A Hyperthermophilic Phage Decoration Protein Suggests Common Evolutionary Origin with Herpesvirus Triplex Proteins and an Anti-CRISPR Protein
AuthorsStone, Nicholas P.
Hilbert, Brendan J.
Halloran, Kevin T.
Sontheimer, Erik J.
Kelch, Brian A.
UMass Chan AffiliationsGraduate School of Biomedical Sciences, Program in Biochemistry and Molecular Pharmacology
RNA Therapeutics Institute
Department of Biochemistry and Molecular Pharmacology
capsid decoration protein
double-stranded DNA virus
Biochemistry, Biophysics, and Structural Biology
Genetics and Genomics
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AbstractVirus capsids are protein shells that protect the viral genome from environmental assaults, while maintaining the high internal pressure of the tightly packaged genome. To elucidate how capsids maintain stability under harsh conditions, we investigated the capsid components of the hyperthermophilic phage P74-26. We determined the structure of capsid protein gp87 and show that it has the same fold as decoration proteins in many other phages, despite lacking significant sequence homology. We also find that gp87 is significantly more stable than mesophilic homologs. Our analysis of the gp87 structure reveals that the core "beta tulip" domain is conserved in trimeric capsid components across numerous double-stranded DNA viruses, including Herpesviruses. Moreover, this beta barrel domain is found in anti-CRISPR protein AcrIIC1, suggesting a mechanism for the evolution of this Cas9 inhibitor. Our work illustrates the principles for increased stability of gp87, and extends the evolutionary reach of the beta tulip domain.
Structure. 2018 Jul 3;26(7):936-947.e3. doi: 10.1016/j.str.2018.04.008. Epub 2018 May 17. Link to article on publisher's site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/48853
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