Cryo-EM reveals cholesterol binding in the lysosomal GPCR-like protein LYCHOS

Nat Struct Mol Biol. 2025 May;32(5):896-904. doi: 10.1038/s41594-024-01470-9. Epub 2025 Jan 17.

Abstract

Cholesterol plays a pivotal role in modulating the activity of mechanistic target of rapamycin complex 1 (mTOR1), thereby regulating cell growth and metabolic homeostasis. LYCHOS, a lysosome-localized G-protein-coupled receptor-like protein, emerges as a cholesterol sensor and is capable of transducing the cholesterol signal to affect the mTORC1 function. However, the precise mechanism by which LYCHOS recognizes cholesterol remains unknown. Here, using cryo-electron microscopy, we determined the three-dimensional structural architecture of LYCHOS in complex with cholesterol molecules, revealing a unique arrangement of two sequential structural domains. Through a comprehensive analysis of this structure, we elucidated the specific structural features of these two domains and their collaborative role in the process of cholesterol recognition by LYCHOS.

MeSH terms

  • Cholesterol* / chemistry
  • Cholesterol* / metabolism
  • Cryoelectron Microscopy
  • Humans
  • Lysosomes* / metabolism
  • Models, Molecular
  • Protein Binding
  • Receptors, G-Protein-Coupled* / chemistry
  • Receptors, G-Protein-Coupled* / metabolism
  • Receptors, G-Protein-Coupled* / ultrastructure

Substances

  • Cholesterol
  • Receptors, G-Protein-Coupled