Kissing interaction between 3' noncoding and coding sequences is essential for porcine arterivirus RNA replication.
We used an infectious cDNA clone of porcine reproductive and respiratory syndrome virus (PRRSV) to investigate the presence of essential replication elements in the region of the genome encoding the structural proteins. Deletion analysis showed that a stretch of 34 nucleotides (14653 to 14686) within ORF7, which encodes the nucleocapsid protein, is essential for RNA replication. Strand-specific reverse transcription-PCR analysis of viral RNA isolated from transfected BHK-21 cells revealed that this region is required for negative-strand genomic RNA synthesis. The 34-nucleotide stretch is highly conserved among PRRSV isolates and folds into a putative hairpin. A 7-base sequence within the loop of this structure was suggested to base-pair with a sequence present in the loop of a hairpin located in the 3' noncoding region, resulting in a kissing interaction. Mutational analyses confirmed that this kissing interaction is required for RNA replication.
Verheije
M H
MH
Department of Infectious Diseases and Food Chain Quality, Institute for Animal Science and Health, Lelystad, The Netherlands. h.verheije@vet.uu.nl
Olsthoorn
R C L
RC
Kroese
M V
MV
Rottier
P J M
PJ
Meulenberg
J J M
JJ
D020413:3' Untranslated Regions / Q000502:physiology*; D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D009690:Nucleic Acid Conformation; D019251:Nucleocapsid / Q000235:genetics; D016366:Open Reading Frames; D019316:Porcine respiratory and reproductive syndrome virus / Q000235:genetics* / Q000502:physiology; D012367:RNA, Viral / Q000502:physiology*; D013552:Swine; D014763:Viral Matrix Proteins / Q000235:genetics; D017361:Viral Nonstructural Proteins / Q000235:genetics; D014779:Virus Replication / Q000235:genetics*
D020413:3' Untranslated Regions; D012367:RNA, Viral; D014763:Viral Matrix Proteins; D017361:Viral Nonstructural Proteins