Abstract
Chromatin structure and protein-protein interactions play an important role in eukaryotic gene function. Nucleosomal rearrangement at the simian virus 40 (SV40) regulatory region occurs at the late stages of the viral life cycle preceding viral assembly. The SV40 capsid proteins are required for this nucleosomal rearrangement suggesting that they participate in turning-off the viral promoters. In aiming to elucidate the role of the capsid proteins in gene regulation, we studied the interaction between VP3, an internal capsid protein, and the cellular transcription factor Sp1, a major regulator of both the early and late viral promoters. Our results showed that VP3 repressed transcription from the viral early promoter in vitro. We found significant cooperativity between Sp1 and VP3 in specific DNA-binding to the Sp1 binding site. In addition, protein-protein interactions between VP3 and Sp1 in the absence of DNA were observed. These findings have led us to conclude that the novel host-viral Sp1-VP3 complex down regulates viral transcription and further suggest that Sp1 participates in recruiting VP3 to the SV40 minichromosome in SV40 assembly.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.