Imboden M, Devignot V, Korn H, Goblet C
Laboratoire de Biologie Cellulaire et Moléculaire du Neurone, INSERM U261, Institut Pasteur, 25, Rue du Dr Roux, F-75724, Paris Cedex 15, France.
Neuroscience. 2001;103(3):811-30. doi: 10.1016/s0306-4522(00)00576-5.
We report the cloning of the zebrafish beta subunit of the glycine receptor and compare the anatomical distribution of three glycine receptor subunit constituents in adult zebrafish brain (alphaZ1, alphaZ2 and betaZ) to the expression pattern of homologous receptor subunits (alpha1, alpha2 and beta) in the mammalian adult CNS. Non-radioactive hybridization was used to map the distribution of the alphaZ1, alphaZ2 and betaZ glycine receptor subunit messenger RNAs in the adult zebrafish brain. The anterior-posterior expression gradient found in adult zebrafish brain was similar to that reported in mammalian CNS. However, the glycine receptor transcripts, notably the alphaZ1 subunit, were more widely distributed in the anterior regions of the zebrafish than in the adult mammalian brain. The isoform-specific distribution pattern was less regionalized in zebrafish than in the rat mammalian CNS. Nevertheless, there was some regionalization of alphaZ1, alphaZ2 and betaZ transcripts in the diencephalic and mesencephalic nuclei where different sensory and motor centers express either alphaZ1/betaZ or alphaZ2 subunits. In contrast to the widespread distribution of the beta subunit in adult mammalian brain, alphaZ2 messenger RNA presented the widest expression territory of all three glycine receptor subunits tested. alphaZ2 messenger RNA was expressed in the absence of alphaZ1 and betaZ messenger RNA in the outer nuclear layer of the retina, the inferior olive and the raphe of the medulla oblongata, as well as in the nucleus of Cajal of the medulla spinalis. In contrast, an identified central neuron of the reticular formation, the Mauthner cell, expresses all three glycine receptor subunits (alphaZ1, alphaZ2 and betaZ). This report extends the already described glycine receptor expression in the vertebrate CNS and confirms the importance of glycine-mediated inhibition in spinal cord and brainstem.
我们报道了斑马鱼甘氨酸受体β亚基的克隆，并比较了成年斑马鱼脑中三种甘氨酸受体亚基成分（αZ1、αZ2和βZ）的解剖分布与成年哺乳动物中枢神经系统中同源受体亚基（α1、α2和β）的表达模式。使用非放射性杂交来定位成年斑马鱼脑中αZ1、αZ2和βZ甘氨酸受体亚基信使核糖核酸的分布。在成年斑马鱼脑中发现的前后表达梯度与哺乳动物中枢神经系统中报道的相似。然而，甘氨酸受体转录本，尤其是αZ1亚基，在斑马鱼前部区域的分布比成年哺乳动物脑更广泛。在斑马鱼中，亚型特异性分布模式比大鼠哺乳动物中枢神经系统中的区域化程度更低。尽管如此，在间脑和中脑核中，αZ1、αZ2和βZ转录本存在一定的区域化，不同的感觉和运动中枢表达αZ1/βZ或αZ2亚基。与成年哺乳动物脑中β亚基的广泛分布相反，αZ2信使核糖核酸在所测试的所有三种甘氨酸受体亚基中呈现出最广泛的表达区域。αZ2信使核糖核酸在视网膜外核层、下橄榄核和延髓缝际核中，以及脊髓的 Cajal 核中，在没有αZ1和βZ信使核糖核酸的情况下表达。相反，网状结构中一个已确定的中枢神经元，即莫纳细胞，表达所有三种甘氨酸受体亚基（αZ1、αZ2和βZ）。本报告扩展了脊椎动物中枢神经系统中已描述的甘氨酸受体表达，并证实了甘氨酸介导的抑制在脊髓和脑干中的重要性。
