RAB22A, also known as ras-related protein Rab-22A, is a member of the RAB family of small GTPases. The GTP-bound form of the encoded protein has been shown to interact with early-endosomal antigen 1, and may be involved in the trafficking of and interaction between endosomal compartments. Recombinant human RAB22A protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography.