ADP Ribosylation Factor Like Protein 5B (ARL5B)

ARL8 belongs to a family of proteins that are structurally similar to ADP-ribosylation factors (ARFs). ARLs and ARFs are part of the RAS superfamily of regulatory GTPases. The deduced 179-amino acid protein contains sequences conserved in other ARLs, including those that bind Mg(2+) and others involved in GTP binding and hydrolysis. ARL8 is most related to ARL5, with which it shares 80% amino acid identity. ARL8 shares 100% identity with mouse Arl8 and 71% identity with the Drosophila homolog. Northern blot analysis detected a 6.7-kb mouse Arl8 transcript in brain, heart, lung, cartilage, and kidney, but not in spleen. An alternate 8.7-kb transcript was detected in postnatal mouse brain, but not in adult mouse brain. Northern blot analysis detected weak expression of human ARL8 in brain, but not in spleen.