Download MendeleyTRPML2 in distinct states reveals the activation and modulation principles of the TRPML family.
Schmiege, P., Jaslan, D., Fine, M., Sadanandan, N.P., Hatton, A., Elghobashi-Meinhardt, N., Grimm, C., Li, X.(2025) Nat Commun 16: 5325-5325
- PubMed: 40527873
- DOI: https://doi.org/10.1038/s41467-025-60710-8
- Primary Citation of Related Structures:
9EKS, 9EKT, 9EKU, 9EKV, 9EKW, 9EKX, 9EKY, 9EKZ, 9EL0, 9EL1 - PubMed Abstract:
TRPML2 activity is critical for endolysosomal integrity and chemokine secretion, and can be modulated by various ligands. Interestingly, two ML-SI3 isomers regulate TRPML2 oppositely. The molecular mechanism underlying this unique isomeric preference as well as the TRPML2 agonistic mechanism remains unknown. Here, we present six cryo-EM structures of human TRPML2 in distinct states revealing that the π-bulge of the S6 undergoes a π-α transition upon agonist binding, highlighting the remarkable role of the π-bulge in ion channel regulation. Moreover, we identify that PI(3,5)P 2 allosterically affects the pose of ML2-SA1, a TRPML2 specific activator, resulting in an open channel without the π-α transition. Functional and structural studies show that mutating the S5 of TRPML1 to that of TRPML2 enables the mutated TRPML1 to be activated by (+)ML-SI3 and ML2-SA1. Thus, our work elucidates the activation mechanism of TRPML channels and paves the way for the development of selective TRPML modulators.
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
Organizational Affiliation:
