Once the homeostasis of potassium, sodium, and chloride in human cells is out of balance, it will lead to a series of diseases such as hypertension, depression, and epilepsy. At the cell membrane, there is a class of proteins known as cation-chloride cotransporters that effectively regulate ion homeostasis in the cell. The group of Guo Jiangtao of Zhejiang University School of Medicine solved the 2.9-Å high-resolution cryo-EM structure of a…