2PF4

Crystal structure of the full-length simian virus 40 small t antigen complexed with the protein phosphatase 2A Aalpha subunit

Summary for 2PF4

• Entry DOI: 10.2210/pdb2pf4/pdb
• Related: 2IAE
• Descriptor: Serine/threonine-protein phosphatase 2A 65 kDa regulatory subunit A alpha isoform, Small T antigen, ZINC ION (3 entities in total)
• Functional Keywords: pp2a, sv40, small t, dnaj, aalpha subunit, hydrolase regulator-viral protein complex, hydrolase regulator/viral protein
• Biological source: Mus musculus (house mouse); More
• Cellular location: Cytoplasm : Q76MZ3
• Total number of polymer chains: 8
• Total formula weight: 344169.33

Authors

Cho, U.,Morrone, S.,Xu, W. (deposition date: 2007-04-03, release date: 2007-08-07, Last modification date: 2023-08-30)

Primary citation

Cho, U.S.,Morrone, S.,Sablina, A.A.,Arroyo, J.D.,Hahn, W.C.,Xu, W.
Structural basis of PP2A inhibition by small t antigen.
Plos Biol., 5:e202-e202, 2007

PubMed Abstract: The SV40 small t antigen (ST) is a potent oncoprotein that perturbs the function of protein phosphatase 2A (PP2A). ST directly interacts with the PP2A scaffolding A subunit and alters PP2A activity by displacing regulatory B subunits from the A subunit. We have determined the crystal structure of full-length ST in complex with PP2A A subunit at 3.1 A resolution. ST consists of an N-terminal J domain and a C-terminal unique domain that contains two zinc-binding motifs. Both the J domain and second zinc-binding motif interact with the intra-HEAT-repeat loops of HEAT repeats 3-7 of the A subunit, which overlaps with the binding site of the PP2A B56 subunit. Intriguingly, the first zinc-binding motif is in a position that may allow it to directly interact with and inhibit the phosphatase activity of the PP2A catalytic C subunit. These observations provide a structural basis for understanding the oncogenic functions of ST.

PubMed: 17608567
DOI: 10.1371/journal.pbio.0050202

Experimental method

X-RAY DIFFRACTION (3.1 Å)