Tian Xiaodong, Zhang Yiyu, Du Haoyang, Huang Wenyuan, Bizimana Laurie Anne, Nishimura Nozomi, Ai Hui-Wang
Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia 22908, United States.
Center for Membrane and Cell Physiology, University of Virginia School of Medicine, Charlottesville, Virginia 22908, United States.
ACS Sens. 2025 Aug 22;10(8):5826-5833. doi: 10.1021/acssensors.5c01093. Epub 2025 Jul 29.
Calcium (Ca) is a crucial metal ion and signaling messenger. While bioluminescent indicators for Ca have emerged as powerful imaging tools, their performance has been suboptimal. In this study, we developed an nhanced ioluminescent red ndicator for a (eBRIC) by using a physiological Ca concentration range during library screening. Compared with its predecessors, this new sensor demonstrates substantially improved Ca responsiveness in protein-based assays, cultured cell lines, and primary neurons. We further demonstrated the utility of eBRIC for the in vivo recording of Ca dynamics in the brains of live mice, using both a microscope setup and a luminescent imaging dark box. Notably, by combining eBRIC with our recently developed water-soluble luciferin, we achieved minimally invasive, video-rate imaging of Ca activity in a defined brain region of awake mice. In a footshock-induced basolateral amygdala activation paradigm, eBRIC elicited approximately double the response compared to the previous BRIC indicator. The improved responsiveness offered by eBRIC underscores its potential as a powerful tool for investigating Ca dynamics in living systems.
钙（Ca）是一种至关重要的金属离子和信号信使。虽然用于钙的生物发光指示剂已成为强大的成像工具，但其性能一直不尽人意。在本研究中，我们在文库筛选过程中利用生理钙浓度范围开发了一种用于钙的增强型生物发光红色指示剂（eBRIC）。与之前的指示剂相比，这种新型传感器在基于蛋白质的检测、培养的细胞系和原代神经元中表现出显著改善的钙响应性。我们还进一步证明了eBRIC在活体小鼠大脑中钙动力学的体内记录中的实用性，使用了显微镜装置和发光成像暗箱。值得注意的是，通过将eBRIC与我们最近开发的水溶性荧光素相结合，我们在清醒小鼠的特定脑区实现了对钙活性的微创、视频速率成像。在足底电击诱导的基底外侧杏仁核激活范式中，与之前的BRIC指示剂相比，eBRIC引发的反应大约是其两倍。eBRIC提供的改进响应性突出了其作为研究活体系统中钙动力学的强大工具的潜力。
