ATP modulates SLC7A5 (LAT1) synergistically with cholesterol

Author(s)
Jessica Cosco, Mariafrancesca Scalise, Claire Colas, Michele Galluccio, Riccardo Martini, Filomena Rovella, Tiziano Mazza, Gerhard F Ecker, Cesare Indiveri
Abstract

The plasma membrane transporter hLAT1 is responsible for providing cells with essential amino acids. hLAT1 is over-expressed in virtually all human cancers making the protein a hot-spot in the fields of cancer and pharmacology research. However, regulatory aspects of hLAT1 biology are still poorly understood. A remarkable stimulation of transport activity was observed in the presence of physiological levels of cholesterol together with a selective increase of the affinity for the substrate on the internal site, suggesting a stabilization of the inward open conformation of hLAT1. A synergistic effect by ATP was also observed only in the presence of cholesterol. The same phenomenon was detected with the native protein. Altogether, the biochemical assays suggested that cholesterol and ATP binding sites are close to each other. The computational analysis identified two neighboring regions, one hydrophobic and one hydrophilic, to which cholesterol and ATP were docked, respectively. The computational data predicted interaction of the ϒ-phosphate of ATP with Lys 204, which was confirmed by site-directed mutagenesis. The hLAT1-K204Q mutant showed an impaired function and response to ATP. Interestingly, this residue is conserved in several members of the SLC7 family.

Organisation(s)
External organisation(s)
Università della Calabria, National Research Council of Italy (CNR)
Journal
Scientific Reports
Volume
10
Pages
16738
ISSN
2045-2322
DOI
https://doi.org/10.1038/s41598-020-73757-y
Publication date
10-2020
Peer reviewed
Yes
Austrian Fields of Science 2012
104004 Chemical biology
Portal url
https://ucris.univie.ac.at/portal/en/publications/atp-modulates-slc7a5-lat1-synergistically-with-cholesterol(3f233c7a-43a8-44b6-a77b-320089565162).html