花粉萌发和花粉管生长是植物有性生殖的关键步骤，高尔基体的细胞壁多糖合成及蛋白质糖基化修饰功能在其中扮演重要角色。为了确保蛋白质糖基化和细胞壁多糖合成的正确进行，参与这些过程的糖基化酶和糖基转移酶必须有序定位在高尔基体不同部位，而调控这些酶定位的分子机制目前还很不清楚。在酵母和哺乳动物中,一个由八个亚基组成的蛋白复合体- - COG(Conserved Oligomeric Golgi)复合体在高尔基体糖基化酶和糖基转移酶的运输和定位过程中作为拴系因子而发挥了关键的功能。我们前期的研究发现拟南芥COG复合体中的COG3亚基的基因突变后，导致花粉管不能正常萌发和生长。因此我们准备从拟南芥COG3基因及其突变体入手，探索COG3亚基以及COG复合体在高尔基体糖基化酶和糖基转移酶定位中的功能及其对花粉萌发和花粉管生长的影响。

Pollen germination and pollen tube growth is crucial for higher plant reproduction. It requires proper protein glycosylation and cell wall polysaccharide synthesis which happen in specific loci of Golgi apparatus. Despite extensive studies, our knowledge about the exact molecular mechanisms of achieving proper localization of enzymes responsible for protein glycosylation and cell wall polysaccharide synthesis in pollen Golgi apparatus are limited. In yeast and mammalian cells, an octamer protein complex named Conserved Oligomeric Golgi (COG) complex is implicated in this process. we found an Arabidopsis mutant defective in COG3 subunit of COG complex causing defects in pollen germination and tube growth. Detailed characterization of this cog3 mutant,COG complex organization, COG3 protein expression assay etc. will help us understand the function of COG complex in the localization of key enzymes which is indispensable for pollen germination and tube growth.