Assembly of body wall muscle and muscle cell attachment structures in Caenorhabditis elegans.
Assembly of body wall muscle and muscle cell attachment structures in Caenorhabditis elegans.
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DOI：
10.1083/jcb.124.4.491
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发表时间：
1994-02
期刊：
影响因子：
--
通讯作者：
Waterston RH
中科院分区：
文献类型：
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作者：
Hresko MC;Williams BD;Waterston RH
C. 线虫有四个用于运动的肌肉象限。收缩转化为运动，因为肌肉细胞通过皮下组织中的特殊基底膜和半桥粒结构（覆盖蠕虫并分泌角质层的细胞合胞体）固定在角质层（蠕虫的外部覆盖物）上。为了研究肌肉组装，我们使用抗体来确定野生型和突变型秀丽隐杆线虫胚胎中肌肉和附着结构成分的空间和时间分布。首先观察到肌原纤维成分弥散分布在肌肉细胞中，并在一些分裂细胞中表达。随后，这些成分在皮下组织附近的膜上积聚，肌节将在此处形成，表明细胞已极化。肌肉附着结构的组装在空间和时间上与肌肉组装协调，这表明重要的发育信号可能在肌肉和皮下细胞之间传递。对影响肌肉组装的纯合突变胚胎的分析表明，比受影响的蛋白质更靠近膜的肌肉成分组装得很好，而距离膜较远的肌肉成分却不能。我们的结果提出了一个模型，其中晶格组装是在膜上启动的，肌肉结构元件的空间组织是由膜近端事件决定的，而不是由细丝成分本身决定的。
C. Elegans has four muscle quadrants that are used for locomotion. Contraction is converted to locomotion because muscle cells are anchored to the cuticle (the outer covering of the worm) by a specialized basement membrane and hemidesmosome structures in the hypodermis (a cellular syncytium that covers the worm and secretes the cuticle). To study muscle assembly, we have used antibodies to determine the spatial and temporal distribution of muscle and attachment structure components in wild-type and mutant C. elegans embryos. Myofibrillar components are first observed diffusely distributed in the muscle cells, and are expressed in some dividing cells. Later, the components accumulate at the membrane adjacent to the hypodermis where the sarcomeres will form, showing that the cells have become polarized. Assembly of muscle attachment structures is spatially and temporally coordinated with muscle assembly suggesting that important developmental signals may be passed between muscle and hypodermal cells. Analysis of embryos homozygous for mutations that affect muscle assembly show that muscle components closer to the membrane than the affected protein assemble quite well, while those further from the membrane do not. Our results suggest a model where lattice assembly is initiated at the membrane and the spatial organization of the structural elements of the muscle is dictated by membrane proximal events, not by the filament components themselves.