric realization, between the substitution induced dynamics and an invariant set of a hyperbolic toral automorphism. If the linear expansion satisfies a Pisot family condition and the rank of the module of generalized return vectors equals the generalized degree of the linear expansion, the image of geometric realization is the entire torus and coincides with the map onto the maximal equicontinuous factor of the translation action on the tiling space. We are led to formulate a higher-dimensional generalization of the Pisot Substitution Conjecture: If the linear expansion satisfies the Pisot family condition and the rank of the one-dimensional cohomology of the tiling space equals the generalized degree of the linear expansion, then the translation action on t...

  18. Radiation induced chromosome instability in human fibroblasts

    International Nuclear Information System (INIS)

    Evidence has been arising that some biological effects can manifest many cell divisions after irradiation. We have demonstrated that de novo chromosome instability can be detected 10- 15 mean population doubling after heavy ion irradiations. This chromosome instability is characterized by end to end fusions between specific chromosomes. The specificity of the instability may differ from one donor to another but for the same donor, the same instability should be observed after irradiation, during the senescence process and after SV40 transfection (before crisis). In irradiated primary culture fibroblasts, the expression of the delayed chromosomal instability lasts for several cell divisions without inducing cell death. Several rounds of fusions- breakage-fusions can be performed and unbalanced clones emerge (gain or loss of chromosomes with the shorter telomeres would become unstable first.. The difference in the chromosomal instability among donors could be due to a polymorphism in telomere lengths. This could induce large variation in long term response to irradiation among individuals. (author)

  19. Method of lines for parabolic stochastic functional partial differential equations

    OpenAIRE

    Maria Ziemlańska

    2014-01-01

    We approximate parabolic stochastic functional differential equations substituting the derivatives in the space variable by finite differences. We prove the stability of the method of lines corresponding to a parabolic SPDE driven by Brownian motion.

  20. Method of lines for parabolic stochastic functional partial differential equations

    Directory of Open Access Journals (Sweden)

    Maria Ziemlańska

    2014-01-01

    Full Text Available We approximate parabolic stochastic functional differential equations substituting the derivatives in the space variable by finite differences. We prove the stability of the method of lines corresponding to a parabolic SPDE driven by Brownian motion.

  1. Common dynamics of two Pisot substitutions with the same incidence matrix

    CERN Document Server

    Sellami, Tarek

    2010-01-01

    The matrix of a substitution is not sufficient to completely determine the dynamics associated, even in simplest cases since there are many words with the same abelianization. In this paper we study the common points of the canonical broken lines associated to two different Pisot irreducible substitutions $\\sigma_1$ and $\\sigma_2$ having the same incidence matrix. We prove that if 0 is inner point to the Rauzy fractal associated to $\\sigma_1$ these common points can be generated with a substitution on an alphabet of so-called "balanced blocks".

  2. 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

  3. 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

  4. 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...

  5. Novel Gene Acquisition on Carnivore Y Chromosomes

    OpenAIRE

    Murphy, William J.; A J Pearks Wilkerson; Terje Raudsepp; Richa Agarwala; Schäffer, Alejandro A.; Roscoe Stanyon; Chowdhary, Bhanu P

    2006-01-01

    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...

  6. Identification of bacterial cells by chromosomal painting.

    OpenAIRE

    Lanoil, B. D.; Giovannoni, S J

    1997-01-01

    Chromosomal painting is a technique for the microscopic localization of genetic material. It has been applied at the subcellular level to identify regions of eukaryotic chromosomes. Here we describe the development of bacterial chromosomal painting (BCP), a related technology for the identification of bacterial cells. Purified genomic DNAs from six bacterial strains were labeled by nick translation with the fluorochrome Fluor-X, Cy3, or Cy5. The average size of the labeled fragments was ca. 5...

  7. Holoprosencephaly due to Numeric Chromosome Abnormalities

    OpenAIRE

    Solomon, Benjamin D.; Rosenbaum, Kenneth N.; Meck, Jeanne M.; Muenke, Maximilian

    2010-01-01

    Holoprosencephaly (HPE) is the most common malformation of the human forebrain. When a clinician identifies a patient with HPE, a routine chromosome analysis is often the first genetic test sent for laboratory analysis in order to assess for a structural or numerical chromosome anomaly. An abnormality of chromosome number is overall the most frequently identified etiology in a patient with HPE. These abnormalities include trisomy 13, trisomy 18, and triploidy, though several others have been ...

  8. CHROMOSOMAL ABNORMALITIES IN PATIENTS WITH RECURRENT MISCARRIAGE

    OpenAIRE

    Daniela Mierla; Viorica Radoi; Veronica Stoian

    2012-01-01

    Chromosomal abnormalities are involved in the etiology of recurrent spontaneous pregnancy loss and sub-fertility. The purpose of this study was to determine the frequency and contribution of chromosomal abnormalities in recurrent miscarriages. The results obtained and literature review are helpful in understanding the importance of cytogenetics analysis of female infertility. To investigate the distribution of chromosomal abnormalities in the Romanian population with recurrent miscarriage, ka...

  9. How does DNA break during chromosomal translocations?

    OpenAIRE

    Nambiar, Mridula; Raghavan, Sathees C.

    2011-01-01

    Chromosomal translocations are one of the most common types of genetic rearrangements and are molecular signatures for many types of cancers. They are considered as primary causes for cancers, especially lymphoma and leukemia. Although many translocations have been reported in the last four decades, the mechanism by which chromosomes break during a translocation remains largely unknown. In this review, we summarize recent advances made in understanding the molecular mechanism of chromosomal t...

  10. 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.

  11. Advances in plant chromosome genomics

    Czech Academy of Sciences Publication Activity Database

    Doležel, Jaroslav; Vrána, Jan; Cápal, Petr; Kubaláková, Marie; Burešová, Veronika; Šimková, Hana

    2014-01-01

    Roč. 32, č. 1 (2014), s. 122-136. ISSN 0734-9750 R&D Projects: GA ČR GAP501/10/1740; GA ČR GAP501/10/1778; GA ČR GBP501/12/G090; GA MŠk(CZ) LO1204 Grant ostatní: GA MŠk(CZ) ED0007/01/01 Institutional support: RVO:61389030 Keywords : BAC library * Chromosome sorting * Cytogenetics Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 9.015, year: 2014

  12. Multiple chromosomes of Azotobacter vinelandii.

    OpenAIRE

    1989-01-01

    The number of copies of the genes leuB, nifH, nifD, and nifK per cell of Azotobacter vinelandii has been determined to be about 80. A beta-lactamase gene was integrated into the A. vinelandii chromosome by single-point crossover. Subsequently, we have been able to detect nearly 80 copies of this beta-lactamase gene per cell of A. vinelandii when cultured for a large number of generations in the presence of ampicillin. The multiple copies of the beta-lactamase gene do not seem to be present on...

  13. Chromosome banding in Amphibia. XXIV. The B chromosomes of Gastrotheca espeletia (Anura, Hylidae).

    Science.gov (United States)

    Schmid, M; Ziegler, C G; Steinlein, C; Nanda, I; Haaf, T

    2002-01-01

    The mitotic chromosomes of an Ecuadorian population of the marsupial frog Gastrotheca espeletia were analyzed by means of banding techniques and fluorescence in situ hybridization. This species is characterized by unusual supernumerary (B) chromosomes. The maximum number of B chromosomes is 9 and they occur in three different morphological types. Banding analyses show that the B chromosomes are completely heterochromatic, consist of AT base pair-rich repeated DNA sequences, replicate their DNA in very late S-phase of the cell cycle, and are probably derived from a centromeric or paracentromeric region of a standard (A) chromosome. Exceptionally, the B chromosomes carry 18S + 28S ribosomal RNA genes and the conserved vertebrate telomeric DNA sequence appears to be underrepresented. Flow cytometric measurements of the nuclear DNA content differentiate between individuals with different numbers of B chromosomes. Significantly more B chromosomes are present in female than in male animals. PMID:12438715

  14. Giemsa C-banding of Barley Chromosomes. IV. Chromosomal Constitution of Autotetraploid Barley

    DEFF Research Database (Denmark)

    Linde-Laursen, Ib

    1984-01-01

    homologues of each of the chromosomes. The aneuploid C2--seedlings were fairly equally distributed on hypo-and hyperploids, and on the seven chromosome groups. This suggests that a particular chromosome is lost or gained at random in gametes and embryos. The 11 C3--seedlings comprised seven true euploids......The progeny of an autotetraploid barley plant (C1) consisted of 45 tetraploids and 33 aneuploids. Giemsa C-banding was used to identify each of the chromosomes in 20 euploid and 31 aneuploid C2--seedlings, and in 11 C3--offspring of aneuploid C2--plants. The euploid C2--seedlings all had four......, one seedling with 2n=28 having an extra chromosome 6 and missing one chromosome 3, and three seedlings with 2n=29. The chromosomal composition of aneuploid C3--seedlings did not reflect that of their aneuploid C2--parents with respect to missing or extra chromosomes. Two hypohexaploid C2--seedlings...

  15. Microtubule detyrosination guides chromosomes during mitosis

    OpenAIRE

    Barisic, Marin; Silva e Sousa, Ricardo; Tripathy, Suvranta K.; Magiera, Maria M.; Zaytsev, Anatoly V.; Pereira, Ana L.; Janke, Carsten; Grishchuk, Ekaterina L.; Maiato, Helder

    2015-01-01

    Before chromosomes segregate into daughter cells they align at the mitotic spindle equator, a process known as chromosome congression. CENP-E/Kinesin-7 is a microtubule plus-end-directed kinetochore motor required for congression of pole-proximal chromosomes. Because the plus-ends of many astral microtubules in the spindle point to the cell cortex, it remains unknown how CENP-E guides pole-proximal chromosomes specifically towards the equator. Here we found that congression of pole-proximal c...

  16. Exceptional Complex Chromosomal Rearrangements in Three Generations

    Directory of Open Access Journals (Sweden)

    Hannie Kartapradja

    2015-01-01

    Full Text Available We report an exceptional complex chromosomal rearrangement (CCR found in three individuals in a family that involves 4 chromosomes with 5 breakpoints. The CCR was ascertained in a phenotypically abnormal newborn with additional chromosomal material on the short arm of chromosome 4. Maternal karyotyping indicated that the mother carried an apparently balanced CCR involving chromosomes 4, 6, 11, and 18. Maternal transmission of the derivative chromosome 4 resulted in partial trisomy for chromosomes 6q and 18q and a partial monosomy of chromosome 4p in the proband. Further family studies found that the maternal grandmother carried the same apparently balanced CCR as the proband’s mother, which was confirmed using the whole chromosome painting (WCP FISH. High resolution whole genome microarray analysis of DNA from the proband’s mother found no evidence for copy number imbalance in the vicinity of the CCR translocation breakpoints, or elsewhere in the genome, providing evidence that the mother’s and grandmother’s CCRs were balanced at a molecular level. This structural rearrangement can be categorized as an exceptional CCR due to its complexity and is a rare example of an exceptional CCR being transmitted in balanced and/or unbalanced form across three generations.

