果蝇程序化死亡基因5(PDCD5)同源cDNA的克隆和序列分析

Cloning and Sequencing of a Drosophila cDNA Homologous to Programmed Cell Death 5 (PDCD5) Gene

为了解人类白血病细胞凋亡相关新基因 TFAR1 9(PDCD5,programmed cell death5)在不同种属间的序列同源性 ,利用 EST(expression sequence tag)拼接、RT- PCR、DNA序列测定技术及计算机分析技术 ,首次成功地进行了果蝇 PDCD5同源 c DNA编码区基因克隆和序列分析 .发现果蝇与小鼠及果蝇与人 PDCD5在核苷酸水平上分别有 57.5%和 57.1 %的同源性 ,在氨基酸水平上分别有 46.8%和 46.4%的同源性 .功能区分析发现 ,果蝇 PDCD5c DNA编码 1 33个氨基酸 ,计算机预测可能是一种核蛋白 ,含 5个可能的酪蛋白激酶 (casein kinase )磷酸化位点 ,2个可能的 PKC磷酸化位点 ,与人 PDCD5的功能区类似 .因而果蝇 PDCD5是与人 PDCD5同源的新基因 ,可能都与细胞程序化死亡相关 .

To find out the sequence homology of a novel gene TFAR 19 (TF 1 cell apoptosis related gene 19,now named programmed cell death 5, PDCD 5) between different species,the EST (expression sequence tag) sequence alignment method,RT PCR,DNA sequencing,and computer analysis were used for the cDNA cloning.The coding region of Drosophila PDCD 5 homologous cDNA was successfully cloned and sequenced.It was found that there was 57.5% and 57.1% homology at the nucleotide level,and 46.8% and 46.4% homology at the amino acid level,respectively,between Drosophila and mouse,and Drosophila and human PDCD 5 cDNA.The sequence reveals an open reading frame encoding 133 amino acids,five potential casein kinase Ⅱ and two potential protein kinase C phosphorylation sites.It was possible that Drosophila PDCD5 was a nuclear protein,similarly with human PDCD5.Therefore,the Drosophila PDCD 5 is a homolog of human PDCD 5 and may have functional relationship with programmed cell death.