KIFAP3 also known as SMAP, KAP3, Smg-GDS is a regulator protein having two activities on a group of small G proteins including the Rho and Rap1 family members. KIFAP3 plays a crucial role as an adaptor protein that facilitates the interaction between kinesin superfamily proteins and chromosome-associated proteins, which is essential for proper chromosome movement during cell division. KIFAP3′s ability to form ternary complexes with human chromosome-associated polypeptide (HCAP) and kinesin II proteins, KIF3A and KIF3B, underscores KIFAP3′s importance in maintaining chromosomal stability and ensuring accurate segregation during mitosis. Additionally, KIFAP3 is a substrate for tyrosine phosphorylation by v-Src, which may influence KIFAP3′s function and interactions within the cell.