title: Characterization of the CIN85 adaptor protein and identification of components involved in CIN85 complexes.
abstract: CIN85 is an 85-kDa adaptor protein whose functions in signaling pathways are presently unknown. Using the yeast two-hybrid screen, the B cell linker protein (BLNK) was identified as a binding partner of CIN85. Coimmunoprecipitation experiments using mammalian cells revealed that CIN85 directly bound to BLNK through its SH3 domains. Immunostaining analysis showed that CIN85 and BLNK were colocalized in the cytoplasm. These results indicate a potential role of CIN85 in the B cell receptor-mediated signaling pathway. It was also found that Crk-I, Crk-II, p130(Cas), p85-PI3K, Grb2, and Sos1 were components of CIN85 complexes. CIN85 interacted with itself through its coiled-coil region, resulting in formation of a tetramer. Both the coiled-coil region and SH3 domains of CIN85 were responsible for its subcellular localization. Our data suggest that CIN85 may serve for regulation of various signaling events through formation of its diverse complexes.
authors.affiliation: Hematology Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: S
authors.initials: S
authors.lastname: Watanabe
authors.forename: H
authors.initials: H
authors.lastname: Take
authors.forename: K
authors.initials: K
authors.lastname: Takeda
authors.forename: Z X
authors.initials: ZX
authors.lastname: Yu
authors.forename: N
authors.initials: N
authors.lastname: Iwata
authors.forename: S
authors.initials: S
authors.lastname: Kajigaya
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D001665:Binding Sites; D019556:COS Cells; D002352:Carrier Proteins / Q000737:chemistry*; D002460:Cell Line; D050719:Crk-Associated Substrate Protein; D003432:Cross-Linking Reagents / Q000494:pharmacology; D003593:Cytoplasm / Q000378:metabolism; D051380:GRB2 Adaptor Protein; D015723:Gene Library; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D008856:Microscopy, Fluorescence; D017830:Octoxynol / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D011485:Protein Binding; D011494:Protein Kinases / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000378:metabolism; D011518:Proto-Oncogene Proteins; D050737:Proto-Oncogene Proteins c-crk; D050717:Retinoblastoma-Like Protein p130; D020837:SOS1 Protein / Q000378:metabolism; D015398:Signal Transduction; D014162:Transfection; D020798:Two-Hybrid System Techniques; D018909:src Homology Domains
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C493841:BCAR1 protein, human; D002352:Carrier Proteins; D050719:Crk-Associated Substrate Protein; D003432:Cross-Linking Reagents; D051380:GRB2 Adaptor Protein; C495948:GRB2 protein, human; D010750:Phosphoproteins; D011506:Proteins; D011518:Proto-Oncogene Proteins; D050737:Proto-Oncogene Proteins c-crk; D050717:Retinoblastoma-Like Protein p130; C433810:SH3KBP1 protein, human; D020837:SOS1 Protein; D017830:Octoxynol; D011494:Protein Kinases; D019869:Phosphatidylinositol 3-Kinases