GSE104312
RNA transcription profile of different yeast mutants under glucose starvation (0.05% glucose) and comparison of transcriptome of WT and H3D_H3H
Modifications on histone tails largely affect chromatin associated processes. Previous studies have shown the existence of asymmetrically modified nucleosomes in promoters in multiple cell types. However, whether modifications on both sister histones contribute equally to chromatin dynamics remains elusive. Here we devised a bivalent nucleosome system which allows for the constitutive assembly of asymmetrically modified sister histone H3 in nucleosomes in vivo. We found that the H3K36 methylation on either of sister histones sensitize chromatin structure in gene coding region, while the H3K79 methylation on both sister histone H3s are indispensable for maintaining silent chromatin near telomeres. Additionally, the H3K4 methylation on sister histones plays an equivalent role in suppressing the recruitment of Gal4 activator at GAL1 promoter and GAL1 transcription. Moreover, under starvation stress the expression of a significant proportion of genes in the whole genome is affected by the lack of the H3K4 methylation on one tail of the sister histones, indicating that both sister histones function in fine-tuning transcription through their modifications. We conclude that modifications on sister histones either cooperatively or independently respond to the change of an environmental cue to regulate chromatin structure and function. This work provides a unique experimental strategy to investigate the cross talk between sister histones, and for the first time elaborate their contributions to chromatin in vivo. Overall design: Examination of the profile of RNA transcription of different mutants under glucose starvation (0.05% glucose) and comparison of transcriptome of WT and H3D_H3H