scispace - formally typeset
Search or ask a question
Topic

Centromere

About: Centromere is a research topic. Over the lifetime, 5517 publications have been published within this topic receiving 287403 citations. The topic is also known as: GO:0000775 & chromosome, centric region.


Papers
More filters
Journal ArticleDOI
01 Dec 1992-Genetics
TL;DR: Currently tomato and potato are among the most thoroughly mapped eukaryotic species and the availability of high density molecular linkage maps should facilitate chromosome walking, quantitative trait mapping, marker-assisted breeding and evolutionary studies in these two important and well studied crop species.
Abstract: High density molecular linkage maps, comprised of more than 1000 markers with an average spacing between markers of approximately 1.2 cM (ca. 900 kb), have been constructed for the tomato and potato genomes. As the two maps are based on a common set of probes, it was possible to determine, with a high degree of precision, the breakpoints corresponding to 5 chromosomal inversions that differentiate the tomato and potato genomes. All of the inversions appear to have resulted from single breakpoints at or near the centromeres of the affected chromosomes, the result being the inversion of entire chromosome arms. While the crossing over rate among chromosomes appears to be uniformly distributed with respect to chromosome size, there is tremendous heterogeneity of crossing over within chromosomes. Regions of the map corresponding to centromeres and centromeric heterochromatin, and in some instances telomeres, experience up to 10-fold less recombination than other areas of the genome. Overall, 28% of the mapped loci reside in areas of putatively suppressed recombination. This includes loci corresponding to both random, single copy genomic clones and transcribed genes (detected with cDNA probes). The extreme heterogeneity of crossing over within chromosomes has both practical and evolutionary implications. Currently tomato and potato are among the most thoroughly mapped eukaryotic species and the availability of high density molecular linkage maps should facilitate chromosome walking, quantitative trait mapping, marker-assisted breeding and evolutionary studies in these two important and well studied crop species.

1,636 citations

Journal ArticleDOI
03 Oct 1997-Cell
TL;DR: Three chromosmal proteins that prevent premature separation of sister chromatids in yeast are described, two of which are members of the SMC family, which are putative ATPases with coiled-coil domains.

1,545 citations

Journal ArticleDOI
22 Jul 2004-Nature
TL;DR: Using microarray analysis, it is shown that heterochromatin in Arabidopsis is determined by transposable elements and related tandem repeats, under the control of the chromatin remodelling ATPase DDM1 (Decrease in DNA Methylation 1).
Abstract: Heterochromatin has been defined as deeply staining chromosomal material that remains condensed in interphase, whereas euchromatin undergoes de-condensation. Heterochromatin is found near centromeres and telomeres, but interstitial sites of heterochromatin (knobs) are common in plant genomes and were first described in maize. These regions are repetitive and late-replicating. In Drosophila, heterochromatin influences gene expression, a heterochromatin phenomenon called position effect variegation. Similarities between position effect variegation in Drosophila and gene silencing in maize mediated by "controlling elements" (that is, transposable elements) led in part to the proposal that heterochromatin is composed of transposable elements, and that such elements scattered throughout the genome might regulate development. Using microarray analysis, we show that heterochromatin in Arabidopsis is determined by transposable elements and related tandem repeats, under the control of the chromatin remodelling ATPase DDM1 (Decrease in DNA Methylation 1). Small interfering RNAs (siRNAs) correspond to these sequences, suggesting a role in guiding DDM1. We also show that transposable elements can regulate genes epigenetically, but only when inserted within or very close to them. This probably accounts for the regulation by DDM1 and the DNA methyltransferase MET1 of the euchromatic, imprinted gene FWA, as its promoter is provided by transposable-element-derived tandem repeats that are associated with siRNAs.

1,199 citations

Journal ArticleDOI
10 Aug 2001-Science
TL;DR: Incompatibilities between rapidly evolving Centromeric components may be responsible for both the organization of centromeric regions and the reproductive isolation of emerging species.
Abstract: Every eukaryotic chromosome has a centromere, the locus responsible for poleward movement at mitosis and meiosis. Although conventional loci are specified by their DNA sequences, current evidence favors a chromatin-based inheritance mechanism for centromeres. The chromosome segregation machinery is highly conserved across all eukaryotes, but the DNA and protein components specific to centromeric chromatin are evolving rapidly. Incompatibilities between rapidly evolving centromeric components may be responsible for both the organization of centromeric regions and the reproductive isolation of emerging species.

1,128 citations

Journal ArticleDOI
27 Sep 2002-Science
TL;DR: It is demonstrated that a centromere-homologous repeat present at the silent mating-type region is sufficient for heterochromatin formation at an ectopic site, and that its repressive capacity is mediated by components of the RNA interference (RNAi) machinery.
Abstract: The higher-order assembly of chromatin imposes structural organization on the genetic information of eukaryotes and is thought to be largely determined by posttranslational modification of histone tails. Here, we study a 20-kilobase silent domain at the mating-type region of fission yeast as a model for heterochromatin formation. We find that, although histone H3 methylated at lysine 9 (H3 Lys9) directly recruits heterochromatin protein Swi6/HP1, the critical determinant for H3 Lys9 methylation to spread in cis and to be inherited through mitosis and meiosis is Swi6 itself. We demonstrate that a centromere-homologous repeat (cenH) present at the silent mating-type region is sufficient for heterochromatin formation at an ectopic site, and that its repressive capacity is mediated by components of the RNA interference (RNAi) machinery. Moreover, cenH and the RNAi machinery cooperate to nucleate heterochromatin assembly at the endogenous mat locus but are dispensable for its subsequent inheritance. This work defines sequential requirements for the initiation and propagation of regional heterochromatic domains.

918 citations


Network Information
Related Topics (5)
Chromatin
50.7K papers, 2.7M citations
89% related
Gene
211.7K papers, 10.3M citations
85% related
Mutation
45.2K papers, 2.6M citations
84% related
Histone
28.8K papers, 1.5M citations
84% related
Exon
38.3K papers, 1.7M citations
83% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023179
2022282
2021185
2020208
2019206
2018183