Back to Search
Start Over
Intact LIM 3 and LIM 4 domains of paxillin are required for the association to a novel polyproline region (Pro 2) of protein-tyrosine phosphatase-PEST.
- Source :
-
The Journal of biological chemistry [J Biol Chem] 1999 Jul 16; Vol. 274 (29), pp. 20550-60. - Publication Year :
- 1999
-
Abstract
- The focal adhesion protein p130(Cas) was identified as a substrate for the protein-tyrosine phosphatase (PTP)-PEST, and the specificity of this interaction is mediated by a dual mechanism involving a Src homology 3 domain-mediated binding and PTP domain recognition. Recently, paxillin was also demonstrated to interact with PTP-PEST (Shen, Y., Schneider, G., Cloutier, J. F., Veillette, A., and Schaller, M. D. (1998) J. Biol. Chem. 273, 6474-6481). In the present study, we show that amino acids 344-397 of PTP-PEST are sufficient for the binding to paxillin. We demonstrate that a proline-rich segment of PTP-PEST (Pro 2), 355PPEPHPVPPILTPSPPSAFP374, is essential for this interaction in vivo. Furthermore, mutation of proline residues within the Pro 2 motif reveal that proline 362 is critical for the binding of paxillin. Conversely, using deletion and point mutants of paxillin, LIM 3 and 4 domains were both found to be necessary for binding of PTP-PEST. Finally, using a "substrate trapping" approach, we demonstrate that, unlike p130(Cas), paxillin is not a substrate for PTP-PEST. In conclusion, we show that a novel proline-rich motif found in PTP-PEST serves as a ligand for the LIM domains of paxillin. Interestingly, the focal adhesion targeting of paxillin is mediated by LIM 3. Thus, we propose that PTP-PEST, by a competition with the ligand of paxillin in the focal adhesion complex, could contribute to the removal of paxillin from the adhesion sites and consequently promote focal adhesion turnover.
- Subjects :
- Amino Acid Sequence
Animals
Base Sequence
Cell Line
Crk-Associated Substrate Protein
Cytoskeletal Proteins chemistry
DNA Primers
GRB2 Adaptor Protein
Humans
Mice
Molecular Sequence Data
Mutagenesis, Site-Directed
Paxillin
Phosphoproteins chemistry
Protein Binding
Protein Tyrosine Phosphatase, Non-Receptor Type 12
Protein Tyrosine Phosphatases metabolism
Proteins metabolism
Retinoblastoma-Like Protein p130
Shc Signaling Adaptor Proteins
Src Homology 2 Domain-Containing, Transforming Protein 1
Adaptor Proteins, Signal Transducing
Adaptor Proteins, Vesicular Transport
Cytoskeletal Proteins metabolism
Phosphoproteins metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0021-9258
- Volume :
- 274
- Issue :
- 29
- Database :
- MEDLINE
- Journal :
- The Journal of biological chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 10400685
- Full Text :
- https://doi.org/10.1074/jbc.274.29.20550