Involved in cellular calcium homeostasis regulation. Interacts with PTPN2. Interacts with microtubules. Interacts with VAPB. Interacts (FFAT motif) with MOSPD2 (via MSP domain). In interphase localizes in the cytoplasm, and during mitosis localizes to the spindle microtubules and spindle poles. The FFAT motif is required for interaction with MOSPD2. Belongs to the RMDN family.