충북대학교 종양연구소에서 다음과 같이 초청세미나를 개최하오니 많은 참여 부탁드립니다.
- 다 음 -
1. 연 자 : 이 철 구 박사
( University of North Carolina-Chapel Hill )
2. 일 시 : 2004 년 8 월 2 일 (월) 오전 11시
3. 연 제 : Genome-Wide Nucleosome Disruption at Active Regulatory Region
4. 장 소 : 종양연구소 106호 (세미나실)
5. 발표 내용 : The identification of nuclease-hypersensitive sites in an active globin gene and in the 5' regions of fruit fly heat shock genes first suggested that chromatin changes accompany gene regulation in vivo.
Here we present evidence that the basic repeating units of eukaryotic chromatin, nucleosomes, are depleted from active regulatory elements throughout the Saccharomyces cerevisiae genome in vivo. We found that during rapid mitotic growth, the level of nucleosome occupancy is
inversely proportional to the transcriptional initiation rate at the promoter. We also observed a partial loss of histone H3 and H4 tetramers from the coding regions of the most heavily transcribed genes. Alterations in the global transcriptional program caused by heat shock or a change in carbon source resulted in an increased nucleosome occupancy at repressed promoters, and a decreased nucleosome occupancy at promoters that became active. Nuclease-hypersensitive sites occur in species from yeast to humans and result from chromatin perturbation.
Given the conservation of sequence and function among components of both chromatin and the transcriptional machinery, nucleosome depletion at promoters may be a fundamental feature of eukaryotic transcriptional regulation.