Caenorhabditis elegans chromosome arms are anchored to the nuclear membrane via discontinuous association with LEM-2.
Caenorhabditis elegans chromosome arms are anchored to the nuclear membrane via discontinuous association with LEM-2.
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DOI：
10.1186/gb-2010-11-12-r120
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发表时间：
2010
期刊：
影响因子：
12.3
通讯作者：
Lieb JD
中科院分区：
文献类型：
--
作者：
Ikegami K;Egelhofer TA;Strome S;Lieb JD
尽管秀丽线虫是第一个拥有完全测序基因组的多细胞生物体，但这个基因组在细胞核内是如何排列的尚不清楚。我们用染色质免疫沉淀法测定了线虫混合期胚胎中与核跨膜蛋白LEM-2相关的基因组区域。每个常染色体臂上的几个百万碱基的大区域与LEM-2有关。每个常染色体的中心大部分没有这种相互作用，这表明它们基本上是从核膜环状分布的。只有X染色体的左端与核膜相连。在更细的尺度上，大的膜相关结构域由LEM-2缔合的较小的亚结构域组成。这些亚区的特征是高重复密度、低基因密度、高水平的H3K27三甲基化和沉默基因。这些亚区被含有高活性基因的空隙点缀。移位到染色体中心的染色体臂保留了与LEM-2的关联，尽管融合点附近的关联略有减少。局部DNA或染色质属性是与核膜相互作用的主要决定因素，染色体上的位置起着次要作用。LEM-2相关区域之间的小间隙中的基因往往高表达，这表明这些小间隙特别适合高效转录。虽然我们的数据来自混合期胚胎中细胞类型的融合，但结果表明线虫染色体在细胞核内的空间排列模式。
Although Caenorhabditis elegans was the first multicellular organism with a completely sequenced genome, how this genome is arranged within the nucleus is not known. We determined the genomic regions associated with the nuclear transmembrane protein LEM-2 in mixed-stage C. elegans embryos via chromatin immunoprecipitation. Large regions of several megabases on the arms of each autosome were associated with LEM-2. The center of each autosome was mostly free of such interactions, suggesting that they are largely looped out from the nuclear membrane. Only the left end of the X chromosome was associated with the nuclear membrane. At a finer scale, the large membrane-associated domains consisted of smaller subdomains of LEM-2 associations. These subdomains were characterized by high repeat density, low gene density, high levels of H3K27 trimethylation, and silent genes. The subdomains were punctuated by gaps harboring highly active genes. A chromosome arm translocated to a chromosome center retained its association with LEM-2, although there was a slight decrease in association near the fusion point. Local DNA or chromatin properties are the main determinant of interaction with the nuclear membrane, with position along the chromosome making a minor contribution. Genes in small gaps between LEM-2 associated regions tend to be highly expressed, suggesting that these small gaps are especially amenable to highly efficient transcription. Although our data are derived from an amalgamation of cell types in mixed-stage embryos, the results suggest a model for the spatial arrangement of C. elegans chromosomes within the nucleus.
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影响因子：
9.8
作者：
Hillier LW;Miller RD;Baird SE;Chinwalla A;Fulton LA;Koboldt DC;Waterston RH
通讯作者：
Waterston RH
DOI：
10.1083/jcb.145.6.1119
发表时间：
1999-06-14
期刊：
The Journal of cell biology
影响因子：
--
作者：
Croft JA;Bridger JM;Boyle S;Perry P;Teague P;Bickmore WA
通讯作者：
Bickmore WA
影响因子：
64.8
作者：
Guelen, Lars;Pagie, Ludo;van Steensel, Bas
通讯作者：
van Steensel, Bas
影响因子：
7.8
作者：
HOCHSTRASSER, M;MATHOG, D;GRUENBAUM, Y;SAUMWEBER, H;SEDAT, JW
通讯作者：
SEDAT, JW
影响因子：
30.8
作者：
Ercan, Sevinc;Giresi, Paul G.;Lieb, Jason D.
通讯作者：
Lieb, Jason D.