柑橘CjGH3.4和CjGH3.7基因的生物信息学分析及表达分析

以资阳香橙(Citrus junos Sieb.ex Tanaka)为材料,基于柑橘全基因组对两个生长素酰胺合成酶基因GH3(Gretchen Hagen 3),即Cj GH3.4和Cj GH3.7进行生物信息学分析及表达分析。结果表明:Cj GH3.4的开放阅读框(ORF)长度为1 830 bp,编码609个氨基酸;Cj GH3.7的ORF为1 800 bp,编码599个氨基酸。基因结构分析显示Cj GH3.4含有两个内含子,Cj GH3.7含有3个内含子。通过比对发现,这两个基因编码的蛋白序列与拟南芥、水稻、大豆、杨树等具有的较高的同源性,相似度可达66%~81%。Cj GH3.7主要在叶组织中表达,Cj GH3.4在根和叶组织中表达均较高,且叶高于根。在根和叶组织中,Cj GH3.4和Cj GH3.7均受低温、高盐以及PEG胁迫诱导,表明其参与了柑橘逆境响应过程。Cj GH3.4和Cj GH3.7在叶中受到ABA、ACC、Me JA和SA等诱导,在根中却受到抑制,呈现相反的表达模式。

Bioinformatics and Expression Analysis of CjGH3.4 and CjGH3.7 Genes in Citrus

Based on genomic sequences of citrus，bioinformatics and expression analysis of two GH3 （Gretchen Hagen 3）genes，i.e. CjGH3.4 and CjGH3.7 were done in Citrus junos Sieb. ex Tanaka. The Open Reading Frame（ORF）of CjGH3.4 and CjGH3.7 contained 1 830 bp and 1 800 bp，encoding a protein of 609 and 599 amino acid residues，respectively. Comparing cDNA with their corresponding DNA sequences showed that 2 and 3 introns were contained by CjGH3.4 and CjGH3.7，respectively. CjGH3.4 and CjGH3.7 shared 66%–81% amino acids identities with other plant GH3s from Arabidopsis，Oryza sativa，Glycine max and Populous trichocarpa. CjGH3.7 predominantly expressed in leaves，CjGH3.4 highly expressed in both leaves and roots with slightly higher expression level in leaves. In roots andleaves，CjGH3.4 and CjGH3.7 were both up-regulated by cold，salt and PEG，indicating their pleiotropic roles in stresses. Additionally，these two genes were also induced by ABA，ACC，MeJA and SA in leaves，and inhibited in roots，showing opposite expression pattern.