tailieunhanh - Báo cáo y học: "GC- and AT-rich chromatin domains differ in conformation and histone modification status and are differentially modulated by Rpd3"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Critical Care giúp cho các bạn có thêm kiến thức về ngành y học đề tài: GC- and AT-rich chromatin domains differ in conformation and histone modification status and are differentially modulated by Rpd3p. | Open Access Research GC- and AT-rich chromatin domains differ in conformation and histone modification status and are differentially modulated by Rpd3p Job Dekker Address Program in Gene Function and Expression and Department of Biochemistry and Molecular Pharmacology University of Massachusetts Medical School Plantation Street Worcester MA 01605-4321 USA. Email Published 18 June 2007 Received 13 February 2007 Genome Biology 2007 8 RII6 doi gb-2007-8-6-rl 16 Accepted 18 June 2007 The electronic version of this article is the complete one and can be found online at http 2007 8 6 R116 2007 Dekker licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background Base-composition varies throughout the genome and is related to organization of chromosomes in distinct domains isochores . Isochore domains differ in gene expression levels replication timing levels of meiotic recombination and chromatin structure. The molecular basis for these differences is poorly understood. Results We have compared GC- and AT-rich isochores of yeast with respect to chromatin conformation histone modification status and transcription. Using 3C analysis we show that along chromosome III GC-rich isochores have a chromatin structure that is characterized by lower chromatin interaction frequencies compared to AT-rich isochores which may point to a more extended chromatin conformation. In addition we find that throughout the genome GC-rich and AT-rich genes display distinct levels of histone modifications. Interestingly elimination of the histone deacetylase Rpd3p differentially affects conformation of GC- and AT-rich domains. Further deletion of RPD3 activates expression of GC-rich genes more strongly