Chromosoma最新文献_第10页

Dampened X-chromosomes in human pluripotent stem cells: dampening or erasure of X-upregulation? 人类多能干细胞中被抑制的x染色体:抑制还是消除x上调?

IF 1.6 4区生物学

Chromosoma Pub Date : 2020-06-01 Epub Date: 2019-07-04 DOI: 10.1007/s00412-019-00717-5

Harman Kaur, Pavithra Rv, Srimonta Gayen

引用次数: 7

Copy-number variation introduced by long transgenes compromises mouse male fertility independently of pachytene checkpoints. 长转基因引入的拷贝数变异独立于粗线蛋白检查点影响小鼠雄性生育力。

IF 1.6 4区生物学

Chromosoma Pub Date : 2020-03-01 Epub Date: 2020-01-15 DOI: 10.1007/s00412-019-00730-8

Ondrej Mihola, Tatyana Kobets, Klara Krivankova, Eliska Linhartova, Srdjan Gasic, John C Schimenti, Zdenek Trachtulec

{"title":"Copy-number variation introduced by long transgenes compromises mouse male fertility independently of pachytene checkpoints.","authors":"Ondrej Mihola, Tatyana Kobets, Klara Krivankova, Eliska Linhartova, Srdjan Gasic, John C Schimenti, Zdenek Trachtulec","doi":"10.1007/s00412-019-00730-8","DOIUrl":"https://doi.org/10.1007/s00412-019-00730-8","url":null,"abstract":"Long transgenes are often used in mammalian genetics, e.g., to rescue mutations in large genes. In the course of experiments addressing the genetic basis of hybrid sterility caused by meiotic defects in mice bearing different alleles of Prdm9, we discovered that introduction of copy-number variation (CNV) via two independent insertions of long transgenes containing incomplete Prdm9 decreased testicular weight and epididymal sperm count. Transgenic animals displayed increased occurrence of seminiferous tubules with apoptotic cells at 18 days postpartum (dpp) corresponding to late meiotic prophase I, but not at 21 dpp. We hypothesized that long transgene insertions could cause asynapsis, but the immunocytochemical data revealed that the adult transgenic testes carried a similar percentage of asynaptic pachytene spermatocytes as the controls. These transgenic spermatocytes displayed less crossovers but similar numbers of unrepaired meiotic breaks. Despite slightly increased frequency of metaphase I spermatocytes with univalent chromosome(s) and reduced numbers of metaphase II spermatocytes, cytological studies did not reveal increased apoptosis in tubules containing the metaphase spermatocytes, but found an increased percentage of tubules carrying apoptotic spermatids. Sperm counts of subfertile animals inversely correlated with the transcription levels of the Psmb1 gene encoded within these two transgenes. The effect of the transgenes was dependent on sex and genetic background. Our results imply that the fertility of transgenic hybrid animals is not compromised by the impaired meiotic synapsis of homologous chromosomes, but can be negatively influenced by the increased expression of the introduced genes.","PeriodicalId":10248,"journal":{"name":"Chromosoma","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00412-019-00730-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37544832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Eight million years of maintained heterozygosity in chromosome homologs of cercopithecine monkeys. 猴的染色体同源物维持了800万年的杂合性。

IF 1.6 4区生物学

Chromosoma Pub Date : 2020-03-01 Epub Date: 2020-01-10 DOI: 10.1007/s00412-020-00731-y

Doron Tolomeo, Oronzo Capozzi, Giorgia Chiatante, Luca Sineo, Takafumi Ishida, Nicoletta Archidiacono, Mariano Rocchi, Roscoe Stanyon

{"title":"Eight million years of maintained heterozygosity in chromosome homologs of cercopithecine monkeys.","authors":"Doron Tolomeo, Oronzo Capozzi, Giorgia Chiatante, Luca Sineo, Takafumi Ishida, Nicoletta Archidiacono, Mariano Rocchi, Roscoe Stanyon","doi":"10.1007/s00412-020-00731-y","DOIUrl":"https://doi.org/10.1007/s00412-020-00731-y","url":null,"abstract":"In the Cercopithecini ancestor two chromosomes, homologous to human chromosomes 20 and 21, fused to form the Cercopithecini specific 20/21 association. In some individuals from the genus Cercopithecus, this association was shown to be polymorphic for the position of the centromere, suggesting centromere repositioning events. We set out to test this hypothesis by defining the evolutionary history of the 20/21 association in four Cercopithecini species from three different genera. The marker order of the various 20/21 associations was established using molecular cytogenetic techniques, including an array of more than 100 BACs. We discovered that five different forms of the 20/21 association were present in the four studied Cercopithecini species. Remarkably, in the two Cercopithecus species, we found individuals in which one homolog conserved the ancestral condition, but the other homolog was highly rearranged. The phylogenetic analysis showed that the heterozygosity in these two species originated about 8 million years ago and was maintained for this entire arc of time, surviving multiple speciation events. Our report is a remarkable extension of Dobzhansky's pioneering observation in Drosophila concerning the maintenance of chromosomal heterozygosity due to selective advantage. Dobzhansky's hypothesis recently received strong support in a series of detailed reports on the fruit fly genome. Our findings are first extension to primates, indeed to Old World monkeys phylogenetically close to humans of an analogous situation. Our results have important implications for hypotheses on how chromosome rearrangements, selection, and speciation are related.","PeriodicalId":10248,"journal":{"name":"Chromosoma","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00412-020-00731-y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37532961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Heterochromatin formation in Drosophila requires genome-wide histone deacetylation in cleavage chromatin before mid-blastula transition in early embryogenesis. 果蝇异染色质的形成需要在早期胚胎发育中期母细胞过渡之前裂解染色质中的全基因组组蛋白去乙酰化。

