Domains in the 1alpha dynein heavy chain required for inner arm assembly and flagellar motility in Chlamydomonas.
Domains in the 1alpha dynein heavy chain required for inner arm assembly and flagellar motility in Chlamydomonas.
复制标题
在衣原体中，内臂组件和鞭毛运动所需的1α动力蛋白重链中的域。
DOI：
10.1083/jcb.146.4.801
复制
发表时间：
1999-08-23
影响因子：
7.8
通讯作者：
Porter, M E
中科院分区：
文献类型：
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作者：
Myster, S H;Knott, J A;Wysocki, K M;O'Toole, E;Porter, M E
鞭毛运动是由多个动力蛋白马达的活动产生的，但是每个动力蛋白重链（Dhc）的具体作用在很大程度上是未知的，并且不同Dhc靶向其独特位置的机制也知之甚少。本文报道了衣原体Dhc 1基因的全核苷酸序列和I1内动力蛋白臂1α Dhc的相应推导氨基酸序列，1α Dhc与其他轴丝Dhc相似，但在NH 2-和COOH-末端区域发现了两个额外的磷酸结合基序（P-环）。由于Dhc 1的突变导致运动缺陷和I1内臂的丢失，因此使用一系列Dhc 1转基因来挽救突变表型。回收表达全长或截短的1α Dhcs的活动共转化体。截短的1α Dhc片段缺乏动力蛋白运动域，但仍与1β Dhc和其他I1亚基在正确的轴丝位置组装成部分功能性复合物。对转化体的分析已经确定了I1结构中1α马达结构域的位点，并进一步揭示了1α Dhc在鞭毛运动和趋光行为中的作用。
Flagellar motility is generated by the activity of multiple dynein motors, but the specific role of each dynein heavy chain (Dhc) is largely unknown, and the mechanism by which the different Dhcs are targeted to their unique locations is also poorly understood. We report here the complete nucleotide sequence of the Chlamydomonas Dhc1 gene and the corresponding deduced amino acid sequence of the 1α Dhc of the I1 inner dynein arm. The 1α Dhc is similar to other axonemal Dhcs, but two additional phosphate binding motifs (P-loops) have been identified in the NH2- and COOH-terminal regions. Because mutations in Dhc1 result in motility defects and loss of the I1 inner arm, a series of Dhc1 transgenes were used to rescue the mutant phenotypes. Motile cotransformants that express either full-length or truncated 1α Dhcs were recovered. The truncated 1α Dhc fragments lacked the dynein motor domain, but still assembled with the 1β Dhc and other I1 subunits into partially functional complexes at the correct axoneme location. Analysis of the transformants has identified the site of the 1α motor domain in the I1 structure and further revealed the role of the 1α Dhc in flagellar motility and phototactic behavior.