Glycogen phosphorylase kinase (PhK) initiates glycogen degradation by phosphorylating glycogen phosphorylase (GP), positioning itself at the core of glycogenolysis. Here, the authors utilize cryo-EM to elucidate the mechanisms by which human PhK is regulated by phosphorylation and calcium ions, and reveal its binding mode with the substrate GP.
- Ruifang Ma
- Bowen Du
- Kaige Yan