Cholesterol accessibility at the ciliary membrane controls hedgehog signaling.
Elife
; 82019 10 30.
Article
en En
| MEDLINE
| ID: mdl-31657721
ABSTRACT
Previously we proposed that transmission of the hedgehog signal across the plasma membrane by Smoothened is triggered by its interaction with cholesterol (Luchetti et al., 2016). But how is cholesterol, an abundant lipid, regulated tightly enough to control a signaling system that can cause birth defects and cancer? Using toxin-based sensors that distinguish between distinct pools of cholesterol, we find that Smoothened activation and Hedgehog signaling are driven by a biochemically-defined, small fraction of membrane cholesterol, termed accessible cholesterol. Increasing cholesterol accessibility by depletion of sphingomyelin, which sequesters cholesterol in complexes, amplifies Hedgehog signaling. Hedgehog ligands increase cholesterol accessibility in the membrane of the primary cilium by inactivating the transporter-like protein Patched 1. Trapping this accessible cholesterol blocks Hedgehog signal transmission across the membrane. Our work shows that the organization of cholesterol in the ciliary membrane can be modified by extracellular ligands to control the activity of cilia-localized signaling proteins.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Transducción de Señal
/
Colesterol
/
Cilios
/
Proteínas Hedgehog
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Elife
Año:
2019
Tipo del documento:
Article
País de afiliación:
Estados Unidos