拟南芥短肽激素PROPEP基因家族在根生长中的作用机理

Mechanism of Arabidopsis Short Peptide Hormones PROPEP Gene Family in the Root Growth

AtPROPEP是拟南芥(Arabidopsis thaliana)具有7个成员的基因家族,编码内源短肽激素。AtPROPEP基因家族编码的蛋白质C端23个氨基酸短肽能够被2个同源激酶受体AtPEPR1和AtPEPR2识别并结合,引起下游反应。然而,对于该家族成员AtPROPEP2,3-6的表达对茉莉酸(JA)和水杨酸(SA)的响应以及在根生长中的作用并不清楚。GUS染色和定量RT-PCR分析结果表明,AtPROPEP2–6的表达对于JA和SA的响应不同,暗示着它们可能通过不同的方式参与植物的先天免疫反应。AtPROPEP3和At PROPEP4过表达植株的表型分析表明,AtPROPEP3和AtPROPEP4促进拟南芥根的生长。

At PROPEP is a 7-member gene family in the Arabidopsis genome that encodes an endogenous peptide hormone. The C-terminal of the encoded proteins, about 23 amino acids, can be recognized by the corresponding receptors At PEPR1 and At PEPR2, which in turn evoke downstream cascades. Whether At PROPEP2–6 respond to jasmonic acid and salicylic acid is unknown, as is their roles in root development. In this study, GUS staining and quantitative RT-PCR revealed that At PROPEP2–6 expression had various responses to jasmonic acid and salicylic acid treatments, which implies their roles in innate immunity. In addition, Arabidopsis overexpressing At PROPEP3 and AtPROPEP4 had significant longer roots than did the wild type.