  17. Chromosome heteromorphisms in the Japanese, 3

    International Nuclear Information System (INIS)

    The type and frequency of chromosome variants detected by the C-staining method were ascertained in 1,857 individuals residing in Hiroshima. The most frequent heteromorphic variant was the total inversion of the C-band in chromosome 9 found in 27 individuals (1.45%). The total inversion of the C-band in chromosome 1 was not seen in this sample, but the partial inversion of the C-band in chromosome 1 was found in 18 persons (0.97%). Partial inversion was also detected in the C-band in chromosome 9 in 22 individuals (1.18%). In chromosome 16, neither total nor partial inversion of the C-band was observed in the present study. The frequencies of chromosomes 1, 9, and 16 with a very large C-band were 0.70%, 0.22%, and 0.54%, respectively. Aside from these (1, 9, and 16) a very large C-band was found occasionally in chromosomes 4, 5, 6, 11, 12, 14, and 15, and an unusual insertion of the Y chromosome was observed. A total of 128 C-band variants (6.89%) was found in the 1,857 Hiroshima residents. (author)

  18. 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. PMID:23622175

  19. Chromosomal aberrations in ore miners of Slovakia

    International Nuclear Information System (INIS)

    A pilot study was performed in which the incidence of chromosomal aberrations in lymphocytes of miners in ore mines located in Central Slovakia was monitored and related to lifetime underground radon exposure and to lifetime smoking. The conclusions drawn from the results of the study were as follows: the counts of chromosomal aberrations in lymphocytes of miners were significantly higher than in an age matched control group of white-collar staff; the higher counts of chromosomal aberrations could be ascribed to underground exposure of miners and to smoking; a dependence of chromosomal aberration counts on the exposure to radon could not be assessed. (A.K.)

  20. Explicit Substitutions for Contextual Type Theory

    CERN Document Server

    Abel, Andreas; 10.4204/EPTCS.34.3

    2010-01-01

    In this paper, we present an explicit substitution calculus which distinguishes between ordinary bound variables and meta-variables. Its typing discipline is derived from contextual modal type theory. We first present a dependently typed lambda calculus with explicit substitutions for ordinary variables and explicit meta-substitutions for meta-variables. We then present a weak head normalization procedure which performs both substitutions lazily and in a single pass thereby combining substitution walks for the two different classes of variables. Finally, we describe a bidirectional type checking algorithm which uses weak head normalization and prove soundness.

  1. Diversity of sex chromosome abnormalities in a cohort of 95 Indonesian patients with monosomy X

    Directory of Open Access Journals (Sweden)

    Kartapradja Hannie

    2011-10-01

    Full Text Available Abstract Background Monosomy × or 45,X is a cytogenetic characteristic for Turner syndrome. This chromosome anomaly is encountered in around 50% of cases, but wide variations of other anomalies have been found. This report is to describe the cytogenetic characteristics of 45,X individuals. To the best of our knowledge, there were no large series of 45,X cases has been reported from Indonesia. Results Ninety five cases with 45,X cell line found, of which 60 were detected by karyotyping, 4 by FISH for sex chromosomes, and 31 by both karyotyping and FISH. Using karyotyping 37 out of 91 cases(40.6% were identified as 45,X individuals, while cases who underwent FISH only 4 out of 35 cases (11.4% showed 45,X result, resulting in total of 39 45,X cases (41.1%, and the rest 56 (58.9% cases are mosaic. Among these cases, 21 out of 95 (22.1% have Y or part of Y as the second or third sex chromosome in their additional cell lines. Result discrepancies revealed in 22 out of 31 cases who underwent both FISH and karyotyping, of which 7 showed normal 46,XX or 46,XY karyotypes, but by FISH, additional monosomy × cell line was found. Most of the cases were referred at the age of puberty (8-13 years old or after that (14-18 years old, 31 and 21 cases respectively, and there were 14 cases were sent in adulthood. Conclusion Wide variations of sex chromosome aberrations have been detected using the combination of conventional cytogenetic and FISH, including detection of low level of mosaicism and Y-chromosome fragments. Result discrepancies using both techniques were found in 22/31 cases, and in order to obtain a more details of sex chromosome constitution of individuals with 45,X cell line both FISH and karyotyping should be carried out simultaneously.

  2. Transformation with DNA from 5-azacytidine-reactivated X chromosomes.

    OpenAIRE

    Venolia, L; Gartler, S M; Wassman, E R; Yen, P.; Mohandas, T; Shapiro, L J

    1982-01-01

    It has been shown that 5-azacytidine (5-Aza-Cyd) can reactivate genes on the inactive human X chromosome. It is assumed that the 5-Aza-Cyd acts by causing demethylation of the DNA at specific sites, but this cannot be demonstrated directly without a cloned probe. Instead, we have utilized the technique of DNA-mediated transformation to show that the 5-Aza-Cyd-induced reactivation occurs at the DNA level. DNAs from various mouse-human or hamster-human hybrid cell lines, deficient for mouse or ...

  3. A Dysmorphic Child with a Pericentric Inversion of Chromosome 8

    Directory of Open Access Journals (Sweden)

    Venkateshwari Ananthapur

    2012-01-01

    Full Text Available An 8-year-old boy was referred to our institute with dysmorphic features such as mild lupus, micrognathia, low hair line, hypoplasia, hemi atrophy of left side of the face, abnormal size of ears, hypothenar, hypoplasia of chin, and tongue tie. MRI scan was found to be normal and EEG suggestive of generalized seizure disorder. Cytogenetic evaluation of the proband revealed a pericentric inversion of chromosome 8 with 46, XY, and inv 8 (p11.2; q21.2 karyotype.

  4. A dysmorphic child with a pericentric inversion of chromosome 8.

    Science.gov (United States)

    Ananthapur, Venkateshwari; Avvari, Srilekha; Madireddi, Sujatha; Nallari, Pratibha; Akka, Jyothy

    2012-01-01

    An 8-year-old boy was referred to our institute with dysmorphic features such as mild lupus, micrognathia, low hair line, hypoplasia, hemi atrophy of left side of the face, abnormal size of ears, hypothenar, hypoplasia of chin, and tongue tie. MRI scan was found to be normal and EEG suggestive of generalized seizure disorder. Cytogenetic evaluation of the proband revealed a pericentric inversion of chromosome 8 with 46, XY, and inv 8 (p11.2; q21.2) karyotype. PMID:22606536

  5. Chromosomally integrated human herpesvirus 6: questions and answers

    OpenAIRE

    Pellett, Philip E.; Ablashi, Dharam V.; Ambros, Peter F.; Agut, Henri; Caserta, Mary T.; Descamps, Vincent; Flamand, Louis; Gautheret-Dejean, Agnès; Hall, Caroline B.; Kamble, Rammurti T.; Kuehl, Uwe; Lassner, Dirk; Lautenschlager, Irmeli; Loomis, Kristin S.; Luppi, Mario

    2011-01-01

    SUMMARY Chromosomally integrated human herpesvirus 6 (ciHHV-6) is a condition in which the complete HHV-6 genome is integrated into the host germ line genome and is vertically transmitted in a Mendelian manner. The condition is found in less than 1% of controls in the USA and UK, but has been found at a somewhat higher prevalence in transplant recipients and other patient populations in several small studies. HHV-6 levels in whole blood that exceed 5.5 log10 copies/ml are strongly suggestive ...

  6. MLD Relations of Pisot Substitution Tilings

    CERN Document Server

    Gähler, Franz

    2010-01-01

    We consider 1-dimensional, unimodular Pisot substitution tilings with three intervals, and discuss conditions under which pairs of such tilings are locally isomorhphic (LI), or mutually locally derivable (MDL). For this purpose, we regard the substitutions as homomorphisms of the underlying free group with three generators. Then, if two substitutions are conjugated by an inner automorphism of the free group, the two tilings are LI, and a conjugating outer automorphism between two substitutions can often be used to prove that the two tilings are MLD. We present several examples illustrating the different phenomena that can occur in this context. In particular, we show how two substitution tilings can be MLD even if their substitution matrices are not equal, but only conjugate in $GL(n,\\mathbb{Z})$. We also illustrate how the (in our case fractal) windows of MLD tilings can be reconstructed from each other, and discuss how the conjugating group automorphism affects the substitution generating the window boundar...

  7. 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.

  8. Increased chromosome radiosensitivity during pregnancy

    International Nuclear Information System (INIS)

    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

  9. Retrospective dosimetry by chromosomal analysis

    International Nuclear Information System (INIS)

    The joint EU/CIS project ECP-6, was set up to examine whether cytogenetic dosimetry is possible for persons irradiated years previously at Chernobyl. The paper describes the possibility of achieving this by the examination of blood lymphocytes for unstable and stable chromosome aberrations; dicentrics and translocations. Emphasis was placed on the relatively new fluorescence in situ hybridization (FISH) method for rapid screening for stable translocations. In a collaborative experiment in vitro dose response calibration curves for dicentrics and FISH were produced with gamma radiation over the range 0-1.0 Gy. A pilot study of about 60 liquidators with registered doses ranging from 0-300 mSv was undertaken to determine whether the chromosomal methods may verify the recorded doses. It was concluded that the dicentric is no longer valid as a measured endpoint. Translocations may be used to verify early dosimetry carried out on highly irradiated persons. For the vast majority of lesser exposed subjects FISH is impractical as an individual dosimeter; it may have some value for comparing groups of subjects

  10. Chromosomal replicons of higher plants

    International Nuclear Information System (INIS)

    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

  11. 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.

  12. The X chromosome of monotremes shares a highly conserved region with the eutherian and marsupial X chromosomes despite the absence of X chromosome inactivation

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J.M.; Spencer, J.A.; Graves, J.A.M. (La Trobe Univ., Bundoora, Victoria (Australia)); Riggs, A.D. (Beckman Inst., Duarte, CA (USA))

    1990-09-01

    Eight genes, located on the long arm of the human X chromosome and present on the marsupial X chromosome, were mapped by in situ hybridization to the chromosomes of the platypus Ornithorhynchus anatinus, one of the three species of monotreme mammals. All were located on the X chromosome. The authors conclude that the long arm of the human X chromosome represents a highly conserved region that formed part of the X chromosome in a mammalian ancestor at least 150 million years ago. Since three of these genes are located on the long arm of the platypus X chromosome, which is G-band homologous to the Y chromosome and apparently exempt from X chromosome inactivation, the conservation of this region has evidently not depended on isolation by X-Y chromosome differentiation and X chromosome inactivation.

  13. Chromosome analysis of early embryonic mortality in layer and broiler chickens.

    Science.gov (United States)

    Thorne, M H; Collins, R K; Sheldon, B L

    1991-09-01

    1. Twenty-three lines of chickens, obtained from grandparent stocks of 4 Australian breeding companies, were analysed to determine the incidence of early embryonic mortality attributable to chromosome abnormalities. The lines included 10 layer strains, consisting of 6 White Leghorn, 2 New Hampshire and 2 Australorp lines, and 13 broiler lines. 2. A total of 10,730 eggs was examined after 3 d incubation; of these 9746 (90.8%) were fertile. Abortive embryonic development was observed in 1379 (14.1%) of the fertile eggs. This consisted of 952 (69.0%) dead and dying embryos, including 646 malformed and 427 (31.0%) membranes without embryos. 3. Early embryonic mortality was found to vary from 9.8 to 26.8% (average 16.4%) in broiler lines and from 8.0 to 27.9% (average 11.9%) in layer lines. 4. Among 898 abortive embryos analysed, 112 had abnormal chromosomes consisting of 27 haploids, 38 haploid-euploids, 24 triploids, 16 diploid-polyploids, 4 aneuploids, 2 tetraploids and 1 translocation. 5. In broilers and layers respectively, chromosome abnormalities were responsible for 4.4 to 28.1% (average 11.8%) and 7.4 to 25.0% (average 13.4%) of the early embryonic mortality. 6. The overall frequency of chromosome abnormalities in all fertile eggs varied from 0.7 to 3.7% for the broiler lines and 0.7 to 3.4% for the layer lines. PMID:1933445

  14. Down's/Turner's mosaicism. Double aneuploidy as a rare cause of missed prenatal diagnosis of chromosomal abnormality.

    OpenAIRE

    MacFaul, R; Turner, T.; Mason, M. K.

    1981-01-01

    Two babies with Down's/Turner's mosaic karyotype are reported. In each, because of advanced maternal age, chromosomal analysis had been carried out on the fluid obtained by amniocentesis in early pregnancy. Only the 46,X+ 21 cell line grew in the specimens and the extra 21 chromosome was wrongly identified as a Y chromosome, so that the fetus was thought to have a normal male karyotype, 46,XY. At birth both babies were phenotypically female with features predominantly of Down's syndrome and t...

