In:
Proteins: Structure, Function, and Bioinformatics, Wiley, Vol. 68, No. 3 ( 2007-08-15), p. 779-788
Abstract:
Inhibitor‐1α is one of the isoforms of human protein phosphatase inhibitor‐1. It is a product of alternative splicing of inhibitor‐1 gene and lacks 51 internal amino acids from residue 84 to 134 of inhibitor‐1. Here we have characterized the structural and biochemical properties of inhibitor‐1α. Structural analysis of recombinant inhibitor‐1α by NMR spectroscopy revealed that inhibitor‐1α adopts a predominantly random coil conformation. Excluding the region from residue 84 to 134 of inhibitor‐1, the structural features of inhibitor‐1 and inhibitor‐1α are almost the same as each other. The IC 50 value of inhibitor‐1α in inhibition of Protein phosphatase‐1 (PP1) is comparable to that of inhibitor‐1, indicating that inhibitor‐1α is a potent inhibitor of PP1 when Thr‐35 is phosphorylated by PKA. For phosphorylation by PKA and dephosphorylation by protein phosphatase‐1, ‐2A, and ‐2B, the measured kinetic parameters of inhibitor‐1α are very close to those of inhibitor‐1. Taken together, these results suggest that inhibitor‐1α preserves the structure of inhibitor‐1, the PP1 inhibitory activity and the functional specificities toward phosphorylation by PKA and dephosphorylation by protein phosphatase‐1, ‐2A, and ‐2B. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Type of Medium:
Online Resource
ISSN:
0887-3585
,
1097-0134
Language:
English
Publisher:
Wiley
Publication Date:
2007
detail.hit.zdb_id:
1475032-6
SSG:
12
Permalink