桃(Prunus perscia)中一个AGAMOUS同源基因第二内含子序列的克隆和鉴定

本研究首先从桃中克隆了AGAMOUS(AG)同源基因PpMADS4的第二个内含子--pPpMADS4，全长约2.1kb。序列分析表明，该内含子含有一些对基因表达十分重要的调控元件。同时，克隆了七个不同桃品种中的PpMADS4基因的第二内含子，序列比对和SNP测算表明，PpMADS4第二内含子是一段SNP富集区域，具有高度的核苷酸多态性，但是在这段序列上各个调控元件的序列和位置都非常保守，暗示了这些调控元件可能具有很重要的生物学功能。为了认识这一内含子的调控功能，将pPpMADS4与minimal35S连接并与GUS基因融合，构建表达载体转入野生型拟南芥中。GUS染色显示，其表达主要分布在花的两轮生殖器官上，这与拟南芥中AG第二内含子调控的GUS着色部位相似，但存在着差异。PpMADS4第二内含子能够特异启动GUS在花发育晚期的表达。

Cloning and Identification of the Second Intron of an AGAMOUS-like Gene from Peach (Prunus persica)

In this study the second intron, pPpMADS4, of an AGMOUS (AG) homologous gene PpMADS4 was cloned from peach (Prunus persica) and its function studied in transgenic Arabidopsis thaliana. Sequence analysis revealed the presence of several putative cis elements in the second intron of PpMADS4, and all the second introns cloned from seven different peach cultivars possess highly conserved cis elements although SNP-rich regions were identified. Furthermore, the pPpMADS4∷minimal35S∷GUS-0029 vector were constructed and transformed into wild-type A. thaliana. β-glucoronidase staining showed that it was expressed specifically in carpel and stamen at late floral developmental stage.