4MEW: Structure Of The Core Fragment Of Human Pr70

Citation:
Abstract
Protein Phosphatase 2A (PP2A) is a major Ser/Thr phosphatase involved in the regulation of various cellular processes. PP2A assembles into diverse trimeric holoenzymes, which consist of a scaffolding (A) subunit, a catalytic (C) subunit and various regulatory (B) subunits. Here we report a 2.0 A crystal structure of the free B''/PR70 subunit and a SAXS model of an A/PR70 complex. The crystal structure of B''/PR70 reveals a two domain elongated structure with two Ca2+ binding EF-hands. Furthermore, we have characterized the interaction of both binding partner and their calcium dependency using biophysical techniques. Ca2+ biophysical studies with Circular Dichroism showed that the two EF-hands display different affinities to Ca2+. In the absence of the catalytic C-subunit, the scaffolding A-subunit remains highly mobile and flexible even in the presence of the B''/PR70 subunit as judged by SAXS. Isothermal Titration Calorimetry studies and SAXS data support that PR70 and the A-subunit have high affinity to each other. This study provides additional knowledge about the structural basis for the function of B'' containing holoenzymes.
PDB ID: 4MEWDownload
MMDB ID: 122326
PDB Deposition Date: 2013/8/27
Updated in MMDB: 2014/08
Experimental Method:
x-ray diffraction
Resolution: 1.99  Å
Source Organism:
Similar Structures:
Biological Unit for 4MEW: monomeric; determined by author and by software (PISA)
Molecular Components in 4MEW
Label Count Molecule
Protein (1 molecule)
1
Serine/threonine-protein Phosphatase 2A Regulatory Subunit B'' Subunit Beta(Gene symbol: PPP2R3B)
Molecule annotation
Chemicals (4 molecules)
1
2
2
2
* Click molecule labels to explore molecular sequence information.

Citing MMDB
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