Apolipoprotein B /ApoB [APOB/3300]

Post-transcriptional editing of Apolipoprotein B (ApoB) mRNA is regulated byAPOBEC1 (also designated human (or rat) small intestinal apolipoprotein BmRNA editing protein, HEPR or REPR) in hepatic cells to achieve a steadystate proportion of edited and unedited RNA molecules. Two forms of apoBare known to circulate in the plasma of mammals. ApoB-100 is a proteinprimarily synthesized in the liver as a structural component of very low densitylipoprotein particles. A truncated form of apoB-100, apoB-48, is synthesizedin the small intestine and contains the amino-terminal 2,152 amino acids ofthe larger protein. This organ-specific partitioning of apoB production is theresultof RNA editing of a common apoB gene.