Biology subjects

Heuninck, J.

Publications and source records attributed to Heuninck, J..

2 recordsLinked to original sources

bioRxiv2023

Membrane lipid poly-unsaturation selectively affects ligand induced dopamine D2 receptor internalization

The brain is highly enriched in poly-unsaturated fatty acids (PUFAs) and their deficiency has been associated with several neuropsychiatric disorders. Here, we demonstrate that the Dopamine receptor D2 (D2R), a class A G protein coupled receptor (GPCR) which is a main target of antipsychotics, displays unique sensitivity to membrane PUFA composition. We found that membrane enrichment with either of two distinct PUFAs significantly impairs agonist-induced D2R endocytosis in HEK-293 cells and cortical neurons. This treatment does not affect clathrin-mediated endocytosis or the internalization of several other GPCRs. Moreover, we show that D2R clustering at endocytic pits is not affected, but that recruitment of {beta}-arrestin2 is strongly impaired and endocytic vesicle formation is slowed down. Finally, mutation of key residues in intracellular loop 2 abolishes the sensitivity of D2R endocytosis to PUFA enrichment. We conclude that D2R trafficking is uniquely dependent on membrane PUFAs, which could influence its role in the control of brain function and behavior.

cell biology↗

bioRxiv2021

Mechanisms of GPCR hijacking by Staphylococcus aureus

Atypical chemokine receptor 1 (ACKR1) is a G protein-coupled receptor (GPCR) targeted by Staphylococcus aureus (SA) bi-component pore-forming leukotoxins to promote bacterial growth and immune evasion. Here we have developed an integrative molecular pharmacology and structural biology approach in order to characterize the effect of leukotoxins HlgA and HlgB on ACKR1 structure and function. Interestingly, we found that both components HlgA and HlgB compete with endogenous chemokines through a direct binding to ACKR1 captured by native mass spectrometry (MS). Unexpectedly, HDX-MS analysis revealed that toxin binding allosterically modulates the intracellular G protein-binding domain of the receptor, resulting in dissociation of ACKR1-G protein complexes in living cells. Altogether, our study brings important molecular insights into the initial steps of leukotoxins targeting a host GPCR. Our findings may open the way to develop antibiotics inhibiting host receptors binding, a mechanism of action less prone to resistance.

biochemistry↗