显花植物的雄配子是通过花粉管运送传递至雌配子体的。因此，花粉管的生长在有性生殖过程中起重要作用，与农业生产密切相关。为保证花粉管的正常生长，花粉及花粉管内的基因表达在转录水平和翻译水平上都会受到精确的调控。但目前对花粉管内基因表达的调控机制还知之甚少。我们在前期的探索研究中分离到一个严重影响花粉的萌发与花粉管生长的雄配子体突变体kd690。初步的分析结果显示，KD690基因编码一个预测具有DNA结合活性的ARID-HMG家族蛋白，主要在三细胞期之后的花粉及花粉管中表达，其产物蛋白初步定位于花粉的营养细胞核中，暗示其可能参与花粉中基因转录调控作用。本项目拟利用各种分子生物学、细胞生物学、生物化学、遗传学等方法进一步鉴定这个雄配子体突变体kd690及其相关基因的功能，探讨花粉管生长过程中的基因表达调控机制，为建立花粉管生长的遗传调控网络打基础。

The male gametes are delivered into the female gametophytes by pollen tubes in flowering plants.Therefore, growth of pollen tubes is important to sexual plant reproduction and tightly related to agricultural production. To ensure the normal growth of pollen tube, gene expression must be regulated precisely at transcriptional and translational levels in pollen grain and pollen tube. However, little has been known about the mechanisms that regulate gene expression in pollen tube. In our previous work, we isolated a male gametophytic mutant kd690 showing defect in pollen germination and pollen tube growth. KD690 gene encodes a putative DNA-binding protein that belongs to ARID-HMG family and is mainly expressed in pollen grains at three-cell and later stages and in pollen tube. The KD690-GFP protein was located in the nucluate of pollen vegetative cell, implying that it may be involved in regulation of gene transcription in pollen. This project is to further characterize the kd690 mutant and function of KD690 gene, to further understand the mechanism that regulates gene expression during pollen tube growth and prepare for the establishment of genetic regulation network in pollen tube growth.