Abstract
The exine composing the outer wall of pollen grains shows highly diverged structures among higher plants, suggesting it plays important roles for successful pollination. However, little is known about its formative process nor genes involved in its construction. We screened mutagenized Arabidopsis thaliana by SEM observation for plants that have pollen grains with abnormal exine structures. We obtained 12 mutants, named kaonashi (kns), whose exine showed atypical mesh patterns. Since most of these phenotypes have never been reported, this screening seems very effective to identify many novel genes involved in exine formation. Interestingly, many kns mutants did not show remarkable sterility, indicating that the correct structure of exine might be not necessary for the pollination. Map-based cloning of two kns mutants is in progress; kns2 showing fine mesh pattern of exine, and kns4 showing very thin exine layer.
