Localization and characteristics of DNA underreplication zone in the 75C region of intercalary heterochromatin in Drosophila melanogaster polytene chromosomes
Localization and characteristics of DNA underreplication zone in the 75C region of intercalary heterochromatin in Drosophila melanogaster polytene chromosomes
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DOI：
10.1007/s00412-009-0232-6
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发表时间：
2009-12-01
期刊：
影响因子：
1.6
通讯作者：
Zhimulev, Igor F.
中科院分区：
文献类型：
--
作者：
Andreyenkova, Natalya G.;Kokoza, Elena B.;Zhimulev, Igor F.
在果蝇的多线染色体中，中间异染色质区域分散在常染色质臂中。在这里，我们提出的数据上的第一个精细分析的个人间异染色质区域，75 C1 -2，位于3L染色体。通过使用电子显微镜，我们证明了这个区域出现三个紧密相邻的凝聚带。通过已知断裂点的染色体重排在物理图上定位该区域，表明该区域的长度约为445 kb。虽然SUUR蛋白似乎与整个75 C1 -2区域结合，但该区域的近端部分完全多聚化，因此DNA复制不足区是不对称的，位于该区域的远侧一半。最后，我们推测，果蝇多线染色体的插入异染色质区域被组织成三种不同的类型相对于本地化的复制不足区。
In Drosophila polytene chromosomes, regions of intercalary heterochromatin are scattered throughout the euchromatic arms. Here, we present data on the first fine analysis of the individual intercalary heterochromatin region, 75C1-2, located in the 3L chromosome. By using electron microscopy, we demonstrated that this region appears as three closely adjacent condensed bands. Mapping of the region on the physical map by means of the chromosomal rearrangements with known breakpoints showed that the length of the region is about 445 kb. Although it seems that the SUUR protein binds to the whole 75C1-2 region, the proximal part of the region is fully polytenized, so the DNA underreplication zone is asymmetric and located in the distal half of the region. Finally, we speculate that intercalary heterochromatin regions of Drosophila polytene chromosomes are organized into three different types with respect to the localization of the underreplication zone.