The adaptor protein SLP-76 regulates HIV-1 release and cell-to-cell transmission in T cells

J Immunol. 2012 Mar 15;188(6):2769-77. doi: 10.4049/jimmunol.1102106. Epub 2012 Feb 8.

Abstract

HIV-1 infection in T cells is regulated by TCR activation. However, the cellular proteins of the TCR pathway that regulate HIV-1 infection are poorly characterized. In this study, in HIV-1 infection, we observed a significant reduction of HIV-1 virus production in Src homology 2 domain-containing leukocyte protein of 76 kDa (SLP-76)-deficient Jurkat T cells compared with wild-type and SLP-76-reconstituted Jurkat T cells. We further confirmed the role of SLP-76 in HIV-1 infection by small interfering RNA-mediated knockdown in MT4 cells and PBMCs. Structural-functional analysis revealed that the N-terminal domain of SLP-76 was important for regulating HIV-1 infection. Further mechanistic studies revealed that lack of SLP-76 impaired virus release, but did not affect viral entry, integration, and transcription. We also showed that SLP-76 plays a critical role in cell-to-cell transmission of HIV-1. Signaling studies revealed that SLP-76 associated with viral negative regulatory factor protein and multiple signaling molecules during HIV-1 infection. Furthermore, SLP-76 facilitated the association of negative regulatory factor and F-actin, suggesting that SLP-76 mediates the formation of a signaling complex that may regulate viral release via cytoskeletal changes. Taken together, our studies demonstrate a novel role for the adaptor molecule SLP-76 in regulating HIV-1 infection in T cells with the potential to develop innovative strategies against HIV-1.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / immunology
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Blotting, Western
  • Cell Separation
  • Flow Cytometry
  • HIV-1 / immunology
  • HIV-1 / metabolism*
  • HIV-1 / pathogenicity*
  • Humans
  • Jurkat Cells
  • Microscopy, Confocal
  • Phosphoproteins / immunology
  • Phosphoproteins / metabolism*
  • RNA, Small Interfering
  • T-Lymphocytes / metabolism
  • T-Lymphocytes / virology*
  • Transfection

Substances

  • Adaptor Proteins, Signal Transducing
  • Phosphoproteins
  • RNA, Small Interfering
  • SLP-76 signal Transducing adaptor proteins