Structure of the immunoregulatory sialidase NEU1.
Gorelik, A., Illes, K., Mazhab-Jafari, M.T., Nagar, B.(2023) Sci Adv 9: eadf8169-eadf8169
- PubMed: 37205763 
- DOI: https://doi.org/10.1126/sciadv.adf8169
- Primary Citation of Related Structures:  
8DU5 - PubMed Abstract: 
Sialic acids linked to glycoproteins and glycolipids are important mediators of cell and protein recognition events. These sugar residues are removed by neuraminidases (sialidases). Neuraminidase-1 (sialidase-1 or NEU1) is a ubiquitously expressed mammalian sialidase located in lysosomes and on the cell membrane. Because of its modulation of multiple signaling processes, it is a potential therapeutic target for cancers and immune disorders. Genetic defects in NEU1 or in its protective protein cathepsin A (PPCA, CTSA) cause the lysosomal storage diseases sialidosis and galactosialidosis. To further our understanding of this enzyme's function at the molecular level, we determined the three-dimensional structure of murine NEU1. The enzyme oligomerizes through two self-association interfaces and displays a wide substrate-binding cavity. A catalytic loop adopts an inactive conformation. We propose a mechanism of activation involving a conformational change in this loop upon binding to its protective protein. These findings may facilitate the development of selective inhibitor and agonist therapies.
Organizational Affiliation: 
Department of Biochemistry, McGill University, Montreal, Quebec, Canada.