期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2003
卷号:100
期号:11
页码:6364-6369
DOI:10.1073/pnas.1131966100
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Epigenetic modifications of chromatin serve an important role in regulating the expression and accessibility of genomic DNA. We report here a genomewide approach for fractionating yeast chromatin into two functionally distinct parts, one containing RNA polymerase II transcribed sequences, and the other comprising noncoding sequences and genes transcribed by RNA polymerases I and III. Noncoding regions could be further fractionated into promoters and segments lacking promoters. The observed separations were apparently based on differential crosslinking efficiency of chromatin in different genomic regions. The results reveal a genomewide molecular mechanism for marking promoters and genomic regions that have a license to be transcribed by RNA polymerase II, a previously unrecognized level of genomic complexity that may exist in all eukaryotes. Our approach has broad potential use as a tool for genome annotation and for the characterization of global changes in chromatin structure that accompany different genetic, environmental, and disease states.