Anti-VARP ANKRD27 Antibody

The VPS9 ankyrin repeat protein (VARP) binds to the Rab21, a guanine nucleotide exchange factor that plays an essential role in endocytic trafficking. VARP localizes to early endosomes and is thought to regulate endosome dynamics. VARP also interacts with TI-VAMP/VAMP7, a vesicular SNARE that mediates an exocytic pathway that is crucial to neurite growth. Depletion of VARP by RNA interference impairs neurite growth, suggesting that VARP is a positive regulator of neurite growth.

VARP antibody was raised against a 16 amino acid synthetic peptide near the amino terminus of human VARP. The immunogen is located within amino acids 50 - 100 of VARP.

May be a guanine exchange factor (GEF) for Rab21, Rab32 and Rab38 and regulate endosome dynamics (PubMed:16525121, PubMed:18477474) . May regulate the participation of VAMP7 in membrane fusion events; in vitro inhibits VAMP7-mediated SNARE complex formation by trapping VAMP7 in a closed, fusogenically inactive conformation (PubMed:23104059) . Involved in peripheral melanosomal distribution of TYRP1 in melanocytes; the function, which probably is implicating vesicle-trafficking, includes cooperation with Rab32, Rab38 and VAMP7 (By similarity) . Involved in the regulation of neurite growth; the function seems to require its GEF activity, probably towards Rab21, and VAMP7 but not Rab32/38 (By similarity) . Proposed to be involved in Golgi sorting of VAMP7 and transport of VAMP7 vesicles to the cell surface; the function seems to implicate kinesin heavy chain isoform 5 proteins, GOLGA4, RAB21 and MACF1 (PubMed:22705394) . Required for the colocalization of VAMP7 and Rab21, probably on TGN sites (PubMed:19745841) . Involved in GLUT1 endosome-to-plasma membrane trafficking; the function is dependent of association with VPS29 (PubMed:24856514) . Regulates the proper trafficking of melanogenic enzymes TYR, TYRP1 and DCT/TYRP2 to melanosomes in melanocytes (By similarity) .

VARP antibody can be stored at 4°C for three months and -20°C, stable for up to one year. Avoid repeated freeze-thaw cycles. Antibodies should not be exposed to prolonged high temperatures.