Bhogaraju Sagar, Weber Kristina, Engel Benjamin D, Lechtreck Karl-Ferdinand, Lorentzen Esben
Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Martinsried, Germany.
Bioessays. 2014 May;36(5):463-7. doi: 10.1002/bies.201400007. Epub 2014 Mar 10.
Cilia are microtubule-based hair-like structures that project from the surfaces of eukaryotic cells. Cilium formation relies on intraflagellar transport (IFT) to move ciliary proteins such as tubulin from the site of synthesis in the cell body to the site of function in the cilium. A large protein complex (the IFT complex) is believed to mediate interactions between cargoes and the molecular motors that walk along axonemal microtubules between the ciliary base and tip. A recent study using purified IFT complexes has identified a tubulin-binding module in the two core IFT proteins IFT74 and IFT81 that likely serves to bind and transport tubulin within cilia. Here, we calculate the amount of tubulin required to support the observed cilium assembly kinetics and explore the possibility of multiple tubulin binding sites within the IFT complex.
纤毛是基于微管的毛发状结构，从真核细胞表面伸出。纤毛形成依赖于鞭毛内运输（IFT），将诸如微管蛋白等纤毛蛋白从细胞体中的合成位点移动到纤毛中的功能位点。一种大型蛋白质复合物（IFT复合物）被认为介导货物与沿着纤毛基部和顶端之间的轴丝微管行走的分子马达之间的相互作用。最近一项使用纯化的IFT复合物的研究在两种核心IFT蛋白IFT74和IFT81中鉴定出一个微管蛋白结合模块，该模块可能用于在纤毛内结合和运输微管蛋白。在这里，我们计算支持观察到的纤毛组装动力学所需的微管蛋白量，并探索IFT复合物内多个微管蛋白结合位点的可能性。
