Please use this identifier to cite or link to this item:
DC FieldValue
dc.titleThe receptor-like protein tyrosine phosphatase HPTPα has two active catalytic domains with distinct substrate specificities
dc.contributor.authorWang, V.
dc.contributor.authorPallen, C.J.
dc.identifier.citationWang, V.,Pallen, C.J. (1991). The receptor-like protein tyrosine phosphatase HPTPα has two active catalytic domains with distinct substrate specificities. EMBO Journal 10 (11) : 3231-3237. ScholarBank@NUS Repository.
dc.description.abstractCloning and expression of the homologous domains of the receptor-like tyrosine phosphatase HPTPαa shows that both domain 1 (D1) and domain 2 (D2) are enzymatically active. The two domains display different substrate specificities with D1 preferentially dephosphorylating MBP ∼ RR-src > PNPP while D2 favours PNPP ⋙ RR-src and is inactive towards MBP. Each domain has lower activity than an expressed protein containing both domains. Analysis of chimaeric D1/2 proteins suggests that no particular region of D2 is responsible for the low activity of D2 on RR-src and that the specificity differences of D1 and D2 reflect overall sequence dissimilarities. Activities of D1 and D2 are inhibited by zinc, vanadate and EDTA and differentially susceptible to inhibition by heparin and poly(Glu4:Tyr1). Unusually, the activity of the protein containing both domains is stimulated by these polyanions. Regions amino-terminal to each domain are important for catalysis since deletion of these sequences abolishes phosphatase activity. Activity of the double domain polypeptide was also lost upon deletion of the sequence amino-terminal to D1, indicating that inactivation of D1 may suppress D2 activity. Differences in substrate specificity and responses to effectors and the interdependence between the two domains are likely important properties in the function of this PTPase in signal transduction.
dc.subjectHomologous domains
dc.subjectTandem active sites
dc.subjectTyrosine dephosphorylation
dc.contributor.departmentINSTITUTE OF MOLECULAR & CELL BIOLOGY
dc.description.sourcetitleEMBO Journal
Appears in Collections:Staff Publications

Show simple item record
Files in This Item:
There are no files associated with this item.

Page view(s)

checked on Mar 30, 2023

Google ScholarTM


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.