麻疯树基因JcKNOX1的克隆和表达调控分析

Cloning and expression regulation analysis of a JcKNOX1 gene, from Jatropha curcas L.

摘要:

KNOX同源异型盒基因在植物生长发育中扮演着极其重要的角色，首次从大戟科植物麻疯树cDNA中克隆到一个同源异型盒基因，命名为JcKNOX1.其开放阅读框全长693 bp，编码230个氨基酸残基，预测蛋白质等电点 pI=6.13，分子量 PA=25.92 KD．聚类分析表明，JcKNOX1与毛白杨在进化上具有最近的亲缘关系，其次是甜橙．荧光定量PCR检测发现，JcKNOX1基因在麻疯树植株各个器官中均有表达，幼嫩部位表达量明显高于成熟器官，表达量依次为：茎尖＞嫩叶＞茎＞叶＞花＞叶柄＞根；对麻疯树幼苗进行ABA和低温胁迫发现，JcKNOX基因表达量明显增加．上游调控元件预测分析表明，该基因可能在麻疯树光调节、激素调控、花粉基因特异性表达、逆境调控等重要生物学过程中具有重要作用．

Abstract:

KNOX family genes，coding homeobox proteins，play an inmportant role in plant development．A novel homeobox gene，JcKNOX1，was cloned from the cDNA of Jatropha curcas L.．The full-length ORF of JcKNOX1 was 693bp，encoding a protein of 230 amino acids residures．The predicted structure of JcKNOX1 showed that its theoretical isoelectric point and molecular weight were 6.13 and 25.92 kDa respectively．Phylogenic analysis indicated that JcKNOX1 was relation to Populus tomentosa and Citrus sinensis closely．By fluorescence quantitative PCR the expression levels were different as follows：stem apex>tender leaf>stem>leaf>flower>petiole>root，which showed that the JcKNOX1 expressed with high levels in developing organs．Meanwhile，JcKNOX was strongly induced by ABA and low temperature in Jatropha curcas L. seedlings．Through biology software prediction analysis indicated that JcKNOX1 might play an important role in light regulation，hormone regulation，expression of pollen-specific gene and abiotic stress of Jatropha curcas L.．