Rice GLYCOSYLTRANSFERASE1 Encodes a Glycosyltransferase Essential for Pollen Wall Formation
Rice GLYCOSYLTRANSFERASE1 Encodes a Glycosyltransferase Essential for Pollen Wall Formation
复制标题
DOI：
10.1104/pp.112.210948
复制
发表时间：
2013-02-01
期刊：
影响因子：
7.4
通讯作者：
An, Gynheung
中科院分区：
文献类型：
--
作者：
Moon, Sunok;Kim, Sung-Ryul;An, Gynheung
花粉壁由外壁和内壁组成。其形成的机制还不清楚。糖基转移酶通过连接单个或多个糖来催化生物分子的修饰，并且在广泛的生物过程中发挥关键作用。我们研究了糖基转移酶1（OsGT 1）在水稻花粉壁发育中的作用。该基因在成熟花粉中高度表达，含有由转移DNA插入引起的等位基因的植物不产生纯合后代。OsGT 1/osgt 1和野生型之间的相互杂交表明，突变导致雄配子体缺陷。显微镜分析表明，osgt 1花粉发育正常的花粉有丝分裂阶段，但未能产生成熟的颗粒。osgt 1花粉内壁结构被破坏。此外，淀粉和蛋白质水平低得多的突变体籽粒。重组OsGT 1将葡萄糖从UDP-葡萄糖转移到糖基转移酶的通用底物槲皮素的第3和第7位。与OsGT 1的作用一致，OsGT 1-绿色荧光蛋白融合蛋白定位于高尔基体。综上所述，我们的研究结果表明，OsGT 1是高尔基体定位的糖基转移酶的内壁建设和花粉成熟所必需的，提供了新的见解男性生殖发育。
The pollen wall consists of an exine and an intine. The mechanism underlying its formation is not well understood. Glycosyltransferases catalyze the modification of biological molecules by attaching a single or multiple sugars and play key roles in a wide range of biological processes. We examined the role of GLYCOSYLTRANSFERASE1 (OsGT1) in pollen wall development in rice (Oryza sativa). This gene is highly expressed in mature pollen, and plants containing alleles caused by transfer DNA insertion do not produce homozygous progeny. Reciprocal crosses between OsGT1/osgt1 and the wild type indicated that the mutation leads to a male gametophyte defect. Microscopic analyses revealed that osgt1 pollen developed normally to the pollen mitosis stage but failed to produce mature grains. In osgt1 pollen, intine structure was disrupted. In addition, starch and protein levels were much lower in the mutant grains. Recombinant OsGT1 transferred glucose from UDP-glucose to the third and seventh positions of quercetin, a universal substrate of glycosyltransferases. Consistent with the role of OsGT1, an OsGT1-green fluorescent protein fusion protein was localized to the Golgi apparatus. Taken together, our results suggest that OsGT1 is a Golgi-localized glycosyltransferase essential for intine construction and pollen maturation, providing new insight into male reproductive development.