May be implicated in endosomal trafficking, or microtubule dynamics, or both. Participates in cytokinesis (PubMed:20719964). Interacts with ITCH and WWP1 (PubMed:19580544). Interacts (via MIT domain) with IST1; leading to the recruitment of SPART to midbodies (PubMed:20719964). Transiently associated with endosomes (PubMed:19580544). Colocalized with IST1 to the ends of Flemming bodies during cytokinesis (PubMed:20719964). Ubiquitously expressed, with highest levels of expression detected in adipose tissue. Ubiquitinated; ubiquitination does not require ITCH and WWP1. The disease is caused by variants affecting the gene represented in this entry.