Molecular interaction between the Fyn-associated protein SKAP55 and the SLP-76-associated phosphoprotein SLAP-130.
It has previously been reported that in resting T-lymphocytes the protein tyrosine kinase p59 constitutively co-precipitates with four phosphoproteins of 43, 55, 85, and 120 kDa, respectively. We have recently cloned the 55-kDa protein that was termed Src kinase-associated phosphoprotein of 55 kDa (SKAP55). Here we demonstrate that the recently characterized SH2-domain-containing leukocyte protein 76-associated phosphoprotein of 130 kDa (SLAP-130) is one of the components of the Fyn complex and that it also co-precipitates with SKAP55 in human T-cells. We establish that SKAP55 and SLAP-130 associate with each other when both molecules are co-expressed in COS cells. By co-transfection of truncated mutants of SKAP55 and SLAP-130 as well as by using the two-hybrid selection system, we further demonstrate that the association between SLAP-130 and SKAP55 is direct and involves the Src homology 3 domain of SKAP55 and the proline-rich sequence of SLAP-130.
Marie-Cardine
A
A
Ruprecht-Karls University of Heidelberg, Institute for Immunology, 69120 Heidelberg, Germany.
Hendricks-Taylor
L R
LR
Boerth
N J
NJ
Zhao
H
H
Schraven
B
B
Koretzky
G A
GA
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D019556:COS Cells; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D006801:Humans; D019169:Jurkat Cells; D009154:Mutation / Q000235:genetics; D009842:Oligopeptides; D010455:Peptides / Q000235:genetics / Q000276:immunology; D010750:Phosphoproteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000737:chemistry*; D051076:Proto-Oncogene Proteins c-fyn; D015398:Signal Transduction / Q000502:physiology; D014162:Transfection / Q000235:genetics; D018909:src Homology Domains / Q000235:genetics
D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; C106957:FYB1 protein, human; D009842:Oligopeptides; D010455:Peptides; D010750:Phosphoproteins; D011518:Proto-Oncogene Proteins; C108336:SKAP1 protein, human; C085706:FLAG peptide; C494957:FYN protein, human; D051076:Proto-Oncogene Proteins c-fyn