火龙果HuICE1基因的克隆与表达分析

Cloning and Expression Analysis of HuICE1 Gene in Pitaya

本研究以‘金都一号’红心火龙果(Hylocereus undatus)为实验材料,利用ICE序列3’端的高度保守结构域(bHLH),采用同源克隆法从火龙果果肉中分离得到一条HuICE1序列,其cDNA序列全长1673 bp,具有一个1596 bp的完整开放阅读框,生物信息学分析显示该基因编码的蛋白定位于细胞核,为水溶性蛋白。蛋白结构预测发现,HuICE1蛋白属MYC2型转录因子,在3’端第340~384个氨基酸含有高度保守的bHLH结构域,表明HuICE1基因属bHLH家族,还有核定位信号(NLS)区、富S区、转膜区、类泛素化(SUMO)结合位点各1个。同源性分析表明,火龙果与甜菜(Beta vulgaris)的核苷酸序列相似度最高,为85.10%。qRT-PCR表达分析表明,在火龙果各个组织中HuICE1均有表达,说明该基因是组成型表达,此研究为后续研究火龙果抗逆机制提供理论依据。

The variety of pitaya(Hylocereus undatus)’Jindu No.1’were as the materials,Using the highly conserved domain(bHLH)at the 3’end of the ICE sequence.A HuICE1 sequence was isolated from the pitaya pulp by homologous cloning.The full-length sequence of c DNA was 1673 bp with an open reading frame of 1596 bp,encoding 531 amino acids and containing a bHLH domain of MYC2 type.The predicted HuICE1 protein contained a nuclear localization signal(NLS),a serine-rich region(S-rich),a trasmembrane domain,a Ubiquitin-like(SUMO)binding site.Homology analysis showed that the nucleotide sequence similarity between pitaya and beet(Beta vulgaris)was the highest,which was 85.10%.Analysis of qRT-PCR showed that HuICE1 was expressed in various tissues of pitaya,it might be obvious that ICE1 gene expression would be constitutive.This study laid the foundation for the subsequent study of the anti-reverse mechanism of pitaya.