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bioRxiv · 10.1101/2021.07.20.453074

Remodeling of ryanodine receptor isoform 1 channel regulates the sweet and umami perception of Rattus norvegicus

Wang, W.·Lu, D.·Xu, Q.·Jin, Y.·Pang, G.·Liu, Y.
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Abstract

Sweet and umami are respectively elicited by sweet/umami receptor on the tongue and palate epithelium. However, the molecular machinery allowing to taste reaction remains incompletely understood. Through a phosphoproteomic approach, we found the key proteins that trigger taste mechanisms based on the phosphorylation cascades. Thereinto, ryanodine receptor isoform 1 (RYR1) was further verified by sensor and behaviors assay. A model proposing RYR1-mediated sweet/umami signaling: RYR1 channel which mediates Ca2+ release from the endoplasmic reticulum is closed by its dephosphorylation in the bud tissue after umami/sweet treatment. And the alteration of Ca2+ content in the cytosol induces a transient membrane depolarization and generates cell current for taste signaling transduction. We demonstrate that RYR1 is a new channel in regulation of sweet/umami signaling transduction and also propose a "metabolic clock" notion based on sweet/umami sensing. Our study provides a rich fundamental for a system-level understanding of taste perception mechanism.

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Wang, W., Lu, D., Xu, Q., Jin, Y., Pang, G., Liu, Y.. 2021-07-21. Remodeling of ryanodine receptor isoform 1 channel regulates the sweet and umami perception of Rattus norvegicus. https://doi.org/10.1101/2021.07.20.453074

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