  15. Microcell-Mediated Chromosome Transfer Identifies EPB41L3 as a Functional Suppressor of Epithelial Ovarian Cancers

    OpenAIRE

    Dimitra Dafou; Barbara Grun; John Sinclair; Kate Lawrenson; Benjamin, Elizabeth C; Estrid Hogdall; Susanne Kruger-Kjaer; Lise Christensen; Sowter, Heidi M.; Ahmed Al-Attar; Richard Edmondson; Stephen Darby; Andrew Berchuck; Laird, Peter W; C. Leigh Pearce

    2010-01-01

    We used a functional complementation approach to identify tumor-suppressor genes and putative therapeutic targets for ovarian cancer. Microcell-mediated transfer of chromosome 18 in the ovarian cancer cell line TOV21 G induced in vitro and in vivo neoplastic suppression. Gene expression microarray profiling in TOV21 +19 hybrids identified 14 candidate genes on chromosome 18 that were significantly overexpressed and therefore associated with neoplastic suppression. Further analysis of messenge...

  16. 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.

  17. Chromosomal painting and ZW sex chromosomes differentiation in Characidium (Characiformes, Crenuchidae)

    Science.gov (United States)

    2011-01-01

    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. PMID:21787398

  18. Cytogenetic characteristics and their variability in mice lines BALB/c and C57BL/6

    International Nuclear Information System (INIS)

    Mice lines BALB/c and C57BL/6 differ by the frequency of chromosome aberrations in morrow bone cells. The comparative analysis of the variabilities of a number of cytogenetic characteristics (intra chromosome defects, aneu- and polyploidy, mitotic index, micro nuclear test) in various age groups, season investigations, under influence of radio pollution on these lines is carried out. The least variabilities in both lines were revealed in chromosome aberrations and asynchronous chromatide divisions. The main interline distinctions are observed in the dynamics of polyploidy and in the fraction of mono nucleus lymphocytes with micronuclei and aneuploidy cells

  19. Microcell-mediated transfer of a single human chromosome complements xeroderma pigmentosum group A fibroblasts

    International Nuclear Information System (INIS)

    Chromosomes from an immortalized aneuploid human fibroblast cell line were randomly tagged with the selectable marker neo by transfection with the plasmid pSV2neo. Somatic cell fusions between transfected human cells and mouse A9 cells generated pools of G418-resistant human-mouse hybrid clones containing various numbers of human chromosomes. Microcell-mediated chromosome transfer from the hybrid pools to xeroderma pigmentosum complementation group A (XP-A) cells in culture and selection for G418-resistant colonies resulted in the identification of XP cells with enhanced resistance to ultraviolet radiation. Screening of subclones from selected pools of human-mouse hybrids facilitated the identification of hybrids containing a single neo-tagged human chromosome. Transfer of this chromosome to XP-A cells (but not to XP-F or XP-C cells) results in enhanced resistance to ultraviolet light and enhanced excision repair capacity. The identification of a single human chromosome that complements the phenotype of XP-A cells in culture provides the potential for genetic mapping of the complementing gene and for its isolation by molecular cloning

  20. 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.

  1. Proteomics Analysis with a Nano Random Forest Approach Reveals Novel Functional Interactions Regulated by SMC Complexes on Mitotic Chromosomes.

    Science.gov (United States)

    Ohta, Shinya; Montaño-Gutierrez, Luis F; de Lima Alves, Flavia; Ogawa, Hiromi; Toramoto, Iyo; Sato, Nobuko; Morrison, Ciaran G; Takeda, Shunichi; Hudson, Damien F; Rappsilber, Juri; Earnshaw, William C

    2016-08-01

    Packaging of DNA into condensed chromosomes during mitosis is essential for the faithful segregation of the genome into daughter nuclei. Although the structure and composition of mitotic chromosomes have been studied for over 30 years, these aspects are yet to be fully elucidated. Here, we used stable isotope labeling with amino acids in cell culture to compare the proteomes of mitotic chromosomes isolated from cell lines harboring conditional knockouts of members of the condensin (SMC2, CAP-H, CAP-D3), cohesin (Scc1/Rad21), and SMC5/6 (SMC5) complexes. Our analysis revealed that these complexes associate with chromosomes independently of each other, with the SMC5/6 complex showing no significant dependence on any other chromosomal proteins during mitosis. To identify subtle relationships between chromosomal proteins, we employed a nano Random Forest (nanoRF) approach to detect protein complexes and the relationships between them. Our nanoRF results suggested that as few as 113 of 5058 detected chromosomal proteins are functionally linked to chromosome structure and segregation. Furthermore, nanoRF data revealed 23 proteins that were not previously suspected to have functional interactions with complexes playing important roles in mitosis. Subsequent small-interfering-RNA-based validation and localization tracking by green fluorescent protein-tagging highlighted novel candidates that might play significant roles in mitotic progression. PMID:27231315

  2. 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 that...

  3. Chromosome number9 specific repetitive DNA sequence

    International Nuclear Information System (INIS)

    Human repetitive DNA libraries have been constructed and various recombinant DNA clones isolated that are likely candidates for chromosome specific sequences. The first clone tested (pHuR 98; plasmid human repeat 98) was biotinylated and hybridized to human chromosomes in situ. The hybridized recombinant probe was detected with fluoresceinated avidin, and chromosomes were counter-stained with either propidium iodide or distamycin-DAPI. Specific hybridization to chromosome band 9q1 was obtained. The localization was confirmed by hybridizing radiolabeled pHuR 98 DNA to human chromosomes sorted by flow cytometry. Various methods, including orthogonal field pulsed gel electrophoresis analysis indicate that 75 kilobase blocks of this sequence are interspersed with other repetitive DNA sequences in this chromosome band. This study is the first to report a human repetitive DNA sequence uniquely localized to a specific chromosome. This clone provides an easily detected and highly specific chromosomal marker for molecular cytogenetic analyses in numerous basic research and clinical studies

  4. Chromosomal characterization of Pseudonannolene strinatii (Spirostreptida, Pseudonannolenidae

    Directory of Open Access Journals (Sweden)

    Kleber Agari Campos

    2004-03-01

    Full Text Available The chromosomes of the cave millipede Pseudonannolene strinatii Mauriès, 1974 were investigated. The diploid chromosome number was found to be 2n=16, XX/XY; the C-banding technique revealed a large amount of heterochromatin while the silver staining technique (Ag-NOR evidenced the presence of heteromorphism of the NORs in some cells.

  5. 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.

  6. Mechanisms of Chromosome Number Evolution in Yeast

    Science.gov (United States)

    Gordon, Jonathan L.; Byrne, Kevin P.; Wolfe, Kenneth H.

    2011-01-01

    The whole-genome duplication (WGD) that occurred during yeast evolution changed the basal number of chromosomes from 8 to 16. However, the number of chromosomes in post-WGD species now ranges between 10 and 16, and the number in non-WGD species (Zygosaccharomyces, Kluyveromyces, Lachancea, and Ashbya) ranges between 6 and 8. To study the mechanism by which chromosome number changes, we traced the ancestry of centromeres and telomeres in each species. We observe only two mechanisms by which the number of chromosomes has decreased, as indicated by the loss of a centromere. The most frequent mechanism, seen 8 times, is telomere-to-telomere fusion between two chromosomes with the concomitant death of one centromere. The other mechanism, seen once, involves the breakage of a chromosome at its centromere, followed by the fusion of the two arms to the telomeres of two other chromosomes. The only mechanism by which chromosome number has increased in these species is WGD. Translocations and inversions have cycled telomere locations, internalizing some previously telomeric genes and creating novel telomeric locations. Comparison of centromere structures shows that the length of the CDEII region is variable between species but uniform within species. We trace the complete rearrangement history of the Lachancea kluyveri genome since its common ancestor with Saccharomyces and propose that its exceptionally low level of rearrangement is a consequence of the loss of the non-homologous end joining (NHEJ) DNA repair pathway in this species. PMID:21811419

  7. 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. PMID:27263828

  8. Physical map of the Bacillus cereus chromosome.

    OpenAIRE

    Kolstø, A B; Grønstad, A; Oppegaard, H

    1990-01-01

    A physical map of the Bacillus cereus chromosome has been constructed by aligning 11 NotI fragments, ranging in size from 200 to 1,300 kilobases. The size of the chromosome is about 5.7 megabases. This is the first Bacillus genome of which a complete physical map has been described.

  9. Compositions for chromosome-specific staining

    Science.gov (United States)

    Gray, Joe W.; Pinkel, Daniel

    1998-01-01

    Methods and compositions for staining based upon nucleic acid sequence that employ nucleic acid probes are provided. Said methods produce staining patterns that can be tailored for specific cytogenetic analyses. Said probes are appropriate for in situ hybridization and stain both interphase and metaphase chromosomal material with reliable signals. The nucleic acid probes are typically of a complexity greater than 50 kb, the complexity depending upon the cytogenetic application. Methods are provided to disable the hybridization capacity of shared, high copy repetitive sequences and/or remove such sequences to provide for useful contrast. Still further methods are provided to produce chromosome-specific staining reagents which are made specific to the targeted chromosomal material, which can be one or more whole chromosomes, one or more regions on one or more chromosomes, subsets of chromosomes and/or the entire genome. Probes and test kits are provided for use in tumor cytogenetics, in the detection of disease related loci, in analysis of structural abnormalities, such as translocations, and for biological dosimetry. Further, methods and prenatal test kits are provided to stain targeted chromosomal material of fetal cells, including fetal cells obtained from maternal blood. Still further, the invention provides for automated means to detect and analyse chromosomal abnormalities.

  10. 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.

  11. Mapping of human chromosomal regions related to neoplasia: evidence from chromosomes 1 and 17

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, J.D.

    1977-12-01

    In clonal aberrations leading to an excess or partial excess of chromosome I, trisomy for bands 1q25-1q32 was noted in the myeloid cells from all of 34 patients who had various disorders such as acute leukemia, polycythemia vera, and myelofibrosis. This was not the result of a particularly fragile site in that region of the chromosome because the break points in reciprocal translocations that involve it occurred almost exclusively in the short arm. Two consistent rearrangements that have been observed in chromosome 17 produced either duplication of the entire long arm or a translocation of the distal portion of the long arm to chromosome 15. The nonrandom chromosomal changes found in hematologic disorders can now be correlated with the gene loci on these chromosomes or chromosomal segments. Seventy-five genes related to various metabolic enzymes have been mapped; it may be significant that chromosomes carrying gene loci related to nucleic acid metabolism are more frequently involved in hematologic disorders (and other malignancies as well) than are gene loci related to intermediary or carbohydrate metabolism. Furthermore, the known virus-human chromosome associations are closely correlated with the chromosomes affected in hematologic disorders. If one of the effects of carcinogens (including viruses) is to activate genes that regulate host cell DNA synthesis, and if translocations or duplications of specific chromosomal segments produce the same effect, then either of these mechanisms might provide the affected cell with a proliferative advantage.

  12. 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.

  13. Genetic conflict and sex chromosome evolution

    Science.gov (United States)

    Meiklejohn, Colin D; Tao, Yun

    2009-01-01

    Chromosomal sex determination systems create the opportunity for the evolution of selfish genetic elements that increase the transmission of one sex chromosome at the expense of its homolog. Because such selfish elements on sex chromosomes can reduce fertility and distort the sex ratio of progeny, unlinked suppressors are expected to evolve, bringing different regions of the genome into conflict over the meiotic transmission of the sex chromosomes. Here we argue that recurrent genetic conflict over sex chromosome transmission is an important evolutionary force that has shaped a wide range of seemingly disparate phenomena including the epigenetic regulation of genes expressed in the germline, the distribution of genes in the genome, and the evolution of hybrid sterility between species. PMID:19931208

  14. 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.

  15. 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.

