MyJournals Home  

RSS FeedsS-acylation modulates the function of the apical sodium-dependent bile acid transporter in human cells [Membrane Biology] (Journal of Biological Chemistry)


4 april 2020 03:00:17

S-acylation modulates the function of the apical sodium-dependent bile acid transporter in human cells [Membrane Biology] (Journal of Biological Chemistry)

The ileal apical sodium-dependent bile acid transporter (ASBT) is crucial for the enterohepatic circulation of bile acids. ASBT function is rapidly regulated by several posttranslational modifications. One reversible posttranslational modification is S-acylation, involving the covalent attachment of fatty acids to cysteine residues in proteins. However, whether S-acylation affects ASBT function and membrane expression has not been determined. Using the acyl resin-assisted capture method, we found that the majority of ASBT (~80%) was S-acylated in ileal brush border membrane vesicles from human organ donors, as well as in HEK293 cells stably transfected with ASBT (2BT cells). Metabolic labeling with alkyne-palmitic acid (100 ?m for 15 h) also showed that ASBT is S-acylated in 2BT cells. Incubation with the acyltransferase inhibitor 2-bromopalmitate (25 ?m for 15 h) significantly reduced ASBT S-acylation, function, and levels on the plasma membrane. Treatment of 2BT cells with saturated palmitic acid (100 ?m for 15 h) increased ASBT function, whereas treatment with unsaturated oleic acid significantly reduced ASBT function. Metabolic labeling with alkyne-oleic acid (100 ?m for 15 h) revealed that oleic acid attaches to ASBT, suggesting that unsaturated fatty acids may decrease ASBT`s function via a direct covalent interaction with ASBT. We also identified Cys-314 as a potential S-acylation site. In conclusion, these results provide evidence that S-acylation is involved in the modulation of ASBT function. These findings underscore the potential for unsaturated fatty acids to reduce ASBT function, which may be useful in disorders in which bile acid toxicity is implicated.

16 viewsCategory: Biochemistry
The hydrolysis mechanism of a GH45 cellulase and its potential relation to lytic transglycosylase and expansin function [Computational Biology] (Journal of Biological Chemistry)
The two splice variant forms of Cdc42 exert distinct and essential functions in neurogenesis [Cell Biology] (Journal of Biological Chemistry)
blog comments powered by Disqus
The latest issues of all your favorite science journals on one page


Register | Retrieve



Copyright © 2008 - 2020 Indigonet Services B.V.. Contact: Tim Hulsen. Read here our privacy notice.
Other websites of Indigonet Services B.V.: Nieuws Vacatures News Tweets Nachrichten