| Type: | Domain | Name: | Bacteriophage RNA-type, capsid |
| Description: | This entry represents capsid coat proteins from a variety of RNA bacteriophages, including Bacteriophage MS2, Bacteriophage GA, Bacteriophage fr, Bacteriophage Q-betaand Pseudomonas phage PP7. These capsid coat proteins share a similar structure, consisting of a 6-stranded beta-sheet followed by two helices. Capsid proteins form the bacteriophage coat that encapsidates the viral RNA. In Bacteriophage MS2, 180 copies of this protein form the virion shell and control two distinct processes: sequence-specific RNA encapsidation and repression of replicase translation by binding to an RNA stem-loop structure of 19 nucleotides containing the initiation codon of the replicase gene. The binding of a coat protein dimer to this hairpin shuts off synthesis of the viral replicase, switching the viral replication cycle to virion assembly rather than continued replication []. | Short Name: | Phage_RNA-type_capsid |
