Ortells M O, Lunt G G
School of Biology and Biochemistry, University of Bath, UK.
Trends Neurosci. 1995 Mar;18(3):121-7. doi: 10.1016/0166-2236(95)93887-4.
The fast-acting ligand-gated ion channels (LGICs) constitute a group that encompasses nicotinic ACh, 5-HT3, GABAA and glycine receptors. Undoubtedly, they all share a common evolutionary ancestor, and the group can therefore be considered to be a gene superfamily. Because the members of the superfamily are all receptors, it is reasonable to suppose that their common ancestor must also have been some type of receptor, and because the receptors are made of similar subunits, the ancestor was probably homo-oligomeric. Although we failed to find a group of proteins that are related evolutionarily to this superfamily, the analysis of the evolutionary relationships within the superfamily is possible and can give rise to information about the evolution of the structure and function of present-day receptors and indeed of the nervous system itself.
快速作用的配体门控离子通道（LGICs）构成了一个包含烟碱型乙酰胆碱受体、5-羟色胺3型受体、γ-氨基丁酸A型受体和甘氨酸受体的群体。毫无疑问，它们都有着共同的进化祖先，因此这个群体可被视为一个基因超家族。由于该超家族的成员均为受体，所以合理推测其共同祖先也必定是某种类型的受体，并且由于这些受体由相似的亚基组成，其祖先可能是同型寡聚体。尽管我们未能找到与这个超家族在进化上相关的一组蛋白质，但对该超家族内部进化关系的分析是可行的，并且能够产生有关当今受体结构和功能进化的信息，实际上也能产生有关神经系统本身进化的信息。
