日本晚樱PrseSHP基因的克隆与功能分析

Cloning and Function Identification of PrseSHP Gene from Prunus lannesiana(Rosaceae)

采用同源克隆方法结合RACE技术,从日本晚樱（Prunus lannesiana）品种‘大岛樱’中克隆到花发育调控相关的PrseSHP基因（GenBank登录号为GU362645）。PrseSHP基因序列全长1 223bp,包含1个长741bp的完整开放阅读框,编码246个氨基酸和1个终止密码子。分子系统发生分析表明,PrseSHP属MADS-box转录因子的PLE/SHP进化系,并与蔷薇科植物的SHP同源蛋白聚于同一进化分支;蛋白序列比对显示,该转录因子拥有M、I、K和C共4个结构域,且其C末端结构域中包含高度保守的AGⅠ和Ⅱ基序。基因表达分析表明,PrseSHP基因主要在‘大岛樱’的花瓣、雄蕊、雌蕊和幼果等器官中表达,在花萼中仅能检测到微弱的转录信号,在幼叶中不表达,与其他植物SHP同源基因的表达模式有一定的差别。功能分析显示,转PrseSHP基因拟南芥植株明显比野生型拟南芥弱小,转基因拟南芥在6~8片莲座叶后即抽薹开花,时间较野生型拟南芥（14~17片莲座叶后抽薹开花）明显提前,证明异位表达的PrseSHP基因能促进拟南芥早花,其在花发育过程中可能参与调控植物开花。

Full cDNA of one MADS-box gene,PrseSHP with GenBank accession No.GU362645,was cloned from Prunus lannesiana using homologous cloning and RACE method.The full length of PrseSHPcDNA is 1 223 bp,containing an open reading frame（ORF）of 741 bp and coding for a polypeptide of 246 amino acid residues.Sequence and phylogenetic analyses grouped PrseSHP into PLE/SHP lineages of the MADS-box family.Conceptual translation revealed that PrseSHP contain MADS,I,K and C domains.Expression analysis suggested that PrseSHPexpressed mainly in petal,stamen,gynoecium and young fruit of P.lannesiana‘Makino＇.Moreover,functional analysis suggested that transgenic Arabidopsis was obviously dwarf,and flowering during 6-8rosette leaves,which was early than that of wild-type Arabidopsis who was flowering during 14-17 rosette leaves.Ectopic expression of PrseSHPcould obviously promote flowering of transgenic Arabidopsis.Our results suggest that PrseSHPare involved in flowering in Cherry Blossom.