A yeast two-hybrid study of human p97/Gab2 interactions with its SH2 domain-containing binding partners.
p97/Gab2 is a recently characterized member of a large family of scaffold proteins that play essential roles in signal transduction. Gab2 becomes tyrosine-phosphorylated in response to a variety of growth factors and forms multimolecular complexes with SH2 domain-containing signaling molecules such as the p85-regulatory subunit of the phosphoinositide-3-kinase (p85-PI3K), the tyrosine phosphatase SHP-2 and the adapter protein CrkL. To characterize the interactions between Gab2 and its SH2-containing binding partners, we designed a modified yeast two-hybrid system in which the Lyn tyrosine kinase is expressed in a regulated manner in yeast. Using this assay, we demonstrated that p97/Gab2 specifically interacts with the SH2 domains of PI3K, SHP-2 and CrkL. Interaction with p85-PI3K is mediated by tyrosine residues Y452, Y476 and Y584 of Gab2, while interaction with SHP-2 depends exclusively on tyrosine Y614. CrkL interaction is mediated by its SH2 domain recognizing Y266 and Y293, despite the latter being in a non-consensus (YTFK) environment.
Crouin
C
C
Inserm Unit 461, Faculté de Pharmacie Paris-XI, Châtenay-Malabry, france.
Arnaud
M
M
Gesbert
F
F
Camonis
J
J
Bertoglio
J
J
D048868:Adaptor Proteins, Signal Transducing; D002460:Cell Line; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000737:chemistry / Q000378:metabolism; D010750:Phosphoproteins / Q000737:chemistry* / Q000378:metabolism*; D010766:Phosphorylation; D019000:Phosphotyrosine / Q000378:metabolism; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases / Q000737:chemistry / Q000378:metabolism; D054593:SH2 Domain-Containing Protein Tyrosine Phosphatases; D012441:Saccharomyces cerevisiae / Q000235:genetics; D020798:Two-Hybrid System Techniques; D018909:src Homology Domains
D048868:Adaptor Proteins, Signal Transducing; D047908:Intracellular Signaling Peptides and Proteins; D009687:Nuclear Proteins; D010455:Peptides; D019869:Phosphatidylinositol 3-Kinases; D010750:Phosphoproteins; D019000:Phosphotyrosine; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6; D017027:Protein Tyrosine Phosphatases; D054593:SH2 Domain-Containing Protein Tyrosine Phosphatases; C082869:CRKL protein; C490895:GAB2 protein, human; C516724:PTPN11 protein, human; C509249:PTPN6 protein, human