Structural "Snap-shots" of the Initiation of SV40 Replication
Gretchen Meinke and Peter A. Bullock
from: Small DNA Tumour Viruses (Edited by: Kevin Gaston). Caister Academic Press, U.K. (2012)
The initiation of DNA replication, which is one of the fundamental processes in eukaryotic cells, is not understood at the molecular level. Therefore, several laboratories are attempting to understand this process using the Simian Virus 40 replication system; a relatively simple and well-characterized model for studies of eukaryotic DNA replication. The replication initiator encoded by Simian Virus 40 is termed T-antigen. Molecular structures have been obtained for the three major domains of T-antigen. Moreover, several structures are now available of the central "origin binding domain" in complex with various DNA substrates. Collectively these structures have provided a series of "snap-shots" of the initiation process. They have also significantly improved our understanding of such diverse processes as site specific binding during origin recognition, melting of origin sequences, oligomerization of T-antigen (to form hexamers and double hexamers) and the molecular basis for helicase activity read more ...