Abstract
When a compatible pollen grain adheres to a papilla cell of a stigma in Brassicaceae, the pollen grain is hydrated and germinates the pollen tube. The pollen tube penetrates into the papilla cell wall and then enters the style. After these sequential steps, cross-fertilization can be achieved. In animal and plant cells, the oscillations of cytosolic Ca2+ occur in response to many kinds of extracellular stimuli. During pollination process, it is speculated that the oscillations of cytosolic Ca2+ occur in response to some stimuli from the pistil to regulate the pollen tube growth. In this study, we examined the distribution of Ca in the pollen grain and the papilla cell during pollination process using an EDX system fitted with the VP-SEM. Furthermore, we examined the Ca2+ dynamics during pollination process using Arabidopsis thaliana, into which the gene of a Ca2+ sensor protein, yellow cameleon, was transformed.
