G-protein-coupled receptors (GPCRs) are the largest human receptor family and involved in virtually every physiological process. One hallmark of their function is specific coupling to selected signaling pathways. The ability to tune this coupling would make development of receptors with new capabilities possible. Complexes of GPCRs and G-proteins have recently been resolved at high resolution, but this information was in only few cases harnessed for rational receptor engineering. Here, we demonstrate structure-guided optimization of light-activated OptoXRs. Our hypothesis was that incorporation of GPCR-Gα contacts would lead to improved coupling. We first evaluated structure-based alignments for chimeric receptor fusion. We then show in a light-activated β₂AR that including Gα contacts increased signaling 7- to 20-fold compared with other designs. In turn, contact elimination diminished function. Finally, this platform allowed optimization of a further OptoXR and spectral tuning. Our work exemplifies structure-based OptoXR development for targeted cell and network manipulation.

G 蛋白偶联受体 (GPCRs) 是最大的人类受体家族，几乎参与所有生理过程。它们功能的一个标志是与选定的信号通路的特定耦合。调整这种耦合的能力将使开发具有新能力的受体成为可能。GPCRs 和 G 蛋白的复合物最近已经以高分辨率解析，但该信息仅在少数情况下被用于合理的受体工程。在这里，我们展示了光激活 OptoXR 的结构引导优化。我们的假设是 GPCR-Gα 接触的结合会导致耦合的改善。我们首先评估了嵌合受体融合的基于结构的比对。然后我们展示了一个光激活的 β ₂与其他设计相比，包括 Gα 接触的 AR 信号增加了 7 到 20 倍。反过来，接触消除削弱了功能。最后，该平台允许进一步优化 OptoXR 和光谱调谐。我们的工作举例说明了针对目标细胞和网络操作的基于结构的 OptoXR 开发。