Is ABCA1 a lipid transfer protein?
J Lipid Res
; 59(5): 749-763, 2018 05.
Article
in En
| MEDLINE
| ID: mdl-29305383
ABSTRACT
ABCA1 functions as a lipid transporter because it mediates the transfer of cellular phospholipid (PL) and free (unesterified) cholesterol (FC) to apoA-I and related proteins present in the extracellular medium. ABCA1 is a membrane PL translocase and its enzymatic activity leads to transfer of PL molecules from the cytoplasmic leaflet to the exofacial leaflet of a cell plasma membrane (PM). The presence of active ABCA1 in the PM promotes binding of apoA-I to the cell surface. About 10% of this bound apoA-I interacts directly with ABCA1 and stabilizes the transporter. Most of the pool of cell surface-associated apoA-I is bound to lipid domains in the PM that are created by the activity of ABCA1. The amphipathic α-helices in apoA-I confer detergent-like properties on the protein enabling it to solubilize PL and FC in these membrane domains to create a heterogeneous population of discoidal nascent HDL particles. This review focuses on current understanding of the structure-function relationships of human ABCA1 and the molecular mechanisms underlying HDL particle production.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
ATP Binding Cassette Transporter 1
Limits:
Humans
Language:
En
Journal:
J Lipid Res
Year:
2018
Document type:
Article