4NY3

Human PTPA in complex with peptide

Summary for 4NY3

• Entry DOI: 10.2210/pdb4ny3/pdb
• Descriptor: Serine/threonine-protein phosphatase 2A activator, Serine/threonine-protein phosphatase 2A catalytic subunit alpha isoform, SULFATE ION, ... (5 entities in total)
• Functional Keywords: ptpa, ppp2r4, regulatory subunit b' (pr 53), hydrolase activator, protein phosphatase 2a (pp2a)
• Biological source: Homo sapiens (human); More
• Cellular location: Cytoplasm: Q15257 P67775
• Total number of polymer chains: 4
• Total formula weight: 72550.85

Authors

Loew, C.,Quistgaard, E.M.,Nordlund, P. (deposition date: 2013-12-10, release date: 2014-07-23, Last modification date: 2024-02-28)

Primary citation

Low, C.,Quistgaard, E.M.,Kovermann, M.,Anandapadamanaban, M.,Balbach, J.,Nordlund, P.
Structural basis for PTPA interaction with the invariant C-terminal tail of PP2A.
Biol.Chem., 395:881-889, 2014

PubMed Abstract: Protein phosphatase 2A (PP2A) is a highly abundant heterotrimeric Ser/Thr phosphatase involved in the regulation of a variety of signaling pathways. The PP2A phosphatase activator (PTPA) is an ATP-dependent activation chaperone, which plays a key role in the biogenesis of active PP2A. The C-terminal tail of the catalytic subunit of PP2A is highly conserved and can undergo a number of posttranslational modifications that serve to regulate the function of PP2A. Here we have studied structurally the interaction of PTPA with the conserved C-terminal tail of the catalytic subunit carrying different posttranslational modifications. We have identified an additional interaction site for the invariant C-terminal tail of the catalytic subunit on PTPA, which can be modulated via posttranslational modifications. We show that phosphorylation of Tyr307(PP2A-C) or carboxymethylation of Leu309(PP2A-C) abrogates or diminishes binding of the C-terminal tail, whereas phosphorylation of Thr304(PP2A-C) is of no consequence. We suggest that the invariant C-terminal residues of the catalytic subunit can act as affinity enhancer for different PP2A interaction partners, including PTPA, and a different 'code' of posttranslational modifications can favour interactions to one subunit over others.

PubMed: 25003389
DOI: 10.1515/hsz-2014-0106

Experimental method

X-RAY DIFFRACTION (1.797 Å)