
E2F from adenovirus-infected cells binds cooperatively to DNA containing two properly oriented and spaced recognition sites.
Author(s) -
Simon Hardy,
Thomas Shenk
Publication year - 1989
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.9.10.4495
Subject(s) - e2f , biology , cooperativity , dna , binding site , cooperative binding , adenoviridae , microbiology and biotechnology , recognition sequence , cell , cell cycle , gene , recombinant dna , genetics , restriction enzyme
E2F is a sequence-specific DNA-binding factor which binds to sites that occur in pairs upstream of the adenovirus E1A and E2 early transcriptional start sites. Substantial quantities of E2F activity were found in uninfected-cell extracts, and there was a modest increase in E2F activity during an adenovirus type 5 (Ad5) infection. In uninfected cells, E2F was found to exist in multiple forms that could be separated chromatographically. Extracts prepared at 24 h after Ad5 infection contained a new form of E2F. This infection-specific form may have been a modified version of one of the forms present in uninfected cells. The infection-specific E2F was shown to bind cooperatively to a pair of E2F sites found upstream of the Ad2 early region 2 mRNA cap site. This binding was sensitive to the spacing between the sites and their relative orientation. In contrast, E2F binding in uninfected-cell extracts was unaffected by changes in orientation and spacing, consistent with very low cooperativity or independent binding.