Data from: Synergism, bifunctionality, and the evolution of a gradual sensory trade-off in hummingbird taste receptors

Sensory receptor evolution can imply trade-offs between ligands, but the
extent to which such trade-offs occur and the underlying processes shaping
their evolution is not well understood. For example, hummingbirds have
re-purposed their ancestral savory receptor (T1R1-T1R3) to detect sugars,
but the impact of this sensory shift on amino acid perception is unclear.
Here, we use functional and behavioral approaches to show that the
hummingbird T1R1-T1R3 acts as a bifunctional receptor responsive to both
sugars and amino acids. Our comparative analyses reveal substantial
functional diversity across the hummingbird radiation and suggest an
evolutionary timeline for T1R1-T1R3 re-tuning. Finally, we identify a
novel form of synergism between sugars and amino acids in vertebrate taste
receptors. This work uncovers an unexplored axis of sensory diversity,
suggesting new ways in which nectar chemistry and pollinator preferences
can coevolve.

感官感受器（sensory receptor）的演化往往伴随配体（ligand）间的权衡效应，但这类权衡的发生范围，以及塑造其演化的内在机制，目前仍未得到充分解析。例如，蜂鸟已将其祖先的鲜味感受器（savory receptor，T1R1-T1R3）重新改造以感知糖类，但这一感官转变对氨基酸感知的影响尚不明确。本研究通过功能学与行为学研究方法证实，蜂鸟的T1R1-T1R3属于双功能感受器，可同时响应糖类与氨基酸。我们的比较分析揭示了蜂鸟辐射演化类群间显著的功能多样性，并为T1R1-T1R3的重调谐演化提供了时间线线索。最后，我们在脊椎动物味觉感受器中发现了一种全新的糖类与氨基酸协同作用模式。本研究揭示了此前未被探索的感官多样性维度，为花蜜化学组成与传粉者偏好的协同演化提供了全新的研究视角。