EMD-28007

Subtomogram averaging
20.0 Å
EMD-28007 Deposition: 31/08/2022
Map released: 15/03/2023
Last modified: 17/01/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-28007

Erwinia phage vB_EamM_RAY (RAY) Chimallin

EMD-28007

Subtomogram averaging
20.0 Å
EMD-28007 Deposition: 31/08/2022
Map released: 15/03/2023
Last modified: 17/01/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Erwinia phage vB_EamM_RAY
Sample: Erwinia phage vB_EamM_RAY (RAY) Chimallin
Raw data: EMPIAR-11198

Deposition Authors: Laughlin TG , Villa E
Identifying the core genome of the nucleus-forming bacteriophage family and characterization of Erwinia phage RAY.
PUBMED: 36865095
DOI: doi:10.1101/2023.02.24.529968
ISSN: 2692-8205
Abstract:
We recently discovered that some bacteriophages establish a nucleus-like replication compartment (phage nucleus), but the core genes that define nucleus-based phage replication and their phylogenetic distribution were unknown. By studying phages that encode the major phage nucleus protein chimallin, including previously sequenced yet uncharacterized phages, we discovered that chimallin-encoding phages share a set of 72 highly conserved genes encoded within seven distinct gene blocks. Of these, 21 core genes are unique to this group, and all but one of these unique genes encode proteins of unknown function. We propose that phages with this core genome comprise a novel viral family we term Chimalliviridae. Fluorescence microscopy and cryo-electron tomography studies of Erwinia phage vB_EamM_RAY confirm that many of the key steps of nucleus-based replication encoded in the core genome are conserved among diverse chimalliviruses, and reveal that non-core components can confer intriguing variations on this replication mechanism. For instance, unlike previously studied nucleus-forming phages, RAY doesn't degrade the host genome, and its PhuZ homolog appears to form a five-stranded filament with a lumen. This work expands our understanding of phage nucleus and PhuZ spindle diversity and function, providing a roadmap for identifying key mechanisms underlying nucleus-based phage replication.