The goal of this project is to elucidate the molecular mechanisms underlying the functions of apolipoprotein (apo) A-I in reverse cholesterol transport (RCT). Apo A-I is the major protein of plasma high density lipoprotein (HDL) and the functions of this molecule underlie the anti-atherogenic properties of this lipoprotein.
Specific Aim 1 is to define the domains of apo A-I critical for the binding of phospholipid (PL) and the assembly of various types of HDL particles; this is significant because the ways in which apo A-I participates in RCT depend upon its state of lipidation. The structure-function relationships of apo A-I will be examined using protein molecules altered by mutagenesis.
Specific Aim 2 is to define the molecular events involved in the """"""""membrane micro-solubilization"""""""" process by which lipid-poor apo A-I (pre-beta-HDL) removes unesterified cholesterol and PL from the plasma membrane of cells.
Specific Aim 3 is to elucidate the behavior of apo A-I as a ligand for the scavenger-receptor (SR)-B1 receptor and the molecular mechanism of the selective uptake into cells of cholesteryl ester mediated by the binding of HDL to this receptor. The lipid-binding capabilities of plasma apo A-I, engineered apo A-I and model peptides will be determined using a range of physical-biochemical techniques. The functional domains of apo A-I involved in mediating cholesterol and lipid transport at cell surfaces will be defined by using various engineered apo A-I molecules in cell culture systems. The results of this project will provide greater understanding of the mechanisms by which HDL protects against premature coronary artery disease.
Showing the most recent 10 out of 336 publications
