+Search query
-Structure paper
| Title | Mechanistic adaptation of the metazoan RabGEFs Mon1-Ccz1 and Fuzzy-Inturned. |
|---|---|
| Journal, issue, pages | Sci Adv, Vol. 11, Issue 35, Page eadx2893, Year 2025 |
| Publish date | Aug 29, 2025 |
Authors | Stephan Wilmes / Jesse Tönjes / Maik Drechsler / Anita Ruf / Jan-Hannes Schäfer / Anna Lürick / Dovile Januliene / Steven Apelt / Daniele Di Iorio / Seraphine V Wegner / Martin Loose / Arne Moeller / Achim Paululat / Daniel Kümmel / ![]() |
| PubMed Abstract | Rab GTPases organize intracellular trafficking and provide identity to organelles. Their spatiotemporal activation by guanine nucleotide exchange factors (GEFs) is tightly controlled to ensure ...Rab GTPases organize intracellular trafficking and provide identity to organelles. Their spatiotemporal activation by guanine nucleotide exchange factors (GEFs) is tightly controlled to ensure fidelity. Our structural and functional comparison of the tri-longin domain RabGEFs Mon1-Ccz1 and Fuzzy-Inturned reveals the molecular basis for their target specificity. Both complexes rely on a conserved sequence motif of their substrate GTPases for the catalytic mechanism, while secondary interactions allow discrimination between targets. We also find that dimeric Mon1-Ccz1 from fungi and the metazoan homologs with the additional third subunit RMC1/Bulli bind membranes through electrostatic interactions via distinct interfaces. Protein-lipid interaction studies and functional characterization in flies reveal an essential function of RMC1/Bulli as mediator of GEF complex membrane recruitment. In the case of Fuzzy-Inturned, reconstitution experiments demonstrate that the BAR (Bin-Amphiphysin-Rvs) domain protein CiBAR1 can support membrane recruitment of the GEF. Collectively, our study demonstrates the molecular basis for the adaptation of TLD-RabGEFs to different cellular functions. |
External links | Sci Adv / PubMed:40864718 / PubMed Central |
| Methods | EM (single particle) |
| Resolution | 3.0 - 3.7 Å |
| Structure data | EMDB-54211, PDB-9rs6: EMDB-54212, PDB-9rs7: EMDB-54213, PDB-9rs8: EMDB-54214, PDB-9rs9: |
| Source |
|
Keywords | CYTOSOLIC PROTEIN / longin domain / GEF / nucleotide exchange / endosome / autophagosome / small GTPase |
Movie
Controller
Structure viewers
About Yorodumi Papers



Authors

External links







thermochaetoides thermophila (fungus)
homo sapiens (human)
Keywords