Involved in cellular calcium homeostasis regulation. May participate in differentiation and apoptosis of keratinocytes. Overexpression induces apoptosis. Interacts with PTPN2. Interacts with microtubules. Interacts with VAPB. Interacts (FFAT motif) with MOSPD2 (via MSP domain) (PubMed:29858488). In interphase localizes in the cytoplasm, and during mitosis localizes to the spindle microtubules and spindle poles. Present at high level in epidermis and seminiferous epithelium: while basal cells in the epidermis and spermatogonia show no perceptible amount, keratinocytes of suprabasal layers and differentiating first-order spermatocytes up to spermatids exhibit high expression. In skeletal muscle, its presence is restricted to fibers of the fast twitch type. In surface epithelia containing ciliated cells, it is associated with the microtubular structures responsible for ciliary movement. Also present in specific structures of the central nervous system such as neurons of the hippocampal region, ganglion cells of the autonomic nervous system, and axons of the peripheral nervous system (at protein level). Widely expressed. By EGF, TGFB1, retinoic acid- and 1,25-dihydroxyvitamin D(3). The transmembrane region is required for mitochondrial localization. The FFAT motif is required for interaction with MOSPD2. Belongs to the RMDN family. Truncated C-terminus.