+Search query
-Structure paper
Title | SepN is a septal junction component required for gated cell-cell communication in the filamentous cyanobacterium Nostoc. |
---|---|
Journal, issue, pages | Nat Commun, Vol. 13, Issue 1, Page 7486, Year 2022 |
Publish date | Dec 5, 2022 |
Authors | Ann-Katrin Kieninger / Piotr Tokarz / Ana Janović / Martin Pilhofer / Gregor L Weiss / Iris Maldener / |
PubMed Abstract | Multicellular organisms require controlled intercellular communication for their survival. Strains of the filamentous cyanobacterium Nostoc regulate cell-cell communication between sister cells via a ...Multicellular organisms require controlled intercellular communication for their survival. Strains of the filamentous cyanobacterium Nostoc regulate cell-cell communication between sister cells via a conformational change in septal junctions. These multi-protein cell junctions consist of a septum spanning tube with a membrane-embedded plug at both ends, and a cap covering the plug on the cytoplasmic side. The identities of septal junction components are unknown, with exception of the protein FraD. Here, we identify and characterize a FraD-interacting protein, SepN, as the second component of septal junctions in Nostoc. We use cryo-electron tomography of cryo-focused ion beam-thinned cyanobacterial filaments to show that septal junctions in a sepN mutant lack a plug module and display an aberrant cap. The sepN mutant exhibits highly reduced cell-cell communication rates, as shown by fluorescence recovery after photobleaching experiments. Furthermore, the mutant is unable to gate molecule exchange through septal junctions and displays reduced filament survival after stress. Our data demonstrate the importance of controlling molecular diffusion between cells to ensure the survival of a multicellular organism. |
External links | Nat Commun / PubMed:36470860 / PubMed Central |
Methods | EM (subtomogram averaging) / EM (tomography) |
Resolution | 21.0 - 51.0 Å |
Structure data | EMDB-16012: Subtomogram average of septal junctions from Nostoc PCC 7120 in the open state EMDB-16033: Subtomogram average of septal junctions from Nostoc PCC 7120 in the closed state EMDB-16034: Subtomogram average of septal junctions from sepN mutant EMDB-16053: Subtomogram average of septal junctions from sepN-sfgfp mutant EMDB-16054: Subtomogram average of septal junctions from sepN-mbp-sfgfp mutant EMDB-16061: Electron cryotomogram of septal region from FIB milled filament of Nostoc sp. PCC 7120 sepN-mbp-sfgfp mutant |
Source |
|