Intercalary heterochromatin in polytene chromosomes of Drosophila melanogaster

被引：26

作者：

Belyaeva, E. S. ^{[1
]}

Andreyeva, E. N. ^{[1
]}

Belyakin, S. N. ^{[1
]}

Volkova, E. I. ^{[1
]}

Zhimulev, I. F. ^{[1
]}

机构：

[1] Inst Cytol & Genet, Novosibirsk 630090, Russia

来源：

CHROMOSOMA | 2008年 / 117卷 / 05期

基金：

俄罗斯基础研究基金会;

关键词：

D O I：

10.1007/s00412-008-0163-7

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Intercalary heterochromatin consists of extended chromosomal domains which are interspersed throughout the euchromatin and contain silent genetic material. These domains comprise either clusters of functionally unrelated genes or tandem gene duplications and possibly stretches of noncoding sequences. Strong repression of genetic activity means that intercalary heterochromatin displays properties that are normally attributable to classic pericentric heterochromatin: high compaction, late replication and underreplication in polytene chromosomes, and the presence of heterochromatin-specific proteins. Late replication and underreplication occurs when the suppressor of underreplication protein is present in intercalary heterochromatic regions. Intercalary heterochromatin underreplication in polytene chromosomes results in free double-stranded ends of DNA molecules; ligation of these free ends is the most likely mechanism for ectopic pairing between intercalary heterochromatic and pericentric heterochromatic regions. No support has been found for the view that the frequency of chromosome aberrations is elevated in intercalary heterochromatin.

引用

页码：411 / 418

页数：8

共 57 条

[1] High-resolution analysis of Drosophila heterochromatin organization using SuUR Su(var)3-9 double mutants [J].