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A chromatin-remodeling protein is a component of fission yeast mediator.

ABSTRACT: The multiprotein Mediator complex is an important regulator of RNA polymerase II-dependent genes in eukaryotic cells. In contrast to the situation in many other eukaryotes, the conserved Med15 protein is not a stable component of Mediator isolated from fission yeast. We here demonstrate that Med15 exists in a protein complex together with Hrp1, a CHD1 ATP-dependent chromatin-remodeling protein. The Med15-Hrp1 subcomplex is not a component of the core Mediator complex but can interact with the L-Mediator conformation. Deletion of med15(+) and hrp1(+) causes very similar effects on global steady-state levels of mRNA, and genome-wide analyses demonstrate that Med15 associates with a distinct subset of Hrp1-bound gene promoters. Our findings therefore indicate that Mediator may directly influence histone density at regulated promoters.

SUBMITTER: Khorosjutina O

PROVIDER: S-EPMC2943280 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature

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A chromatin-remodeling protein is a component of fission yeast mediator.

Khorosjutina Olga O Wanrooij Paulina H PH Walfridsson Julian J Szilagyi Zsolt Z Zhu Xuefeng X Baraznenok Vera V Ekwall Karl K Gustafsson Claes M CM

The Journal of biological chemistry 20100709 39

The multiprotein Mediator complex is an important regulator of RNA polymerase II-dependent genes in eukaryotic cells. In contrast to the situation in many other eukaryotes, the conserved Med15 protein is not a stable component of Mediator isolated from fission yeast. We here demonstrate that Med15 exists in a protein complex together with Hrp1, a CHD1 ATP-dependent chromatin-remodeling protein. The Med15-Hrp1 subcomplex is not a component of the core Mediator complex but can interact with the L- ...[more]

PMID: 20622008

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