1. ATP-Binding Cassette (ABC) Transporter:
Cholesterol Trafficking on Cell Membranes

     Cardiovascular disease (CVD) is currently the leading cause of death around the world, and the hyperlipidemia can lead to atherosclerosis, the main CVD cause. The ABC sterol/lipid transporters control cholesterol trafficking on the cellular membranes, and their deficiency causes atherosclerosis, hypertriglyceridemia, and impaired high-density lipoprotein.

     To understand how lipid transporters regulate lipid homeostasis and respond to systemic lipid levels, we study the function-structure relationship of the ABC lipid transporters using subfamilies G and A (ABCG and ABCA) members as the model system.

2. Type IV P-type (P4)-ATPase:
Membrane Phospholipid Transport

     Active lipid transport is a process by which cells harness ATP energy to translocate lipids within the lipid bilayers, and key to maintain the structural integrity of mosaic lipid bilayers and to provide lipid substrates for various cellular functions.

 

     Type-IV P-Type ATPases (P4-ATPases), a major eukaryotic transport ATPase family, carry out cellular phospholipid transport by flipping substrates from one leaflet to the other leaflet of the membrane bilayers. They are associated with phospholipid asymmetry across membranes, stimulation of programmed cell death (also known as apoptosis), and intracellular vesicle trafficking and formation. Our research program aims at elucidating the molecular details underlying the catalysis-coupled lipid recognition and translocation by ATP-dependent lipid-transport membrane proteins.