Ogura K, Wicky C, Magnenat L, Tobler H, Mori I, Müller F, Ohshima Y
Department of Biology, Faculty of Science, Kyushu University, Fukuoka, Japan.
Genes Dev. 1994 Oct 15;8(20):2389-400. doi: 10.1101/gad.8.20.2389.
Mutations in the unc-51 gene of the nematode Caenorhabditis elegans result in various abnormalities in axonal elongation and axonal structures. We cloned the unc-51 gene by tagging with the transposon Tc1. The wild-type unc-51 gene, which rescued the mutant phenotypes, encodes a novel serine/threonine kinase of 856 amino acids. Mutation sites were identified in the unc-51 gene of six mutants. A Lys-->Met mutation created in vitro in the kinase domain led to the loss of rescuing activity and was dominant negative, indicating that the kinase domain of Unc-51 is essential for the function. Expression of an unc-51/lacZ fusion gene was observed in many neurons at all stages. We propose that protein phosphorylation by the unc-51 product is important for axonal elongation and possibly for axonal guidance.
线虫秀丽隐杆线虫unc-51基因的突变会导致轴突伸长和轴突结构出现各种异常。我们通过用转座子Tc1进行标记克隆了unc-51基因。能挽救突变体表型的野生型unc-51基因编码一种含856个氨基酸的新型丝氨酸/苏氨酸激酶。在六个突变体的unc-51基因中鉴定出了突变位点。在激酶结构域中体外产生的赖氨酸到甲硫氨酸的突变导致挽救活性丧失，并且是显性负性的，这表明Unc-51的激酶结构域对其功能至关重要。在所有阶段的许多神经元中都观察到了unc-51/lacZ融合基因的表达。我们提出，unc-51产物的蛋白质磷酸化对于轴突伸长以及可能对于轴突导向很重要。
