Previous Article | Next Article ![]()
Mol. Cell. Biol., 10 1997, 6139-6146, Vol 17, No. 10
AC Wilson, RN Freiman, H Goto, T Nishimoto and W Herr
The herpes simplex virus (HSV) regulatory protein VP16 activates HSV
immediate-early gene transcription through formation of a multiprotein- DNA
complex on viral promoters that includes the preexisting nuclear proteins
HCF and Oct-1. The HCF protein is a complex of amino- and carboxy-terminal
polypeptides derived from a large (approximately 2,000- amino-acid)
precursor by proteolytic processing. Here we show that a 361-residue
amino-terminal region of HCF is sufficient to bind VP16, stabilize
VP16-induced complex assembly with Oct-1 and DNA, and activate
transcription in vivo. This VP16 interaction region contains six kelch-like
repeats, a degenerate repeat motif that is likely to fold as a distinctive
beta-propeller structure. The third HCF kelch repeat includes a proline
residue (P134) that is mutated to serine in hamster tsBN67 cells, resulting
in a temperature-sensitive defect in cell proliferation. This missense
mutation also prevents direct association between HCF and VP16, suggesting
that VP16 mimics a cellular factor required for cell proliferation. Rescue
of the tsBN67 cell proliferation defect by HCF, however, requires both the
VP16 interaction domain and an adjacent basic region, indicating that HCF
utilizes multiple regions to promote cell cycle progression.
Copyright © 1997, American Society for Microbiology
VP16 targets an amino-terminal domain of HCF involved in cell cycle progression
Cold Spring Harbor Laboratory, New York 11724, USA.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»