PzIPT1在拟南芥精细胞中表达的分子机理研究

项目名称： PzIPT1在拟南芥精细胞中表达的分子机理研究

项目编号： No.31471402

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 发育生物学与生殖生物学

项目作者： 苟小平

作者单位： 兰州大学

项目金额： 85万元

中文摘要： 被子植物成熟花粉或萌发花粉管中含有的两个精细胞和营养细胞核组成雄性生殖单位，其中一个精细胞将和卵细胞融合形成胚胎，另一个精细胞将会与中央细胞融合形成胚乳。过去十多年的研究表明精细胞具有丰富的基因表达，而且精细胞表达的转录本对精细胞的发育、分化以及双受精后胚胎的正常发育至关重要。但是迄今为止，对精细胞基因表达调控的研究非常有限。申请人在前期工作中鉴定到一个在精细胞中而不在花粉营养细胞中表达的异戊烯转移酶基因（PzIPT1），并克隆到其启动子，初步实验表明该启动子含有至少两个顺式调节元件，能够精确调控报告基因在拟南芥精细胞而不是营养细胞中的表达以及强度。本项目将详细剖析该启动子中顺式调节元件的结构，寻找相应的结合蛋白并研究其功能，鉴定更多调控精细胞基因表达的基因，从而深入研究被子植物精细胞的基因表达调控机理。

中文关键词： 精细胞；基因表达调控；顺式调节元件；启动子；异戊烯转移酶

英文摘要： A male germ unit (MGU) consists of one vegetative nucleus and two sperm cells in mature pollen or pollen tube, which is transported and functions as an assemblage during fertilization in angiosperms. One sperm cell will fuse with the egg cell to form the zygote and embryo; the other will fuse with the central cell to form endosperm. Studies in the past decade indicated that sperm cell had abundant expressed transcripts essential to sperm development, differentiation and embryo development after double fertilization. However, studies of the regulation of sperm cell gene expression are still limited. The PI's group identified a sperm cell-expressed gene PzIPT1 encoding an isopentenyl transferase that is not expressed in the vegetative cell of Arabidopsis. The cloned promoter has at least two cis-regulatory elements to finely regulate the expression specificity and strength of PzIPT1 in sperm cells. This project will dissect the structures of the cis-regulatory elements of PzIPT1 in detail; identify the corresponding binding proteins and reveal their functions; screen more genes regulating sperm cell gene expression. This study will help to reveal the regulation mechanisms of sperm cell gene expression in angiosperms.

英文关键词： Sperm cell;regulation of gene expression;cis-regulatory element;promoter;isopentenyl transferase