Analysis of Chromatin Structure in the Control Regions of the <Emphasis Type="Italic">Chlamydomonas HSP70A</Emphasis> and <Emphasis Type="Italic">RBCS2</Emphasis> Genes |
| |
Authors: | Mukesh?Lodha Email author" target="_blank">Michael?SchrodaEmail author |
| |
Institution: | 1.Institute of Biology II, Plant Biochemistry,University of Freiburg,Freiburg,Germany |
| |
Abstract: | We have used DNaseI and micrococcal nuclease sensitivity assays to determine the chromatin structures in the control regions
of the Chlamydomonas reinhardtii HSP70A and RBCS2 genes. Both genes appear to be organized into nucleosome arrays, which exhibit shorter nucleosome repeat lengths than bulk
chromatin. In HSP70A we have identified up to four confined DNaseI hypersensitive sites, three of them localize to the promoter region, a fourth
one to the fourth intron. Three hypersensitive sites map close to putative heat shock elements, one close to a CCAAT-box.
All hypersensitive sites are located to internucleosomal linkers. Alternative nucleosome positions at half-nucleosomal phasing
were constitutively detected in the HSP70A promoter region, indicating local chromatin remodelling. Upon heat shock, dramatic changes in the nucleosome structure of
HSP70A were detected that particularly affected the promoter, but also a region within the fourth intron. In contrast, light induction
entailed no change in HSP70A chromatin. In the RBCS2 control region we identified a strong DNaseI hypersensitive site that maps close to a CCAAT-box. This site forms the boundary
of a nucleosome array with a region of ~700 bp apparently devoid of nucleosomes. This study demonstrates that chromatin structure
may be determined readily at fairly high resolution in Chlamydomonas, suggesting this organism as a well-suited model for studying the role of chromatin structure on gene expression in photosynthetic
eukaryotes. |
| |
Keywords: | chromatin DNaseI sensitivity HSP70 micrococcal nuclease sensitivity nucleosome repeat length RBCS2 |
本文献已被 PubMed SpringerLink 等数据库收录! |
|