Apolipoproteins are protein components of plasma lipoproteins. The apolipoprotein L gene family encodes six highly homologous proteins designated apoL-I to -VI, which are associated with large high density type lipoproteins (HDL). The human apoL family maps to chromosome 22q12.1- 13.1 within a 127,000-bp region . apoL has been characterized as a pancreas specific, 383-amino acid, 42 kDa protein that contains a 12-amino acid secretory signal peptide. The apoL genes have TATA-less promoters and contain putative sterol regulatory elements, suggesting that transcription of these genes may be coordinated with that of the low density lipoprotein receptor and genes in pathways involving the synthesis of triglycerides and cholesterol. apoL homologs can undergo 10 fold changes in expression during atherosclerotic changes in vascular endothelial cells, which includes the inflammatory reaction of atherosclerotic lesions.
