中国水仙NtPI基因的克隆与表达分析

采用RACE技术从中国水仙‘金盏银台’(Narcissus tazetta var.chinensis)花芽中获得1个与花器官发育有关的MADS-box基因,命名为NtPI(GenBank登录号:JQ326272).该基因全长804 bp,含有1个618 bp的开放阅读框,编码205个氨基酸,具有典型的MADS结构域和K结构域,与仙客来水仙(Narcissus cyclamineus)同源性最高,达98％.系统进化树显示,NtPI属于B类MADS-box基因家族的PI/GLO类基因.半定量RT-PCR分析表明,该基因在‘金盏银台’和‘玉玲珑’2种水仙花朵的各个部位均有表达,但表达的水平有所不同.在‘金盏银台’中,雄蕊和雌蕊的表达量大于花瓣和副冠,而在‘玉玲珑’花瓣和副冠中,表达丰度远远大于雄蕊和雌蕊.

Cloning and Expression Analysis of NtPI Homologous Gene from Narcissus tazetta var. chinensis

A flowering-related MADS-box gene named NtPI(GenBank accession JQ326272)was cloned from the flower bud of Narcissus tazetta var.chinensis using rapid amplification of cDNA ends.The cDNA is 804 bp in length with an open reading frame 618 bp which is capable of encoding 205 amino acids.The deduced amino acids sequence contained a typical MADS domain and a K domain.Homology analysis showed that NtPI shared 98% homology with Narcissus cyclamineus.Phylogenetic analysis indicated that NtPI belonged to the AP3/PI family PI lineage.RT-PCR revealed that the existence of NtPI was detectable in flowers,while the levels were much higher in stamen and pistil than in petal and corona from’Jinzhanyintai’,but the levels were much higher in petal and corona than in stamen and pistil from’Yulinglong’.