2. Academic Validation
  3. Molecular basis for the regulation of human phosphorylase kinase by phosphorylation and Ca2

Molecular basis for the regulation of human phosphorylase kinase by phosphorylation and Ca2

  • Nat Commun. 2025 Mar 28;16(1):3020. doi: 10.1038/s41467-025-58363-8.
Ruifang Ma # 1,  Bowen Du # 1,  Chen Shi # 2 3,  Lei Wang 1,  Fuxing Zeng 4 5,  Jie Han 1,  Huiyi Guan 1,  Yong Wang 6 7,  Kaige Yan 8 9
Affiliations

Affiliations

  • 1 Shenzhen Key Laboratory of Biomolecular Assembling and Regulation, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China.
  • 2 College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
  • 3 Department of Engineering Mechanics, Zhejiang University, Hangzhou, 310027, China.
  • 4 Department of Systems Biology, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China.
  • 5 Institute for Biological Electron Microscopy, Southern University of Science and Technology, Shenzhen, 518055, China.
  • 6 College of Life Sciences, Zhejiang University, Hangzhou, 310058, China. yongwang_isb@zju.edu.cn.
  • 7 The Provincial International Science and Technology Cooperation Base on Engineering Biology, International Campus of Zhejiang University, Haining, 314499, China. yongwang_isb@zju.edu.cn.
  • 8 Shenzhen Key Laboratory of Biomolecular Assembling and Regulation, School of Life Sciences, Southern University of Science and Technology, Shenzhen, 518055, China. yankg@sustech.edu.cn.
  • 9 Institute for Biological Electron Microscopy, Southern University of Science and Technology, Shenzhen, 518055, China. yankg@sustech.edu.cn.
  • # Contributed equally.
PMID: 40148320 DOI: 10.1038/s41467-025-58363-8
Abstract

Phosphorylase kinase (PhK) regulates the degradation of glycogen by integrating diverse signals, providing energy to the organism. Dysfunctional mutations may directly lead to Glycogen Storage Disease type IX (GSD IX), whereas the abnormal expression of PhK is also associated with tumors. Here, we use cryo-electron microscopy (cryo-EM) to resolve its near-atomic structures in the inactive and active states. These structures reveal the interactions and relative locations of the four subunits (αβγδ) within the PhK complex. Phosphorylated α and β subunits induce PhK to present a more compact state, while CA2+ causes sliding of the δ subunit along the helix of the γ subunit. Both actions synergistically activate PhK by enabling the de-inhibition of the γ subunit. We also identified different binding modes between PhK and its substrate, glycogen Phosphorylase (GP), in two distinct states, using cross-linking mass spectrometry (XL-MS). This study provides valuable insights into the regulatory mechanisms of PhK, thereby enhancing our understanding of GSD IX and its implications in tumorigenesis.

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