  16. Y-chromosome evolution: emerging insights into processes of Y-chromosome degeneration.

    Science.gov (United States)

    Bachtrog, Doris

    2013-02-01

    The human Y chromosome is intriguing not only because it harbours the master-switch gene that determines gender but also because of its unusual evolutionary history. The Y chromosome evolved from an autosome, and its evolution has been characterized by massive gene decay. Recent whole-genome and transcriptome analyses of Y chromosomes in humans and other primates, in Drosophila species and in plants have shed light on the current gene content of the Y chromosome, its origins and its long-term fate. Furthermore, comparative analysis of young and old Y chromosomes has given further insights into the evolutionary and molecular forces triggering Y-chromosome degeneration and into the evolutionary destiny of the Y chromosome. PMID:23329112

  17. Evolutionary history of novel genes on the tammar wallaby Y chromosome: Implications for sex chromosome evolution.

    Science.gov (United States)

    Murtagh, Veronica J; O'Meally, Denis; Sankovic, Natasha; Delbridge, Margaret L; Kuroki, Yoko; Boore, Jeffrey L; Toyoda, Atsushi; Jordan, Kristen S; Pask, Andrew J; Renfree, Marilyn B; Fujiyama, Asao; Graves, Jennifer A Marshall; Waters, Paul D

    2012-03-01

    We report here the isolation and sequencing of 10 Y-specific tammar wallaby (Macropus eugenii) BAC clones, revealing five hitherto undescribed tammar wallaby Y genes (in addition to the five genes already described) and several pseudogenes. Some genes on the wallaby Y display testis-specific expression, but most have low widespread expression. All have partners on the tammar X, along with homologs on the human X. Nonsynonymous and synonymous substitution ratios for nine of the tammar XY gene pairs indicate that they are each under purifying selection. All 10 were also identified as being on the Y in Tasmanian devil (Sarcophilus harrisii; a distantly related Australian marsupial); however, seven have been lost from the human Y. Maximum likelihood phylogenetic analyses of the wallaby YX genes, with respective homologs from other vertebrate representatives, revealed that three marsupial Y genes (HCFC1X/Y, MECP2X/Y, and HUWE1X/Y) were members of the ancestral therian pseudoautosomal region (PAR) at the time of the marsupial/eutherian split; three XY pairs (SOX3/SRY, RBMX/Y, and ATRX/Y) were isolated from each other before the marsupial/eutherian split, and the remaining three (RPL10X/Y, PHF6X/Y, and UBA1/UBE1Y) have a more complex evolutionary history. Thus, the small marsupial Y chromosome is surprisingly rich in ancient genes that are retained in at least Australian marsupials and evolved from testis-brain expressed genes on the X. PMID:22128133

  18. Evolutionary history of novel genes on the tammar wallaby Y chromosome: Implications for sex chromosome evolution

    Science.gov (United States)

    Murtagh, Veronica J.; O'Meally, Denis; Sankovic, Natasha; Delbridge, Margaret L.; Kuroki, Yoko; Boore, Jeffrey L.; Toyoda, Atsushi; Jordan, Kristen S.; Pask, Andrew J.; Renfree, Marilyn B.; Fujiyama, Asao; Graves, Jennifer A. Marshall; Waters, Paul D.

    2012-01-01

    We report here the isolation and sequencing of 10 Y-specific tammar wallaby (Macropus eugenii) BAC clones, revealing five hitherto undescribed tammar wallaby Y genes (in addition to the five genes already described) and several pseudogenes. Some genes on the wallaby Y display testis-specific expression, but most have low widespread expression. All have partners on the tammar X, along with homologs on the human X. Nonsynonymous and synonymous substitution ratios for nine of the tammar XY gene pairs indicate that they are each under purifying selection. All 10 were also identified as being on the Y in Tasmanian devil (Sarcophilus harrisii; a distantly related Australian marsupial); however, seven have been lost from the human Y. Maximum likelihood phylogenetic analyses of the wallaby YX genes, with respective homologs from other vertebrate representatives, revealed that three marsupial Y genes (HCFC1X/Y, MECP2X/Y, and HUWE1X/Y) were members of the ancestral therian pseudoautosomal region (PAR) at the time of the marsupial/eutherian split; three XY pairs (SOX3/SRY, RBMX/Y, and ATRX/Y) were isolated from each other before the marsupial/eutherian split, and the remaining three (RPL10X/Y, PHF6X/Y, and UBA1/UBE1Y) have a more complex evolutionary history. Thus, the small marsupial Y chromosome is surprisingly rich in ancient genes that are retained in at least Australian marsupials and evolved from testis–brain expressed genes on the X. PMID:22128133

  19. Sexual dimorphism in white campion: complex control of carpel number is revealed by Y chromosome deletions

    International Nuclear Information System (INIS)

    Sexual dimorphism in the dioecious plant white campion (Silene latifolia = Melandrium album) is under the control of two main regions on the Y chromosome. One such region, encoding the gynoecium-suppressing function (GSF), is responsible for the arrest of carpel initiation in male flowers. To generate chromosomal deletions, we used pollen irradiation in male plants to produce hermaphroditic mutants (bsx mutants) in which carpel development was restored. The mutants resulted from alterations in at least two GSF chromosomal regions, one autosomal and one located on the distal half of the (p)-arm of the Y chromosome. The two mutations affected carpel development independently, each mutation showing incomplete penetrance and variegation, albeit at significantly different levels. During successive meiotic generations, a progressive increase in penetrance and a reduction in variegation levels were observed and quantified at the level of the Y-linked GSF (GSF-Y). Possible mechanisms are proposed to explain the behavior of the bsx mutations: epigenetic regulation or/and second-site mutation of modifier genes. In addition, studies on the inheritance of the hermaphroditic trait showed that, unlike wild-type Y chromosomes, deleted Y chromosomes can be transmitted through both the male and the female lines. Altogether, these findings bring experimental support, on the one hand, to the existence on the Y chromosome of genic meiotic drive function(s) and, on the other hand, to models that consider that dioecy evolved through multiple mutation events. As such, the GSF is actually a system containing more than one locus and whose primary component is located on the Y chromosome

  20. Novel gene acquisition on carnivore Y chromosomes.

    Directory of Open Access Journals (Sweden)

    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.

  1. Chromosome differentiation patterns during cichlid fish evolution

    Directory of Open Access Journals (Sweden)

    Nirchio Mauro

    2010-06-01

    Full Text Available Abstract Background Cichlid fishes have been the subject of increasing scientific interest because of their rapid adaptive radiation which has led to an extensive ecological diversity and their enormous importance to tropical and subtropical aquaculture. To increase our understanding of chromosome evolution among cichlid species, karyotypes of one Asian, 22 African, and 30 South American cichlid species were investigated, and chromosomal data of the family was reviewed. Results Although there is extensive variation in the karyotypes of cichlid fishes (from 2n = 32 to 2n = 60 chromosomes, the modal chromosome number for South American species was 2n = 48 and the modal number for the African ones was 2n = 44. The only Asian species analyzed, Etroplus maculatus, was observed to have 46 chromosomes. The presence of one or two macro B chromosomes was detected in two African species. The cytogenetic mapping of 18S ribosomal RNA (18S rRNA gene revealed a variable number of clusters among species varying from two to six. Conclusions The karyotype diversification of cichlids seems to have occurred through several chromosomal rearrangements involving fissions, fusions and inversions. It was possible to identify karyotype markers for the subfamilies Pseudocrenilabrinae (African and Cichlinae (American. The karyotype analyses did not clarify the phylogenetic relationship among the Cichlinae tribes. On the other hand, the two major groups of Pseudocrenilabrinae (tilapiine and haplochromine were clearly discriminated based on the characteristics of their karyotypes. The cytogenetic mapping of 18S ribosomal RNA (18S rRNA gene did not follow the chromosome diversification in the family. The dynamic evolution of the repeated units of rRNA genes generates patterns of chromosomal distribution that do not help follows the phylogenetic relationships among taxa. The presence of B chromosomes in cichlids is of particular interest because they may not be represented in

  2. Different regions of the immunoglobulin heavy-chain locus are involved in chromosomal translocations in distinct pathogenic forms of Burkitt lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Neri, A.; Barriga, F.; Knowles, D.M.; Magrath, I.T.; Dalla-Favera, R.

    1988-04-01

    The authors show that endemic (eBL), sporadic (sBL), and acquired immunodeficiency syndrome-associated (AIDS-BL) forms of Burkitt lymphoma (BL) carrying t(8; 14) chromosomal translocations display different breakpoints within the immunoglobulin heavy-chain locus (IGH) on chromosome 14. In sBL (7 out of 11) and AIDS-BL (5 out of 6), the breakpoints occurred within or near the IGH ..mu.. switch (S/sub mu/) region on chromosome 14 and within the c-myc locus (MYC) on chromosome 8. In most eBL (13 out of 16) the breakpoints were mapped within or 5' to the IGH joining J/sub H/ region on chromosome 14 and outside the MYC locus on chromosome 8. Cloning and sequencing of the (8; 14) chromosomal junctions from two eBL cell lines and one eBL biopsy sample show that the recombination do not involve IGH-specific recombination signals on chromosome 14 or homologous sequences on chromosome 8, suggesting that these events are not likely to be mediated by the same mechanisms or enzymes as in IGH rearrangements. In general, these data have implications for the timing of occurrence of chromosomal translocations during B-cell differentiation in different BL types.

  3. 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

  4. 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.

  5. "Mitochondrial Eve", "Y Chromosome Adam", testosterone, and human evolution.

    Science.gov (United States)

    Howard, James Michael

    2002-01-01

    I suggest primate evolution began as a consequence of increased testosterone in males which increased aggression and sexuality, therefore, reproduction and success. With time, negative effects of excessive testosterone reduced spermatogenesis and started a decline of the group. Approximately 30-40 million years ago, the gene DAZ (Deleted in AZoospermia) appeared on the Y chromosome, increased spermatogenesis, and rescued the early primates from extinction. (Note: DAZ is considered by some to specifically, positively affect spermatogenesis; others suggest it has no effect on spermatogenesis.) Hominid evolution continued with increasing testosterone. The advent of increased testosterone in females of Homo erectus (or Homo ergaster) increased the female-to-male body size ratio, and eventually produced another era of excessive testosterone. Excessive testosterone caused a reduction in population size (bottleneck) that produced the "Mitochondrial Eve" (ME) mechanism. (Only certain females continued during the bottleneck to transmit their mitochondrial DNA.) That is, the ME mechanism culminated, again, in excessive testosterone and reduced spermatogenesis in the hominid line. Approximately 50,000 to 200,000 years ago, a "doubling" of the DAZ gene occurred on the Y chromosome in hominid males which rescued the hominid line with increased spermatogenesis in certain males. This produced the "Y Chromosome Adam" event. The doubling of DAZ allowed further increases in testosterone in hominids that resulted in the increased size and development of the brain. Modern humans periodically fluctuate between the positive and negative consequences of increased levels of testosterone, currently identifiable as the secular trend, increased infections, and reduced spermatogenesis. PMID:12449688

  6. High Line

    OpenAIRE

    Jagielska, Anna

    2015-01-01

    This project examines The High Line in New York City and what is due to its success. The park, which runs through the meatpacking district in Manhattan, is on an old rail line that was abandoned from the 1980s. Two private locals, Joshua and Hammond, founded the non-profit organization “Friends of The High Line” and established the rail line into a public park. The aesthetics of the park is the wildness of the nature and the modern architecture in the middle of Manhattan mixed with a sustaina...

  7. 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...

  8. Information Technology and Transportation: Substitutes or Complements?

    OpenAIRE

    Oliver, Atara Stephanie

    2013-01-01

    The increased availability and prevalence of Information and Communications Technology (ICT) provides opportunities to use such products as substitutes for transportation. Common examples of this substitution are telecommuting, video conferences, and online classes. However, despite the intuitive appeal of a substitution relationship existing between ICT and transportation, prior research has indicated that the relationship between ICT and transportation is quite complex; at times ICT substit...

