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Shui, W.

Publications and source records attributed to Shui, W..

5 recordsLinked to original sources

Cell membrane proteome profiling uncovers molecular signatures and GPCR regulators underlying diet-induced obesity and exercise-mediated adaptation

Cell membrane proteins (CMPs), notably G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs), represent the largest class of druggable targets. Despite their therapeutic importance, how the CMP landscape is systemically remodeled during metabolic disease progression and in response to exercise remains poorly understood. Here, we constructed the most comprehensive CMP proteome atlas to date across 22 male mouse tissues and established the first multi-tissue map of GPCR-associated protein hormones/prohormones. Integrated CMP proteomic and transcriptomic analysis revealed that diet-induced obesity and its progression to type 2 diabetes remodel the CMP repertoire in patterns distinct from those induced by exercise. We found that numerous GPCRs and RTKs critical for energy homeostasis are dysregulated during obesity in a tissue-specific manner, and these alterations are reversed to varying extents by exercise training. Importantly, our CMP-centric omics study identified two parathyroid hormone receptors (PTHRs) in the hypothalamus as negative regulators of feeding and body weight. Genetically silencing these hypothalamic PTHRs led to severe obesity even on a chow diet and markedly blunted exercise-induced weight loss. Collectively, our study provides not only new insights into systematic CMP regulation underlying metabolic deterioration versus exercise adaptation, but also nominates potential receptor targets for obesity management.

biochemistry↗

Post-translational modifications orchestrate the intrinsic signaling bias of orphan receptor GPR52

Despite recent advances in GPCR structure and pharmacology, the regulation of GPCR activation, signaling, and functioning by diverse post-translational modifications (PTMs) has been largely unexplored. Furthermore, for a special category of self-activating orphan GPCRs, it is completely unknown whether and how specific PTMs control their unique signaling profiles and cellular functions. In this study of GPR52, an orphan GPCR with exceedingly high constitutive G protein signaling activity and emerging as a neurotherapeutic target, we discovered its disproportionately low arrestin recruitment activity. Through profiling the N-glycosylation and phosphorylation patterns of the receptor and clarifying their roles in G protein versus arrestin coupling, we found these two types of PTMs in specific motifs differentially shape the intrinsic signaling bias of GPR52. While N-terminal N-glycosylation promotes constitutive Gs signaling possibly through favoring the self-activating conformation, phosphorylation in helix 8, to our great surprise, suppresses arrestin recruitment and thus attenuates receptor internalization. In addition, we uncovered the counteracting roles of N-glycosylation and phosphorylation in modulating GPR52-dependent accumulation of the huntingtin protein (HTT) in brain striatal cells. Thus, our study provides novel insights into the regulation of intrinsic signaling bias and cellular function of an orphan GPCR via distinct PTMs in different motifs.

cell biology↗

Organized cannabinoid receptor distribution in neurons revealed by super-resolution fluorescence imaging

G-protein-coupled receptors (GPCRs) play important roles in cellular functions. However, their intracellular organization is largely unknown. Through investigation of the cannabinoid receptor 1 (CB1), we discovered periodically repeating clusters of CB1 hotspots within the axons of neurons. We observed these CB1 hotspots interact with the membrane-associated periodic skeleton (MPS) forming a complex crucial in the regulation of CB1 signaling. Furthermore, we found that CB1 hotspot periodicity increased upon CB1 agonist application, and these activated CB1 displayed less dynamic movement compared to non-activated CB1. Our results suggest that CB1 forms periodic hotspots organized by the MPS as a mechanism to increase signaling efficacy when being activated.

neuroscience↗

A hybrid spectral library combining DIA-MS data and a targeted virtual library substantially deepens the proteome coverage

Data-independent acquisition mass spectrometry (DIA-MS) is a rapidly evolving technique that enables relatively deep proteomic profiling with superior quantification reproducibility. DIA data mining predominantly relies on a spectral library of sufficient proteome coverage that, in most cases, is built on data-dependent acquisition-based analysis of the same sample. To expand the proteome coverage for a pre-determined protein family, we report herein on the construction of a hybrid spectral library that supplements a DIA experiment-derived library with a protein family-targeted virtual library predicted by deep learning. Leveraging this DIA hybrid library substantially deepens the coverage of three transmembrane protein families (G protein coupled receptors; ion channels; and transporters) in mouse brain tissues with increases in protein identification of 37-87%, and peptide identification of 58-161%. Moreover, of the 412 novel GPCR peptides exclusively identified with the DIA hybrid library strategy, 53.6% were validated as present in mouse brain tissues based on orthogonal experimental measurement.

bioinformatics↗

A novel G protein-biased and subtype selective agonist for a G protein-coupled receptor discovered from screening herbal extracts

Subtype selectivity and functional bias are vital in current drug discovery for G protein-coupled receptors (GPCRs) as selective and biased ligands are expected to yield drug leads with optimal on-target benefits and minimal side-effects. However, structure-based design and medicinal chemistry exploration remain challenging in part because of highly conserved binding pockets within subfamilies. Herein, we present an affinity mass spectrometry approach for screening herbal extracts to identify active ligands of a GPCR, the 5-HT2C receptor. Using this method, we discovered a naturally occurring aporphine 1857 that displayed strong selectivity for activating 5-HT2C without activating the 5-HT2A or 5-HT2B receptors. Remarkably, this novel ligand exhibited exclusive bias towards G protein signaling for which key residues were identified, and it showed comparable in vivo efficacy for food intake suppression and weight loss as the anti-obesity drug, lorcaserin. Our study establishes an efficient approach to discovering novel GPCR ligands by exploring the largely untapped chemical space of natural products.

biochemistry↗