Involved in the formation of X-, Y-shaped and twinned plasmodesmata (PD), thus modelating PD size exclusion limit and regulating cell-to-cell transport (PubMed:22411811). 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. Essential for signal transduction and development of both male and female organs (By similarity). Reduced plasmodesmata (PD)-mediated horizontal and vertical cell-to-cell transport in leaves. Belongs to the plant DSE1 protein family.