PMID- 23043113
OWN - NLM
STAT- MEDLINE
DCOM- 20130107
LR  - 20211021
IS  - 1091-6490 (Electronic)
IS  - 0027-8424 (Print)
IS  - 0027-8424 (Linking)
VI  - 109
IP  - 43
DP  - 2012 Oct 23
TI  - Efficient -2 frameshifting by mammalian ribosomes to synthesize an additional 
      arterivirus protein.
PG  - E2920-8
LID - 10.1073/pnas.1211145109 [doi]
AB  - Programmed -1 ribosomal frameshifting (-1 PRF) is a gene-expression mechanism 
      used to express many viral and some cellular genes. In contrast, efficient 
      natural utilization of -2 PRF has not been demonstrated previously in eukaryotic 
      systems. Like all nidoviruses, members of the Arteriviridae (a family of 
      positive-stranded RNA viruses) express their replicase polyproteins pp1a and 
      pp1ab from two long ORFs (1a and 1b), where synthesis of pp1ab depends on -1 PRF. 
      These polyproteins are posttranslationally cleaved into at least 13 functional 
      nonstructural proteins. Here we report that porcine reproductive and respiratory 
      syndrome virus (PRRSV), and apparently most other arteriviruses, use an 
      additional PRF mechanism to access a conserved alternative ORF that overlaps the 
      nsp2-encoding region of ORF1a in the +1 frame. We show here that this ORF is 
      translated via -2 PRF at a conserved G_GUU_UUU sequence (underscores separate 
      ORF1a codons) at an estimated efficiency of around 20%, yielding a transframe 
      fusion (nsp2TF) with the N-terminal two thirds of nsp2. Expression of nsp2TF in 
      PRRSV-infected cells was verified using specific Abs, and the site and direction 
      of frameshifting were determined via mass spectrometric analysis of nsp2TF. 
      Further, mutagenesis showed that the frameshift site and an unusual 
      frameshift-stimulatory element (a conserved CCCANCUCC motif 11 nucleotides 
      downstream) are required to direct efficient -2 PRF. Mutations preventing nsp2TF 
      expression impair PRRSV replication and produce a small-plaque phenotype. Our 
      findings demonstrate that -2 PRF is a functional gene-expression mechanism in 
      eukaryotes and add another layer to the complexity of arterivirus genome 
      expression.
FAU - Fang, Ying
AU  - Fang Y
AD  - Departments of Veterinary and Biomedical Science and Biology/Microbiology, South 
      Dakota State University, Brookings, SD 57007, USA. ying.fang@sdstate.edu
FAU - Treffers, Emmely E
AU  - Treffers EE
FAU - Li, Yanhua
AU  - Li Y
FAU - Tas, Ali
AU  - Tas A
FAU - Sun, Zhi
AU  - Sun Z
FAU - van der Meer, Yvonne
AU  - van der Meer Y
FAU - de Ru, Arnoud H
AU  - de Ru AH
FAU - van Veelen, Peter A
AU  - van Veelen PA
FAU - Atkins, John F
AU  - Atkins JF
FAU - Snijder, Eric J
AU  - Snijder EJ
FAU - Firth, Andrew E
AU  - Firth AE
LA  - eng
SI  - GENBANK/JX258842
SI  - GENBANK/JX258843
GR  - WT_/Wellcome Trust/United Kingdom
GR  - 088789/WT_/Wellcome Trust/United Kingdom
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20121004
PL  - United States
TA  - Proc Natl Acad Sci U S A
JT  - Proceedings of the National Academy of Sciences of the United States of America
JID - 7505876
RN  - 0 (Codon)
RN  - 0 (Viral Proteins)
SB  - IM
MH  - Amino Acid Sequence
MH  - Animals
MH  - Arterivirus/*metabolism
MH  - Base Sequence
MH  - Cell Compartmentation
MH  - Codon
MH  - *Frameshift Mutation
MH  - Mammals
MH  - Mass Spectrometry
MH  - Molecular Sequence Data
MH  - Mutagenesis
MH  - Open Reading Frames
MH  - Ribosomes/*metabolism
MH  - Sequence Homology, Nucleic Acid
MH  - Viral Proteins/*biosynthesis/genetics
PMC - PMC3491471
COIS- Conflict of interest statement: The authors have filed a provisional patent 
      application that relates to some aspects of this work.
EDAT- 2012/10/09 06:00
MHDA- 2013/01/08 06:00
PMCR- 2012/10/04
CRDT- 2012/10/09 06:00
PHST- 2012/10/09 06:00 [entrez]
PHST- 2012/10/09 06:00 [pubmed]
PHST- 2013/01/08 06:00 [medline]
PHST- 2012/10/04 00:00 [pmc-release]
AID - 1211145109 [pii]
AID - 201211145 [pii]
AID - 10.1073/pnas.1211145109 [doi]
PST - ppublish
SO  - Proc Natl Acad Sci U S A. 2012 Oct 23;109(43):E2920-8. doi: 
      10.1073/pnas.1211145109. Epub 2012 Oct 4.