Confirmation of the phosphorylation sites of human PhK

The activity of PhK is regulated by phosphorylation, and we utilized single-particle cryo-electron microscopy to solve the high-resolution structures of human PhK under phosphorylation and calcium ion activation. To gain a deeper insight into the phosphorylation sites following PKA treatment, we employed tandem mass spectrometry for precise localization of the phosphorylation sites within PhK.