Genetic control of fusion pore expansion in the epidermis of Caenorhabditis elegans
Genetic control of fusion pore expansion in the epidermis of Caenorhabditis elegans
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DOI：
10.1091/mbc.e06-09-0855
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发表时间：
2007-04-01
影响因子：
3.3
通讯作者：
Podbilewicz, Benjamin
中科院分区：
文献类型：
--
作者：
Gattegno, Tamar;Mittal, Aditya;Podbilewicz, Benjamin
发育细胞融合存在于生殖系、肌肉、骨骼、胎盘和干细胞中。在秀丽隐杆线虫中，300个体细胞在发育过程中融合。虽然关于病毒诱导的膜融合和细胞内膜融合的早期中间产物有广泛的信息，但对膜融合的后期阶段知之甚少。为了剖析线虫胚胎中细胞融合的途径，我们使用了实时共聚焦和电子显微镜的遗传学和动力学分析。我们同时监测发育中胚胎的多细胞融合率，并发现在表皮中膜融合的启动和完成的动态不同阶段。在Eff-1和IDF-1突变体中，细胞融合的各个阶段受到不同程度的阻止或延迟。我们为在不同温度下生长的胚胎生成了动态细胞融合图。同一细胞的不同侧面具有不同的融合性：在胚胎中，左侧和右侧的膜区是不能融合的，而前膜区和后膜区的融合具有自主动力学。除了一个细胞外，所有的细胞对都能形成最大的合胞体。第一次细胞融合不会引发两个方向的有序融合浪潮。超微结构研究表明，表皮合体发生需要Eff-1活性来启动和扩大膜合并。
Developmental cell fusion is found in germlines, muscles, bones, placentae, and stem cells. In Caenorhabditis elegans 300 somatic cells fuse during development. Although there is extensive information on the early intermediates of viralinduced and intracellular membrane fusion, little is known about late stages in membrane fusion. To dissect the pathway of cell fusion in C. elegans embryos, we use genetic and kinetic analyses using live-confocal and electron microscopy. We simultaneously monitor the rates of multiple cell fusions in developing embryos and find kinetically distinct stages of initiation and completion of membrane fusion in the epidermis. The stages of cell fusion are differentially blocked or retarded in eff-1 and idf-1 mutants. We generate kinetic cell fusion maps for embryos grown at different temperatures. Different sides of the same cell differ in their fusogenicity: the left and right membrane domains are fusion-incompetent, whereas the anterior and posterior membrane domains fuse with autonomous kinetics in embryos. All but one cell pair can initiate the formation of the largest syncytium. The first cell fusion does not trigger a wave of orderly fusions in either direction. Ultrastructural studies show that epidermal syncytiogenesis require eff-1 activities to initiate and expand membrane merger.