Anti-RAB38 Antibody

Members of the Rab family of small GTPases direct intracellular vesicle transport, and the 24 kDa RAB38 protein is a defining member of the Rab32/Rab38 subfamily that controls trafficking of melanogenic enzymes to maturing melanosomes. It localizes to perinuclear vesicles and end-stage melanosomes in pigment-producing cells, where it coordinates the post-Golgi delivery of tyrosinase, TYRP1, and TYRP2. Loss-of-function alleles define two classical disease models: the "chocolate" (cht) mouse, which carries a G19V substitution that abolishes prenylation and leaves the protein cytosolic and unstable, and the Ruby rat, a recognized model of Hermansky-Pudlak syndrome featuring oculocutaneous albinism, prolonged bleeding, and abnormal surfactant homeostasis.

This polyclonal reagent from Antibodies.com is raised in rabbit and purified as an IgG preparation, supplied unconjugated in a 200 µl liquid aliquot. It has been validated for Western blot detection of endogenous RAB38 in human, mouse, and rat samples, where it recognizes a band near the predicted 24 kDa molecular weight. The unconjugated format makes the reagent straightforward to pair with HRP-, fluorescent-, or biotin-conjugated secondary antibodies chosen by the user.

RAB38 is most highly expressed in alveolar type II cells, melanocytes, and platelets, the three cell types that contain characteristic lysosome-related organelles (lamellar bodies, melanosomes, and dense granules). Published biochemistry shows that RAB38 and its close paralog RAB32 act downstream of the BLOC-3 guanine nucleotide exchange factor, recruit the VARP effector to control VAMP7 recycling on the melanosome membrane, and engage BLOC-2 plus the AP-3 adaptor complex to deliver cargo to maturing melanosomes. Disrupting these pathways produces the giant lamellar bodies and surfactant overloading seen in chocolate mice and Ruby rats, phenotypes that closely resemble the pulmonary fibrosis observed in human HPS-1, HPS-2, and HPS-4 patients. Researchers use this antibody to compare LRO biogenesis between wild-type and mutant rodent lines, to characterize melanocyte and retinal pigment epithelium cultures, and to survey RAB38 expression in idiopathic pulmonary fibrosis tissue panels.

For best results, store the vial at -20 °C in working aliquots and limit freeze-thaw cycles to preserve IgG integrity. Brief centrifugation before opening recovers the full volume.