Release of intact microtubule-capping structures from Tetrahymena cilia
Release of intact microtubule-capping structures from Tetrahymena cilia
复制标题
从四膜虫纤毛中释放完整的微管帽结构
作者：
K. Suprenant;W. Dentler
睫状体微管的远端通过微管帽结构附着在膜上。加帽结构位于微管蛋白在体内的添加和丢失的位点，并且可能是指导纤毛和鞭毛微管组装的调节系统的一部分。本研究描述了微管帽结构的释放和稳定的条件，作为其纯化的第一步。两种类型的帽状结构，远端丝和中央微管帽，选择性地和独立地从轴丝释放的CaCl 2和MgCl 2，但不是由MgSO 4，ZnCl 2，NaCl，KCl，或KI。帽和细丝的释放是特定的Ca+2，Mg+2和Cl-，而不仅仅是离子强度的函数。帽状结构被释放，而不会对轴丝结构造成重大破坏。除了提供一种手段来纯化和鉴定的帽和细丝组件，这些结果表明，在微管生长或缩短期间，它们与轴丝的结合可能受到调制的方式。该报告还揭示了远端细丝由两个可分离的组分组成，一个插入每个A-小管末端的小珠和一个“Y”形塞和细丝，它们穿过珠。
The distal ends of ciliary microtubules are attached to the membrane by microtubule-capping structures. The capping structures are located at the sites of tubulin addition and loss in vivo and may be part of the regulatory system that directs ciliary and flagellar microtubule assembly. This study describes conditions for the release and stabilization of microtubule capping structures as a first step in their purification. Two types of capping structures, the distal filaments and the central microtubule caps, are selectively and independently released from the axoneme by CaCl2 and MgCl2 but not by MgSO4, ZnCl2, NaCl, KCl, or KI. The release of the caps and filaments is specific for Ca+2, Mg+2, and Cl- and is not simply a function of ionic strength. The capping structures are released without major disruption of the axonemal structure. In addition to providing a means to purify and identify the cap and filament components, these results suggest ways in which their binding to the axoneme may be modulated during periods of microtubule growth or shortening. This report also reveals that the distal filaments are composed of two separable components, a small bead inserted into the end of each A-tubule and a "Y"-shaped plug and filament that slips through the bead.
影响因子：
4
作者：
Tamm,SL;Tamm,S
通讯作者：
Tamm,S