Anti-TBC1D3I antibodies are used in the immunodetection of the protein TBC1 domain family member 3I. In humans, the canonical protein has a reported length of 549 amino acid residues and a mass of 62.2 kDa. Its subcellular localization is in the cell membrane. It is notably expressed in the testis. TBC1D3I is known to act as a GTPase activating protein for RAB5. Post-translational modifications have been described, including ubiquitination and palmitoylation. Synonyms for this target antigen include Protein TRE17-alpha, Rab GTPase-activating protein PRC17, TBC1 domain family member-like, and Prostate cancer gene 17 protein.