  9. 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.

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

    OpenAIRE

    Yerle Martine; Ducos Alain; Pinton Alain

    2003-01-01

    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...

  11. Sex chromosome evolution: platypus gene mapping suggests that part of the human X chromosome was originally autosomal.

    OpenAIRE

    Watson, J M; Spencer, J. A.; Riggs, A D; Graves, J.A.

    1991-01-01

    To investigate the evolution of the mammalian sex chromosomes, we have compared the gene content of the X chromosomes in the mammalian groups most distantly related to man (marsupials and monotremes). Previous work established that genes on the long arm of the human X chromosome are conserved on the X chromosomes in all mammals, revealing that this region was part of an ancient mammalian X chromosome. However, we now report that several genes located on the short arm of the human X chromosome...

  12. Chromosomal mutations induced by triplex-forming oligonucleotides in mammalian cells.

    OpenAIRE

    Vasquez, K M; Wang, G; Havre, P A; Glazer, P M

    1999-01-01

    Specific recognition of a region of duplex DNA by triplex-forming oligonucleotides (TFOs) provides an attractive strategy for genetic manipulation. Based on this, we have investigated the ability of the triplex-directed approach to induce mutations at a chromosomal locus in living cells. A mouse fibroblast cell line was constructed containing multiple chromosomal copies of the lambdasupFG1 vector carrying the supFG1 mutation-reporter gene. Cells were treated with specific (psoAG30) or control...

  13. Chromosome 3p microsatellite allelotyping in neuroblastoma: a report on the technical hurdles.

    Science.gov (United States)

    Hoebeeck, Jasmien; De Wilde, Bram; Michels, Evi; Combaret, Valérie; Yigit, Nurten; De Smet, Els; Van Roy, Nadine; Stanbridge, Eric; Ru, Ning; Laureys, Geneviève; De Paepe, Anne; Speleman, Frank; Vandesompele, Jo

    2009-10-01

    Pinpointing critical regions of recurrent loss may help localize tumor suppressor genes. To determine the regions of loss on chromosome 3p in neuroblastoma, we performed loss of heterozygosity analysis using 16 microsatellite markers in a series of 65 primary tumors and 29 neuroblastoma cell lines. In this study, we report the results and discuss the technical hurdles that we encountered during data generation and interpretation that are of relevance for current studies or tests employing microsatellites. To provide functional support for the implication of 3p tumor suppressor genes in this childhood malignancy, we performed a microcell-mediated chromosome 3 transfer in neuroblastoma cells. PMID:19544108

  14. Development of an integrated computerized scheme for metaphase chromosome image analysis: a robustness experiment

    Science.gov (United States)

    Wang, Xingwei; Zheng, Bin; Li, Shibo; Mulvihill, John J.; Wood, Marc C.; Yuan, Chaowei; Chen, Wei; Liu, Hong

    2008-02-01

    Our integrated computer-aided detection (CAD) scheme includes three basic modules. The first module detects whether a microscopic digital image depicts a metaphase chromosome cell. If a cell is detected, the scheme will justify whether it is analyzable with a decision tree. Once an analyzable cell is detected, the second module is applied to segment individual chromosomes and to compute two important features. Specifically, the scheme utilizes a modified thinning algorithm to identify the medial axis of a chromosome. By tracking perpendicular lines along the medial axis, the scheme computes four feature profiles, identifies centromeres, and assigns polarities of chromosomes based on a set of pre-optimized rules. The third module is followed to classify chromosomes into 24 types. In this module, each chromosome is initially represented by a vector of 31 features. A two-layer classifier with 8 artificial neural networks (ANN) is optimized by a genetic algorithm. A testing chromosome is first classified into one of the seven groups by the ANN in the first layer. Another ANN is then automatically selected from the seven ANNs in the second layer (one for each group) to further classify this chromosome into one of 24 types. To test the performance and robustness of this CAD scheme, we randomly selected and assembled an independent testing dataset. The dataset contains 100 microscopic digital images including 50 analyzable and 50 un-analyzable metphase cells identified by the experts. The centromere location, the corresponding polarity, and karyotype for each individual chromosome were recorded in the "truth" file. The performance of the CAD scheme applied to this image dataset is analyzed and compared with the results in the true file. The assessment accuracies are 93% for the first module, 90.8% for centromere identification and 93.2% for polarity assignment in the second module, over 96% for six chromosome groups and 81.8% for one group in the third module

  15. Blurring lines

    OpenAIRE

    Howard, Heidi C; Knoppers, Bartha Maria; Borry, Pascal

    2010-01-01

    Companies that offer direct-to-consumer genetic testing and conduct research are blurring the line between customers and research subjects. Should these companies adhere to the same ethical regulations as academic researchers?

  16. High Line

    DEFF Research Database (Denmark)

    Kiib, Hans

    2015-01-01

    . 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......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...... 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, and...

  17. Mechanism of the t(14;18) chromosomal translocation: structural analysis of both derivative 14 and 18 reciprocal partners

    International Nuclear Information System (INIS)

    To elucidate the mechanism of the t(14;18)(q32;q21) chromosomal translocation found in follicular lymphoma, the authors examined the structure of both derivative (der) chromosomal breakpoints as well as their germ-line predecessors. They noted that chromosome segment 18q21 was juxtaposed with immunoglobulin heavy (H) chain gene diversity (D/sub H/) regions on all five der(18) chromosomes they examined, and they confirmed the juncture with immunoglobulin H-chain gene joining (J/sub H/) regions on the der(14) chromosome. However, the t(14;18) was not fully reciprocal in that chromosome 14 DNA between the D/sub H/ and J/sub H/ regions was deleted. Furthermore, extra nucleotides, reminiscent of N segments, were present at the der(14) and possibly der(18) junctions. This indicates that despite the mature B-cell phenotype of follicular lymphoma, the t(14;18) occurs during attempted D/sub H/-J/sub H/ joining, the earliest event in immunoglobulin rearrangement in a pre-B-cell. The detailed analysis of the germ-line 18q21 region indicated that most breakpoints clustered within a 150-base-pair major breakpoint region. A direct repeat duplication of chromosome 18 sequences was discovered at both chromosomal junctures, typical of the repair of a naturally occurring staggered double-stranded DNA break. These results prompt a translocation model with illegitimate pairing of a staggered double-stranded DNA break at 18q21 and an immunoglobulin endonuclease-mediated break at 14q32 and with N-segment addition, repair, and ligation to generate der(14) and der(18) chromosomes

  18. Mechanism of the t(14; 18) chromosomal translocation: structural analysis of both derivative 14 and 18 reciprocal partners

    Energy Technology Data Exchange (ETDEWEB)

    Bakhshi, A.; Wright, J.J.; Graninger, W.; Seto, M.; Owens, J.; Cossman, J.; Jensen, J.P.; Goldman, P.; Korsmeyer, S.J.

    1987-04-01

    To elucidate the mechanism of the t(14;18)(q32;q21) chromosomal translocation found in follicular lymphoma, the authors examined the structure of both derivative (der) chromosomal breakpoints as well as their germ-line predecessors. They noted that chromosome segment 18q21 was juxtaposed with immunoglobulin heavy (H) chain gene diversity (D/sub H/) regions on all five der(18) chromosomes they examined, and they confirmed the juncture with immunoglobulin H-chain gene joining (J/sub H/) regions on the der(14) chromosome. However, the t(14;18) was not fully reciprocal in that chromosome 14 DNA between the D/sub H/ and J/sub H/ regions was deleted. Furthermore, extra nucleotides, reminiscent of N segments, were present at the der(14) and possibly der(18) junctions. This indicates that despite the mature B-cell phenotype of follicular lymphoma, the t(14;18) occurs during attempted D/sub H/-J/sub H/ joining, the earliest event in immunoglobulin rearrangement in a pre-B-cell. The detailed analysis of the germ-line 18q21 region indicated that most breakpoints clustered within a 150-base-pair major breakpoint region. A direct repeat duplication of chromosome 18 sequences was discovered at both chromosomal junctures, typical of the repair of a naturally occurring staggered double-stranded DNA break. These results prompt a translocation model with illegitimate pairing of a staggered double-stranded DNA break at 18q21 and an immunoglobulin endonuclease-mediated break at 14q32 and with N-segment addition, repair, and ligation to generate der(14) and der(18) chromosomes.

  19. Interplay between type 1A topoisomerases and gyrase in chromosome segregation in Escherichia coli.

    Science.gov (United States)

    Usongo, Valentine; Tanguay, Cynthia; Nolent, Flora; Bessong, Jill Egbe; Drolet, Marc

    2013-04-01

    Escherichia coli possesses two type 1A topoisomerases, Topo I (topA) and Topo III (topB). Topo I relaxes excess negative supercoiling, and topA mutants can grow only in the presence of compensatory mechanisms, such as gyrase mutations. topB mutants grow as well as wild-type cells. In vitro, Topo III, but not Topo I, can efficiently decatenate DNA during replication. However, in vivo, a chromosome segregation defect is seen only when both type 1A topoisomerases are absent. Here we present experimental evidence for an interplay between gyrase and type 1A topoisomerases in chromosome segregation. We found that both the growth defect and the Par(-) phenotypes of a gyrB(Ts) mutant at nonpermissive temperatures were significantly corrected by deleting topA, but only when topB was present. Overproducing Topo IV, the major cellular decatenase, could not substitute for topB. We also show that overproducing Topo III at a very high level could suppress the Par(-) phenotype. We previously found that the growth and chromosome segregation defects of a triple topA rnhA gyrB(Ts) mutant in which gyrase supercoiling activity was strongly inhibited could be corrected by overproducing Topo III (V. Usongo, F. Nolent, P. Sanscartier, C. Tanguay, S. Broccoli, I. Baaklini, K. Drlica, and M. Drolet, Mol. Microbiol. 69:968-981, 2008). We show here that this overproduction could be bypassed by substituting the gyrB(Ts) allele for a gyrB(+) one or by growing cells in a minimal medium, conditions that reduced both topA- and rnhA-dependent unregulated replication. Altogether, our data point to a role for Topo III in chromosome segregation when gyrase is inefficient and suggest that Topo I plays an indirect role via supercoiling regulation. PMID:23396913

  20. A residue substitution in the plastid ribosomal protein L12/AL1 produces defective plastid ribosome and causes early seedling lethality in rice.

    Science.gov (United States)

    Zhao, Dong-Sheng; Zhang, Chang-Quan; Li, Qian-Feng; Yang, Qing-Qing; Gu, Ming-Hong; Liu, Qiao-Quan

    2016-05-01

    The plastid ribosome is essential for chloroplast biogenesis as well as seedling formation. As the plastid ribosome closely resembles the prokaryotic 70S ribosome, many plastid ribosomal proteins (PRPs) have been identified in higher plants. However, their assembly in the chloroplast ribosome in rice remains unclear. In the present study, we identified a novel rice mutant, albino lethal 1 (al1), from a chromosome segment substitution line population. The al1 mutant displayed an albino phenotype at the seedling stage and did not survive past the three-leaf stage. No other apparent differences in plant morphology were observed in the al1 mutant. The albino phenotype of the al1 mutant was associated with decreased chlorophyll content and abnormal chloroplast morphology. Using fine mapping, AL1 was shown to encode the PRPL12, a protein localized in the chloroplasts of rice, and a spontaneous single-nucleotide mutation (C/T), resulting in a residue substitution from leucine in AL1 to phenylalanine in al1, was found to be responsible for the early seedling lethality. This point mutation is located at the L10 interface feature of the L12/AL1 protein. Yeast two-hybrid analysis showed that there was no physical interaction between al1 and PRPL10. In addition, the mutation had little effect on the transcript abundance of al1, but had a remarkable effect on the protein abundance of al1 and transcript abundance of chloroplast biogenesis-related and photosynthesis-related genes. These results provide a first glimpse into the molecular details of L12's function in rice. PMID:26873698

  1. Nonrandom chromosomal changes in human malignant cells

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, J D

    1977-01-01

    The role of chromosomal changes in human malignant cells has been the subject of much debate. The observation of nonrandom chromosomal changes has become well recognized in chronic myelogenous leukemia, and more recently in acute myelogenous leukemia. In the present report, data are presented on the sites of duplication of chromosome No. 1 in hematologic disorders. Trisomy for region lq25 to lq32 was observed in every one of 34 patients whose cells showed duplication of some part of chromosome No. 1. Adjacent regions lq21 to lq25, and lq32 to lqter, also were trisomic in the majority of patients. Two patients had deletions, one of lq32 to qter, and the other, of lp32 to pter. The sites of chromosomal breaks leading to trisomy differ from those involved in balanced reciprocal translocations. Some of these sites are sometimes, but not always, vulnerable in constitutional chromosomal abnormalities. The nature of the proliferative advantage conferred on myeloid cells by these chromosomal changes is unknown.

