Dominguez Roberto
Boston Biomedical Research Institute, 64 Grove Street, Watertown, MA 02472, USA.
Trends Biochem Sci. 2004 Nov;29(11):572-8. doi: 10.1016/j.tibs.2004.09.004.
Actin participates in more protein-protein interactions than any other known protein, including the interaction of actin with itself to form the helical polymer F-actin. The vast majority of actin-binding proteins (ABPs) can be grouped into conserved families. Only a handful of structures of complexes of actin with ABPs have been determined so far. These structures are starting to reveal how certain ABPs, including gelsolin, vitamin D-binding protein and Wiskott-Aldrich syndrome protein (WASP)-homology domain-2-related proteins, share a common actin-binding motif. It is proposed here that other ABPs, including actin itself, might share this motif, providing a mechanism whereby ABPs and actin compete for a common binding site. Of particular interest is a hydrophobic pocket that mediates important interactions in five of the existing structures of actin complexes. As the pocket remains accessible in F-actin, it is proposed that this pocket represents a primary target for F-actin-binding proteins, such as calponin-homology-related proteins and myosin.
与任何其他已知蛋白质相比，肌动蛋白参与的蛋白质 - 蛋白质相互作用更多，包括肌动蛋白自身相互作用形成螺旋聚合物F - 肌动蛋白。绝大多数肌动蛋白结合蛋白（ABP）可归为保守家族。到目前为止，仅确定了少数肌动蛋白与ABP复合物的结构。这些结构开始揭示某些ABP，包括凝溶胶蛋白、维生素D结合蛋白和威斯科特 - 奥尔德里奇综合征蛋白（WASP）同源结构域2相关蛋白，如何共享一个共同的肌动蛋白结合基序。本文提出，包括肌动蛋白自身在内的其他ABP可能共享此基序，从而提供一种ABP与肌动蛋白竞争共同结合位点的机制。特别令人感兴趣的是一个疏水口袋，它在现有的五个肌动蛋白复合物结构中介导重要相互作用。由于该口袋在F - 肌动蛋白中仍然可及，因此有人提出该口袋代表F - 肌动蛋白结合蛋白（如钙调蛋白同源相关蛋白和肌球蛋白）的主要靶点。
