Fisher P R, Noegel A A, Fechheimer M, Rivero F, Prassler J, Gerisch G
School of Microbiology, La Trobe University, Bundoora, Victoria, Australia.
Curr Biol. 1997 Nov 1;7(11):889-92. doi: 10.1016/s0960-9822(06)00379-4.
Chemotactic aggregation of starving amoebae of Dictyostelium discoideum leads to formation of a motile, multicellular organism - the slug - whose anterior tip controls its phototactic and thermotactic behaviour. To determine whether proteins that regulate the in vitro assembly of actin are involved in these responses, we tested phototaxis and thermotaxis in mutant slugs in which the gene encoding one of five actin-binding proteins had been disrupted. Of the proteins tested - severin, alpha-actinin, fimbrin, the 34 kD actin-bundling protein and the F-actin cross-linking gelation factor (ABP-120) - only ABP-120 proved essential for normal phototaxis and thermotaxis in the multicellular slugs. The related human protein ABP-280 is required for protein phosphorylation cascades initiated by lysophosphatidic acid and tumor necrosis factor alpha. The repeating segments constituting the rod domains of ABP-120 and ABP-280 may be crucial for the function of both proteins in specific signal transduction pathways by mediating interactions with regulatory proteins.
盘基网柄菌饥饿变形虫的趋化聚集导致形成一种能运动的多细胞生物体——蛞蝓体，其前端控制着它的趋光性和趋热性。为了确定调节肌动蛋白体外组装的蛋白质是否参与这些反应，我们在编码五种肌动蛋白结合蛋白之一的基因被破坏的突变蛞蝓体中测试了趋光性和趋热性。在所测试的蛋白质中——肌动蛋白切断蛋白、α - 辅肌动蛋白、丝束蛋白、34kD肌动蛋白成束蛋白和F - 肌动蛋白交联凝胶化因子（ABP - 120）——只有ABP - 120被证明对于多细胞蛞蝓体的正常趋光性和趋热性至关重要。相关的人类蛋白ABP - 280是由溶血磷脂酸和肿瘤坏死因子α引发的蛋白质磷酸化级联反应所必需的。构成ABP - 120和ABP - 280杆状结构域的重复片段可能通过介导与调节蛋白的相互作用，对这两种蛋白质在特定信号转导途径中的功能至关重要。
