|
|
||||||||
Short Communication |
1 Centre for Biomolecular Sciences, School of Biology, Biomolecular Sciences Building, University of St Andrews, North Haugh, St Andrews KY16 9ST, UK
2 Institute of Poliomyelitis and Viral Encephalitides, Russian Academy of Medical Sciences, Moscow 142782, Russia
Correspondence
Martin D. Ryan
martin.ryan{at}st-and.ac.uk
2A is an oligopeptide sequence mediating a ribosome skipping effect, producing an apparent cleavage of polyproteins. First identified and characterized in picornaviruses, 2A-like sequences are found in other mammalian viruses and a wide range of insect viruses. Databases were analysed using a motif conserved amongst 2A/2A-like sequences. The newly identified 2A-like sequences (30 aa) were inserted into a reporter polyprotein to determine their cleavage activity. Our analyses showed that these sequences fall into two categories. The majority mediated very high (complete) cleavage to separate proteins and a few sequences mediated cleavage with lower efficiency, generating appreciable levels of the uncleaved form. Phylogenetic analyses of 2A-like sequences and RNA-dependent RNA polymerases (RdRps) indicated multiple, independent, acquisitions of these sequences at different stages during virus evolution. Within a virus family, 2A sequences are (probably) homologous, but diverge due to other evolutionary pressures. Amongst different families, however, 2A/2A-like sequences appear to be homoplasic.
Supplementary material is available with the online version of this paper.
This article has been cited by other articles:
![]() |
B. Zhao, A. Song, R. Haque, F. Lei, L. Weiler, X. Xiong, Y. Wu, M. Croft, and J. Song Cooperation between Molecular Targets of Costimulation in Promoting T Cell Persistence and Tumor Regression J. Immunol., June 1, 2009; 182(11): 6744 - 6752. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Tang, W. F. Ochoa, R. S. Sinkovits, B. T. Poulos, S. A. Ghabrial, D. V. Lightner, T. S. Baker, and M. L. Nibert Infectious myonecrosis virus has a totivirus-like, 120-subunit capsid, but with fiber complexes at the fivefold axes PNAS, November 11, 2008; 105(45): 17526 - 17531. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. A. Doronina, C. Wu, P. de Felipe, M. S. Sachs, M. D. Ryan, and J. D. Brown Site-Specific Release of Nascent Chains from Ribosomes at a Sense Codon Mol. Cell. Biol., July 1, 2008; 28(13): 4227 - 4239. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| INT J SYST EVOL MICROBIOL | MICROBIOLOGY | J GEN VIROL |
| J MED MICROBIOL | ALL SGM JOURNALS | |