Mammalian homologue of the Caenorhabditis elegans UNC-76 protein involved in axonal outgrowth is a protein kinase C zeta-interacting protein.
Mammalian homologue of the Caenorhabditis elegans UNC-76 protein involved in axonal outgrowth is a protein kinase C zeta-interacting protein.
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秀丽隐杆线虫的哺乳动物同源物UNC-76参与轴突生长的蛋白是一种蛋白激酶C Zeta相互作用蛋白。
DOI：
10.1083/jcb.144.3.403
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发表时间：
1999-02-08
影响因子：
7.8
通讯作者：
Tanizawa, K
中科院分区：
文献类型：
--
作者：
Kuroda, S;Nakagawa, N;Tokunaga, C;Tatematsu, K;Tanizawa, K
通过以蛋白激酶C z (PKC z)的调节结构域为诱饵，对大鼠脑cDNA文库进行酵母双杂交筛选，我们克隆了编码新型PKC z相互作用蛋白的基因，该蛋白与参与轴突生长和成束的秀丽隐杆线虫UNC-76蛋白同源。名为 FEZ1（成束和延伸蛋白 zeta-1）的蛋白质由 393 个氨基酸残基组成，显示出高天冬氨酸/谷氨酸含量，并包含多个预计形成两亲性螺旋的区域。 Northern 印迹分析表明，FEZ1 mRNA 在成年大鼠大脑和小鼠胚胎的整个发育阶段大量表达。通过对 PKC 的各种缺失突变体进行酵母双杂交测定，结果显示 FEZ1 与 PKC z 的 NH2 末端可变区 (V1) 相互作用，而与 PKCε 的 NH2 末端可变区 (V1) 相互作用较弱。在共表达 FEZ1 和 PKC z 的 COS-7 细胞中，FEZ1 主要存在于质膜中，与 PKC z 结合并被磷酸化。这些结果表明 FEZ1 是 PKC z 的新型底物。当使用 PKC z 的组成型活性突变体时，在 COS-7 细胞的细胞质中发现了 FEZ1。用 PKC 抑制剂星形孢菌素处理细胞后，FEZ1 从细胞质易位到质膜，表明 FEZ1 的细胞质易位直接受 PKC z 活性调节。虽然单独表达 FEZ1 对 PC12 细胞没有影响，但 FEZ1 和组成型活性 PKC z 的共表达刺激了 PC12 细胞的神经元分化。结合最近的发现，即人类 FEZ1 蛋白能够补充线虫轴突束内正常轴突成束和伸长所必需的 UNC-76 功能，这些结果表明 FEZ1 通过与 PKC z 相互作用，在哺乳动物的轴突引导机制中发挥着至关重要的作用。
By the yeast two-hybrid screening of a rat brain cDNA library with the regulatory domain of protein kinase C ζ (PKCζ) as a bait, we have cloned a gene coding for a novel PKCζ-interacting protein homologous to the Caenorhabditis elegans UNC-76 protein involved in axonal outgrowth and fasciculation. The protein designated FEZ1 (fasciculation and elongation protein zeta-1) consisting of 393 amino acid residues shows a high Asp/Glu content and contains several regions predicted to form amphipathic helices. Northern blot analysis has revealed that FEZ1 mRNA is abundantly expressed in adult rat brain and throughout the developmental stages of mouse embryo. By the yeast two-hybrid assay with various deletion mutants of PKC, FEZ1 was shown to interact with the NH2-terminal variable region (V1) of PKCζ and weakly with that of PKCε. In the COS-7 cells coexpressing FEZ1 and PKCζ, FEZ1 was present mainly in the plasma membrane, associating with PKCζ and being phosphorylated. These results indicate that FEZ1 is a novel substrate of PKCζ. When the constitutively active mutant of PKCζ was used, FEZ1 was found in the cytoplasm of COS-7 cells. Upon treatment of the cells with a PKC inhibitor, staurosporin, FEZ1 was translocated from the cytoplasm to the plasma membrane, suggesting that the cytoplasmic translocation of FEZ1 is directly regulated by the PKCζ activity. Although expression of FEZ1 alone had no effect on PC12 cells, coexpression of FEZ1 and constitutively active PKCζ stimulated the neuronal differentiation of PC12 cells. Combined with the recent finding that a human FEZ1 protein is able to complement the function of UNC-76 necessary for normal axonal bundling and elongation within axon bundles in the nematode, these results suggest that FEZ1 plays a crucial role in the axon guidance machinery in mammals by interacting with PKCζ.