  2. Chromosome number evolution in skippers (Lepidoptera, Hesperiidae).

    Science.gov (United States)

    Lukhtanov, Vladimir A

    2014-01-01

    Lepidoptera (butterflies and moths), as many other groups of animals and plants, simultaneously represent preservation of ancestral karyotype in the majority of families with a high degree of chromosome number instability in numerous independently evolved phylogenetic lineages. However, the pattern and trends of karyotype evolution in some Lepidoptera families are poorly studied. Here I provide a survey of chromosome numbers in skippers (family Hesperiidae) based on intensive search and analysis of published data. I demonstrate that the majority of skippers preserve the haploid chromosome number n=31 that seems to be an ancestral number for the Hesperiidae and the order Lepidoptera at whole. However, in the tribe Baorini the derived number n=16 is the most typical state which can be used as a (syn)apomorphic character in further phylogenetic investigations. Several groups of skippers display extreme chromosome number variations on within-species (e.g. the representatives of the genus Carcharodus Hübner, [1819]) and between-species (e.g. the genus Agathymus Freeman, 1959) levels. Thus, these groups can be used as model systems for future analysis of the phenomenon of chromosome instability. Interspecific chromosomal differences are also shown to be useful for discovering and describing new cryptic species of Hesperiidae representing in such a way a powerful tool in biodiversity research. Generally, the skipper butterflies promise to be an exciting group that will significantly contribute to the growing knowledge of patterns and processes of chromosome evolution. PMID:25610542

  3. Chromosome number evolution in skippers (Lepidoptera, Hesperiidae

    Directory of Open Access Journals (Sweden)

    Vladimir Lukhtanov

    2014-11-01

    Full Text Available Lepidoptera (butterflies and moths, as many other groups of animals and plants, simultaneously represent preservation of ancestral karyotype in the majority of families with a high degree of chromosome number instability in numerous independently evolved phylogenetic lineages. However, the pattern and trends of karyotype evolution in some Lepidoptera families are poorly studied. Here I provide a survey of chromosome numbers in skippers (family Hesperiidae based on intensive search and analysis of published data. I demonstrate that the majority of skippers preserve the haploid chromosome number n=31 that seems to be an ancestral number for the Hesperiidae and the order Lepidoptera at whole. However, in the tribe Baorini the derived number n=16 is the most typical state which can be used as a (synapomorphic character in further phylogenetic investigations. Several groups of skippers display extreme chromosome number variations on within-species (e.g. the representatives of the genus Carcharodus Hübner, [1819] and between-species (e.g. the genus Agathymus Freeman, 1959 levels. Thus, these groups can be used as model systems for future analysis of the phenomenon of chromosome instability. Interspecific chromosomal differences are also shown to be useful for discovering and describing new cryptic species of Hesperiidae representing in such a way a powerful tool in biodiversity research. Generally, the skipper butterflies promise to be an exciting group that will significantly contribute to the growing knowledge of patterns and processes of chromosome evolution.

  4. 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.

  5. Substitution dynamical systems spectral analysis

    CERN Document Server

    Queffélec, Martine

    2010-01-01

    This volume mainly deals with the dynamics of finitely valued sequences, and more specifically, of sequences generated by substitutions and automata. Those sequences demonstrate fairly simple combinatorical and arithmetical properties and naturally appear in various domains. As the title suggests, the aim of the initial version of this book was the spectral study of the associated dynamical systems: the first chapters consisted in a detailed introduction to the mathematical notions involved, and the description of the spectral invariants followed in the closing chapters. This approach, combined with new material added to the new edition, results in a nearly self-contained book on the subject. New tools - which have also proven helpful in other contexts - had to be developed for this study. Moreover, its findings can be concretely applied, the method providing an algorithm to exhibit the spectral measures and the spectral multiplicity, as is demonstrated in several examples. Beyond this advanced analysis, many...

  6. Group 3 chromosome bin maps of wheat and their relationship to rice chromosome 1.

    Science.gov (United States)

    Munkvold, J D; Greene, R A; Bermudez-Kandianis, C E; La Rota, C M; Edwards, H; Sorrells, S F; Dake, T; Benscher, D; Kantety, R; Linkiewicz, A M; Dubcovsky, J; Akhunov, E D; Dvorák, J; Miftahudin; Gustafson, J P; Pathan, M S; Nguyen, H T; Matthews, D E; Chao, S; Lazo, G R; Hummel, D D; Anderson, O D; Anderson, J A; Gonzalez-Hernandez, J L; Peng, J H; Lapitan, N; Qi, L L; Echalier, B; Gill, B S; Hossain, K G; Kalavacharla, V; Kianian, S F; Sandhu, D; Erayman, M; Gill, K S; McGuire, P E; Qualset, C O; Sorrells, M E

    2004-10-01

    The focus of this study was to analyze the content, distribution, and comparative genome relationships of 996 chromosome bin-mapped expressed sequence tags (ESTs) accounting for 2266 restriction fragments (loci) on the homoeologous group 3 chromosomes of hexaploid wheat (Triticum aestivum L.). Of these loci, 634, 884, and 748 were mapped on chromosomes 3A, 3B, and 3D, respectively. The individual chromosome bin maps revealed bins with a high density of mapped ESTs in the distal region and bins of low density in the proximal region of the chromosome arms, with the exception of 3DS and 3DL. These distributions were more localized on the higher-resolution group 3 consensus map with intermediate regions of high-mapped-EST density on both chromosome arms. Gene ontology (GO) classification of mapped ESTs was not significantly different for homoeologous group 3 chromosomes compared to the other groups. A combined analysis of the individual bin maps using 537 of the mapped ESTs revealed rearrangements between the group 3 chromosomes. Approximately 232 (44%) of the consensus mapped ESTs matched sequences on rice chromosome 1 and revealed large- and small-scale differences in gene order. Of the group 3 mapped EST unigenes approximately 21 and 32% matched the Arabidopsis coding regions and proteins, respectively, but no chromosome-level gene order conservation was detected. PMID:15514041

  7. Synthesis and in Vitro Cytotoxic Activity Evaluation of (E-16-(Substituted Benzylidene Derivatives of Dehydroepiandrosterone

    Directory of Open Access Journals (Sweden)

    Mohsen Vosooghi

    2013-05-01

    Full Text Available Background and the purpose of the study:Modified androsterone derivatives are class of steroidal compounds with potential anticancer properties. Various steroidal derivatives containing substitution at position 16 have shown diversified pharmacological activities. In the present study, a new series of cytotoxic 16-(substituted benzylidene derivatives of dehydroepiandrosterone (DHEA were synthesized and evaluated against three different cancer cell lines.Methods:The cytotoxic 16-(substituted benzylidene derivatives of DHEA were synthesized via aldol condensation of DHEA with corresponding benzaldehyde derivatives. The cytotoxic activity of synthesized derivatives was evaluated against three different cancer cells including KB, T47D and SK-N-MC cell lines by MTT reduction colorimetric assay.Results:The results indicated that 16-(substituted benzylidene derivatives of DHEA could be served as a potent anti-cancer agent. The 3-cholro benzylidene derivatives of DHEA was the most potent synthesized derivative especially against KB and T47D cell lines (IC50 values were 0.6 and 1.7 μM; respectively.Conclusion:The cytotoxic potential of novel benzylidene derivatives of DHEA is mainly attributed to the position and nature of the substituted group on the benzylidene pendant

  8. Chromosome heteromorphism quantified by high-resolution bivariate flow karyotyping.

    Science.gov (United States)

    Trask, B; van den Engh, G; Mayall, B; Gray, J W

    1989-11-01

    Maternal and paternal homologues of many chromosome types can be differentiated on the basis of their peak position in Hoechst 33258 versus chromomycin A3 bivariate flow karyotypes. We demonstrate here the magnitude of DNA content differences among normal chromosomes of the same type. Significant peak-position differences between homologues were observed for an average of four chromosome types in each of the karyotypes of 98 different individuals. The frequency of individuals with differences in homologue peak positions varied among chromosome types: e.g., chromosome 15, 61%; chromosome 3, 4%. Flow karyotypes of 33 unrelated individuals were compared to determine the range of peak position among normal chromosomes. Chromosomes Y, 21, 22, 15, 16, 13, 14, and 19 were most heteromorphic, and chromosomes 2-8 and X were least heteromorphic. The largest chromosome 21 was 45% larger than the smallest 21 chromosome observed. The base composition of the variable regions differed among chromosome types. DNA contents of chromosome variants determined from flow karyotypes were closely correlated to measurements of DNA content made of gallocyanin chrome alum-stained metaphase chromosomes on slides. Fluorescence in situ hybridization with chromosome-specific repetitive sequences indicated that variability in their copy number is partly responsible for peak-position variability in some chromosomes. Heteromorphic chromosomes are identified for which parental flow karyotype information will be essential if de novo rearrangements resulting in small DNA content changes are to be detected with flow karyotyping. PMID:2479266

  9. Adaptation through chromosomal inversions in Anopheles

    Directory of Open Access Journals (Sweden)

    Diego eAyala

    2014-05-01

    Full Text Available Chromosomal inversions have been repeatedly involved in local adaptation in a large number of animals and plants. The ecological and behavioral plasticity of Anopheles species - human malaria vectors - is mirrored by high amounts of polymorphic inversions. The adaptive significance of chromosomal inversions has been consistently attested by strong and significant correlations between their frequencies and a number of phenotypic traits. Here, we provide an extensive literature review of the different adaptive traits associated with chromosomal inversions in the genus Anopheles. Traits having important consequences for the success of present and future vector control measures, such as insecticide resistance and behavioral changes, are discussed.

