Conditional dominant mutations in the Caenorhabditis elegans gene act-2 identify cytoplasmic and muscle roles for a redundant actin isoform.
Conditional dominant mutations in the Caenorhabditis elegans gene act-2 identify cytoplasmic and muscle roles for a redundant actin isoform.
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秀丽隐杆线虫基因 act-2 的条件显性突变可识别冗余肌动蛋白亚型的细胞质和肌肉作用。
DOI：
10.1091/mbc.e05-09-0886
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发表时间：
2006
影响因子：
3.3
通讯作者：
Bowerman,Bruce
中科院分区：
文献类型：
--
作者：
Willis,JohnH;Munro,Edwin;Lyczak,Rebecca;Bowerman,Bruce
每个动物基因组编码多种高度保守的肌动蛋白异构体，这些肌动蛋白异构体形成微丝细胞骨架。先前对脊椎动物和无脊椎动物的研究表明，许多肌动蛋白亚型仅限于非肌肉（细胞质）功能或肌细胞中肌原纤维力的产生。我们已经确定了两个温度敏感和半显性胚胎致死的秀丽隐杆线虫，每个都有一个错义突变inact-2，五个C之一。编码肌动蛋白亚型的优雅基因。这些突变改变保守的和相邻的氨基酸预测形成的ATP结合口袋的肌动蛋白的一部分。在限制性温度下，这两种突变导致与异常和引人注目的膜侵入和突起相关的皮质微丝的异常分布。与这些显性错义突变引起的缺陷相反，anact-2缺失并不导致早期胚胎细胞分裂缺陷，这表明涉及额外的和多余的肌动蛋白亚型。因此，我们发现，在早期胚胎细胞中，两种额外的肌动蛋白亚型act-1和act-3与act-2是细胞质功能所必需的。act-1和act-3基因以前也与肌肉功能有关。我们发现ACT-2：：GFP报告基因在胚胎细胞中以细胞质形式表达，并且也掺入成人肌肉细胞的收缩丝中。此外，其中一个dominantact-2突变导致不协调的成年运动。我们得出结论，冗余C。elegansactin同种型在肌肉和非肌肉收缩过程中都起作用。
Animal genomes each encode multiple highly conserved actin isoforms that polymerize to form the microfilament cytoskeleton. Previous studies of vertebrates and invertebrates have shown that many actin isoforms are restricted to either nonmuscle (cytoplasmic) functions, or to myofibril force generation in muscle cells. We have identified two temperature-sensitive and semidominant embryonic-lethalCaenorhabditis elegansmutants, each with a single mis-sense mutation inact-2,one of fiveC. elegansgenes that encode actin isoforms. These mutations alter conserved and adjacent amino acids predicted to form part of the ATP binding pocket of actin. At the restrictive temperature, both mutations resulted in aberrant distributions of cortical microfilaments associated with abnormal and striking membrane ingressions and protrusions. In contrast to the defects caused by these dominant mis-sense mutations, anact-2deletion did not result in early embryonic cell division defects, suggesting that additional and redundant actin isoforms are involved. Accordingly, we found that two additional actin isoforms,act-1andact-3,were required redundantly withact-2for cytoplasmic function in early embryonic cells. Theact-1and-3genes also have been implicated previously in muscle function. We found that an ACT-2::GFP reporter was expressed cytoplasmically in embryonic cells and also was incorporated into contractile filaments in adult muscle cells. Furthermore, one of the dominantact-2mutations resulted in uncoordinated adult movement. We conclude that redundantC. elegansactin isoforms function in both muscle and nonmuscle contractile processes.
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影响因子：
3.3
作者：
Kovar, DR;Wu, JQ;Pollard, TD
通讯作者：
Pollard, TD
DOI：
10.1083/jcb.146.2.439
发表时间：
1999-07-26
期刊：
The Journal of cell biology
影响因子：
--
作者：
Shelton CA;Carter JC;Ellis GC;Bowerman B
通讯作者：
Bowerman B
影响因子：
9.2
作者：
Severson, AF;Baillie, DL;Bowerman, B
通讯作者：
Bowerman, B
影响因子：
4.6
作者：
W. G. Kelly;A. Fire
通讯作者：
W. G. Kelly;A. Fire
β-微管蛋白的突变破坏了早期秀丽隐杆线虫胚胎中的纺锤体方向和微管动力学。
影响因子：
3.3
作者：
Amanda Wright;C. Hunter
通讯作者：
C. Hunter