IF 2.5 4区生物学

Chromosoma Pub Date : 2020-03-01 Epub Date: 2020-01-16 DOI: 10.1007/s00412-020-00732-x

Matthias Walther, Sandy Schrahn, Veiko Krauss, Sandro Lein, Jeannette Kessler, Thomas Jenuwein, Gunter Reuter

{"title":"Heterochromatin formation in Drosophila requires genome-wide histone deacetylation in cleavage chromatin before mid-blastula transition in early embryogenesis.","authors":"Matthias Walther, Sandy Schrahn, Veiko Krauss, Sandro Lein, Jeannette Kessler, Thomas Jenuwein, Gunter Reuter","doi":"10.1007/s00412-020-00732-x","DOIUrl":"10.1007/s00412-020-00732-x","url":null,"abstract":"Su(var) mutations define epigenetic factors controlling heterochromatin formation and gene silencing in Drosophila. Here, we identify SU(VAR)2-1 as a novel chromatin regulator that directs global histone deacetylation during the transition of cleavage chromatin into somatic blastoderm chromatin in early embryogenesis. SU(VAR)2-1 is heterochromatin-associated in blastoderm nuclei but not in later stages of development. In larval polytene chromosomes, SU(VAR)2-1 is a band-specific protein. SU(VAR)2-1 directs global histone deacetylation by recruiting the histone deacetylase RPD3. In Su(var)2-1 mutants H3K9, H3K27, H4K8 and H4K16 acetylation shows elevated levels genome-wide and heterochromatin displays aberrant histone hyper-acetylation. Whereas H3K9me2- and HP1a-binding appears unaltered, the heterochromatin-specific H3K9me2S10ph composite mark is impaired in heterochromatic chromocenters of larval salivary polytene chromosomes. SU(VAR)2-1 contains an NRF1/EWG domain and a C2HC zinc-finger motif. Our study identifies SU(VAR)2-1 as a dosage-dependent, heterochromatin-initiating SU(VAR) factor, where the SU(VAR)2-1-mediated control of genome-wide histone deacetylation after cleavage and before mid-blastula transition (pre-MBT) is required to enable heterochromatin formation.","PeriodicalId":10248,"journal":{"name":"Chromosoma","volume":null,"pages":null},"PeriodicalIF":2.5,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7021753/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37554395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Species-specific abundant retrotransposons elucidate the genomic composition of modern sugarcane cultivars. 物种特异的大量反转录转座子阐明了现代甘蔗品种的基因组组成。

IF 1.6 4区生物学

Chromosoma Pub Date : 2020-03-01 Epub Date: 2019-12-17 DOI: 10.1007/s00412-019-00729-1

Yongji Huang, Hong Chen, Jinlei Han, Ya Zhang, Shulin Ma, Guangrun Yu, Zonghua Wang, Kai Wang

