Wei A, Jegla T, Salkoff L
Department of Anatomy and Neurobiology, Washington University, School of Medicine, Saint Louis, MO 63110, USA.
Neuropharmacology. 1996;35(7):805-29. doi: 10.1016/0028-3908(96)00126-8.
The wealth of accumulating data from the Caenorhabditis elegans genome sequencing project has rapidly accelerated the discovery of novel potassium channel genes and now places within reach the possibility of describing the total complement of potassium channels used by an individual species. Using annotated GenBank sequences, BLAST searches of unfinished sequences and degenerate oligonucleotide polymerase chain reaction (PCR) screens, we have identified and compiled genes for 38 C. elegans potassium channel and two cyclic nucleotide-gated cation channel subunits, representing eight conserved multigene families. Novel families of potassium channel genes were revealed, as well as conserved homologues of all known vertebrate families. Two separate families represent C. elegans homologues for human potassium channels recently implicated in hereditary long QT arrhythmias. Of particular note is an exceptionally large class of at least 23 genes with a novel subunit structure having two tandem 'P' domains; these channels may form as dimers in contrast to all other potassium channel types which form as tetramers. The 40 potassium channel genes are evenly distributed on all six C. elegans chromosomes, with the exception of the instances of gene clustering on the fifth and X chromosomes.
来自秀丽隐杆线虫基因组测序项目积累的数据财富迅速加速了新型钾通道基因的发现，现在已经有可能描述单个物种所使用的钾通道的完整组成。利用注释的GenBank序列、对未完成序列的BLAST搜索以及简并寡核苷酸聚合酶链反应（PCR）筛选，我们已经鉴定并汇编了38个秀丽隐杆线虫钾通道基因和两个环核苷酸门控阳离子通道亚基的基因，它们代表了八个保守的多基因家族。揭示了新的钾通道基因家族以及所有已知脊椎动物家族的保守同源物。两个不同的家族代表了最近与遗传性长QT心律失常有关的人类钾通道的秀丽隐杆线虫同源物。特别值得注意的是一类特别大的至少23个基因，它们具有一种新型亚基结构，有两个串联的“P”结构域；与所有其他形成四聚体的钾通道类型不同，这些通道可能形成二聚体。这40个钾通道基因均匀分布在秀丽隐杆线虫的所有六条染色体上，除了在第五条和X染色体上出现基因簇的情况。
