巴西橡胶树HbHDT1基因的克隆及表达分析

Cloning and Expression of a HbHDT1 Gene from Hevea brasiliensis

根据一个已获得的在巴西橡胶树幼态无性系与老态无性系之间差异表达的SSH片段的序列信息设计引物,通过RACE的方法获得橡胶树编码组蛋白去乙酰化酶(histone deacetylase)的cDNA(命名为HbHDT1)。序列分析结果表明,HbHDT1长为1197bp,含有917bp的阅读框,86bp的5'-UTR和196bp的3'-UTR,编码304个氨基酸。该氨基酸序列与蓖麻、毛果杨、马铃薯、红花苜蓿、大豆、小麦的HDACs家族成员的同源性分别为65%、59%、50%、45%、43%和40%。半定量RT-PCR分析结果表明HbHDT1在巴西橡胶树的花、愈伤组织、胚、叶、芽、胶乳中均有表达。在体细胞胚发生过程中HbHDT1表达出现明显的差异,在培养12d的体细胞胚中表达量最低,在培养53d的体细胞胚中表达量最高。茉莉酸和乙烯处理对胶乳中HbHDT1的表达无影响。

The full-length cDNA encoding a histone deacetylase, designated HbHDT1, was isolated from rubber tree based on the information about the sequence from a differentially expressed clone （designated as HbSSH12） encoding a histone deacetylase that was cloned recently by the subtractive hybridization between the juvenile and the donor clones from rubber tree （Hevea brasiliensis）. Sequence analysis revealed that the ORF of HbHDT1 encodes 304 amino acid residues with a total predicted molecular mass of 32.9 kD. The deduced amino acid sequences of HbHDT1 showed high identities （65%, 59%, 50%, 45%, 43% and 40%, respectively） to those of the histone deacetylase from Ricinus communis, Populus trichocarpa, Solanum chacoense, Trifolium pretense, Glycine max and Triticum aestivum. The RT-PCR analysis indicated that the transcripts of the HbHDT1 were differentially expressed in the flower, callus, embryos, leaf, bud and latex of the rubber tree. The transcription of HbHDT1 was not induced in the latex by jasmonic acid and ethylene.