改进的基因编码的钙指标(GECI)对于捕获肌肉和神经元的细胞内动力学至关重要。Zhang等人最近报道了一套具有超快动力学和高灵敏度的新型GECIs。(自然,2023年)。而这些指标,被称为jGCaMP8,被证明在果蝇和小鼠中起作用,未报告秀丽隐杆线虫的数据.这里,我们提出了一种用于C.elegans的优化构建体,并使用它来产生表达GCaMP8f(指示剂的快速变体)的几种菌株。利用myo-2启动子,我们比较了用GCaMP7f和GCaMP8f测得的咽肌活动,发现GCaMP8f与钙结合后更亮,显示更快的动力学,并且不会破坏咽部的固有收缩动力学。此外,我们验证了其在触摸受体神经元中检测神经元活动的应用,即使在小的刺激幅度下也能显示出强大的钙瞬变。因此,我们建立了GCaMP8f作为C.elegans研究的有效工具,它能够在多种细胞类型中以非常低的放大倍数提取快速的钙动力学。
Improved genetically-encoded calcium indicators (GECIs) are essential for capturing intracellular dynamics of both muscle and neurons. A novel set of GECIs with ultra-fast kinetics and high sensitivity was recently reported by Zhang et al. (Nature, 2023). While these indicators, called jGCaMP8, were demonstrated to work in Drosophila and mice, data for Caenorhabditis elegans were not reported. Here, we present an optimized construct for C. elegans and use this to generate several strains expressing GCaMP8f (fast variant of the indicator). Utilizing the myo-2 promoter, we compare pharyngeal muscle activity measured with GCaMP7f and GCaMP8f and find that GCaMP8f is brighter upon binding to calcium, shows faster kinetics and is not disruptive to the intrinsic contraction dynamics of the pharynx. Additionally, we validate its application for detecting neuronal activity in touch receptor neurons which reveals robust calcium transients even at small stimulus amplitudes. As such, we establish GCaMP8f as a potent tool for C. elegans research which is capable of extracting fast calcium dynamics at very low magnifications across multiple cell types.