Open AccessIn vitro regulation of a SIN3-dependent DNA-binding activity by stimulatory and inhibitory factors.
Author(s) -
Huaming Wang,
David J. Stillman
Publication year - 1990
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.87.24.9761
Subject(s) - repressor , dna , biochemistry , yeast , in vitro , microbiology and biotechnology , binding site , gene , biology , plasma protein binding , dna binding protein , chemistry , transcription factor
The yeast SIN3 gene (also known as SDII, is a known negative regulator of the yeast HO gene. A DNA-binding activity, called SDP1, which binds to the HO promoter, is absent in extracts prepared from sin3 mutants and has been proposed to function as a repressor. We show that SIN3 does not encode SDP1 and that SDP1 DNA-binding activity is modulated in vitro by two factors, an inhibitory factor, I-SDP1, and a stimulatory factor, S-SDP1. I-SDP1 acts as an in vitro inhibitor of the SDP1 DNA-binding activity. Restoration of the DNA-binding activity is achieved by inclusion of a stimulatory factor, S-SDP1, which copurifies with the SIN3 protein. SDP1 DNA-binding activity was restored by treating a protein fraction containing SDP1 and I-SDP1 with the dissociating agent formamide.