Abstract
The transmembrane PTPase HPTP beta differs from its related family members in having a single rather than a tandemly duplicated cytosolic catalytic domain. We have expressed the 354-amino acid, 41-kDa human PTP beta catalytic fragment in Escherichia coli, purified it, and assessed catalytic specificity with a series of pY peptides. HPTP beta shows distinctions from the related LAR PTPase and T cell CD45 PTPase domains: it recognizes phosphotyrosyl peptides of 9-11 residues from lck, src, and PLC gamma with Km values of 2, 4, and 1 microM, some 40-200-fold lower than the other two PTPases. With kcat values of 30-205 s-1, the catalytic efficiency, kcat/Km, of the HPTP beta 41-kDa catalytic domain is very high, up to 5.7 x 10(7) M-1 s-1. The peptides corresponding to PLC gamma (766-776) and EGFR (1,167-1,177) phosphorylation sites were used for structural variation to assess pY sequence context recognition by HPTP beta catalytic domain. While exchange of the alanine residue at the +2 position of the PLC gamma (Km of 1 microM) peptide to lysine or aspartic acid showed little or no effect on substrate affinity, replacement by arginine increased the Km 35-fold. Similarly, the high Km value of the EGFR pY peptide (Km of 104 microM) derives largely from the arginine residue at the +2 position of the peptide, since arginine to alanine single mutation at the -2 position of the EGFR peptide decreased the Km value 34-fold to 3 microM. Three thiophosphotyrosyl peptides have been prepared and act as substrates and competitive inhibitors of these PTPase catalytic domains.
Full Text
The Full Text of this article is available as a PDF (1.7 MB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bialojan C., Takai A. Inhibitory effect of a marine-sponge toxin, okadaic acid, on protein phosphatases. Specificity and kinetics. Biochem J. 1988 Nov 15;256(1):283–290. doi: 10.1042/bj2560283. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cho H. J., Ramer S. E., Itoh M., Winkler D. G., Kitas E., Bannwarth W., Burn P., Saito H., Walsh C. T. Purification and characterization of a soluble catalytic fragment of the human transmembrane leukocyte antigen related (LAR) protein tyrosine phosphatase from an Escherichia coli expression system. Biochemistry. 1991 Jun 25;30(25):6210–6216. doi: 10.1021/bi00239a019. [DOI] [PubMed] [Google Scholar]
- Cho H., Ramer S. E., Itoh M., Kitas E., Bannwarth W., Burn P., Saito H., Walsh C. T. Catalytic domains of the LAR and CD45 protein tyrosine phosphatases from Escherichia coli expression systems: purification and characterization for specificity and mechanism. Biochemistry. 1992 Jan 14;31(1):133–138. doi: 10.1021/bi00116a019. [DOI] [PubMed] [Google Scholar]
- Cohen P., Klumpp S., Schelling D. L. An improved procedure for identifying and quantitating protein phosphatases in mammalian tissues. FEBS Lett. 1989 Jul 3;250(2):596–600. doi: 10.1016/0014-5793(89)80803-8. [DOI] [PubMed] [Google Scholar]
- Cooper J. A., Gould K. L., Cartwright C. A., Hunter T. Tyr527 is phosphorylated in pp60c-src: implications for regulation. Science. 1986 Mar 21;231(4744):1431–1434. doi: 10.1126/science.2420005. [DOI] [PubMed] [Google Scholar]
- Gratecos D., Fischer E. H. Adenosine 5'-O(3-thiotriphosphate) in the control of phosphorylase activity. Biochem Biophys Res Commun. 1974 Jun 18;58(4):960–967. doi: 10.1016/s0006-291x(74)80237-8. [DOI] [PubMed] [Google Scholar]
- Guan K. L., Dixon J. E. Evidence for protein-tyrosine-phosphatase catalysis proceeding via a cysteine-phosphate intermediate. J Biol Chem. 1991 Sep 15;266(26):17026–17030. [PubMed] [Google Scholar]
- Honkanen R. E., Zwiller J., Moore R. E., Daily S. L., Khatra B. S., Dukelow M., Boynton A. L. Characterization of microcystin-LR, a potent inhibitor of type 1 and type 2A protein phosphatases. J Biol Chem. 1990 Nov 15;265(32):19401–19404. [PubMed] [Google Scholar]
