摘要
利用PCR技术,从毛白杨花序材料中分离出一个MADS盒基因PtSEP3。蛋白序列比较和同源树分析表明,该基因与拟南芥SEP3同源。表达分析显示PtSEP3不仅在成年植株雌蕊和雄蕊中表达,也在幼茎、幼叶和顶芽中表达。在35S启动子驱动下,PtSEP3超表达的毛白杨转基因植株发生了明显的形态变化,表现为叶序不规则,在同一节间常数枚集生;并且叶片基部形态与野生型的心形不同,大部分为楔形。在离体条件下,在芽分化培养基上,PtSEP3转基因株系的根和叶外植体可以诱导发生带有花柱和子房室的子房状结构。试验结果说明PtSEP3参与了毛白杨花器官的发生,并可能在维持茎端分生组织分化出正常形态的叶片中也起着作用。
A MADS box gene PtSEP3 was isolated from young female flower of Populus tomentosa using PCR strategy. Alignment and homolog tree analyses show that PtSEP3 is a homologous gene of Arabidopsis SEP3. PtSEP3 expression can be detected not only in pistil and stamen, but young shoot, terminal bud and young leaf of an adult tree. Driven by 35S promoter, PtSEP3 over-expression leads to severe morphologic alterations in leaf phyllotaxis and in leaf form. In transgenic plants, several leaves USually initial from one stem node and leaf base most are cuneate, which are obviously different from alternate phyllotaxis and cordate leaf base in wild type. Ovary-like structures each with 1 - 2 styles and an ovate-form womb can be induced in volume, when leaf explants or root explants of transgenic lines are incubated on bud differentiation medium. The phenotypes in PtSEP3 over-expression lines combined with its expression pattern suggest it play roles in regulating floral organ initiation, nrobablv in maintenance of shoot meristem t）rooertv for correct initiation of normal leaves.
出处
《林业科学》
EI
CAS
CSCD
北大核心
2007年第4期36-42,共7页
Scientia Silvae Sinicae
基金
山东农业大学博士后基金资助
