Send to

Choose Destination
EMBO J. 1994 Jan 1;13(1):90-9.

Genetic and immunochemical evidence for CD4-dependent association of p56lck with the alpha beta T-cell receptor (TCR): regulation of TCR-induced activation.

Author information

Centro de Investigaciones Biológicas, C.S.I.C., Madrid, Spain.


Recent observations suggest that the tyrosine kinase p56lck is involved in the transduction of transmembrane signals through the antigen specific T cell receptor (TCR) in CD4+ T cells. By means of in vitro kinase assays, we have found that p56lck coprecipitated with the TCR from lysates of a murine CD4+ T cell line in the absence of TCR-mediated stimuli. Analysis of CD4- mutants and CD4-transfected cells shows that p56lck-TCR association occurred only when CD4 was present. The functional importance of CD4:p56lck-TCR association was demonstrated by low activating potential of rare clonotypic antibodies which did not coprecipitate CD4:p56lck, as well as by total or partial loss of anti-TCR or antigen induced stimulation in CD4- cells, which could be recovered by CD4 transfection. Complementation assays using different anti-TCR antibodies suggest that cross linking of TCR-p56lck:CD4 plus structural changes in the complex are needed for efficient transduction of activating signals through the TCR in these cells.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center