ABCA7 links sterol metabolism to the host defense system: Molecular background for potential management measure of Alzheimer's disease.

ABCA7 links sterol metabolism to the host defense system: Molecular background for potential management measure of Alzheimer's disease. Gene. 2020 Nov 19;:145316 Authors: Abe-Dohmae S, Yokoyama S Abstract ATP-binding cassette transporter (ABC) A7 is a membrane protein that belongs to the large family of ABC transporters. It is 54 % homologous in amino acid residue sequence to ABCA1 which mediates biogenesis of plasma high density lipoprotein (HDL) from cellular phospholipid and cholesterol with extracellular helical apolipoproteins such as apolipoprotein (apo) A-I. When transfected and expressed, ABCA7 also mediates generation of HDL-like particles but small and of less cholesterol content. However, endogenous ABCA7 is unlikely involved in HDL biogenesis and rather to regulate the host-defense system such as phagocytotic function of the cells. ABCA1 expression is regulated by cellular cholesterol levels, positively by the liver X receptor (LXR) in extrahepatic peripheral cells. However, it is modulated dually in the liver being relevant to transport of cholesterol for its catabolism; positively by LXR and negatively by sterol regulatory element binding protein (SREBP) or hepatic nuclear factor 4α (HNF4α). In contrast, ABCA7 expression was shown to be regulated negatively by the SREBP system so that decrease of cell cholesterol enhances ABCA7 function such as cellular phagocytotic reaction, suggesting that it links cholesterol metab...
Source: Gene - Category: Genetics & Stem Cells Authors: Tags: Gene Source Type: research