烟草GA代谢相关基因ga1和ga2的克隆和表达分析

Cloning and Expression Analysis of ga1 and ga2 in Tobacco

摘要: 为了解赤霉素（gibberellic acids， GA）在烟草生长发育中的作用，本研究利用同源克隆和RACE技术分离了3个烟草种GA代谢相关基因ga1和ga2的6条序列，对其进行了序列比对和进化分析；并利用荧光定量表达分析研究了其在林烟草和普通烟草中的表达谱。结果表明，相关基因在烟草属和茄科作物中保守性很高；普通烟草中克隆的ga1和ga2可能起源于绒毛状烟草。表达分析表明，ga1和ga2在林烟草生长发育早期和茎伸长期分别在叶和茎中的表达量显著高于其他组织。

Abstract: Two GA metabolism related genes ga1 and ga2 were cloned by using homology-based method and RACE from three tobacco species to explore the role in which gibberellic acids (GA) play in tobacco growth and development. Based on sequence alignment, a phylogenetic tree was constructed. qRT-PCR was executed to detect the gene expression profiles in Nicotiana sylvestris and Nicotiana tabacum. The results showed that they were highly conserved in sequences in solanaceae plants and genes in N. tobacum might originate from Nicotiana tomentosiformis. qRT-PCR analysis showed that ga1 and ga2 were expressed in much higher levels in leaves of stage before stem elongation and in stem of the stem elongation stage than other tissues in N. sylvestris.