The versatile molecular complex component LC8 promotes several distinct steps of flagellar assembly.
The versatile molecular complex component LC8 promotes several distinct steps of flagellar assembly.
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DOI：
10.1083/jcb.201111041
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发表时间：
2012-07-09
期刊：
影响因子：
--
通讯作者：
Yang P
中科院分区：
文献类型：
--
作者：
Gupta A;Diener DR;Sivadas P;Rosenbaum JL;Yang P
在鞭毛的尖端，LC 8二聚体的阵列与辐射状辐条前体中的辐条蛋白RSP3结合，触发磷酸化、茎基部形成和轴丝靶向。LC8存在于各种分子复合物中。然而，它在这些复合物中的作用仍不清楚。我们发现，虽然LC 8是一个亚基的辐射辐条（RS）复合体在衣原体鞭毛，它是检测不到的RS前体转化为成熟的RS在尖端的伸长轴丝。有趣的是，LC 8二聚体串联结合到辐条磷蛋白的N-末端区域，RS蛋白3（RSP3），将RS停靠到轴丝。LC8增强RSP3 N-末端片段与纯化的轴丝的结合。同样，从轴丝提取的N-末端片段含有LC 8和推定的辐条对接蛋白。最后，RSP3的LC8结合位点的扰动导致了具有低磷酸化RSP3的异步鞭毛和LC8，RS和轴丝之间的缺陷关联。我们建议，在鞭毛的尖端，一个阵列的LC 8二聚体结合到RS前体中的RSP3，触发磷酸化，茎基形成和轴丝靶向。这些多重效应揭示了关于含LC8的复合物和轴丝组装的基本问题。
At the tip of flagella, an array of LC8 dimers binds to the spoke protein RSP3 in radial spoke precursors, triggering phosphorylation, stalk base formation, and axoneme targeting. LC8 is present in various molecular complexes. However, its role in these complexes remains unclear. We discovered that although LC8 is a subunit of the radial spoke (RS) complex in Chlamydomonas flagella, it was undetectable in the RS precursor that is converted into the mature RS at the tip of elongating axonemes. Interestingly, LC8 dimers bound in tandem to the N-terminal region of a spoke phosphoprotein, RS protein 3 (RSP3), that docks RSs to axonemes. LC8 enhanced the binding of RSP3 N-terminal fragments to purified axonemes. Likewise, the N-terminal fragments extracted from axonemes contained LC8 and putative spoke-docking proteins. Lastly, perturbations of RSP3’s LC8-binding sites resulted in asynchronous flagella with hypophosphorylated RSP3 and defective associations between LC8, RSs, and axonemes. We propose that at the tip of flagella, an array of LC8 dimers binds to RSP3 in RS precursors, triggering phosphorylation, stalk base formation, and axoneme targeting. These multiple effects shed new light on fundamental questions about LC8-containing complexes and axoneme assembly.
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DOI：
10.1083/jcb.200807155
发表时间：
2009-04-20
期刊：
The Journal of cell biology
影响因子：
--
作者：
Fejtova A;Davydova D;Bischof F;Lazarevic V;Altrock WD;Romorini S;Schöne C;Zuschratter W;Kreutz MR;Garner CC;Ziv NE;Gundelfinger ED
通讯作者：
Gundelfinger ED
影响因子：
4.8
作者：
Lin, Jianfeng;Tritschler, Douglas;Nicastro, Daniela
通讯作者：
Nicastro, Daniela
影响因子：
4.9
作者：
Bergen, Jamie M.;Pun, Suzie H.
通讯作者：
Pun, Suzie H.
影响因子：
3.3
作者：
DiBella, LM;Gorbatyuk, O;King, SM
通讯作者：
King, SM
影响因子：
3.3
作者：
LEDIZET, M;PIPERNO, G
通讯作者：
PIPERNO, G