Previous Article | Next Article ![]()
J. Virol., 01 1997, 378-382, Vol 71, No. 1
T Lund, MM Medveczky and PG Medveczky
Herpesvirus saimiri (HVS) is a T-cell-specific transforming and oncogenic
virus. A protein encoded by HVS known as Tip-484 (for tyrosine kinase
interacting protein from HVS strain 484) is required for this
transformation. Tip-484 binds specifically to the nonreceptor protein
tyrosine kinase p56lck. By transfecting Tip-484 into T cells, we now show
that this interaction leads to a several hundred-fold increase in the
kinase activity of p56lck. Tip-484 is part of a protein complex which is
dependent on the presence of p56lck and is phosphorylated. We also show
that two of the complexed proteins represent two phosphorylated forms of
Tip-484. Furthermore, the p56lck kinase activity in HVS-infected human
peripheral blood T lymphocytes was at least ninefold higher than that in
noninfected control cells and significantly decreased in cells infected
with a Tip-484 deletion mutant virus. Finally, we report that Tip-484 is
required for oncogenesis in rabbits by the survival of rabbits inoculated
with Tip- 484 deletion mutant HVS. The data demonstrate dramatic
stimulation of the signaling pathway of p56lck. This effect can contribute
to the molecular mechanisms that lead to sustained autocrine secretion of
growth factors, permanent T-cell growth, and ultimately lymphocytic tumor
formation.
Copyright © 1997, American Society for Microbiology
Herpesvirus saimiri Tip-484 membrane protein markedly increases p56lck activity in T cells
Department of Microbiology and Immunology, University of South Florida, Tampa 33612-4799, 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»