5MUU

dsRNA bacteriophage phi6 nucleocapsid

Summary for 5MUU

• Entry DOI: 10.2210/pdb5muu/pdb
• EMDB information: 3571
• Descriptor: Major inner protein P1, Packaging enzyme P4, Major outer capsid protein (3 entities in total)
• Functional Keywords: icosahedral virus capsid shell, virus
• Biological source: Pseudomonas phage phi6; More
• Total number of polymer chains: 13
• Total formula weight: 365544.03

Authors

Sun, Z.,El Omari, K.,Sun, X.,Ilca, S.L.,Kotecha, A.,Stuart, D.I.,Poranen, M.M.,Huiskonen, J.T. (deposition date: 2017-01-14, release date: 2017-03-22, Last modification date: 2024-05-15)

Primary citation

Sun, Z.,El Omari, K.,Sun, X.,Ilca, S.L.,Kotecha, A.,Stuart, D.I.,Poranen, M.M.,Huiskonen, J.T.
Double-stranded RNA virus outer shell assembly by bona fide domain-swapping.
Nat Commun, 8:14814-14814, 2017

PubMed Abstract: Correct outer protein shell assembly is a prerequisite for virion infectivity in many multi-shelled dsRNA viruses. In the prototypic dsRNA bacteriophage φ6, the assembly reaction is promoted by calcium ions but its biomechanics remain poorly understood. Here, we describe the near-atomic resolution structure of the φ6 double-shelled particle. The outer T=13 shell protein P8 consists of two alpha-helical domains joined by a linker, which allows the trimer to adopt either a closed or an open conformation. The trimers in an open conformation swap domains with each other. Our observations allow us to propose a mechanistic model for calcium concentration regulated outer shell assembly. Furthermore, the structure provides a prime exemplar of bona fide domain-swapping. This leads us to extend the theory of domain-swapping from the level of monomeric subunits and multimers to closed spherical shells, and to hypothesize a mechanism by which closed protein shells may arise in evolution.

PubMed: 28287099
DOI: 10.1038/ncomms14814

Experimental method

ELECTRON MICROSCOPY (4 Å)