  10. Chromosomal abnormalities in patients with sperm disorders

    Directory of Open Access Journals (Sweden)

    L. Y. Pylyp

    2013-02-01

    Full Text Available Chromosomal abnormalities are among the most common genetic causes of spermatogenic disruptions. Carriers of chromosomal abnormalities are at increased risk of infertility, miscarriage or birth of a child with unbalanced karyotype due to the production of unbalanced gametes. The natural selection against chromosomally abnormal sperm usually prevents fertilization with sperm barring in cases of serious chromosomal abnormalities. However, assisted reproductive technologies in general and intracytoplasmic sperm injection in particular, enable the transmission of chromosomal abnormalities to the progeny. Therefore, cytogenetic studies are important in patients with male factor infertility before assisted reproduction treatment. The purpose of the current study was to investigate the types and frequencies of chromosomal abnormalities in 724 patients with infertility and to estimate the risk of chromosomal abnormalities detection in subgroups of patients depending on the severity of spermatogenic disruption, aiming at identifying groups of patients in need of cytogenetic studies. Karyotype analysis was performed in 724 blood samples of men attending infertility clinic. Chromosomal preparation was performed by standard techniques. At least 20 GTG-banded metaphase plates with the resolution from 450 to 750 bands per haploid set were analysed in each case. When chromosomal mosaicism was suspected, this number was increased to 50. Abnormal karyotypes were observed in 48 (6.6% patients, including 67% of autosomal abnormalities and 33% of gonosomal abnormalities. Autosomal abnormalities were represented by structural rearrangements. Reciprocal translocations were the most common type of structural chromosomal abnormalities in the studied group, detected with the frequency of 2.6% (n = 19, followed by Robertsonian translocation, observed with the frequency of 1.2% (n = 9. The frequency of inversions was 0.6% (n = 4. Gonosomal abnormalities included 14 cases

  11. Recombinant protein expression by targeting pre-selected chromosomal loci

    Directory of Open Access Journals (Sweden)

    Krömer Wolfgang

    2009-12-01

    Full Text Available Abstract Background Recombinant protein expression in mammalian cells is mostly achieved by stable integration of transgenes into the chromosomal DNA of established cell lines. The chromosomal surroundings have strong influences on the expression of transgenes. The exploitation of defined loci by targeting expression constructs with different regulatory elements is an approach to design high level expression systems. Further, this allows to evaluate the impact of chromosomal surroundings on distinct vector constructs. Results We explored antibody expression upon targeting diverse expression constructs into previously tagged loci in CHO-K1 and HEK293 cells that exhibit high reporter gene expression. These loci were selected by random transfer of reporter cassettes and subsequent screening. Both, retroviral infection and plasmid transfection with eGFP or antibody expression cassettes were employed for tagging. The tagged cell clones were screened for expression and single copy integration. Cell clones producing > 20 pg/cell in 24 hours could be identified. Selected integration sites that had been flanked with heterologous recombinase target sites (FRTs were targeted by Flp recombinase mediated cassette exchange (RMCE. The results give proof of principle for consistent protein expression upon RMCE. Upon targeting antibody expression cassettes 90-100% of all resulting cell clones showed correct integration. Antibody production was found to be highly consistent within the individual cell clones as expected from their isogenic nature. However, the nature and orientation of expression control elements revealed to be critical. The impact of different promoters was examined with the tag-and-targeting approach. For each of the chosen promoters high expression sites were identified. However, each site supported the chosen promoters to a different extent, indicating that the strength of a particular promoter is dominantly defined by its chromosomal context

  12. Chromosome damage evolution after low and high LET irradiation

    Science.gov (United States)

    Andreev, Sergey; Eidelman, Yuri

    Ionizing radiation induces DNA and chromatin lesions which are converted to chromosome lesions detected in the first post-irradiation mitosis by classic cytogenetic techniques as chromosomal aberrations (CAs). These techniques allow to monitor also delayed aberrations observed after many cell generations post-irradiation - the manifestation of chromosomal instability phenotype (CIN). The problem discussed is how to predict time evolution from initial to delayed DNA/chromosome damage. To address this question, in the present work a mechanistic model of CIN is elaborated which integrates pathways of (*) DNA damage induction and its conversion to chromosome lesions (aberrations), (**) lesion transmission and generation through cell cycles. Delayed aberrations in subsequent cycles are formed in the model owing to two pathways, DNA damage generation de novo as well as CA transmission from previous cycles. DNA damage generation rate is assumed to consist of bystander and non-bystander components. Bystander signals impact all cells roughly equally, whereas non-bystander DSB generation rate differs for the descendants of unirradiated and irradiated cells. Monte Carlo simulation of processes underlying CIN allows to predict the time evolution of initial radiation-induced damage - kinetics curve for delayed unstable aberrations (dicentrics) together with dose response and RBE as a function of time after high vs low LET irradiation. The experimental data for radiation-induced CIN in TK6 lymphoblastoid cells and human lymphocytes irradiated with low (gamma) and high (Fe, C) LET radiation are analyzed on the basis of the proposed model. One of the conclusions is that without bystander signaling, just taking into account the initial DNA damage and non-bystander DSB generation, it is impossible to describe the available experimental data for high-LET-induced CIN. The exact contribution of bystander effects for high vs low LET remains unknown, but the relative contribution may be

  13. Trisomy 8: a common finding in mouse embryonic stem (ES cell lines

    Directory of Open Access Journals (Sweden)

    Kim Young Mi

    2013-01-01

    Full Text Available Abstract Background Obtaining a germ cell line is one of the most important steps in developing a transgenic or knockout mouse with a targeted mutated gene of interest. A common problem with this technology is that embryonic stem (ES cells often lack, or are extremely inefficient at, germ line transmission. Results To determine whether chromosomal anomalies are correlated with inefficient ES cell germ line transmission, we examined 97 constructed ES cell lines using conventional cytogenetic analysis, and fluorescence in situ hybridization (FISH. Chromosomal abnormalities occurred in 44 (45% out of the 97 specimens analyzed: 31 specimens had trisomy 8 or mosaic trisomy 8, eight specimens had partial trisomy 8 resulting from unbalanced translocations, and five specimens had other chromosomal anomalies. Conclusions Our data suggest that chromosomal analysis is an important tool for improving the yield and quality of gene targeting experiments.

  14. 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...

  15. 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).

  16. A virtual substitution of Brouwer choice sequence

    CERN Document Server

    Lange, Klaus

    2009-01-01

    Step by step a substitution of the well known Brouwer choice sequence will be constructed. It begins with an establishing of quasi alternating prime number series followed by a construction of a virtual sequence in sense of the virtual set definition. The last step gives reasons for why this virtual sequence substitutes the choice sequence created by L. E. J. Brouwer.

  17. 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.

  18. 24 CFR 235.206 - Substitute mortgagors.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Substitute mortgagors. 235.206... 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...

  19. 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, v...

  20. 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...

  1. 29 CFR 500.216 - Substituted service.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Substituted service. 500.216 Section 500.216 Labor... Service § 500.216 Substituted service. (a) Pursuant to section 102(5) of the Act, the Secretary, when so designated by a court, shall accept service of summons in any action arising under the Act or...

  2. Chromosome landmarks and autosome-sex chromosome translocations in Rumex hastatulus, a plant with XX/XY1Y2 sex chromosome system.

    Science.gov (United States)

    Grabowska-Joachimiak, Aleksandra; Kula, Adam; Książczyk, Tomasz; Chojnicka, Joanna; Sliwinska, Elwira; Joachimiak, Andrzej J

    2015-06-01

    Rumex hastatulus is the North American endemic dioecious plant with heteromorphic sex chromosomes. It is differentiated into two chromosomal races: Texas (T) race characterised by a simple XX/XY sex chromosome system and North Carolina (NC) race with a polymorphic XX/XY1Y2 sex chromosome system. The gross karyotype morphology in NC race resembles the derived type, but chromosomal changes that occurred during its evolution are poorly understood. Our C-banding/DAPI and fluorescence in situ hybridization (FISH) experiments demonstrated that Y chromosomes of both races are enriched in DAPI-positive sequences and that the emergence of polymorphic sex chromosome system was accompanied by the break of ancestral Y chromosome and switch in the localization of 5S rDNA, from autosomes to sex chromosomes (X and Y2). Two contrasting domains were detected within North Carolina Y chromosomes: the older, highly heterochromatinised, inherited from the original Y chromosome and the younger, euchromatic, representing translocated autosomal material. The flow-cytometric DNA estimation showed ∼3.5 % genome downsizing in the North Carolina race. Our results are in contradiction to earlier reports on the lack of heterochromatin within Y chromosomes of this species and enable unambiguous identification of autosomes involved in the autosome-heterosome translocation, providing useful chromosome landmarks for further studies on the karyotype and sex chromosome differentiation in this species. PMID:25394583

  3. Genes for resistance to stripe rust on chromosome 2B and their application in wheat breeding

    Institute of Scientific and Technical Information of China (English)

    Peigao Luo; Xueyun Hu; Huaiyu Zhang; Zhenglong Ren

    2009-01-01

    Stripe rust,caused by Puccinia striiformis f.sp.tritici,is one of the most damaging diseases of wheat worldwide.Growing resistant cultivars is the most economic and environmental friendly way to control the disease.There are many resistance genes to stripe rust located on wheat chromosome 2B.Here,we propose a strategy to construct the recombinant wheat chromosome 2B with multiple resistances to stripe rust by making crosses between wheat lines or cultivars carrying Yr genes and using marker-assisted selection,based on the reported information about resistance spectrum,chromosomal location,and linked markers of the genes.Pyramiding the resistance genes on 2B would afford a valuable strategy to control the disease by cultivating varieties with durable resistance.The possibility,efficiency,and prospect of the suggested strategy are reviewed in the paper.

  4. Integration of hepatitis B virus DNA in chromosome-specific satellite sequences

    International Nuclear Information System (INIS)

    The authors previously reported the cloning and detailed analysis of the integrated hepatitis B virus sequences in a human hepatoma cell line. They report here the integration of at least one of hepatitis B virus at human satellite DNA sequences. The majority of the cellular sequences identified by this satellite were organized as a multimeric composition of a 0.6-kilobase EcoRI fragment. This clone hybridized in situ almost exclusively to the centromeric heterochromatin of chromosomes 1 and 16 and to a lower extent to chromosome 2 and to the heterochromatic region of the Y chromosome. The immediate flanking host sequence appeared as a hierarchy of repeating units which were almost identical to a previously reported human satellite III DNA sequence

  5. Chromosome radiosensitivity and kinetics of proliferation of peripheral lymphocytes in individuals with aneuploid karyotype

    International Nuclear Information System (INIS)

    Experimentally investigated was the radiosensitivity of chromosomes and the kinetics of the proliferation of peripheral lymphocytes in patients with aneuploid (DS and TS) and normal karyotype irradiated in vitro in the Go stage of the cell cycle. Trisomic lymphocytes were found to proliferate more rapidly in the in vitro culture and to be more sensitive than diploid cell populations. In monosomic lymphocytes in Turner syndrome patients, the proliferation and incidence of chromosomal abberations was similar to the disomic lines in Down's syndrome patients and in Turner syndrome patients, and to that found in persons with a normal karyotype. The results of the experiment show that there is a relationship between the proliferation rate of peripheral lymphocytes cultures in vitro and the radiosensivity of chromosomes. (author). 1 tab., 3 figs., 11 refs

  6. Visualization of yeast chromosomal DNA

    Science.gov (United States)

    Lubega, Seth

    1990-01-01

    The DNA molecule is the most significant life molecule since it codes the blue print for other structural and functional molecules of all living organisms. Agarose gel electrophoresis is now being widely used to separate DNA of virus, bacteria, and lower eukaryotes. The task was undertaken of reviewing the existing methods of DNA fractionation and microscopic visualization of individual chromosonal DNA molecules by gel electrophoresis as a basis for a proposed study to investigate the feasibility of separating DNA molecules in free fluids as an alternative to gel electrophoresis. Various techniques were studied. On the molecular level, agarose gel electrophoresis is being widely used to separate chromosomal DNA according to molecular weight. Carl and Olson separate and characterized the entire karyotype of a lab strain of Saccharomyces cerevisiae. Smith et al. and Schwartz and Koval independently reported the visualization of individual DNA molecules migrating through agarose gel matrix during electrophoresis. The techniques used by these researchers are being reviewed in the lab as a basis for the proposed studies.

