龙眼胚性愈伤组织DlHOS1基因克隆与表达分析

以龙眼胚性愈伤组织为材料,采用RT-PCR和RACE-PCR技术对植物抗寒重要调控因子HOS1(DlHOS1)进行克隆,并进行密码子使用偏爱性、生物信息学和低温胁迫下表达等方面的分析。结果表明:DlHOS1基因序列全长3 577 bp,包含ORF 3 000 bp,编码999个氨基酸,5’UTR和3’UTR分别162 bp和415 bp(GenBank登录号:KY990404);密码子使用偏爱性分析表明,DlHOS1密码子的选择偏爱性较弱,偏爱以A/T结尾;生物信息学分析结果表明,DlHOS1编码的蛋白属于不稳定的疏水性跨膜蛋白,不含信号肽,定位于细胞质和细胞核,二级结构富含α螺旋,与柑橘的亲缘关系较近;qPCR结果发现,DlHOS1能够响应低温胁迫诱导,总体上低温下其表达水平上升。研究结果认为,DlHOS1参与龙眼抗寒和低温胁迫过程。 

Cloning and Expression Analysis of DlHOS1 in Embryogenic Callus of Dimocarpus longan Lour.

To study the function of HOS1 in cold stress of Dimocarpus longan Lour., the embryogenic callus of D.  longan Lour were used to clone HOS1 gene (DlHOS1) , and codon bias, bioinformatics and expression pattern of DlHOS1 were analyzed. The results showed that the full length sequence of DlHOS1  was  3 577 bp,  containing  an  ORF 3 000 bp,  encoding 999 amino acids,  and the 5’ UTR and 3’ UTR was 162 bp and  415  bp  respectively ( GenBank accession number: KY990404). The codon bias level of DlHOS1 was low， and it biased toward the synonymous codons with A and T at the third codon  position.  Bioinformatics  analysis  indicated  that  DlHOS1  was  an unstable and hydrophobic transmembrane protein, had no signal peptide and multilocated  in  cytoplasm  and  nucleus. The secondary structure was mainly composed of alpha helix and strand. Besides,  DlHOS1 shared a  very  close relationship with citrus. qPCR analysis showed that  DlHOS1  was  response  to  the  induction  of  low  temperature and up-regulated at low temperature. The research suggested that DlHOS1 should be involved in cold resistance and low temperature stress in longan.