Ca2+ signalling is not required for chemotaxis in Dictyostelium
Ca2+ signalling is not required for chemotaxis in Dictyostelium
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DOI：
10.1093/emboj/19.17.4846
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发表时间：
2000-09-01
期刊：
影响因子：
11.4
通讯作者：
Kay, RR
中科院分区：
文献类型：
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作者：
Traynor, D;Milne, JLS;Kay, RR
网骨藻细胞可以快速地向环AMP（cAMP）的来源移动，这种化学引诱物被G蛋白连接的受体检测到，其触发包括Ca 2+的快速流入的信号级联。我们已经破坏了肌醇1，4，5-三磷酸（InsP（3））受体样基因iplA，以产生无效细胞，其中响应于化学引诱物的Ca 2+内流被消除，就像趋化刺激后游离胞质Ca 2+（[Ca 2 +]（c））的正常增加一样。然而，静息[Ca 2 +]（c）与野生型相似。该突变体为Ca ~（2+）内流在趋化性和控制趋化性的信号级联中的作用提供了一个试验。肌动蛋白向细胞骨架中的移动也遵循与野生型相似的动力学，突变体细胞对cAMP或叶酸的趋化作用有效，它们对cAMP的敏感性与野生型相似。最后，它们以与野生型细胞相似的速度移动，有或没有趋化剂。我们得出结论，Ca 2+信号传导对于cAMP的趋化作用不是必需的。
Dictyostelium cells can move rapidly towards a source of cyclic-AMP (cAMP), This chemoattractant is detected by G-protein-linked receptors, which trigger a signalling cascade including a rapid influx of Ca2+. We have disrupted an inositol 1,4,5-trisphosphate (InsP(3)) receptor-like gene, iplA, to produce null cells in which Ca2+ entry in response to chemoattractants is abolished, as is the normal increase in free cytosolic Ca2+ ([Ca2+](c)) that follows chemotactic stimulation. However, the resting [Ca2+](c) is similar to wild type. This mutant provides a test for the role of Ca2+ influx in both chemotaxis and the signalling cascade that controls it. The production of cyclic-GMP and cAMP, and the activation of the MAP kinase, DdERK2, triggered from the cAMP receptor, are little perturbed in the mutant; mobilization of actin into the cytoskeleton also follows similar kinetics to wild type, Mutant cells chemotax efficiently towards cAMP or folic acid and their sensitivity to cAMP is similar to wild type, Finally, they move at similar speeds to wild-type cells, with or without chemoattractant, We conclude that Ca2+ signalling is not necessary for chemotaxis to cAMP.