  7. Transferring of the 2Ai-2 Chromosome into Wheat ph1b Genetic Background by Using Related Molecular Markers%利用分子标记将2Ai-2染色体转移到小麦ph1b遗传背景的研究

    Institute of Scientific and Technical Information of China (English)

    雷昊; 张悦; 林志珊; 徐琼芳; 叶兴国

    2012-01-01

    小麦ph1b突变体可诱导部分同源染色体配对和交换,产生遗传上较为稳定、补偿性较好的重组体.将外源染色体引入ph1b的小麦遗传背景是产生目标染色体重组体的基础,但ph1b植株没有明显而稳定的表型性状,难以从表型上进行选择.本研究利用CSph1b缺失区中的分子标记Mads及外源染色体特异的分子标记P4和P68,对小麦-中间偃麦草2Ai-2(2B)异代换系N420与CSph1b的杂种F2群体及其衍生的F5株系进行ph1b-2Ai-2染色体综合体的选择,高效地获得了目标基因型.%Incident of homeologous chromosome pairing and exchange often occur in hexaploid wheat with phlb genetic background which can produce compensable and genetic stable recombinants. Therefore,transferring alien chromosomes into a wheat material with phlb background is the basis of generating translocations between the target chromosomes. However, it is difficult to identify phlb genotype according to its phenotype. In present study,some target plants with phlb and the alien chromosome 2Ai-2 were selected effectively by using molecular markers Mads (on the deletion region of phlb) for phlb,P4 and P68 (on the alien chromosome) for 2Ai-2 in the F2population of CSphlb crossed with N420,a wheat-Thiaopyrum intermedium 2B(2Ai-2)substitution line,and their derivative F5lines.

  8. Tracking Chromosome Evolution in Southern African Gerbils Using Flow-Sorted Chromosome Paints

    OpenAIRE

    Knight, L.I.; Ng, B. L.; Cheng, W; Fu, B.; Yang, F.; Rambau, R V

    2013-01-01

    Desmodillus and Gerbilliscus (formerly Tatera) comprise a monophyletic group of gerbils (subfamily Gerbillinae) which last shared an ancestor approximately 8 million years ago; diploid chromosome number variation among the species ranges from 2n = 36 to 2n = 50. In an attempt to shed more light on chromosome evolution and speciation in these rodents, we compared the karyotypes of 7 species, representing 3 genera, based on homology data revealed by chromosome painting with probes derived from ...

  9. Sex Chromosome Evolution in Amniotes: Applications for Bacterial Artificial Chromosome Libraries

    OpenAIRE

    Janes, Daniel E.; Nicole Valenzuela; Tariq Ezaz; Chris Amemiya; Edwards, Scott V.

    2011-01-01

    Variability among sex chromosome pairs in amniotes denotes a dynamic history. Since amniotes diverged from a common ancestor, their sex chromosome pairs and, more broadly, sex-determining mechanisms have changed reversibly and frequently. These changes have been studied and characterized through the use of many tools and experimental approaches but perhaps most effectively through applications for bacterial artificial chromosome (BAC) libraries. Individual BAC clones carry 100–200 kb of seque...

  10. Haploidization via Chromosome Elimination: Means and Mechanisms.

    Science.gov (United States)

    Ishii, Takayoshi; Karimi-Ashtiyani, Raheleh; Houben, Andreas

    2016-04-29

    The ability to generate haploids and subsequently induce chromosome doubling significantly accelerates the crop breeding process. Haploids have been induced through the generation of plants from haploid tissues (in situ gynogenesis and androgenesis) and through the selective loss of a parental chromosome set via inter- or intraspecific hybridization. Here, we focus on the mechanisms responsible for this selective chromosome elimination. CENH3, a variant of the centromere-specific histone H3, has been exploited to create an efficient method of haploid induction, and we discuss this approach in some detail. Parallels have been drawn with chromosome-specific elimination, which occurs as a normal part of differentiation and sex determination in many plant and animal systems. PMID:26772657

  11. Cancer chromosomal instability: therapeutic and diagnostic challenges

    OpenAIRE

    McGranahan, Nicholas; Burrell, Rebecca A.; Endesfelder, David; Novelli, Marco R; Swanton, Charles

    2012-01-01

    This review provides a much-needed translational perspective into the issue of aneuploidy and chromosomal instability, discussing the prognostic value of CIN assessment in human tumours, methods to analyze it and how it could be therapeutically targeted.

  12. Lattice animal model of chromosome organization

    Science.gov (United States)

    Iyer, Balaji V. S.; Arya, Gaurav

    2012-07-01

    Polymer models tied together by constraints of looping and confinement have been used to explain many of the observed organizational characteristics of interphase chromosomes. Here we introduce a simple lattice animal representation of interphase chromosomes that combines the features of looping and confinement constraints into a single framework. We show through Monte Carlo simulations that this model qualitatively captures both the leveling off in the spatial distance between genomic markers observed in fluorescent in situ hybridization experiments and the inverse decay in the looping probability as a function of genomic separation observed in chromosome conformation capture experiments. The model also suggests that the collapsed state of chromosomes and their segregation into territories with distinct looping activities might be a natural consequence of confinement.

  13. Chromosome studies in the genus Jatropha L.

    Directory of Open Access Journals (Sweden)

    R.Sasikala and M.Paramathma

    2010-07-01

    Full Text Available The inflorescences of ten species of the genus Jatropha were fixed in Cornoy’s fluid (6:3:1. Acetocarmine stain (2% wasused for staining the pollen mother cells. Seven species exhibited 11 bivalents and 2n =22 and x=11. But the two otherspecies, J.villosa var. villosa and J.villosa var. ramnadensis showed only 10 bivalents and 2n number of 20 chromosomesand x=10. The study concluded the occurrence of two kinds of haploid chromosome numbers of n =10 and n =11. ExceptJatropha tanjorensis, cytological investigation in all species exhibited normal and complete pairing and bivalent formationin metaphase I and equal separation of chromosome in anaphase and indicated that the course of meiosis was normal.Jatropha tanjorensis did not exhibit normal course of meiosis and no proper count of chromosomes could be made. Presentchromosomal studies in Jatropha revealed the existence of two basic chromosomes numbers x = 5 and x = 6.

  14. System for the analysis of plant chromosomes

    International Nuclear Information System (INIS)

    The paper describes a computer system for the automation workers of recognition analysis and interpretation of plant chromosomes. This system permit to carry out the analysis in a more comfortable and faster way, using the image processing techniques

  15. Chromosomal instability determines taxane response

    DEFF Research Database (Denmark)

    Swanton, C.; Nicke, B.; Schuett, M.;

    2009-01-01

    Microtubule-stabilizing (MTS) agents, such as taxanes, are important chemotherapeutics with a poorly understood mechanism of action. We identified a set of genes repressed in multiple cell lines in response to MTS agents and observed that these genes are overexpressed in tumors exhibiting...

  16. A chromosome-centric human proteome project (C-HPP) to characterize the sets of proteins encoded in chromosome 17.

    Science.gov (United States)

    Liu, Suli; Im, Hogune; Bairoch, Amos; Cristofanilli, Massimo; Chen, Rui; Deutsch, Eric W; Dalton, Stephen; Fenyo, David; Fanayan, Susan; Gates, Chris; Gaudet, Pascale; Hincapie, Marina; Hanash, Samir; Kim, Hoguen; Jeong, Seul-Ki; Lundberg, Emma; Mias, George; Menon, Rajasree; Mu, Zhaomei; Nice, Edouard; Paik, Young-Ki; Uhlen, Mathias; Wells, Lance; Wu, Shiaw-Lin; Yan, Fangfei; Zhang, Fan; Zhang, Yue; Snyder, Michael; Omenn, Gilbert S; Beavis, Ronald C; Hancock, William S

    2013-01-01

    We report progress assembling the parts list for chromosome 17 and illustrate the various processes that we have developed to integrate available data from diverse genomic and proteomic knowledge bases. As primary resources, we have used GPMDB, neXtProt, PeptideAtlas, Human Protein Atlas (HPA), and GeneCards. All sites share the common resource of Ensembl for the genome modeling information. We have defined the chromosome 17 parts list with the following information: 1169 protein-coding genes, the numbers of proteins confidently identified by various experimental approaches as documented in GPMDB, neXtProt, PeptideAtlas, and HPA, examples of typical data sets obtained by RNASeq and proteomic studies of epithelial derived tumor cell lines (disease proteome) and a normal proteome (peripheral mononuclear cells), reported evidence of post-translational modifications, and examples of alternative splice variants (ASVs). We have constructed a list of the 59 "missing" proteins as well as 201 proteins that have inconclusive mass spectrometric (MS) identifications. In this report we have defined a process to establish a baseline for the incorporation of new evidence on protein identification and characterization as well as related information from transcriptome analyses. This initial list of "missing" proteins that will guide the selection of appropriate samples for discovery studies as well as antibody reagents. Also we have illustrated the significant diversity of protein variants (including post-translational modifications, PTMs) using regions on chromosome 17 that contain important oncogenes. We emphasize the need for mandated deposition of proteomics data in public databases, the further development of improved PTM, ASV, and single nucleotide variant (SNV) databases, and the construction of Web sites that can integrate and regularly update such information. In addition, we describe the distribution of both clustered and scattered sets of protein families on the

  17. Elasticity of Substitution and Antidumping Measures

    DEFF Research Database (Denmark)

    Drud Hansen, Jørgen; Meinen, Philipp; Nielsen, Jørgen Ulff-Møller

    Abstract This paper analyzes the role of the elasticity of substitution for anti-dumping decisions across countries. In monopolistic competition models with cost heterogeneous firms across countries, price differences vary inversely with the elasticity of substitution. Anti-dumping duties should...... therefore also vary inversely with the elasticity of substitution at least for countries which have a strong focus on prices in the determination of their anti-dumping measures. We test this for ten countries from 1990 to 2009 using data on anti-dumping from Chad Bown (2010) and US-data at 8-digit level...... in our empirical investigation support the predicted role of the elasticity of substitution as we find a significant negative relation between the elasticity of substitution and the final anti-dumping duties for the ‘lesser duty rule’ group of countries. The countries which do not follow the ‘lesser duty...

  18. Substitution between cars within the household

    DEFF Research Database (Denmark)

    De Borger, Bruno; Mulalic, Ismir; Rouwendal, Jan

    2016-01-01

    In this paper we study the demand for car kilometres in two-car households, focusing on the substitution between cars of different fuel efficiency in response to fuel price changes. We use a large sample of detailed Danish data on two-car households to estimate – for each car owned by the household...... – own and cross-price effects of increases in fuel costs per kilometre. The empirical results show that failure to capture substitution between cars within the household can result in substantial misspecification biases. Ignoring substitution, the basic model yielded fuel price elasticities of 0.98 and...... 1.41 for the primary and secondary cars, respectively. Accounting for substitution effects, these figures reduce to, respectively, 0.32 and 0.45. Consistent with substitution behaviour, we find that the fuel price elasticity of fuel demand exceeds the elasticity of kilometre demands with respect to...

  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. Detection of Chromosomal Structural Alterations in Single Cells by SNP Arrays: A Systematic Survey of Amplification Bias and Optimized Workflow

    Science.gov (United States)

    Iwamoto, Kazuya; Bundo, Miki; Ueda, Junko; Nakano, Yoko; Ukai, Wataru; Hashimoto, Eri; Saito, Toshikazu; Kato, Tadafumi

    2007-01-01

    Background In single-cell human genome analysis using whole-genome amplified product, a strong amplification bias involving allele dropout and preferential amplification hampers the quality of results. Using an oligonucleotide single nucleotide polymorphism (SNP) array, we systematically examined the nature of this amplification bias, including frequency, degree, and preference for genomic location, and we assessed the effects of this amplification bias on subsequent genotype and chromosomal copy number analyses. Methodology/Principal Findings We found a large variability in amplification bias among the amplified products obtained by multiple displacement amplification (MDA), and this bias had a severe effect on the genotype and chromosomal copy number analyses. We established optimal experimental conditions for pre-screening for high-quality amplified products, processing array data, and analyzing chromosomal structural alterations. Using this optimized protocol, we successfully detected previously unidentified chromosomal structural alterations in single cells from a lymphoblastoid cell line. These alterations were subsequently confirmed by karyotype analysis. In addition, we successfully obtained reproducible chromosomal copy number profiles of single cells from the cell line with a complex karyotype, indicating the applicability and potential of our optimized workflow. Conclusions/Significance Our results suggest that the quality of amplification products should be critically assessed before using them for genomic analyses. The method of MDA-based whole-genome amplification followed by SNP array analysis described here will be useful for exploring chromosomal alterations in single cells. PMID:18074030