The ciliary lumen accommodates passive diffusion and vesicle-assisted trafficking in cytoplasm-ciliary transport.

ABSTRACT: Transport of membrane and cytosolic proteins into the primary cilium is essential for its role in cellular signaling. Using virtual three-dimensional superresolution light microscopy, the movements of membrane and soluble proteins from the cytoplasm to the primary cilium were mapped. In addition to the well-characterized intraflagellar transport (IFT) route, we found two new pathways within the lumen of the primary cilium: passive diffusion and vesicle-assisted transport routes that are adopted by proteins for cytoplasm-cilium transport in live cells. Through these pathways, approximately half of IFT motors (KIF3A) and cargo (α-tubulin) take the passive diffusion route, and more than half of membrane-embedded G protein-coupled receptors (SSTR3 and HTR6) use RAB8A-regulated vesicles to tran

SUBMITTER: Ruba A 

PROVIDER: S-EPMC10208104 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature