| description | Virion protein that constitutes the noncontractile ejection system carried by some short-tailed prokaryotic viruses such as some Podoviridae. This ejection system is composed at least of the tail tube and ejection proteins. Upon receptor binding, proteins located inside the capsid (head) rearrange to extend the tail tube, creating a channel spanning the periplasmic space. This hydrophilic channel directs the viral genome, and possibly some specific proteins, into the cytoplasm and protects it from periplasmic nucleases. Once the viral genome is in the host cytoplasm, the channel collapses and seals. Bacteriophage T7 for example expresses ejection proteins that partition into the host outer and cytoplasmic membranes and allow transport of viral DNA across the host envelope. Proteins of the ejection apparatus can play an active or a structural role in ejection |
Ontology Term --> All ancestors
Ontology Term --> All descendants
Ontology Term --> Direct children
Ontology Term --> Direct parents
