The fimbrin and alpha-actinin footprint on actin.
The fimbrin and alpha-actinin footprint on actin.
复制标题
DOI：
10.1083/jcb.126.2.285
复制
发表时间：
1994-07
期刊：
影响因子：
--
通讯作者：
Matsudaira P
中科院分区：
文献类型：
--
作者：
Matsudaira P
怀特黑德生物医学研究所和马萨诸塞州理工学院生物系，剑桥，马萨诸塞州02142当来自几个领域的信息汇集在一起，对一个重要问题给出一个大的图景时，就会出现令人满意的科学经验。在三篇论文（Holtzman等人，1994; Honts等人，1994; McGough等人，1994年），在这一期的细胞生物学杂志中，遗传学和结构生物学的学科已经揭示了两种肌动蛋白交联蛋白，fimplatin和α-辅肌动蛋白，结合到肌动蛋白上的同一区域。因为这两种蛋白质都属于肌动蛋白交联蛋白超家族，我们有一定的信心，该超家族的其他成员，包括细丝蛋白，血影蛋白，肌营养不良蛋白和ABP-120，也结合相同的肌动蛋白区域。这些结合位点的信息是理解肌动蛋白纤维是如何通过交联蛋白质形成纤维束和超分子网络的重要一步。这个故事植根于肌肉蛋白质的经典生物化学研究。α-辅肌动蛋白首先从骨骼肌中纯化（Maruyama和Ebashi，1965年），并表征为Z线组分;其棒状形状通过电子显微镜显示（见Meyer和Aebi，1990年）。后来，受到细胞生物学家的刺激，他们证明了noumuscle细胞的细胞质提取物可以进行可逆的溶胶凝胶转化，一代生物学家从阿米巴中分离并表征了许多肌动蛋白凝胶化和成束蛋白，包括ABP-280和细丝蛋白、speetrin、肌成束蛋白和ABP-120（综述于Pollard和库珀，1986; Stossel等人，1985; Weeds，1982）; α-辅肌动蛋白作为非肌肉肌动蛋白交联蛋白被重新发现（Burridge和Feramisco，1981）。在20世纪80年代后期，eDNA测序显示，这些胶凝因子中的许多属于共享共同的27-kD NH 2-末端结构域的超家族（Baron等人，1987），结合肌动蛋白丝。纤维束在肠刷状缘微绒毛中将肌动蛋白丝束成束，并且它也位于肌动蛋白束终止于膜粘附斑的地方（Bretscher和Weber，1980）。序列数据库（de Arruda et al.，1990）表明，fimmunoglobulin也参与细胞转化（Lin等，1994），并且当白细胞被生长因子和有丝分裂原激活时，它是磷酸化的靶标（Zu et al.，1990年）。因此，纤维蛋白酶也被称为plastin和pp 70。
Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142 satisfying experience in science occurs when information from several areas converge to give a big picture about an important problem. In three papers (Holtzman et al., 1994; Honts et al., 1994; McGough et al., 1994) in this issue of The Journal of Cell Biology, the disciplines of genetics and structural biology have revealed that two actin cross-linking proteins, fimbrin and alpha-actinin, bind to the same region on actin. Because both proteins belong to a superfamily of actin cross-linking proteins, we have some confidence that other members of the superfamily, including filamin, spectrin, dystrophin, and ABP-120, also bind the same region of actin. This information about binding sites is an important step toward understanding how actin illaments are organized by cross-linking proteins into bundles and supramolecular networks. This story is rooted in the classic biochemical studies of muscle proteins. Alpha-actinin was first purified from skeletal muscle (Maruyama and Ebashi, 1965) and characterized as a Z-line component; its rodlike shape was revealed by electron microscopy (see Meyer and Aebi, 1990). Later, spurred by cell biologists who demonstrated that cytoplasmic extracts of noumuscle cells could undergo reversible solgel transformations, a generation of biologists isolated and characterized a number of actin gelation and bundling proteins, including ABP-280 and filamin, speetrin, fascin, and ABP-120, from ameba (reviewed in Pollard and Cooper, 1986; Stossel et al., 1985; Weeds, 1982); alpha-actinin was rediscovered as a nonmuscle actin cross-linking protein (Burridge and Feramisco, 1981). During the late 1980's, eDNA sequencing showed that many of these gelation factors belonged to a superfamily that shares a common 27-kD NH2-terminal domain (Baron et al., 1987) that binds actin filaments. Fimbrin bundles actin filaments in intestinal brush border microvilli, and it is also located where actin bundles terminate at membrane adhesion plaques (Bretscher and Weber, 1980). The sequence databases (de Arruda et al., 1990) showed that fimbrin was also involved in cell transformation (Lin et al., 1994), and that it was a target of phosphorylation when leukocytes are activated by growth factors and mitogens (Zu et al., 1990). Hence, fimbrin is also called plastin and pp70.