猪ADAR2基因全长cDNA克隆、序列特征及表达模式分析

旨在克隆猪作用于RNA的腺苷脱氨酶2基因（ADAR2）全长cDNA序列，同时对该基因在猪不同组织中的表达规律进行探索。利用RACE （rapid-amplification of cDNA ends）对大白猪ADAR2基因mRNA全长序列进行克隆，并进行生物信息学分析；用荧光定量PCR方法检测35日龄大白猪心、肝、肺、肾、脾、脑、小肠、背最长肌和背部脂肪9种组织中ADAR2的表达水平。结果表明，猪ADAR2基因cDNA全长6 305 bp，共包含12个外显子，编码704个氨基酸，与人、黑猩猩、猕猴、长臂猿、黄牛、山羊和绵羊的CDS区核酸序列和氨基酸序列的一致性均在84%以上。该基因编码的蛋白含有2个双链RNA结合基序和一个脱氨酶结构域。猪ADAR2在检测的各组织中均表达，其中在肺中的表达量最高。综上所述，本研究成功克隆了猪ADAR2基因全长cDNA序列，并且发现其在猪体内广泛表达，为深入研究ADAR2的功能奠定了良好的基础。

The Full-length cDNA Cloning,Sequence Characterization and Expression Pattern Analysis of Porcine ADAR2 Gene

This study aimed to clone the full-length cDNA of the porcine ADAR2 gene and explore its expression pattern in different tissues of pigs.Rapid-amplification of cDNA ends(RACE)was used to clone the full-length cDNA sequence of the ADAR2 gene in Large White pigs and the sequence was analyzed by bioinformatics.Real-time PCR was used to detect the ADAR2 mRNA expression in the heart,liver,lung,kidney,spleen,brain,small intestine,muscle and backfat of 35-day-old pigs.Porcine ADAR2 cDNA sequence of 6305 bp was cloned,which contained 12 exons and encoded 704 amino acids.The nucleic acid and amino acid sequences shared a high identity(>84%)with that of other mammals including human,chimpanzee,macaque,gibbon,cow,goat and sheep.The deduced ADAR2 had two double-stranded RNA binding motifs and an adenosine deaminase domain.Real-time PCR results showed that the ADAR2 expressed in all the detected tissues,and had the highest expression in the lung.The full-length cDNA sequence of porcine ADAR2 gene was successfully cloned,and it was widely expressed in tissues of pigs.These findings provide a solid foundation for further function study of ADAR2.