香蕉MaMYBR1基因的克隆和表达分析

Cloning and Expression Analysis of MaMYBR1 Gene from Banana

为研究MaMYBR1基因参与香蕉响应的胁迫过程,本研究利用RT-PCR获得香蕉MaMYBR1基因的全长,包含786个核苷酸,编码261个氨基酸。将该基因核苷酸序列在NCBI进行BLASTn比对,发现该基因与大麦(AK359880)、花药野生稻(XM_015836768.1)和小麦(AB252147.1)的基因序列具有较高的相似度,相似度分别为80.06%、79.19%和79.19%。蛋白结构域分析发现该基因编码的蛋白质序列包含有一个MYB结构域和一个SANT结构域。系统进化树分析表明,该蛋白与海枣(XP_008785342.1)和油棕(XP_010920477.1)等植物亲缘关系较近。通过实时荧光定量PCR分析表明MaMYBR1以上调表达模式参与香蕉响应低温、干旱和盐等胁迫过程,其中在低温胁迫下MaMYBR1基因的相对表达量变化最大;MaMYBR1基因在接种枯萎病菌的抗病品种中显著上调表达,而在感病品种中显著下调表达,MaMYBR1基因可能参与香蕉抗枯萎病过程。因此,本研究将为后续香蕉遗传改良提供有价值的研究信息。

To investigate MaMYBR1 gene in the stress process in response to banana response,the coding sequen-ces of banana MaMYBR1 gene was obtained by RT-PCR.It is found that the gene contains 786 nucleotides and encodes 262 amino acids by sequencing.The gene nucleotides sequence alignment on NCBI website for BLASTn showed that the gene was highly similarity with the gene of Hordeum vulgare(AK359880),Oryza brachyantha(XM_015836768.1)and Triticum aestivum(AB252147.1),and the similarity was 80.06%,79.19%and 79.19%,re-spectively.The analysis of protein domain showed that the protein sequence encoded by the gene contained one MYB protein domain and one SANT protein domain phylogenetic tree analysis showed that the protein was most closely related to the dates(XP_008785342.1)and the oil palm(XP_010920477.1).MaMYBR1 involved in respond to low temperature,drought and salt stresses by real-time fluorescence quantitative PCR analysis,of which the expression level of MaMYBR1 greatest changed under low temperature stress.The expression of MaMYBR1 was significantlyup-regulated in resistant varietiesinoculated with Fusarium wilt,whereas down-regulated in susceptible varieties,which might participate in the process of resistance to Fusarium wilt in banana.Therefore,this study will provide valuable research information for subsequent banana genetic improvement.