3EGH image
Entry Detail
PDB ID:
3EGH
Title:
Crystal structure of a complex between Protein Phosphatase 1 alpha (PP1), the PP1 binding and PDZ domains of Spinophilin and the small natural molecular toxin Nodularin-R
Biological Source:
PDB Version:
Deposition Date:
2008-09-10
Release Date:
2010-03-23
Method Details:
Experimental Method:
Resolution:
2.00 Å
R-Value Free:
0.23
R-Value Work:
0.19
R-Value Observed:
0.19
Space Group:
C 1 2 1
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Serine/threonine-protein phosphatase PP1-alpha catalytic subunit
Chain IDs:A, B
Chain Length:329
Number of Molecules:2
Biological Source:Homo sapiens
Polymer Type:polypeptide(L)
Description:Spinophilin
Chain IDs:C, D
Chain Length:170
Number of Molecules:2
Biological Source:Rattus norvegicus
Polymer Type:polypeptide(L)
Description:nodularin R
Chain IDs:E, F
Chain Length:5
Number of Molecules:2
Biological Source:Nodularia spumigena
Peptide-like Molecules
PRD_000214
Primary Citation
Spinophilin directs protein phosphatase 1 specificity by blocking substrate binding sites.
Nat.Struct.Mol.Biol. 17 459 464 (2010)
PMID: 20305656 DOI: 10.1038/nsmb.1786

Abstact

The serine/threonine protein phosphatase 1 (PP1) dephosphorylates hundreds of key biological targets. PP1 associates with >or=200 regulatory proteins to form highly specific holoenzymes. These regulatory proteins target PP1 to its point of action within the cell and prime its enzymatic specificity for particular substrates. However, how they direct PP1's specificity is not understood. Here we show that spinophilin, a neuronal PP1 regulator, is entirely unstructured in its unbound form, and it binds PP1 through a folding-upon-binding mechanism in an elongated fashion, blocking one of PP1's three putative substrate binding sites without altering its active site. This mode of binding is sufficient for spinophilin to restrict PP1's activity toward a model substrate in vitro without affecting its ability to dephosphorylate its neuronal substrate, glutamate receptor 1 (GluR1). Thus, our work provides the molecular basis for the ability of spinophilin to dictate PP1 substrate specificity.

Legend

Protein

Chemical

Disease

Primary Citation of related structures