载脂蛋白AI( apolipoprotein A-I,apoA-I)是高密度脂蛋白( high-density lipoprotein ,HDL)的主要蛋白成分,其中两性α-螺旋是apoA-I相应功能的结构基础。 ApoA-I 分子N-端是动态的四螺旋束结构,C-端形成无规则的螺旋结构,是介导蛋白质与磷脂结合的功能域。两分子apoA-I呈反向平行的双带结构环绕磷脂双分子层形成圆盘状HDL,而球状HDL表面的apoA-I分子则形成三叶草结构。 ATP结合盒转运蛋白 A1(ATP-binding cassette transporter A1,ABCA1)介导apoA-I与磷脂及胆固醇相互作用形成新生HDL,参与胆固醇的逆向转运过程。 ApoA-I、HDL作为抗动脉粥样硬化的主要作用靶标,深入了解其分子结构与功能、构象变化和相互作用及其影响脂质代谢平衡的机制对抗动脉粥样硬化药物的研发及其应用具有重要意义。
Apolipoprotein AI ( apoA-I ) is the major protein component of high-density lipoprotein ( HDL) ,and apoA -I can stabilize the structure of HDL .Whereas the amphipathic αh-elix is the structur -al motif for apoA-I to complete the corresponding functionality .In the lipid-free state, the N-terminal of apoA-I molecule is a dynamic four-helix bundle structure , most amino acid residues of the C-terminal do-main is the formation of a disordered structure , which is the initial domain that mediates bingding to phos-pholipid surface .Two molecules of apoA-I are arranged in an anti-parallel , double-belt conformation a-round the surface of the discoidal HDL particles .However , the apoA-I molecule forms a trefoil scaffold structure , which can adapt to the surface of spherical HDL particles .ATP-binding cassette transporter A 1 ( ABCA1) can mediate phospholipid and cholesterol efflux from intracellular and interact with apoA -I to generate nascent HDL particles .Overall, apoA-I and HDL as an anti-atherosclerotic effect of primary tar-get, we focus on the molecular structure of apoA-I, which determines the structure and function of differ-ent size of HDL particles , as well as the conformational changes after interaction with lipids , in order to learn more about the relationship of apolipoprotein and lipids metabolism against atherosclerosis .