Institute of Metabolism and Systems Research (IMSR), and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham, UK.
Centre for Endocrinology, Diabetes and Metabolism, Birmingham Health Partners, Birmingham, UK.
Nat Commun. 2020 Jan 24;11(1):467. doi: 10.1038/s41467-020-14309-w.
The glucagon-like peptide-1 receptor (GLP1R) is a class B G protein-coupled receptor (GPCR) involved in metabolism. Presently, its visualization is limited to genetic manipulation, antibody detection or the use of probes that stimulate receptor activation. Herein, we present LUXendin645, a far-red fluorescent GLP1R antagonistic peptide label. LUXendin645 produces intense and specific membrane labeling throughout live and fixed tissue. GLP1R signaling can additionally be evoked when the receptor is allosterically modulated in the presence of LUXendin645. Using LUXendin645 and LUXendin651, we describe islet, brain and hESC-derived β-like cell GLP1R expression patterns, reveal higher-order GLP1R organization including membrane nanodomains, and track single receptor subpopulations. We furthermore show that the LUXendin backbone can be optimized for intravital two-photon imaging by installing a red fluorophore. Thus, our super-resolution compatible labeling probes allow visualization of endogenous GLP1R, and provide insight into class B GPCR distribution and dynamics both in vitro and in vivo.
胰高血糖素样肽-1 受体（GLP1R）是一种 B 类 G 蛋白偶联受体（GPCR），参与代谢。目前，其可视化仅限于遗传操作、抗体检测或使用刺激受体激活的探针。在此，我们提出了 LUXendin645，一种远红色荧光 GLP1R 拮抗肽标签。LUXendin645 在活组织和固定组织中产生强烈且特异性的膜标记。当受体在 LUXendin645 存在下被变构调节时，还可以引发 GLP1R 信号。使用 LUXendin645 和 LUXendin651，我们描述了胰岛、大脑和 hESC 衍生的β样细胞 GLP1R 的表达模式，揭示了包括膜纳米域在内的更高阶 GLP1R 组织，并且可以跟踪单个受体亚群。此外，我们还表明，可以通过安装红色荧光团来优化 LUXendin 骨架，以用于活体双光子成像。因此，我们的超分辨率兼容标记探针允许可视化内源性 GLP1R，并提供对 B 类 GPCR 分布和动力学的深入了解，无论是在体外还是体内。
