Piirsoo Marko, Meijer Dies, Timmusk Tõnis
Department of Gene Technology, Tallinn University of Technology, Akadeemia tee 15, Tallinn 19086, Estonia.
BMC Dev Biol. 2009 Feb 11;9:10. doi: 10.1186/1471-213X-9-10.
Members of the calcium-activated chloride channel (CLCA) gene family have been suggested to possess a variety of functions including cell adhesion and tumor suppression. Expression of CLCA family members has mostly been analyzed in non-neural tissues. Here we describe the expression of mouse and human CLCA genes in the nervous system.
We show that from the six mouse CLCA family members only Clca1, Clca2 and Clca4 mRNAs are expressed in the adult brain, predominantly in olfactory ensheathing cells. During mouse nervous system development Clca1/2 is more widely expressed, particularly in cranial nerves, the diencephalon and in the cerebral cortex. While human CLCA2 and CLCA4 genes are widely expressed in brain, and at particularly high levels in the optic nerve, human CLCA3, the closest homologue of mouse Clca1, Clca2 and Clca4, is not expressed in the brain. Furthermore, we characterize the expression pattern of mouse Clca1/2 genes during embryonic development by in situ hybridization.
The data published in this article indicate that within the nervous system mouse Clca1/2 genes are highly expressed in the cells ensheathing cranial nerves. Human CLCA2 and CLCA4 mRNAs are expressed at high level in optic nerve. High level expression of CLCA family members in mouse and human glial cells ensheathing nerves suggests a specific role for CLCA proteins in the development and homeostasis of these cells.
钙激活氯离子通道（CLCA）基因家族成员被认为具有多种功能，包括细胞黏附和肿瘤抑制。CLCA家族成员的表达大多在非神经组织中进行分析。在此，我们描述小鼠和人类CLCA基因在神经系统中的表达情况。
我们发现，在六个小鼠CLCA家族成员中，只有Clca1、Clca2和Clca4的mRNA在成年大脑中表达，主要表达于嗅鞘细胞。在小鼠神经系统发育过程中，Clca1/2的表达更为广泛，尤其在脑神经、间脑和大脑皮层中。虽然人类CLCA2和CLCA4基因在大脑中广泛表达，且在视神经中表达水平特别高，但人类CLCA3，即小鼠Clca1、Clca2和Clca4的最接近同源物，在大脑中不表达。此外，我们通过原位杂交对小鼠Clca1/2基因在胚胎发育过程中的表达模式进行了表征。
本文发表的数据表明，在神经系统中，小鼠Clca1/2基因在包裹脑神经的细胞中高度表达。人类CLCA2和CLCA4的mRNA在视神经中高水平表达。CLCA家族成员在小鼠和人类包裹神经的胶质细胞中的高水平表达表明CLCA蛋白在这些细胞的发育和稳态中具有特定作用。
