Holian O, Kumar R, Attar B
Department of Surgery, University of Illinois College of Medicine, Chicago 60680.
Biochem Biophys Res Commun. 1991 Aug 30;179(1):599-604. doi: 10.1016/0006-291x(91)91413-7.
Apoprotein A-1 (apo A-1), the predominant protein constituent of high density lipoproteins (HDL), was phosphorylated by protein kinase C (PKC). Optimal phosphorylation of lipid-free apo A-1 occurs in the absence of calcium, phosphatidyl serine (PS), and diolein (DO). However, HDL-bound apo A-1 was not phosphorylated by PKC. Furthermore, addition of either native or reconstituted HDL particles to lipid-free apo A-1 resulted in a concentration-dependent inhibition of phosphorylation. It appears that the phosphorylatable sites on apo A-1 are involved in hydrophobic interaction with the lipids of HDL. Apo A-1 is a novel substrate of PKC because it does not require calcium and lipid cofactors for optimal phosphorylation.
载脂蛋白A-1（apo A-1）是高密度脂蛋白（HDL）的主要蛋白质成分，可被蛋白激酶C（PKC）磷酸化。无脂apo A-1的最佳磷酸化发生在无钙、磷脂酰丝氨酸（PS）和二油精（DO）的情况下。然而，与HDL结合的apo A-1不会被PKC磷酸化。此外，向无脂apo A-1中添加天然或重组HDL颗粒会导致磷酸化受到浓度依赖性抑制。看来apo A-1上的可磷酸化位点参与了与HDL脂质的疏水相互作用。Apo A-1是PKC的一种新型底物，因为它在最佳磷酸化时不需要钙和脂质辅因子。
