FunctionInhibits lipoprotein lipase and hepatic lipase and decreases the uptake of lymph chylomicrons by hepatic cells. This suggests that it delays the catabolism of triglyceride-rich particles.
Tissue specificityConstitutes 50% of the protein fraction of VLDL and 2% of that of HDL. Synthesized predominantly in liver and to a lesser degree in intestine.
Involvement in diseaseDefects in APOC3 may be a cause of hyperalphalipoproteinemia (HYPALIP) [MIM:143470]. Affected individuals show high levels of alpha-lipoprotein (high density lipoprotein/HDL).
Sequence similaritiesBelongs to the apolipoprotein C3 family.
Post-translational modificationsO-linked glycan consists of Gal-GalNAc disaccharide, further modified with up to 3 sialic acid residues. O-glycosylated on Thr-94 with a core 1 or possibly core 8 glycan.