Summary: For the first time, scientists have resolved the three-dimensional structure of the human sweet taste receptor, offering essential insight into how we sense sweetness and why sugar drives strong cravings. Using cryo-electron microscopy, researchers produced a detailed map showing how sweet molecules bind to the TAS1R2 component of the receptor, a region that functions like a Venus flytrap to capture sweet-tasting compounds.
This structural breakthrough could enable the rational design of new molecules that better regulate sweet taste signaling and reduce sugar cravings—an advance that may help address public health concerns such as obesity and diabetes. Unlike many existing artificial sweeteners, which were discovered by chance and often fail to curb our appetite for sugar, a structure-guided approach offers a direct path to improved sweeteners or modulators of taste.
Key Facts:
- Structural Breakthrough: The first high-resolution map of the human sweet taste receptor at approximately 2.8 angstrom resolution.
- Sweet Binding Pocket: The structure reveals the receptor’s binding cavity and how sweeteners such as sucralose and aspartame interact with it.
- Potential Applications: Structure-based design of better sugar substitutes, new taste modulators, and improved understanding of metabolic roles linked to taste receptors.
Source: Zuckerman Institute
Our attraction to sugar has increased dramatically. The average person in the United States now consumes more than 100 pounds of sugar each year, compared with about 18 pounds around 1800.
A study published May 7 in Cell by researchers at Columbia University’s Zuckerman Institute reports the first three-dimensional structure of the human sweet taste receptor. By revealing the receptor’s precise architecture, this work lays the groundwork for designing targeted compounds that could alter sweetness perception and help reduce excessive sugar intake.
The sweet taste receptor is the molecular machine on taste cells that allows us to detect sweet compounds. Understanding its shape is critical because the three-dimensional form determines which molecules can bind, how they trigger signaling, and how sensitive the receptor is to different stimuli.
More than two decades after the genes that encode the mammalian sweet receptor were discovered, this new study fills a major gap: researchers knew the receptor’s components but not their exact spatial arrangement. Without that structural information, designing molecules to specifically activate or inhibit the receptor has been difficult.
The research team, led by Charles Zuker, PhD, faced numerous technical challenges. It took roughly three years and more than 150 separate protein preparations to purify enough receptor for structural analysis. The investigators then used cryo-electron microscopy (cryo-EM) to capture frozen snapshots of the receptor bound to sweeteners and reconstruct its atomic-level structure.
Cryo-EM revealed the receptor’s binding pocket within the TAS1R2 subunit, a region that closes around sweet molecules much like a Venus flytrap. The team solved structures of the receptor bound to two widely used artificial sweeteners—sucralose and aspartame—compounds that are many times sweeter than sucrose. By comparing these structures and mutating small receptor elements, the researchers identified key residues that determine how different sweeteners attach and activate the receptor.
Study co-first authors Juen Zhang, PhD, and Zhengyuan Lu described how knowing the receptor’s exact shape opens possibilities to design new tastants or modulators that either mimic or block sweetness with greater precision. “The artificial sweeteners that we use today to replace sugar just don’t meaningfully change our desire for sugar,” said Dr. Zhang. “Now that we know what the receptor looks like, we might be able to design something better.”
Beyond the mouth, components of the sweet receptor are expressed in other tissues, including parts of the digestive tract and pancreas. That distribution suggests the receptor may influence metabolic processes, making the structural map valuable not only for taste science but also for research into metabolism and diseases such as diabetes.
By combining high-resolution structural data with functional experiments, the study provides a roadmap for developing next-generation sweeteners and taste modulators informed by the receptor’s physical form. Such rational design could reduce sugar cravings, improve nutritional choices, and contribute to public health strategies aimed at curbing diet-related disease.
About this neuroscience research news
Author: Zuckerman Communications
Source: Zuckerman Institute
Contact: Zuckerman Communications – Zuckerman Institute
Image: The image is credited to Neuroscience News
Original Research: Open access. “The Structure of Human Sweetness” by Andrew Chang et al., Cell. DOI: 10.1016/j.cell.2025.04.021
Abstract
The Structure of Human Sweetness
In humans, detection and perception of sweetness begin in the oral cavity, where taste receptor cells dedicated to sweet-sensing interact with sugars, artificial sweeteners, and other sweet-tasting chemicals. Human sweet taste receptor cells display a cell-surface receptor that initiates the signaling cascade responsible for our strong attraction to sweet stimuli.
Here, the authors describe the cryo-electron microscopy structure of the human sweet receptor bound to two widely used artificial sweeteners, sucralose and aspartame. These results reveal the structural basis for sweet detection, explain how a single receptor can recognize a wide variety of sweet compounds, and open unique possibilities for designing a new generation of taste modulators informed by the receptor’s structure.