中华蟾蜍RAC2基因的克隆与表达分析

Cloning and expression analysis of RAC2 gene in bufo gargarizans cantor

为了探究中华蟾蜍Ras相关C3肉毒菌毒物底物2(Ras-related C3 botulinum toxin substrate 2,RAC2)基因(BgsRAC2基因)在细胞增殖中的作用,试验对中华蟾蜍RAC2基因进行了全长cDNA序列扩增并对其编码蛋白质进行生物信息学分析,同时检测分析了BgsRAC2基因在8种组织/器官中的表达情况。结果表明:克隆获得RAC2基因全长765 bp,其开放阅读框(ORF)为579 bp,编码192个氨基酸;BgsRAC2氨基酸序列与非洲爪蟾的相似度最高,达96.88%;BgsRAC2蛋白的分子质量为21.36 ku,理论等电点为7.54,二级结构多为无规则卷曲,含Rho家族标志性保守结构域,无信号肽和跨膜结构域;BgsRAC2基因在肾脏中相对表达量最高,在耳后腺中表达量最低,在耳后腺和皮肤中的相对表达量显著低于舌、心脏和肾脏(P<0.05)。结合RAC2功能,推测BgsRAC2基因可能与中华蟾蜍造血细胞增殖有关。

In order to investigate the role of Ras-related C3 botulinum toxin substrate 2(RAC2) gene in cell proliferation of Bufo gargarizans, the full-length cDNA of RAC2 gene of Bufo gargarizans was amplified and its coding protein was analyzed by bioinformatics. At the same time, the expression of BgsRAC2 gene in 8 tissues/organs was analyzed. The results showed that the BgsRAC2 gene cDNA sequence length was 765 bp, and its open reading frame(ORF) was 579 bp that encoded 192 amino acids. The amino acid sequence encoded by the BgsRAC2 gene had 96.88% homology with the Xenopus laevis RAC2 gene. The molecular weight of BgsRAC2 protein was 21.36 ku, and the isoelectric point was 7.54. The secondary structure of BgsRAC2 protein was mostly random coil, containing Rho family landmark conserved domain, no signal peptide, and no transmembrane region. The relative expression of BgsRAC2 gene was the highest in kidney and the lowest in retroauricular gland, the relative expression levels in retroauricular glands and skin were significantly lower than in tongues, hearts and kidneys(P<0.05). Combined with the function of RAC2, it is speculated that BgsRAC2 gene may be related to proliferation of hematopoietic cells of Bufo gargarizans.