HPCL2基因表达的选择性剪切分析

Expression Regulation Analysis of HPCL2 Gene by In silica Alternative Spli cing

2 羟基植烷酸辅酶A裂解酶 (2 hydroxypanthyl CoAlyase ,HPCL2 )是 3 甲基脂肪酸α 氧化途径中的关键酶 .采用鸟枪法测序技术 ,得到了HPCL2基因的基因组序列 .结果显示 ,HPCL2基因组大小为 40 82 9bp ,共有 17个外显子 ,16个内含子 .外显子平均大小为 116bp ,内含子平均大小为 2 42 9bp ,属于结构紧凑基因 .从dbEST数据库中筛选与HPCL2基因的mRNA (GenBankAcc .:AJ13 1753 )相互重叠表达序列标签 (EST)共有2 13个 ,分别来自 2 9个不同的组织 .将EST与基因组序列进行Blast分析 ,共检测 17个EST具有选择性剪切 ,其中 14例属外显子遗漏 (exonskipping) ,2例外显子增加 (exoninclusion)和 1例剪切位点改变 (splicingsiteshift) .外显子遗漏主要发生在 5′端的第 3到第 8个外显子 .结果表明 。

In the third step of the alpha-oxidation of 3-methyl-branched fatty acids such as phytanic acid, a 2-hydroxy3-methylacyl-CoA is cleaved into formyl-CoA and a 2-methyl-branched fatty aldehyde, which is regulated by 2-hydroxypanthyl-CoA lyase HPCL2. Using shot-gun sequencing technique, the genome sequence of the gene ( HPCL2) code for the lyase was obtained. The gene is 40 829 bp in genome size including 17 exons and 16 introns, with an average 116 bp in exon size and 2 429 bp in intron size. The different transcriptional isoforms were also investigated by using method of alternative splicing in silica. In order to investigate the level of alternative splicing and to search for novel splice variants, total 213 ESTs derived from 29 different tissues were collected and aligned against the genome sequence of the gene. 17 ESTs were found having different splicing type that could be classified into three types of alternative splicing. 14 of the ESTs were detected to have exon skipping, 2 intron not spliced and 1 splice site shift. The data suggested that exon skipping was possibly one of the major mechanisms of transcription regulation of HPCL2 gene.