Rab-like protein 5 isoform a, also known as RABL5, is a member of the Ras superfamily of small GTP-binding proteins. The Ras-related superfamily of guanine nucleotide binding proteins includes the R-Ras, Rap, Ral/Rec and Rho/Rab subfamilies. Increasing data suggests an important role for Rab proteins in either endocytosis or in biosynthetic protein transport. The process of transporting newly synthesized proteins from the endoplasmic reticulum to various stacks of the Golgi complex and to secretory vesicles involves the movement of carrier vesicles and requires Rab protein function. Recombinant human RABL5 protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.