4YZG

Structure of the Arabidopsis TAP38/PPH1, a state-transition phosphatase responsible for dephosphorylation of LHCII

Summary for 4YZG

• Entry DOI: 10.2210/pdb4yzg/pdb
• Related: 4YZH
• Descriptor: Protein phosphatase 2C 57, MANGANESE (II) ION, SULFATE ION, ... (4 entities in total)
• Functional Keywords: state transition, photosynthesis, pp2c phosphatase, hydrolase
• Biological source: Arabidopsis thaliana (Mouse-ear cress)
• Total number of polymer chains: 2
• Total formula weight: 67831.60

Authors

Wei, X.P.,Guo, J.T.,Li, M.,Liu, Z.F. (deposition date: 2015-03-25, release date: 2015-04-29, Last modification date: 2023-11-08)

Primary citation

Wei, X.,Guo, J.,Li, M.,Liu, Z.
Structural Mechanism Underlying the Specific Recognition between the Arabidopsis State-Transition Phosphatase TAP38/PPH1 and Phosphorylated Light-Harvesting Complex Protein Lhcb1
Plant Cell, 27:1113-1127, 2015

PubMed Abstract: During state transitions, plants regulate energy distribution between photosystems I and II through reversible phosphorylation and lateral migration of the major light-harvesting complex LHCII. Dephosphorylation of LHCII and the transition from state 2 to state 1 requires a thylakoid membrane-associated phosphatase named TAP38 or PPH1. TAP38/PPH1 specifically targets LHCII but not the core subunits of photosystem II, whereas the underlying molecular mechanism of their mutual recognition is currently unclear. Here, we present the structures of Arabidopsis thaliana TAP38/PPH1 in the substrate-free and substrate-bound states. The protein contains a type 2C serine/threonine protein phosphatase (PP2C) core domain, a Mn(2+) (or Mg(2+)) binuclear center and two additional motifs contributing to substrate recognition. A 15-mer phosphorylated N-terminal peptide of Lhcb1 binds to TAP38/PPH1 on two surface clefts enclosed by the additional motifs. The first segment of the phosphopeptide is clamped by a pair of tooth-like arginine residues at Cleft 1 site. The binding adopts the lock-and-key mechanism with slight rearrangement of the substrate binding residues on TAP38/PPH1. Meanwhile, a more evident substrate-induced fitting occurs on Cleft 2 harboring the extended part of the phosphopeptide. The results unravel the bases for the specific recognition between TAP38/PPH1 and phosphorylated Lhcb1, a crucial step in state transitions.

PubMed: 25888588
DOI: 10.1105/tpc.15.00102

Experimental method

X-RAY DIFFRACTION (1.6 Å)