Recent studies from the investigator's laboratory have identified a cellular nuclear protein, Sam68, which specifically interacts with RRE and can substitute for as well as synergize with Rev in RRE mediated gene expression and virus replication. The major goals of this proposal are to functionally characterize Sam68 protein in RRE-mediated transactivation and determine the relevance of Sam68 in HIV replication.
The specific aims are: 1) to functionally characterize the interactions of Sam68 with Rev and/or RRE RNA in RRE-mediated gene expression using truncated and site-directed mutants to map domains of Sam68 and its binding sites on RRE as well as Rev that are functionally involved in RRE-mediated gene expression and virus replication; 2) to investigate the functional relevance of Sam68 in HIV replication by inactivation of Sam68 genes using ribozymes, antisense, and anti- Sam68 antibodies.
This Aim will also generate an in vitro model for the enhancement of HIV replication in NIH 3T3 cells by Sam68; 3) to assess the long-term protection of primary cells expressing transdominant mutants of Sam68 from HIV infection by transducing T lymphocytes and primary cells with a retroviral vector encoding transdominant negative mutants of Sam68 and assessing long-term protection of these cells from HIV-1 infection. The effect of Sam68 on HIV mutants that are resistant to Rev M10 will also be assessed. These studies may allow the development of novel anti-viral agents.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
1R01AI046240-01A2
Application #
6214331
Study Section
Special Emphasis Panel (ZRG1-AARR-1 (01))
Program Officer
Plaeger, Susan F
Project Start
2000-07-01
Project End
2000-09-29
Budget Start
2000-07-01
Budget End
2000-09-29
Support Year
1
Fiscal Year
2000
Total Cost
$29,528
Indirect Cost
Name
University of California San Diego
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
077758407
City
La Jolla
State
CA
Country
United States
Zip Code
92093
Modem, Suhasini; Chinnakannu, Kannagi; Bai, Uma et al. (2011) Hsp22 (HspB8/H11) knockdown induces Sam68 expression and stimulates proliferation of glioblastoma cells. J Cell Physiol 226:2747-51
Modem, Suhasini; Reddy, Thipparthi R (2008) An anti-apoptotic protein, Hax-1, inhibits the HIV-1 rev function by altering its sub-cellular localization. J Cell Physiol 214:14-9
Badri, Kameswara R; Modem, Suhasini; Gerard, Herve C et al. (2006) Regulation of Sam68 activity by small heat shock protein 22. J Cell Biochem 99:1353-62
Modem, Suhasini; Badri, Kameswara R; Holland, Thomas C et al. (2005) Sam68 is absolutely required for Rev function and HIV-1 production. Nucleic Acids Res 33:873-9
Singh, Kameshwar P; Gerard, Herve C; Hudson, Alan P et al. (2005) Retroviral Foxp3 gene transfer ameliorates liver granuloma pathology in Schistosoma mansoni infected mice. Immunology 114:410-7
Yang, Jian-Ping; Reddy, Thipparthi R; Truong, Ky T et al. (2002) Functional interaction of Sam68 and heterogeneous nuclear ribonucleoprotein K. Oncogene 21:7187-94
Xu, W; Zhang, Y; Yeh, L Y et al. (2002) One-step, highly efficient site-directed mutagenesis by toxic protein selection. Biotechniques 32:1266-8, 1270
Reddy, T Raghavendar; Suhasini, Modem; Xu, Weidong et al. (2002) A role for KH domain proteins (Sam68-like mammalian proteins and quaking proteins) in the post-transcriptional regulation of HIV replication. J Biol Chem 277:5778-84
Reddy, T R; Xu, W D; Wong-Staal, F (2000) General effect of Sam68 on Rev/Rex regulated expression of complex retroviruses. Oncogene 19:4071-4