莲NnFUL基因克隆、亚细胞定位及表达分析

Cloning,subcellular localization and expression analysis of NnFUL genes from lotus(Nelumbo nucifera Gaertn.)

为了研究MADS—box A类基因在莲花器官发育中的作用,以莲品种‘大洒锦'(Nelumbo nucifera‘Da sajin')的花蕾为试验材料,利用RT-PCR方法克隆了莲FUL-like基因cDNA序列,命名为NnFUL。NnFUL的cDNA长度为763 bp,其开放阅读框(Open reading frame,ORF)共编码250个氨基酸。该蛋白属于亲水性蛋白,二级结构主要由α-螺旋、无规则卷曲和延伸链组成。系统进化分析表明:NnFUL编码的蛋白与AP1/SQUA亚家族中的FUL-like蛋白聚为一类,与二球悬铃木(Platanus×acerifolia)的FUL-like蛋白具有较高的亲缘关系。亚细胞定位显示该基因位于细胞核中。荧光定量Real-time PCR结果表明:NnFUL在花器官中表达量最高,主要集中在花萼和花瓣中,同时在营养器官中也有表达;因此,NnFUL在花器官发育尤其花萼和花瓣形成中有一定的调控作用。

To investigate the effect of FUL-like merit of Nelumbo nucifera, flower buds of N. nucifera gene of A-class MADS-box family on floral organ develop- ＇ Da Sajin＇ were used as a test material and a cDNA of a FUL-like gene,being named NnFUL and 763 bp long, was successfully cloned by RT-PCR. The cDNA＇ s open reading frame （ORF） encodes 250 amino acids totally. The NnFUL protein is hydrophilic and its secondary struc- ture mainly consists of a-helical, irregularly curled and extended strands. The phylogenetic analysis showed that the NnFUL protein belongs to a class of FUL-like protein in AP1/SQUA subfamily and has a close genetic rela- tionship with FUL-like protein of Platanus x acerifolia. The subcellular localization indicated that the gene NnFUL is located in the cell nucleus. The fluorescent quantitation real-time PCR analysis showed that NnFUL has the highest expression level in the floral organ, mainly concentrating in the sepals and petals, and also has some expression in the vegetative organs. Therefore, the gene NnFUL has a certain regulatory effect on development of both sepals and petals in lotus flowers.