A microtubule depolymerizing kinesin functions during both flagellar disassembly and flagellar assembly in Chlamydomonas
A microtubule depolymerizing kinesin functions during both flagellar disassembly and flagellar assembly in Chlamydomonas
复制标题
衣藻中微管解聚驱动蛋白在鞭毛分解和鞭毛组装过程中发挥作用
DOI：
10.1073/pnas.0808671106
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发表时间：
2009-03-24
影响因子：
11.1
通讯作者：
Pan, Junmin
中科院分区：
文献类型：
--
作者：
Piao, Tian;Luo, Minna;Pan, Junmin
纤毛和鞭毛是动态细胞器，在细胞分化、应激和细胞周期期间组装和拆卸。虽然鞭毛内运输（IFT）是有据可查的负责运输纤毛/鞭毛前体从细胞体的鞭毛，很少有人知道的分子机制动员细胞体定位的前体，使它们可用于运输过程中的细胞器组装或拆卸的微管为基础的轴丝在缩短。在这里，我们表明，衣原体驱动蛋白-13（CrKinesin-13），驱动蛋白-13家族的微管解聚驱动蛋白的成员，其在细胞周期中的作用最为知名，功能在鞭毛拆卸和鞭毛装配。激活细胞以产生新的鞭毛诱导CrKinesin-13的快速磷酸化，并且鞭毛缩短的激活诱导CrKinesin-13经由鞭毛内转运从细胞体立即转运到鞭毛中。通过RNAi耗尽CrKinesin-13的细胞在细胞分裂后组装鞭毛，但不能快速组装鞭毛，这通常发生在鞭毛脱离后。此外，它们在鞭毛缩短中受到抑制。因此，CrKinesin-13在衣原体鞭毛组装和拆卸过程中受到动态调节，并在每个鞭毛组装和拆卸过程中发挥作用。
Cilia and flagella are dynamic organelles that are assembled and disassembled during cell differentiation, during stress, and during the cell cycle. Although intraflagellar transport (IFT) is well documented to be responsible for transport of ciliary/flagellar precursors from the cell body to the flagella, little is known about the molecular mechanisms for mobilizing the cell body-localized precursors to make them available for transport during organelle assembly or for disassembling the microtubule-based axoneme during shortening. Here, we show that Chlamydomonas kinesin-13 (CrKinesin-13), a member of the kinesin-13 family of microtubule depolymerizing kinesins best known for their roles in the cell cycle, functions in flagellar disassembly and flagellar assembly. Activation of a cell to generate new flagella induces rapid phosphorylation of CrKinesin-13, and activation of flagellar shortening induces the immediate transport of CrKinesin-13 via intraflagellar transport from the cell body into the flagella. Cells depleted of CrKinesin-13 by RNAi assemble flagella after cell division but are incapable of the rapid assembly of flagella that normally occurs after flagellar detachment. Furthermore, they are inhibited in flagellar shortening. Thus, CrKinesin-13 is dynamically regulated during flagellar assembly and disassembly in Chlamydomonas and functions in each.