May be involved in membrane trafficking (By similarity). Acts as a repressor of abiotic stress (e.g. drought and salt) responses by binding specifically to the promoter of THAS1 to regulate its transcription (PubMed:21252258). Binds to membrane lipid ceramides (PubMed:21252258). Interacts with the biotrophic pathogenic fungi Microbotryum violaceum effector MVLG_01732. Localized in the nucleus membrane of root tips cells. Mostly expressed in rosette leaves and flowers, to lower extent, in cauline leaves, roots and stems, and, at low levels, in siliques. The SMP-LTD domain is a barrel-like domain that can bind various types of glycerophospholipids in its interior and mediate their transfer between two adjacent bilayers. Enhanced drought and salt tolerance and modified gravitropic response associated with an increased expression of THAS1 (PubMed:21252258). Higher root lengths (PubMed:21252258). Belongs to the synaptotagmin family. Truncated N-terminus.