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The nucleosome DNA entry-exit site is important for transcription termination and prevention of pervasive transcription

ABSTRACT: Compared to the initiation and elongation stages of transcription, the role of chromatin in transcription termination is poorly understood. Through a yeast genetic screen, we identified histone H3 and H4 substitutions that cause transcription to read through the terminator of a small noncoding gene. The substitutions map to the nucleosome DNA entry-exit site, a region that controls nucleosome stability and certain histone modifications. Genome-wide studies on the strongest mutants revealed evidence of transcription read-through of noncoding and coding genes and reduced nucleosome occupancy. Replacement of the native sequence downstream of a gene with a “superbinder” sequence that increases nucleosome occupancy in vivo increased termination efficiency and suppressed the effect of a DNA entry-exit site substitution at this locus. Our results highlight the importance of the DNA entry-exit site in maintaining the integrity of the transcriptome and suggest that nucleosomes can facilitate termination by serving as a barrier to RNA polymerase.

ORGANISM(S): Saccharomyces cerevisiae

PROVIDER: GSE147389 | GEO | 2020/08/10

REPOSITORIES: GEO

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The nucleosome DNA entry-exit site is important for transcription termination and prevention of pervasive transcription

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