6IQF

crystal structure of Arabidopsis thaliana Profilin 3

6IQF の概要

• エントリーDOI: 10.2210/pdb6iqf/pdb
• 分子名称: PRF3 (2 entities in total)
• 機能のキーワード: actin binding, regulate actin network, plant protein
• 由来する生物種: Arabidopsis thaliana (Mouse-ear cress)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 14045.96

構造登録者

Qiao, Z.,Gao, Y. (登録日: 2018-11-07, 公開日: 2019-11-06, 最終更新日: 2023-11-22)

主引用文献

Qiao, Z.,Sun, H.,Ng, J.T.Y.,Ma, Q.,Koh, S.H.,Mu, Y.,Miao, Y.,Gao, Y.G.
Structural and computational examination of theArabidopsisprofilin-Poly-P complex reveals mechanistic details in profilin-regulated actin assembly.
J.Biol.Chem., 294:18650-18661, 2019

PubMed Abstract: Profilins are abundant cytosolic proteins that are universally expressed in eukaryotes and that regulate actin filament elongation by binding to both monomeric actin (G-actin) and formin proteins. The atypical profilin AtPRF3 has been reported to cooperate with canonical profilin isoforms in suppressing formin-mediated actin polymerization during plant innate immunity responses. AtPRF3 has a 37-amino acid-long N-terminal extension (NTE), and its suppressive effect on actin assembly is derived from enhanced interaction with the polyproline (Poly-P) of the formin AtFH1. However, the molecular mechanism remains unclear. Here, we solved the crystal structures of AtPRF3Δ22 and AtPRF3Δ37, as well as AtPRF2 apo form and in complex with AtFH1 Poly-P at 1.5-3.6 Å resolutions. By combining these structures with molecular modeling, we found that AtPRF3Δ22 NTE has high plasticity, with a primary "closed" conformation that can adopt an open conformation that enables Poly-P binding. Furthermore, using molecular dynamics simulation and free-energy calculations of protein-protein binding, along with experimental validation, we show that the AtPRF3Δ22 binds to Poly-P in an adaptive manner, thereby enabling different binding modes that maintain the interaction through disordered sequences. Together, our structural and simulation results suggest that the dynamic conformational changes of the AtPRF3 NTE upon Poly-P binding modulate their interactions to fine-tune formin-mediated actin assembly.

PubMed: 31653702
DOI: 10.1074/jbc.RA119.011307

実験手法

X-RAY DIFFRACTION (1.457 Å)