Purity: > 90% by SDS - PAGE Format: Liquid. In Phosphate buffered saline (pH7.4), 30% glycerol, 1mM DTT. RAB39B is a member of the Rab family of proteins. Rab proteins are small GTPases that are involved in vesicular trafficking. Mutations in this gene are associated with X-linked mental retardation. Recombinant human RAB39B protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.