TML functions in Arabidopsis pollen tube penetration into the stigma and style.

Decreased TML expression compromises pollen tube growth in the stigma and style, indicating that TML is critical for the penetration of pollen tubes into the stigma and style during pollination. In flowering plants, the penetration of the pollen tube into the maternal stigma tissue is a crucial step for successful pollination. Endocytosis is a vital process for pollen tube growth in vitro and in vivo. TML is one subunit of the TPLATE/TSET complex, the core complex for clathrin-dependent endocytosis. TML is localized in the lateral region of growing pollen tubes, but its function is unknown in pollen tube. In this study, we found that decreased TML expression compromises pollen tube growth in the stigma and style, despite comparable growth in vitro to the wild type. Our results indicate that TML plays a role in the penetration of pollen tubes into the stigma and style during pollination.