Involved in mitochondrial fragmentation during programmed cell death in response to high levels of alpha-factor mating pheromone or the drug amiodarone (PubMed:15657396, PubMed:18800175). May be involved in sterol transfer between intracellular membranes (PubMed:26001273). Localizes to puncta in the cell periphery representing cortical endoplasmic reticulum (cER)-plasma membrane (PM) membrane contact sites. The VASt domain bind sterols. Present with 1170 molecules/cell in log phase SD medium. Belongs to the SIP3 family.