Next Article in Journal / Special Issue
Glycerophosphate/Acylglycerophosphate Acyltransferases
Previous Article in Journal
High Throughput Screening in Duchenne Muscular Dystrophy: From Drug Discovery to Functional Genomics
Previous Article in Special Issue
Genetic Risk Scores Associated with Baseline Lipoprotein Subfraction Concentrations Do Not Associate with Their Responses to Fenofibrate
Open AccessArticle

Cellular Localization and Trafficking of the Human ABCG1 Transporter

1
Lipoprotein Metabolism Section, Cardiovascular and Pulmonary Branch, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
2
Lipid Trafficking Core, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
3
NHLBI Light Microscopy Core Facility, National Institutes of Health, Bethesda, MD 20892, USA
*
Author to whom correspondence should be addressed.
Biology 2014, 3(4), 781-800; https://doi.org/10.3390/biology3040781
Received: 2 October 2014 / Revised: 23 October 2014 / Accepted: 28 October 2014 / Published: 14 November 2014
(This article belongs to the Special Issue Lipid Metabolism)
We have developed a suitable heterologous cell expression system to study the localization, trafficking, and site(s) of function of the human ABCG1 transporter. Increased plasma membrane (PM) and late endosomal (LE) cholesterol generated by ABCG1 was removed by lipoproteins and liposomes, but not apoA-I. Delivery of ABCG1 to the PM and LE was required for ABCG1-mediated cellular cholesterol efflux. ABCG1 LEs frequently contacted the PM, providing a collisional mechanism for transfer of ABCG1-mobilized cholesterol, similar to ABCG1-mediated PM cholesterol efflux to lipoproteins. ABCG1-mobilized LE cholesterol also trafficked to the PM by a non-vesicular pathway. Transfer of ABCG1-mobilized cholesterol from the cytoplasmic face of LEs to the PM and concomitant removal of cholesterol from the outer leaflet of the PM bilayer by extracellular acceptors suggests that ABCG1 mobilizes cholesterol on both sides of the lipid bilayer for removal by acceptors. ABCG1 increased uptake of HDL into LEs, consistent with a potential ABCG1-mediated cholesterol efflux pathway involving HDL resecretion. Thus, ABCG1 at the PM mobilizes PM cholesterol and ABCG1 in LE/LYS generates mobile pools of cholesterol that can traffic by both vesicular and non-vesicular pathways to the PM where it can also be transferred to extracellular acceptors with a lipid surface. View Full-Text
Keywords: ABCG1; cholesterol; cholesterol efflux; vesicular trafficking; HDL; rescretion ABCG1; cholesterol; cholesterol efflux; vesicular trafficking; HDL; rescretion
Show Figures

Graphical abstract

MDPI and ACS Style

Neufeld, E.B.; O'Brien, K.; Walts, A.D.; Stonik, J.A.; Demosky, S.J., Jr.; Malide, D.; Combs, C.A.; Remaley, A.T. Cellular Localization and Trafficking of the Human ABCG1 Transporter. Biology 2014, 3, 781-800.

Show more citation formats Show less citations formats

Article Access Map by Country/Region

1
Only visits after 24 November 2015 are recorded.
Search more from Scilit
 
Search
Back to TopTop