Kikuchi K, Chédotal A, Hanafusa H, Ujimasa Y, de Castro F, Goodman C S, Kimura T
Sumitomo Pharmaceuticals Research Center, 3-1-98, Kasugade-Naka, Konohana, Osaka, 554-0022, Japan.
Mol Cell Neurosci. 1999 Jan;13(1):9-23. doi: 10.1006/mcne.1998.0732.
Semaphorins comprise a large family of proteins implicated in axonal guidance. We cloned a novel transmembrane semaphorin, semaphorin Y (Sema Y), which has a class VI sema domain. Sema Y shows growth cone collapsing activity on DRG neurons in vitro, and the target regions of the DRG neurons express sema Y mRNA during development. Sema Y may be a stop signal for these neurons in their target areas. Interestingly, sema Y mRNA was also detected in other neurons and their targets. Two isoforms of Sema Y derived from alternative splicing were identified and their expression was found to be regulated in a tissue- and age-dependent manner. Distribution of sema Y mRNA suggests that Sema Y might also be important during maintenance of axonal connections and/or differentiation and migration of cells. Sequence comparison among class VI semaphorins revealed two short conserved sequence stretches in their cytoplasmic domains, suggesting interaction of these semaphorins with a common intracellular component(s).
信号素构成了一个与轴突导向有关的蛋白质大家族。我们克隆了一种新型跨膜信号素，信号素Y（Sema Y），它具有VI类信号域。Sema Y在体外对背根神经节（DRG）神经元表现出生长锥塌陷活性，并且DRG神经元的靶区域在发育过程中表达sema Y mRNA。Sema Y可能是这些神经元在其靶区域的一个停止信号。有趣的是，在其他神经元及其靶标中也检测到了sema Y mRNA。鉴定出了源自可变剪接的Sema Y的两种异构体，并且发现它们的表达以组织和年龄依赖性方式受到调节。sema Y mRNA的分布表明Sema Y在轴突连接的维持和/或细胞的分化与迁移过程中可能也很重要。VI类信号素之间的序列比较揭示了它们胞质结构域中有两个短的保守序列片段，表明这些信号素与一种共同的细胞内成分相互作用。
