Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.7.6 (RNA polymerase)
 34,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Numerous transcription accessory proteins cause alterations in chromatin structure that promote the progression of RNA polymerase II (Pol II) along open reading frames (ORFs). The Saccharomyces cerevisiae Paf1 complex colocalizes with actively transcribing Pol II and orchestrates modifications to the chromatin template during transcription elongation. To better understand the function of the Rtf1 subunit of the Paf1 complex, we created a series of sequential deletions along the length of the protein. Genetic and biochemical assays were performed on these mutants to identify residues required for the various activities of Rtf1. Our results establish that discrete nonoverlapping segments of Rtf1 are necessary for interaction with the ATP-dependent chromatin-remodeling protein Chd1, promoting covalent modification of histones H2B and H3, recruitment to active ORFs, and association with other Paf1 complex subunits. We observed transcription-related defects when regions of Rtf1 that mediate histone modification or association with active genes were deleted, but disruption of the physical association between Rtf1 and other Paf1 complex subunits caused only subtle mutant phenotypes. Together, our results indicate that Rtf1 influences transcription and chromatin structure through several independent functional domains and that Rtf1 may function independently of its association with other members of the Paf1 complex.
 ...
PMID:Rtf1 is a multifunctional component of the Paf1 complex that regulates gene expression by directing cotranscriptional histone modification. 1757 14

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.
 ...
PMID:A chromatin-remodeling protein is a component of fission yeast mediator. 2062 8