芥蓝(Brassica alboglabra)苯丙氨酸解氨酶基因BaPAL的克隆、表达与序列分析

Cloning,expression and sequence analysis of a phenylalanine ammonia lyase gene BaPAL from Chinese kale(Brassica alboglabra)

根据NCBI数据库中拟南芥、甘蓝型油菜和菘蓝的苯丙氨酸解氨酶(phenylalanine ammonialyase,PAL)基因序列设计简并引物,从芥蓝叶片cDNA中克隆到1个PAL基因,定名为BaPAL.BaPAL编码区全长2 145 bp,编码714个氨基酸,在NCBI的登录号为FJ849059.半定量RT-PCR结果表明,BaPAL基因在茎、叶、花蕾、开放花朵和嫩角果中均有表达,而且以开放花朵的表达量最大,根中未能检测到.BaPAL与其他植物PAL序列比对的结果表明:芥蓝与甘蓝型油菜、白菜的关系最为接近,与同科的菘蓝和拟南芥的关系稍远,但它们都处于同一进化分支;跟蕨类植物的同源性最低,亲缘关系最远.

Degenerate primers were designed according to known phenylalanine ammonia lyase （PAL） gene sequences of Arabidopsis thaliana, Brassica napus and Isatis indigotica. A gene, designated BaPAL, was isolated from leaf cDNA of Chinese kale （B. alboglabra）. Sequence analysis showed that the coding sequence of 13aPAL was 2 145 bp in length encoding 714 amino acids. BaPAL gene sequence was submitted to NCBI under the accession number FJ849059. Semi-quantitative RT-PCR was applied using roots, stems, leaves, flower buds, open flowers and siliquas cDNA as PCR templates, respectively. Results indicated that BaPAL gene was expressed in all organs with the exception of roots, and was highly expressed in open flowers. Sequence comparison of BaPAL and PALs from other plants revealed that B. alboglabra, B. napus and B. rapa var. Chinensis were the closest relatives. B. alboglabra had a closer relationship and shared the same clade in phylogenetic tree with I. indigotica and A. thaliana. However, it was distantly related to ferns for their low sequence homology.