Single-molecule imaging of Hedgehog pathway protein Smoothened in primary cilia reveals binding events regulated by Patched1.
Proc Natl Acad Sci U S A
; 112(27): 8320-5, 2015 Jul 07.
Article
de En
| MEDLINE
| ID: mdl-26100903
ABSTRACT
Accumulation of the signaling protein Smoothened (Smo) in the membrane of primary cilia is an essential step in Hedgehog (Hh) signal transduction, yet the molecular mechanisms of Smo movement and localization are poorly understood. Using ultrasensitive single-molecule tracking with high spatial/temporal precision (30 nm/10 ms), we discovered that binding events disrupt the primarily diffusive movement of Smo in cilia at an array of sites near the base. The affinity of Smo for these binding sites was modulated by the Hh pathway activation state. Activation, by either a ligand or genetic loss of the negatively acting Hh receptor Patched-1 (Ptch), reduced the affinity and frequency of Smo binding at the base. Our findings quantify activation-dependent changes in Smo dynamics in cilia and highlight a previously unknown step in Hh pathway activation.
Mots clés
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Cils vibratiles
/
Récepteurs de surface cellulaire
/
Récepteurs couplés aux protéines G
/
Protéines Hedgehog
Limites:
Animals
Langue:
En
Journal:
Proc Natl Acad Sci U S A
Année:
2015
Type de document:
Article