Design and synthesis of a second-generation ligand-tethered calcium indicator for plant cell biology based on the fundamental analyses of the structure and physical property

Calcium ion (Ca²⁺) is one of the most important second messengers. However, conventional Ca²⁺ indicators cannot be applied in plant cells. In previous paper, we developed the first-generation protein-ligand tethered calcium indicator that can be applied for living plant cells. Here, we will report the development of second-generation indicator based on the detailed examination on physical properties of the first-generation to improve the drawbacks. Through the examination, we also found that cell permeability of the probe is strongly affected by their aggregation properties. Our findings will provide new strategy for the design of synthetic indicators.