{"title":"Species-specific abundant retrotransposons elucidate the genomic composition of modern sugarcane cultivars.","authors":"Yongji Huang, Hong Chen, Jinlei Han, Ya Zhang, Shulin Ma, Guangrun Yu, Zonghua Wang, Kai Wang","doi":"10.1007/s00412-019-00729-1","DOIUrl":"https://doi.org/10.1007/s00412-019-00729-1","url":null,"abstract":"Modern sugarcane cultivars are highly polyploid and derived from the hybridization of Saccharum officinarum and S. spontaneum, thus leading to singularly complex genomes. The complex genome has hindered the study of genomic structures. Here, we adopted a computational strategy to isolate highly repetitive and abundant sequences in either S. officinarum or S. spontaneum and isolated four S. spontaneum-enriched retrotransposons. Fluorescence in situ hybridization (FISH) assays with these repetitive DNA sequences generated whole-genome painting signals for S. spontaneum but not for S. officinarum. We demonstrated that these repetitive sequence-based probes distinguish the parental S. spontaneum genome in hybrids derived from crosses between it and S. officinarum. A cytological analysis of 14 modern sugarcane cultivars revealed that the percentages of chromosomes with introgressive S. spontaneum fragments ranged from 11.9 to 40.9% and substantially exceeded those determined for previously investigated cultivars (5-13%). The comparatively higher percentages of introgressive S. spontaneum fragments detected in the aforementioned cultivars indicate frequent recombination between parental genomes. Here, we present the application of our strategy to isolate species-specific cytological markers. This information may help to elucidate complex plant genomic structures and trace their evolutionary histories.","PeriodicalId":10248,"journal":{"name":"Chromosoma","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00412-019-00729-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37467344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Faint gray bands in Drosophila melanogaster polytene chromosomes are formed by coding sequences of housekeeping genes 果蝇多线染色体上的淡灰色条带是由家政基因的编码序列形成的

IF 1.6 4区生物学

Chromosoma Pub Date : 2019-12-09 DOI: 10.1007/s00412-019-00728-2

O. Demakova, S. A. Demakov, L. Boldyreva, T. Zykova, V. Levitsky, V. Semeshin, G. Pokholkova, Darya S. Sidorenko, Fedor P. Goncharov, E. Belyaeva, I. Zhimulev

引用次数: 4

A role of the Trx-G complex in Cid/CENP-A deposition at Drosophila melanogaster centromeres. Trx-G复合物在果蝇着丝粒中Cid/CENP-A沉积中的作用。

IF 1.6 4区生物学

Chromosoma Pub Date : 2019-12-01 Epub Date: 2019-06-16 DOI: 10.1007/s00412-019-00711-x

Lucia Piacentini, Marcella Marchetti, Elisabetta Bucciarelli, Assunta Maria Casale, Ugo Cappucci, Paolo Bonifazi, Fioranna Renda, Laura Fanti

{"title":"A role of the Trx-G complex in Cid/CENP-A deposition at Drosophila melanogaster centromeres.","authors":"Lucia Piacentini, Marcella Marchetti, Elisabetta Bucciarelli, Assunta Maria Casale, Ugo Cappucci, Paolo Bonifazi, Fioranna Renda, Laura Fanti","doi":"10.1007/s00412-019-00711-x","DOIUrl":"https://doi.org/10.1007/s00412-019-00711-x","url":null,"abstract":"Centromeres are epigenetically determined chromatin structures that specify the assembly site of the kinetochore, the multiprotein machinery that binds microtubules and mediates chromosome segregation during mitosis and meiosis. The centromeric protein A (CENP-A) and its Drosophila orthologue centromere identifier (Cid) are H3 histone variants that replace the canonical H3 histone in centromeric nucleosomes of eukaryotes. CENP-A/Cid is required for recruitment of other centromere and kinetochore proteins and its deficiency disrupts chromosome segregation. Despite the many components that are known to cooperate in centromere function, the complete network of factors involved in CENP-A recruitment remains to be defined. In Drosophila, the Trx-G proteins localize along the heterochromatin with specific patterns and some of them localize to the centromeres of all chromosomes. Here, we show that the Trx, Ash1, and CBP proteins are required for the correct chromosome segregation and that Ash1 and CBP mediate for Cid/CENP-A recruitment at centromeres through post-translational histone modifications. We found that centromeric H3 histone is consistently acetylated in K27 by CBP and that nej and ash1 silencing respectively causes a decrease in H3K27 acetylation and H3K4 methylation along with an impairment of Cid loading.","PeriodicalId":10248,"journal":{"name":"Chromosoma","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s00412-019-00711-x","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37332478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Acknowledgement to reviewers 审稿人致谢

IF 1.6 4区生物学

Chromosoma Pub Date : 2019-12-01 DOI: 10.1007/BF00292793

G. Casoni, S. Cavaliere, S. K. Chhabra, P. Chhajed, T. Çiftçi, A. Aggarwal, K. Amjadi, J. Annema, S. Bilaçeroğlu, Vincent Cottin

引用次数: 0

Genetic and epigenetic effects on centromere establishment 着丝粒建立的遗传和表观遗传效应

IF 1.6 4区生物学

Chromosoma Pub Date : 2019-11-28 DOI: 10.1007/s00412-019-00727-3

Y. Ling, Zhongyang Lin, K. Yuen

引用次数: 5

Acknowledgement to reviewers 审稿人致谢

IF 1.6 4区生物学

Chromosoma Pub Date : 2019-11-01 DOI: 10.1007/BF00352300

Editorial Office

引用次数: 0