人类SR蛋白超家族新成员——SFRS12(SRrp508)的基因克隆和特性分析  

Molecular Cloning, Characterization, Chromosomal Assignment, Genomic Organization and Verification of SFRS12(SRrp508),a Novel Member of Human SR Protein Superfamily and a Human Homolog of Rat SRrp86

作　　者：张德礼[1] 孙晓静[1] 凌伦奖[2] 陈润生[2] 马大龙[1] 

机构地区：[1]北京大学人类疾病基因研究中心,国家人类基因组北方研究中心,北京100083 [2]中国科学院生物物理研究所,北京100101

出　　处：《Acta Genetica Sinica》2002年第5期377-383,共7页

基　　金：中国博士后科学基金资助项目 (资助号 :2 92 0 0 112 1760 80 62 0 0 0 ) ~~

摘　　要：采用生物信息学方法克隆出全长 3811bp的人类RC5 0 8cDNA片段 ,经核酸和蛋白质分析为人类新基因 (Gen Bank登记号 :AF4 5 90 94 ) ,利用RT PCR方法从人类胰脏组织中扩增出包含编码 5 0 8个氨基酸残基最大开放读码框架 (ORF)的 16 80bpcDNA片段 ,经核酸测序证明与电子克隆结果完全一致。该基因具有启动子和TATA box,ORF前同一相位有多个终子码 ,后有加尾信号 ,显示为客观存在基因。该基因含有 12个外显子 (96～ 2 0 93bp)和 11个内含子 (14 0～ 5 15 3bp) ,定位于人类 5号染色体 5q11.2～q12 .1,无任何连锁基因存在。该基因ORF 342～ 186 8(15 2 7)横跨10个外显子 ,所编码 5 0 8氨基酸蛋白的全长序列与大鼠丝氨酸 精氨酸二肽富含性 (SR)剪切调控蛋白 86 (SRrp86 )高度同源 ,在核酸和蛋白水平的同源性分别为 84 %和 86 % ,与其他已知蛋白无论在核酸水平还是在氨基酸水平几乎均无整体的同源性。结果表明 ,所克隆的 5 0 8氨基酸蛋白才是大鼠SRrp86的人类同源物 ,从而修正了Barnard(2 0 0 0 )所指出的人类同源物为人类精氨酸富含性核蛋白 5 4 (p5 4 )这一论断 ,并提示它是日益增长的SR蛋白超家族的又一个新成员。该基因组织表达谱广泛 ,有可能具有转录因子活性 ,暂命名为SR相关剪切调控蛋白 5 0 8(SRrp5 0We have identified and characterized a novel human serine arginine rich (SR) splicing regulatory protein 508 (SRrp508) gene that is related to other members of the growing SR superfamily, but only homologous to rat (Rattus norvegicus) serine arginine rich splicing regulatory protein 86 (SRrp86) gene. The full length cDNA of 3811bp for human SRrp508 was cloned through a blast search of public databases following the identification of a cDNA contig of 658bp obtained by EST assembly with full robotization in supercomputer in large scale. Structurally, human SRrp508 encodes a polypeptide of 508 amino acids, which contains a single amino terminal RNA recognition motif (RRM) and two carboxy terminal domains rich in serine arginine dipeptides that are highly conserved among other members of the SR superfamily. The conserved SR and RRM domains emphasize the biological importance of this gene. The SRrp508 gene, which contains 12 exons ranging from 0.096 to 2.093 kb and 11 introns ranging from 0.14 to 5.153 kb, is mapped to the human cytogenetic region 5q11.2～q12.1 using the bioinformatic analysis, and it does not link to any other genes. Furthermore, we have experimentally cloned and sequenced a cDNA fragment of 1680bp containing the full length ORF of 1527bp in this novel human gene by RT PCR from the single stranded human pancreas cDNA library (Clontech), which is fully identical with that of the in silico cloning determined by the nucleotide sequencing. Thus, we in silico cloned this gene with GenBank accession number of AF459094 identified solely by bioinformatic analysis of the nucleotide and protein. This novel gene has promotors, TATA box, several stop codons in the upstream of ORF, and PolyA signal in the downstream of ORF. Based on the above results, it can be concluded that we have obtained a complete novel human gene. The gene sequence exhibits good overall homology to that of rat SRrp86 gene, with 84% and 86% identity over the full length nucleotide and protein, respectively, and with 96% a

关 键 词：人类SR蛋白超家族 SRrp508 基因克隆 特性分析 

分 类 号：Q986[生物学—人类学]