Recombinant 43-kDa USF Binds to DNA and Activates Transcription in a Manner Indistinguishable from That of Natural 43/44-kDa USF
Year: 1991
Type: article
Abstract: USF is a cellular factor involved in the transcriptional regulation of several cellular and viral promoters. Purified USF from HeLa cells (HeLa USF) consists of 43- and 44-kDa polypeptides which show independent binding to a specific DNA element. A cDNA encoding the 43-kDa species has been previously cloned. We show here that the purified form of bacterially expressed 43-kDa USF (i) exists in solution as a dimer whose formation is greatly favored under reducing conditions, (ii) binds to its cognate DNA sequence in a manner indistinguishable from that of HeLa USF, and (iii) is as efficient as HeLa USF in stimulating transcription from target promoters in a reconstituted cell-free system. Additional data indicate that the 44-kDa component of HeLa USF is immunologically unrelated to the 43-kDa polypeptide but is associated with it in HeLa cell extracts. These results suggest that the 43-kDa component possesses an intrinsic DNA binding and transcriptional activation potential and that the 44-kDa USF component of the natural USF complex may have some regulatory role.
Source: Molecular and Cellular Biology
Authors: P Pognonec, R G Roeder
Institution: Rockefeller University
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W1851224896