Kinesin 9 family members perform separate functions in the trypanosome flagellum
Kinesin 9 family members perform separate functions in the trypanosome flagellum
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DOI：
10.1083/jcb.200903139
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发表时间：
2009-11-30
影响因子：
7.8
通讯作者：
Kohl, Linda
中科院分区：
文献类型：
--
作者：
Demonchy, Raphael;Blisnick, Thierry;Kohl, Linda
许多真核生物基因组计划已经发现了各种未知功能的动力蛋白。动力蛋白9家族仅限于鞭毛物种。我们的系统发育实验揭示了两个亚家族：KIF9A（包括莱茵衣藻KLP1）和KIF9B（包括人类KIF6）。研究了KIF9A和KIF9B在具有单个运动鞭毛的原生布鲁氏锥虫中的功能。KIF9A和KIF9B与细胞骨架密切相关，是运动所必需的。KIF9A仅定位于轴突，其缺失导致运动改变而没有明显的结构改变。KIF9B存在于轴突和基底体中，对鞭毛旁杆（PFR）的组装至关重要，PFR是一个大的轴突外结构。在缺乏KIF9B的情况下，细胞生长出异常的鞭毛，鞭毛上有过大的pfr样物质块，与只有轴突存在的区域交替。激酶9家族的功能多样性说明了生物体适应特定细胞骨架需求的能力。
Numerous eukaryote genome projects have uncovered a variety of kinesins of unknown function. The kinesin 9 family is limited to flagellated species. Our phylogenetic experiments revealed two subfamilies: KIF9A (including Chlamydomonas reinhardtii KLP1) and KIF9B (including human KIF6). The function of KIF9A and KIF9B was investigated in the protist Trypanosoma brucei that possesses a single motile flagellum. KIF9A and KIF9B are strongly associated with the cytoskeleton and are required for motility. KIF9A is localized exclusively in the axoneme, and its depletion leads to altered motility without visible structural modifications. KIF9B is found in both the axoneme and the basal body, and is essential for the assembly of the paraflagellar rod (PFR), a large extra-axonemal structure. In the absence of KIF9B, cells grow abnormal flagella with excessively large blocks of PFR-like material that alternate with regions where only the axoneme is present. The functional diversity of the kinesin 9 family illustrates the capacity for adaptation of organisms to suit specific cytoskeletal requirements.