Involved in the negative regulation of fatty acid biosynthesis, probably acting as an adapter that allows ubiquitination of acetyl-CoA carboxylase 1 (ACACA) by E3 ubiquitin-protein ligase COP1, and promotes ACACA degradation (PubMed:39920308). The adapter function requires the C-terminal proline-rich domain and may be apart from the kinesin motor activity (Probable). . This is the function of KIF12 (kinesin family member 12, Ensembl gene identifier ENSG00000136883).