Hic-5, a paxillin homologue, binds to the protein-tyrosine phosphatase PEST (PTP-PEST) through its LIM 3 domain.
The Hic-5 protein is encoded by a transforming growth factor-beta1- and hydrogen peroxide-inducible gene, hic-5, and has striking similarity to paxillin, especially in their C-terminal LIM domains. Like paxillin, Hic-5 is localized in focal adhesion plaques in association with focal adhesion kinase in cultured fibroblasts. We carried out yeast two-hybrid screening to identify cellular factors that form a complex with Hic-5 using its LIM domains as a bait, and we identified a cytoplasmic tyrosine phosphatase (PTP-PEST) as one of the partners of Hic-5. These two proteins are associated in mammalian cells. From in vitro binding experiments using deletion and point mutations, it was demonstrated that the essential domain in Hic-5 for the binding was LIM 3. As for PTP-PEST, one of the five proline-rich sequences found on PTP-PEST, Pro-2, was identified as the binding site for Hic-5 in in vitro binding assays. Paxillin also binds to the Pro-2 domain of PTP-PEST. In conclusion, Hic-5 may participate in the regulation of signaling cascade through its interaction with distinct tyrosine kinases and phosphatases.
Nishiya
N
N
Department of Microbiology, Showa University School of Pharmaceutical Sciences, Hatanodai 1-5-8, Shinagawa-ku, Tokyo, Japan.
Iwabuchi
Y
Y
Shibanuma
M
M
Côté
J F
JF
Tremblay
M L
ML
Nose
K
K
D000818:Animals; D001665:Binding Sites; D002478:Cells, Cultured; D003598:Cytoskeletal Proteins / Q000235:genetics / Q000378:metabolism*; D018076:DNA, Complementary / Q000737:chemistry / Q000302:isolation & purification; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D018398:Homeodomain Proteins / Q000378:metabolism*; D060588:LIM Domain Proteins; D060850:LIM-Homeodomain Proteins; D051379:Mice; D009132:Muscles / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D011485:Protein Binding; D054594:Protein Tyrosine Phosphatase, Non-Receptor Type 12; D017027:Protein Tyrosine Phosphatases / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D014157:Transcription Factors; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D016335:Zinc Fingers
D003598:Cytoskeletal Proteins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D060588:LIM Domain Proteins; D060850:LIM-Homeodomain Proteins; C094898:Lhx3 protein; D009419:Nerve Tissue Proteins; C090090:Tgfb1i1 protein, mouse; D014157:Transcription Factors; D016212:Transforming Growth Factor beta; D054594:Protein Tyrosine Phosphatase, Non-Receptor Type 12; D017027:Protein Tyrosine Phosphatases; C516739:Ptpn12 protein, mouse