人参BBM基因全长cDNA的克隆及生物信息学分析

Cloning and sequence analysis of the full-length cDNA of BBM gene from panax ginseng

BBM(BABY BOOM)基因是属于植物AP2/EREBP基因家族的AP2亚族的转录因子,已有很多研究表明,过量表达BBM基因能够诱导植物体细胞胚,是植物体细胞胚诱导研究中应用潜力大的重要基因之一。为利用BBM基因诱导人参体细胞胚,该试验采用RACE方法克隆了2 291 bp的人参BBM基因全长cDNA,包含1 998 bp的开放阅读框(ORF),编码665个氨基酸。用其推测的编码蛋白序列与拟南芥等植物的BBM基因序列比对结果,人参BBM基因中包含euANT2-euANT6、bbm-1等基序,还包含由Linker连起来的2个AP2结构域(AP2-R1和AP2-R2),说明PgBBM是属于AP2亚族的转录因子。与其它植物已知BBM基因构建的系统发育树显示,人参BBM基因与烟草、大豆、苜蓿的BBM基因亲缘关系较近,与其它植物的BBM基因的亲缘关系较远。

BBM(BABY BOOM) gene is a transcription factor, belonging to AP2 of AP2/ERF superfamily. Many studies indicated that over-expression of BBM gene can induce plant somatic embryos. It is one of the important genes in study of plant somatic embryo induction. To induce ginseng somatic embryo by BBM gene, in present study, the gingseng BBM gene designated as PgBBM was cloned by the RACE technique. PgBBM cDNA cloned was 2594 bases long containing an ORF of 1998 bases and encoding a protein comprised of 665 amino acids. The result of deduced amino acid sequence of the BBM protein encoded by PgBBM compared with other BBM proteins showed that PgBBM trotein contained the motifs of euANT2-euANT6 and bbm-1, two AP2 domains(AP2-R1 and AP2-R2), and a linker region lying between them(Linker) which indicate that the PgBBM belonged to the AP2 family. Phylogenetic analysis showed that the PgBBM were most closely related to the BBM orthologue genes identified in Nicotiana tabacum,Glycine max and Medicago truncatula.