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Dynamic regulation of transcription factors by nucleosome remodeling.

ABSTRACT: The chromatin landscape and promoter architecture are dominated by the interplay of nucleosome and transcription factor (TF) binding to crucial DNA sequence elements. However, it remains unclear whether nucleosomes mobilized by chromatin remodelers can influence TFs that are already present on the DNA template. In this study, we investigated the interplay between nucleosome remodeling, by either yeast ISW1a or SWI/SNF, and a bound TF. We found that a TF serves as a major barrier to ISW1a remodeling, and acts as a boundary for nucleosome repositioning. In contrast, SWI/SNF was able to slide a nucleosome past a TF, with concurrent eviction of the TF from the DNA, and the TF did not significantly impact the nucleosome positioning. Our results provide direct evidence for a novel mechanism for both nucleosome positioning regulation by bound TFs and TF regulation via dynamic repositioning of nucleosomes.

SUBMITTER: Li M

PROVIDER: S-EPMC4456607 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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Dynamic regulation of transcription factors by nucleosome remodeling.

Li Ming M Hada Arjan A Sen Payel P Olufemi Lola L Hall Michael A MA Smith Benjamin Y BY Forth Scott S McKnight Jeffrey N JN Patel Ashok A Bowman Gregory D GD Bartholomew Blaine B Wang Michelle D MD

eLife 20150605

The chromatin landscape and promoter architecture are dominated by the interplay of nucleosome and transcription factor (TF) binding to crucial DNA sequence elements. However, it remains unclear whether nucleosomes mobilized by chromatin remodelers can influence TFs that are already present on the DNA template. In this study, we investigated the interplay between nucleosome remodeling, by either yeast ISW1a or SWI/SNF, and a bound TF. We found that a TF serves as a major barrier to ISW1a remodel ...[more]

PMID: 26047462

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