Niebuhr K, Ebel F, Frank R, Reinhard M, Domann E, Carl U D, Walter U, Gertler F B, Wehland J, Chakraborty T
Abteilung Zellbiologie und Immunologie/AG Molekulare Erkennung, Mascheroder Weg 1, 38124 Braunschweig, Germany.
EMBO J. 1997 Sep 1;16(17):5433-44. doi: 10.1093/emboj/16.17.5433.
The ActA protein of the intracellular pathogen Listeria monocytogenes induces a dramatic reorganization of the actin-based cytoskeleton. Two profilin binding proteins, VASP and Mena, are the only cellular proteins known so far to bind directly to ActA. This interaction is mediated by a conserved module, the EVH1 domain. We identify E/DFPPPPXD/E, a motif repeated 4-fold within the primary sequence of ActA, as the core of the consensus ligand for EVH1 domains. This motif is also present and functional in at least two cellular proteins, zyxin and vinculin, which are in this respect major eukaryotic analogs of ActA. The functional importance of the novel protein-protein interaction was examined in the Listeria system. Removal of EVH1 binding sites on ActA reduces bacterial motility and strongly attenuates Listeria virulence. Taken together we demonstrate that ActA-EVH1 binding is a paradigm for a novel class of eukaryotic protein-protein interactions involving a proline-rich ligand that is clearly different from those described for SH3 and WW/WWP domains. This class of interactions appears to be of general importance for processes dependent on rapid actin remodeling.
细胞内病原体单核细胞增生李斯特菌的肌动蛋白激活蛋白(ActA)可诱导基于肌动蛋白的细胞骨架发生显著重组。两种富含脯氨酸的肌动蛋白结合蛋白,血管舒张刺激蛋白(VASP)和 Enabled蛋白(Mena),是目前已知的仅有的能直接与ActA结合的细胞蛋白。这种相互作用由一个保守模块——EVH1结构域介导。我们确定了E/DFPPPPXD/E,这是ActA一级序列中重复4次的基序,是EVH1结构域共有配体的核心。该基序在至少两种细胞蛋白斑联蛋白和纽蛋白中也存在且具有功能,在这方面它们是ActA的主要真核类似物。在李斯特菌系统中研究了这种新型蛋白质 - 蛋白质相互作用的功能重要性。去除ActA上的EVH1结合位点会降低细菌的运动性,并强烈减弱李斯特菌的毒力。综上所述,我们证明ActA-EVH1结合是一类新型真核蛋白质 - 蛋白质相互作用的范例,这类相互作用涉及一种富含脯氨酸的配体,它与那些描述的SH3和WW/WWP结构域明显不同。这类相互作用对于依赖快速肌动蛋白重塑的过程似乎具有普遍重要性。