Abstract
Female gametophyte plays a critical role in essentially every step of the reproductive process. One of the most important functions of the female gametophyte is the pollen tube guidance. Within the female gametophyte, synergid cells are required for pollen tube guidance (Higashiyama et al. 2002). Although the cellular functions of the synergid cells have been understood, little is known for the molecular-level function of the synergid cells. However, Kasahara et al. identified a key gene, MYB98. To investigate genes essential for the development and function of the synergid cell, we started forward genetics approach by using MYB98::GFP visible screening and identified a male gametophytic mutant, g21. Although a pollen grain has two sperm cells in wild type Arabidopsis, g21 mutant has only single sperm-like cell inside of the pollen grain. Because of the single sperm-like cell, g21 mutant shows fertilization defect even though the mutant pollen tubes get into the female gametophyte. In this meeting, we report that we discovered a remarkable function during plant fertilization. This newly identified function will deeply contribute to gain insight of the plant fertilization event.
