Simian virus 40 large T antigen binds a novel Bcl-2 homology domain 3- containing proapoptosis protein in the cytoplasm

Shih Chong Tsai, Kishore B.S. Pasumarthi, Laura Pajak, Michael Franklin, Brian Patton, He Wang, William J. Henzel, John T. Stults, Loren J. Field

Research output: Contribution to journalArticle

59 Scopus citations

Abstract

A 193-kDa SV40 large T antigen (T-Ag)-binding protein, designated p193, was identified and cloned. Inspection of the deduced amino acid sequence revealed the presence of a short motif similar to the Bcl-2 homology (BH) domain 3, suggesting that p193 may be a member of a family of apoptosis promoting proteins containing only BH3 motifs. In support of this, p193 expression promoted apoptosis in NIH-3T3 cells. Deletion of the BH3 motif abolished p193 apoptosis activity, p193-induced apoptosis was antagonized by co-expression of Bcl-X(L). Immune cytologic analysis indicated that p193 is localized to the cytoplasm of transfected cells, p193-induced apoptosis was also antagonized by co-expression of T-Ag, which resulted in the cytoplasmic localization of both proteins. The p193 binding site was mapped to an N- terminal region of T-Ag previously implicated in transforming activity. These results suggest that T-Ag possesses an antiapoptosis activity, independent of p53 sequestration, which is actuated by T-Ag/p193 binding in the cytoplasm.

Original languageEnglish (US)
Pages (from-to)3239-3246
Number of pages8
JournalJournal of Biological Chemistry
Volume275
Issue number5
DOIs
StatePublished - Feb 4 2000

    Fingerprint

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Cite this

Tsai, S. C., Pasumarthi, K. B. S., Pajak, L., Franklin, M., Patton, B., Wang, H., Henzel, W. J., Stults, J. T., & Field, L. J. (2000). Simian virus 40 large T antigen binds a novel Bcl-2 homology domain 3- containing proapoptosis protein in the cytoplasm. Journal of Biological Chemistry, 275(5), 3239-3246. https://doi.org/10.1074/jbc.275.5.3239