(1)Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
J Mol Biol. 2011 Oct 14;413(1):17-23. doi: 10.1016/j.jmb.2011.08.036. Epub 2011 Aug 22.
A group of closely related myosins is characterized by the presence of at least one MyTH/FERM (myosin tail homology; band 4.1, ezrin, radixin, moesin) domain in their C-terminal tails. This domain interacts with a variety of binding partners, and mutations in either the MyTH4 or the FERM domain of myosin VII and myosin XV result in deafness, highlighting the functional importance of each domain. The N-terminal MyTH/FERM region of Dictyostelium myosin VII (M7) has been isolated as a first step toward gaining insight into the function of this domain and its interaction with binding partners. The M7 MyTH4/FERM domain (MF1) binds to both actin and microtubules in vitro, with dissociation constants of 13.7 and 1.7 μM, respectively. Gel filtration and UV spectroscopy reveal that MF1 exists as a monomer in solution and forms a well-folded, compact conformation with a high degree of secondary structure. These results indicate that MF1 forms an integrated structural domain that serves to couple actin filaments and microtubules in specific regions of the cytoskeleton.
一组密切相关的肌球蛋白的特征是其 C 末端尾部至少存在一个 MyTH/FERM（肌球蛋白尾部同源物；带 4.1、埃兹蛋白、radixin、moesin）结构域。该结构域与各种结合伴侣相互作用，肌球蛋白 VII 和肌球蛋白 XV 的 MyTH4 或 FERM 结构域中的突变导致耳聋，突出了每个结构域的功能重要性。秀丽隐杆线虫肌球蛋白 VII（M7）的 N 端 MyTH/FERM 区域已被分离出来，作为深入了解该结构域及其与结合伴侣相互作用的第一步。M7 MyTH4/FERM 结构域（MF1）在体外与肌动蛋白和微管都结合，解离常数分别为 13.7 和 1.7 μM。凝胶过滤和紫外光谱表明，MF1 在溶液中以单体形式存在，形成一种折叠良好、紧凑的构象，具有高度的二级结构。这些结果表明，MF1 形成了一个集成的结构域，用于在细胞骨架的特定区域连接肌动蛋白丝和微管。
