8XYB
hPhK gamma-delta subcomplex in inactive state
Summary for 8XYB
| Entry DOI | 10.2210/pdb8xyb/pdb |
| EMDB information | 36215 |
| Descriptor | Phosphorylase b kinase regulatory subunit alpha, skeletal muscle isoform, Calmodulin-1, Phosphorylase b kinase gamma catalytic chain, skeletal muscle/heart isoform, ... (4 entities in total) |
| Functional Keywords | glycogen phosphorylase b kinase, gamma-delta subcomplex, muscle isoform, inactive state, cytosolic protein |
| Biological source | Homo sapiens (human) More |
| Total number of polymer chains | 3 |
| Total formula weight | 199613.01 |
| Authors | Yang, X.K.,Xiao, J.Y. (deposition date: 2024-01-19, release date: 2024-04-03, Last modification date: 2024-04-10) |
| Primary citation | Yang, X.,Zhu, M.,Lu, X.,Wang, Y.,Xiao, J. Architecture and activation of human muscle phosphorylase kinase. Nat Commun, 15:2719-2719, 2024 Cited by PubMed Abstract: The study of phosphorylase kinase (PhK)-regulated glycogen metabolism has contributed to the fundamental understanding of protein phosphorylation; however, the molecular mechanism of PhK remains poorly understood. Here we present the high-resolution cryo-electron microscopy structures of human muscle PhK. The 1.3-megadalton PhK αβγδ hexadecamer consists of a tetramer of tetramer, wherein four αβγδ modules are connected by the central β scaffold. The α- and β-subunits possess glucoamylase-like domains, but exhibit no detectable enzyme activities. The α-subunit serves as a bridge between the β-subunit and the γδ subcomplex, and facilitates the γ-subunit to adopt an autoinhibited state. Ca-free calmodulin (δ-subunit) binds to the γ-subunit in a compact conformation. Upon binding of Ca, a conformational change occurs, allowing for the de-inhibition of the γ-subunit through a spring-loaded mechanism. We also reveal an ADP-binding pocket in the β-subunit, which plays a role in allosterically enhancing PhK activity. These results provide molecular insights of this important kinase complex. PubMed: 38548794DOI: 10.1038/s41467-024-47049-2 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (3.1 Å) |
Structure validation
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