High-resolution structural analysis of mammalian profilin 2a complex formation with two physiological ligands: The formin homology 1 domain of mDial and the proline-rich domain of VASP
High-resolution structural analysis of mammalian profilin 2a complex formation with two physiological ligands: The formin homology 1 domain of mDial and the proline-rich domain of VASP
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DOI：
10.1016/j.jmb.2007.10.050
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发表时间：
2008-01-04
影响因子：
5.6
通讯作者：
Wilmanns, Matthias
中科院分区：
文献类型：
--
作者：
Kursula, Petri;Kursula, Inari;Wilmanns, Matthias
Profilins是一种能够结合肌动蛋白、多聚L-脯氨酸等富含脯氨酸的序列以及磷脂酰肌醇(4，5)-二磷酸的小蛋白。已经确定了一些Profilin的富含Pro的配体，包括Ena/Vasp和Forin家族的蛋白质。我们已经确定了小鼠profilin 2a与来自不同家族的两个功能重要的配体Vasp和mDia1的多肽形成的复合物的高分辨晶体结构。结构分析表明，Vasp和mDia1的多肽与Profilin 2a的结合方式不同，其结合方式主要受序列中非脯氨酸残基的影响。结晶学数据的高分辨率使我们能够检测到多肽和Profilin之间保守的CH-pi氢键。两个复合体都有。此外，这两个被证明具有微摩尔亲和力的多肽都诱导了Profilin的二聚化，潜在地导致了不同的配体-Profilin-肌动蛋白复合体。在存在或不存在Profilin 2a的情况下，这些多肽对肌动蛋白聚合动力学没有显著影响。突变的Profilin与多聚L-脯氨酸、Vasp和mDial多肽以及F139A突变的富含Pro的配基具有近天然的亲和力。用一系列设计的带有Profilin1和2a的多肽进行多肽印迹表明，这两个Profilin对来自mDial和Vasp的富含Pro的多肽存在差异。我们的数据为mDial和Vasp调控的肌动蛋白聚合机制提供了结构性的见解。(C)2007爱思唯尔有限公司。保留所有权利。
Profilins are small proteins capable of binding actin, poly-L-proline and other proline-rich sequences, and phosphatidylinositol (4,5)-bisphosphate. A number of proline-rich ligands for profilin have been characterised, including proteins of the Ena/VASP and formin families. We have determined the high-resolution crystal structures of mouse profilin 2a in complex with peptides from two functionally important ligands from different families, VASP and mDia1. The structures show that the binding mode of the peptide ligand is strongly affected by the non-proline residues in the sequence, and the peptides from VASP and mDia1 bind to profilin 2a in distinct modes. The high resolution of the crystallographic data allowed us to detect conserved CH-pi hydrogen bonds between the peptide and profilin in. both complexes. Furthermore, both peptides, which are shown to have micromolar affinity, induced the dimerisation of profilin, potentially leading to functionally different ligand-profilin-actin complexes. The peptides did not significantly affect actin polymerisation kinetics in the presence or in the absence of profilin 2a. Mutant profilins were tested for binding to poly-L-proline and the VASP and mDial peptides, and the F139A mutant bound proline-rich ligands with near-native affinity. Peptide blotting using a series of designed peptides with profilins 1 and 2a indicates differences between the two profilins towards proline-rich peptides from mDial and VASP. Our data provide structural insights into the mechanisms of mDial and VASP regulated actin polymerisation. (c) 2007 Elsevier Ltd. All rights reserved.