橄榄CaICE1基因的克隆和表达分析

Cloning and Expression Analysis of the CaICE1 Gene in Canarium album

为了解橄榄(Canarium album)抗寒相关转录因子ICE1的调控功能,采用RT-PCR技术克隆了‘福榄1号’的ICE1,命名为CaICE1,并进行生物信息学、qRT-PCR表达模式和相关miRNA预测分析。结果表明,CaICE1 cDNA序列的开放阅读框长度为1 650 bp,可编码549个氨基酸(GenBank登录号MG459422)。Ca ICE1为不稳定亲水性蛋白质,含有跨膜结构、磷酸化位点以及HLH保守结构域,定位于细胞核,与枳的ICE1亲缘关系较近。CaICE1密码子偏好性较弱,AGA、AGG、TGG和CCA可能为其最优密码子群。CaICE1主要在橄榄花、种子和叶中大量表达,-3℃低温胁迫下CaICE1表达水平比常温显著上升。psRNAtarget预测结果表明,CaICE1可能是miR825、miR477、miR5658、miR1436和miR394等多个逆境响应miRNA的靶基因。因此,CaICE1可能在橄榄低温胁迫过程中发挥重要调控作用,且可能受miRNA的调控。

To understand the regulatory function of cold resistance transcription factor ICE1 in Canarium album, one ICE1 gene, named CaICE1, was cloned from ‘Fulan-1’ by using RT-PCR, and its bioinformatic characteristic, expression pattern and predicted targeting miRNAs were studied. The results showed that the length of open reading frame of CaICE1 was 1 650 bp, encoding 549 amino acids （GenBank accession No. MG459422）. The CaICE1 was an unstable and hydrophilic protein located at nucleus, with transmembrane structure, phosphorylation sites and conserved HLH domains, and which had close relationship with ICE1 of Citrus trifoliata. Although the codon bias level was low, AGA, AGG, TGG and CCA would be optimal codons of CaICE1. The expression of CaICE1 was high in flower, seed and leaf, and which was significantly up-regulated under -3℃ compared with room temperature. Additionally, CaICE1 was predicted to be targeted by several stress responsive miRNAs, such as miR825, miR477, miR5658, miR1436 and miR394. Therefore, it was suggested that CaICE1 might play important regulation roles in low temperature stress of C. album, and its expression might be regulated by some stress responsive miRNAs.