Apolipoproteins are protein components of plasma lipoproteins. APOM is a member of the lipocalin family of proteins. APOM is exclusively expressed in kidney tubular epithelial cells and liver hepatocytes. APOM is secreted through the plasma membrane but remains membrane-bound, where it is involved in lipid transport. It is important for the formation of prebeta-HDL and cholesterol efflux to HDL, and thereby inhibits formation of atherosclerotic lesions. The concentration of APOM in plasma strongly correlates with total cholesterol. Low concentrations of APOM in plasma are associated with diabetes. Recombinant human APOM protein was expressed in E.coli and purified by using conventional chromatography techniques. Synonyms: G3a, HSPC336, NG20, Apolipoprotein M Apo M, ApoM, G3A, MGC22400, NG20 like protein, Protein G3a. NCBI no.: NP_061974