Involved in the formation of X-, Y-shaped and twinned plasmodesmata (PD), thus modelating PD size exclusion limit and regulating cell-to-cell transport. Cell cycle checkpoint regulator that monitors and responds to DNA damage such as DNA cross-links, and triggers the halt of the cell cycle progression in the presence of DNA cross-linking agents. Mediates the active process of aluminum- (Al) dependent root growth inhibition and thus is required for response to Al toxicity. Required for both early and late phases of embryo development as well as during seedling growth. Essential for signal transduction and development of both male and female organs