茶树叶片GDH、GS、GOGAT基因的克隆及荧光定量PCR分析

Molecular Cloning and Quantitative Analysis of GDH,GS and GOGAT Genes from Leave of Tea Plant

以4个茶树种质为试验材料,克隆得到茶叶中氨基酸合成转化关键酶基因:谷氨酸脱氢酶(GDH)、谷氨酰胺合成酶(GS)、谷氨酰胺α-酮戊二酸氨基转移酶(GOGAT)的保守区。在GenBank登录号分别为:JN602371、JN602372、JN602373。通过SYBR Green I实时荧光定量PCR检测,发现GDH酶基因在茶树种质0314C(相对高氨基酸种质)中的表达显著增强,而在0212-15种质(相对低氨基酸种质)中却显著下降。GS、GOGAT酶基因在种质0314C中表达显著下降,而在0212-15、0318D种质中显著增强。通过回归分析,GS基因表达与茶氨酸、赖氨酸、丙氨酸呈负相关,而GDH与茶氨酸呈正相关。

This research has separated gene conservative regions of glutamate dehydrogenase（GDH）,Glutamine synthetase（GS） and Glutamine oxoglutarate aminotransferase（GOGAT）,which were key enzymes involving in the metabolism of amino acid in tea plant,from four tea germplasms.Sequences of GDH,GS and GOGAT conservative regions have been submitted to GeneBank and their accession number were JN602371,JN602372 and JN602373,respectively.Real-time quantitative PCR analysis revealed that GDH gene has higher transcription in 0314C（germplasm with relatively high amino acid content） than the other three germplasms,while lower transcription in 0212-15（germplasm with relatively low amino acid content） comparing to the others.The transcription of GS and GOGAT gene were in apparently low level in 0314C and high level in 0212-15 and 0318D,respectively.Regression analysis indicated that the expression of GS gene was negatively related to the contents of theanine,lysine and lactamine,whereas the expression of GDH gene was positively related to the content of theanine.