8RUY

Structure of IFTA and IFTB in Retrograde Intraflagellar transport trains

This is a non-PDB format compatible entry.

Summary for 8RUY

• Entry DOI: 10.2210/pdb8ruy/pdb
• EMDB information: 19515
• Descriptor: Intraflagellar transport protein 144, Intraflagellar transport protein 27, Intraflagellar transport protein 25, ... (20 entities in total)
• Functional Keywords: cilia, ift, train, retrograde, protein transport
• Biological source: Chlamydomonas reinhardtii; More
• Total number of polymer chains: 30
• Total formula weight: 2357509.11

Authors

Lacey, S.,Pigino, G. (deposition date: 2024-01-31, release date: 2024-07-24, Last modification date: 2025-08-06)

Primary citation

Lacey, S.E.,Graziadei, A.,Pigino, G.
Extensive structural rearrangement of intraflagellar transport trains underpins bidirectional cargo transport.
Cell, 187:4621-4636.e18, 2024

PubMed Abstract: Bidirectional transport in cilia is carried out by polymers of the IFTA and IFTB protein complexes, called anterograde and retrograde intraflagellar transport (IFT) trains. Anterograde trains deliver cargoes from the cell to the cilium tip, then convert into retrograde trains for cargo export. We set out to understand how the IFT complexes can perform these two directly opposing roles before and after conversion. We use cryoelectron tomography and in situ cross-linking mass spectrometry to determine the structure of retrograde IFT trains and compare it with the known structure of anterograde trains. The retrograde train is a 2-fold symmetric polymer organized around a central thread of IFTA complexes. We conclude that anterograde-to-retrograde remodeling involves global rearrangements of the IFTA/B complexes and requires complete disassembly of the anterograde train. Finally, we describe how conformational changes to cargo-binding sites facilitate unidirectional cargo transport in a bidirectional system.

PubMed: 39067443
DOI: 10.1016/j.cell.2024.06.041

Experimental method

ELECTRON MICROSCOPY (15.4 Å)