Tag:CAAX(hKRAS) represents a CAAX prenylation motif (CVIM) derived from the 4B isoform of the Homo sapiens KRAS gene (HGNC:6407), where the polybasic domain normally found associated with this motif in KRAS is either not present or has been mutated to contain non-charged amino acids. When fused to the C-terminal end of a protein of interest, Tag:CAAX(hKRAS) results in the tagged protein being targeted to the endomembrane system (PMID:10412982, FBrf0212407).