C16orf44 is a 616 amino acid protein that contains six Kelch repeats, one BTB/POZ domain and one BTB/Kelch associated (BACK) domain. C16orf44 is believed to play a role in protein ubiquitination and may function as a substrate-specific adapter of an E3 ubiquitin-protein ligase complex. E3 ligases accept a ubiquitin residue from an E2 ubiquitin-conjugating enzyme and immediately transfer that residue to a protein that is targeted for degradation. Specifically, C16orf44 interacts with CUL-3, a member of the cullin family of mediators that participate in the selective targeting of proteins for ubiquitin-mediated proteolysis. Due to alternative splicing events, two isoforms of C16orf44 are expressed.