Sweet taste receptor signaling bias research for optimizing sweetener palatability

Overview

This research program investigates the role of signaling bias downstream of the sweet taste receptor (STR), specifically focusing on how arrestin-mediated pathways and their interplay with G protein signaling regulate hedonic responses to both caloric sugars and non-caloric sweeteners. The core premise is that arrestins and G proteins trigger partially independent signaling pathways downstream of G protein-coupled receptors such as the STR, often with opposing effects. By understanding this dynamic interplay, the research aims to develop novel strategies to optimize the use of non-caloric sweeteners and sugars in the diet, potentially uncoupling desirable sweet taste from undesirable side effects such as off-tastes or lingering sweetness.

Technical specifications

Key research findings and capabilities:

• Arrestin conditional knockout (CKO) mice exhibit strikingly low behavioral attraction to sweet and umami tastants compared to wild-type littermates
• Single-cell RNA sequencing data identified arrestin gene co-expression with the STR subunit Tas1r3 in circumvallate and fungiform papillae, confirmed by fluorescent double-label immunohistochemistry and RNAScope assays
• Brief access taste tests demonstrate reduced attraction to multiple sweet tastants, including caloric sugars, non-caloric sweeteners, and umami stimuli, while responses to bitter, salty, and sour stimuli remain largely unchanged
• Newly developed polarity-reversed taste organoids enable repeated stimulation with tastants for biochemical analysis
• Planned characterization of STR signaling includes calcium mobilization, arrestin-mediated MAP kinase activation, arrestin-STR interaction, and STR endocytosis and adaptation
• Organoids will be engineered to express human STR to assess responses to sweeteners not detected by mice, such as sweet proteins

Technology readiness level

This research is at an early-to-mid stage of discovery, with foundational findings already established through knockout mouse models and gene expression analyses. Future validation will expand behavioral testing across all known sweetener chemical classes and conduct detailed biochemical characterization using novel organoid systems. The program is positioned to generate intellectual property and scientific insights that could benefit food and beverage companies seeking to improve sweetener formulations, with potential applications in sweetener development, taste optimization, and food product formulation.