7DJM

Structure of four truncated and mutated forms of quenching protein

Summary for 7DJM

• Entry DOI: 10.2210/pdb7djm/pdb
• Descriptor: Protein SUPPRESSOR OF QUENCHING 1, chloroplastic, ACETATE ION, 2,3-DIHYDROXY-1,4-DITHIOBUTANE, ... (5 entities in total)
• Functional Keywords: suppressor, quenching, plant protein
• Biological source: Arabidopsis thaliana (thale cress)
• Total number of polymer chains: 1
• Total formula weight: 54418.81

Authors

Yu, G.M.,Pan, X.W.,Li, M. (deposition date: 2020-11-20, release date: 2022-06-08, Last modification date: 2023-11-29)

Primary citation

Yu, G.,Hao, J.,Pan, X.,Shi, L.,Zhang, Y.,Wang, J.,Fan, H.,Xiao, Y.,Yang, F.,Lou, J.,Chang, W.,Malnoe, A.,Li, M.
Structure of Arabidopsis SOQ1 lumenal region unveils C-terminal domain essential for negative regulation of photoprotective qH.
Nat.Plants, 8:840-855, 2022

PubMed Abstract: Non-photochemical quenching (NPQ) plays an important role for phototrophs in decreasing photo-oxidative damage. qH is a sustained form of NPQ and depends on the plastid lipocalin (LCNP). A thylakoid membrane-anchored protein SUPPRESSOR OF QUENCHING1 (SOQ1) prevents qH formation by inhibiting LCNP. SOQ1 suppresses qH with its lumen-located thioredoxin (Trx)-like and NHL domains. Here we report structural data, genetic modification and biochemical characterization of Arabidopsis SOQ1 lumenal domains. Our results show that the Trx-like and NHL domains are associated together, with the cysteine motif located at their interface. Residue E859, required for SOQ1 function, is pivotal for maintaining the Trx-NHL association. Importantly, the C-terminal region of SOQ1 forms an independent β-stranded domain that has structural homology to the N-terminal domain of bacterial disulfide bond protein D and is essential for negative regulation of qH. Furthermore, SOQ1 is susceptible to cleavage at the loops connecting the neighbouring lumenal domains both in vitro and in vivo, which could be a regulatory process for its suppression function of qH.

PubMed: 35798975
DOI: 10.1038/s41477-022-01177-z

Experimental method

X-RAY DIFFRACTION (1.70000117792 Å)