期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1990
卷号：87
期号：24
页码：9761-9765
DOI：10.1073/pnas.87.24.9761
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：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.
