2G62

Crystal structure of human PTPA

Summary for 2G62

• Entry DOI: 10.2210/pdb2g62/pdb
• Descriptor: protein phosphatase 2A, regulatory subunit B' (PR 53), SULFATE ION, GLYCEROL, ... (4 entities in total)
• Functional Keywords: ppp2r4, mgc2184, pp2a, pr53, ptpa, protein phosphatase 2a, regulatory subunit b' (pr 53), hydrolase activator
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 1
• Total formula weight: 37804.10

Authors

Magnusdottir, A.,Stenmark, P.,Arrowsmith, C.,Berglund, H.,Collins, R.,Edwards, A.,Ehn, M.,Flodin, S.,Flores, A.,Graslund, S.,Hammarstrom, M.,Hallberg, B.M.,Hogbom, M.,Holmberg Schiavone, L.,Kotenyova, T.,Nilsson-Ehle, P.,Nyman, T.,Ogg, D.,Persson, C.,Sagemark, J.,Sundstrom, M.,Thorsell, A.G.,Van Den Berg, S.,Wallden, K.,Weigelt, J.,Nordlund, P. (deposition date: 2006-02-24, release date: 2006-04-04, Last modification date: 2024-03-13)

Primary citation

Magnusdottir, A.,Stenmark, P.,Flodin, S.,Nyman, T.,Hammarstrom, M.,Ehn, M.,Bakali H, M.A.,Berglund, H.,Nordlund, P.
The crystal structure of a human PP2A phosphatase activator reveals a novel fold and highly conserved cleft implicated in protein-protein interactions.
J.Biol.Chem., 281:22434-22438, 2006

PubMed Abstract: Protein phosphatase 2A (PP2A) is a heterotrimeric Ser/Thr phosphatase that is involved in regulating a plethora of signaling pathways in the cell, making its regulation a critical part of the well being of the cell. For example, three of the non-catalytic PP2A subunits have been linked to carcinogenic events. Therefore, the molecular basis for the complicated protein-protein interaction pattern of PP2A and its regulators is of special interest. The PP2A phosphatase activator (PTPA) protein is highly conserved from humans to yeast. It is an activator of PP2A and has been shown to be essential for a fully functional PP2A, but its mechanism of activation is still not well defined. We have solved the crystal structure of human PTPA to 1.6A. It reveals a two-domain protein with a novel fold comprised of 13 alpha-helices. We have identified a highly conserved cleft as a potential region for interaction with peptide segments of other proteins. Binding studies with ATP and its analogs are not consistent with ATP being a cofactor/substrate for PTPA as had previously been proposed. The structure of PTPA can serve as a basis for structure-function studies directed at elucidating its mechanism as an activator of PP2A.

PubMed: 16782712
DOI: 10.1074/jbc.C600100200

Experimental method

X-RAY DIFFRACTION (1.6 Å)