scholarly journals Tyr306 near the C-terminus of protein phosphatase-1 affects enzyme stability and inhibitor binding

IUBMB Life ◽  
2011 ◽  
Vol 63 (7) ◽  
pp. 574-581
Author(s):  
Bai J. Wang ◽  
Wei Tang ◽  
Peng Zhang ◽  
Qun Wei
2004 ◽  
Vol 279 (47) ◽  
pp. 48904-48914 ◽  
Author(s):  
Douglas C. Weiser ◽  
Suzanne Sikes ◽  
Shi Li ◽  
Shirish Shenolikar

1998 ◽  
Vol 336 (3) ◽  
pp. 699-704 ◽  
Author(s):  
Christopher G. ARMSTRONG ◽  
Martin J. DOHERTY ◽  
Patricia T. W. COHEN

Deletion and mutational analyses of the rat liver glycogen-targeting subunit (GL) of protein phosphatase 1 (PP1) have identified three separate domains that are responsible for binding of PP1, glycogen and phosphorylase a. The glycogen-binding domain spans the centre of GL between residues 144 and 231 and appears to be distinct from the glycogen-binding (storage) site of phosphorylase. The regulatory high-affinity binding site for phosphorylase a lies in the 16 amino acids at the C-terminus of GL. The PP1-binding domain is deduced to comprise the -RVXF- motif [Egloff, Johnson, Moorhead, Cohen and Barford (1997) EMBO J. 16, 1876–1887] located at residues 61–64 of GL and preceding lysine residues at positions 56, 57 and 59. A possible approach for increasing glycogen synthesis in certain disorders is discussed.


2021 ◽  
Vol 22 (8) ◽  
pp. 3889
Author(s):  
Weiming Ouyang ◽  
David M. Frucht

Constitutive photomorphogenic 1 (COP1) is the ubiquitin E3 ligase that mediates degradation of c-Jun protein upon Erk1/2 inactivation. It remains unknown how this protein degradation pathway is regulated. In this study, we investigated the roles of protein phosphatases, ubiquitin-conjugating E2 enzymes (UBE2), and an intrinsic motif of c-Jun in regulating this degradation pathway. By using pharmacological inhibitors and/or gene knockdown techniques, we identified protein phosphatase 1 (PP1) and PP2A as the phosphatases and UBE23d as the UBE2 promoting c-Jun degradation, triggered by Erk1/2 inactivation. In addition, we report that the C-terminus of c-Jun protein facilitates its degradation. The addition of a C-terminal tag or deletion of the last four amino acid residues from the C-terminus of c-Jun protects it from degradation under Erk1/2-inactivating conditions. Taken together, this study reveals that the Erk1/2 inactivation-triggered and COP1-mediated c-Jun degradation is extrinsically and intrinsically regulated, providing a new understanding of the mechanisms underlying this protein degradation pathway.


2000 ◽  
Vol 352 (3) ◽  
pp. 651-658 ◽  
Author(s):  
Monique BEULLENS ◽  
Veerle VULSTEKE ◽  
Aleyde VAN EYNDE ◽  
Izabela JAGIELLO ◽  
Willy STALMANS ◽  
...  

Nuclear inhibitor of protein phosphatase-1 (NIPP1; 351 residues) is a nuclear RNA-binding protein that also contains in its central domain two contiguous sites of interaction with the catalytic subunit of protein phosphatase-1 (PP1C). We show here that mutation of these phosphatase-interaction sites did not completely abolish the ability of NIPP1 to bind and inhibit PP1C. This could be accounted for by an additional inhibitory phosphatase-binding site in the C-terminal region (residues 311Ő351), with an inhibitory core corresponding to residues 331Ő337. Following mutation of all three PP1C-binding sites in the central and C-terminal domains, NIPP1 no longer interacted with PP1C. Remarkably, while both NIPP1 domains inhibited the phosphorylase phosphatase activity of PP1C independently, mutation of either domain completely abolished the ability of NIPP1 to inhibit the dephosphorylation of myelin basic protein. The inhibitory potency of the C-terminal site of NIPP1 was decreased by phosphorylation of Tyr-335 and by the addition of RNA. Tyr-335 could be phosphorylated by tyrosine kinase Lyn, but only in the presence of RNA. In conclusion, NIPP1 contains two phosphatase-binding domains that function co-operatively but which are controlled independently. Our data are in agreement with a shared-site model for the interaction of PP1C with its regulatory subunits.


2004 ◽  
Vol 279 (41) ◽  
pp. 43198-43206 ◽  
Author(s):  
Jason T. Maynes ◽  
Kathleen R. Perreault ◽  
Maia M. Cherney ◽  
Hue Anh Luu ◽  
Michael N. G. James ◽  
...  

Diabetes ◽  
1996 ◽  
Vol 45 (3) ◽  
pp. 322-327 ◽  
Author(s):  
E. D. Crook ◽  
D. A. McClain

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