In vivo disruption of T cell development by expression of a dominant-negative polypeptide designed to abolish the SLP-76/Gads interaction.
Multi-molecular complexes nucleated by adaptor proteins play a central role in signal transduction. In T cells, one central axis consists of the assembly of several signaling proteins linked together by the adaptors linker of activated T cells (LAT), Src homology 2 domain-containing leukocyte-specific phosphoprotein of 76 kDa (SLP-76), and Grb2-related adaptor downstream of Shc (Gads). Each of these adaptors has been shown to be important for normal T cell development, and their proper sub-cellular localization is critical for optimal function in cell lines. We previously demonstrated in Jurkat T cells and a rat basophilic leukemic cell line that expression of a 50-amino acid polypeptide identical to the site on SLP-76 that binds to Gads blocks proper localization of SLP-76 and SLP-76-dependent signaling events. Here we extend these studies to investigate the ability of this polypeptide to inhibit TCR-induced integrin activity in Jurkat cells and to inhibit in vivo thymocyte development and primary T cell function. These data provide evidence for the in vivo function of a dominant-negative peptide based upon the biology of SLP-76 action and suggest the possibility of therapeutic potential of targeting the SLP-76/Gads interaction.
Jordan
Martha S
MS
Department of Cancer Biology, Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA 19104, USA.
Maltzman
Jonathan S
JS
Kliche
Stefanie
S
Shabason
Jacob
J
Smith
Jennifer E
JE
Obstfeld
Amrom
A
Schraven
Burkhart
B
Koretzky
Gary A
GA
D048868:Adaptor Proteins, Signal Transducing / Q000037:antagonists & inhibitors / Q000172:deficiency / Q000378:metabolism*; D000818:Animals; D002448:Cell Adhesion / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000276:immunology; D002478:Cells, Cultured; D054377:Chemokine CXCL12 / Q000502:physiology; D006131:Growth Inhibitors / Q000138:chemical synthesis / Q000235:genetics / Q000502:physiology*; D006801:Humans; D016023:Integrins / Q000037:antagonists & inhibitors / Q000502:physiology; D019169:Jurkat Cells; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D010446:Peptide Fragments / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology; D010455:Peptides / Q000138:chemical synthesis* / Q000235:genetics* / Q000502:physiology; D010750:Phosphoproteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011485:Protein Binding / Q000276:immunology; D051381:Rats; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology / Q000378:metabolism*