- Kazlauskas A., Cooper J. A. Autophosphorylation of the PDGF receptor in the kinase insert region regulates interactions with cell proteins. Cell. 1989 Sep 22;58(6):1121–1133. doi: 10.1016/0092-8674(89)90510-2. [DOI] [PubMed] [Google Scholar]
- Kim J. W., Sim S. S., Kim U. H., Nishibe S., Wahl M. I., Carpenter G., Rhee S. G. Tyrosine residues in bovine phospholipase C-gamma phosphorylated by the epidermal growth factor receptor in vitro. J Biol Chem. 1990 Mar 5;265(7):3940–3943. [PubMed] [Google Scholar]
- Lee J. P., Cho H., Bannwarth W., Kitas E. A., Walsh C. T. NMR analysis of regioselectivity in dephosphorylation of a triphosphotyrosyl dodecapeptide autophosphorylation site of the insulin receptor by a catalytic fragment of LAR phosphotyrosine phosphatase. Protein Sci. 1992 Oct;1(10):1353–1362. doi: 10.1002/pro.5560011015. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Liu J., Farmer J. D., Jr, Lane W. S., Friedman J., Weissman I., Schreiber S. L. Calcineurin is a common target of cyclophilin-cyclosporin A and FKBP-FK506 complexes. Cell. 1991 Aug 23;66(4):807–815. doi: 10.1016/0092-8674(91)90124-h. [DOI] [PubMed] [Google Scholar]
- Marth J. D., Cooper J. A., King C. S., Ziegler S. F., Tinker D. A., Overell R. W., Krebs E. G., Perlmutter R. M. Neoplastic transformation induced by an activated lymphocyte-specific protein tyrosine kinase (pp56lck). Mol Cell Biol. 1988 Feb;8(2):540–550. doi: 10.1128/mcb.8.2.540. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pot D. A., Dixon J. E. Active site labeling of a receptor-like protein tyrosine phosphatase. J Biol Chem. 1992 Jan 5;267(1):140–143. [PubMed] [Google Scholar]
- Pot D. A., Woodford T. A., Remboutsika E., Haun R. S., Dixon J. E. Cloning, bacterial expression, purification, and characterization of the cytoplasmic domain of rat LAR, a receptor-like protein tyrosine phosphatase. J Biol Chem. 1991 Oct 15;266(29):19688–19696. [PubMed] [Google Scholar]
- Ralph S. J., Thomas M. L., Morton C. C., Trowbridge I. S. Structural variants of human T200 glycoprotein (leukocyte-common antigen). EMBO J. 1987 May;6(5):1251–1257. doi: 10.1002/j.1460-2075.1987.tb02361.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ramachandran C., Aebersold R., Tonks N. K., Pot D. A. Sequential dephosphorylation of a multiply phosphorylated insulin receptor peptide by protein tyrosine phosphatases. Biochemistry. 1992 May 5;31(17):4232–4238. doi: 10.1021/bi00132a012. [DOI] [PubMed] [Google Scholar]
- Streuli M., Krueger N. X., Hall L. R., Schlossman S. F., Saito H. A new member of the immunoglobulin superfamily that has a cytoplasmic region homologous to the leukocyte common antigen. J Exp Med. 1988 Nov 1;168(5):1523–1530. doi: 10.1084/jem.168.5.1523. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Streuli M., Krueger N. X., Tsai A. Y., Saito H. A family of receptor-linked protein tyrosine phosphatases in humans and Drosophila. Proc Natl Acad Sci U S A. 1989 Nov;86(22):8698–8702. doi: 10.1073/pnas.86.22.8698. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sun I. Y., Johnson E. M., Allfrey V. G. Affinity purification of newly phosphorylated protein molecules. Thiophosphorylation and recovery of histones H1, H2B, and H3 and the high mobility group protein HMG-1 using adenosine 5'-O-(3-thiotriphosphate) and cyclic AMP-dependent protein kinase. J Biol Chem. 1980 Jan 25;255(2):742–747. [PubMed] [Google Scholar]
- Tonks N. K., Diltz C. D., Fischer E. H. Purification of the major protein-tyrosine-phosphatases of human placenta. J Biol Chem. 1988 May 15;263(14):6722–6730. [PubMed] [Google Scholar]
- Tornqvist H. E., Pierce M. W., Frackelton A. R., Nemenoff R. A., Avruch J. Identification of insulin receptor tyrosine residues autophosphorylated in vitro. J Biol Chem. 1987 Jul 25;262(21):10212–10219. [PubMed] [Google Scholar]
- Wang Y., Pallen C. J. Expression and characterization of wild type, truncated, and mutant forms of the intracellular region of the receptor-like protein tyrosine phosphatase HPTP beta. J Biol Chem. 1992 Aug 15;267(23):16696–16702. [PubMed] [Google Scholar]