Linked Life Data

8683216

Source:http://linkedlifedata.com/resource/pubmed/id/8683216

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1996-8-16
pubmed:databankReference
pubmed:abstractText
The nucleotide sequence of a 3266 bp region encompassing open reading frames (ORFs) 2 through 7 of the porcine reproductive and respiratory syndrome virus (PRRSV) was determined for 10 isolates recovered from the midwestern United States. Pairwise comparisons showed that genetic distances between isolates ranged from 2.5% to 7.9% (mean 5.8% +/- 0.2%) whereas the Lelystad strain from Europe was, on average, 34.8% divergent from US clones. Thus, US and European PRRSV isolates represent genetically distinct clusters of the same virus. ORF 5, which encodes the envelope glycoprotein, was the most polymorphic [total nucleotide diversity (pi) = 0.097 +/- 0.007] and ORF 6, encoding the viral M protein, was the most conserved (pi = 0.038 +/- 0.003). The substantial differences in nucleotide diversity among ORFs suggests that the virus is evolving by processes other than simple accumulation of random neutral mutations. In support of this hypothesis, statistical analyses of the nucleotide sequence provided strong evidence for intragenic recombination or gene conversion in ORFs 2, 3, 4, 5 and 7, but not in ORF 6. An excess of synonymous (silent) substitutions was observed in all six ORFs, indicating an evolutionary pressure to conserve amino acid sequences. Taken together, the data indicate that despite intragenic recombination among extant PRRSV isolates, purifying selection has acted to maintain the primary structure of individual ORFs.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-1317
pubmed:author
pubmed:issnType
Print
pubmed:volume
77 ( Pt 6)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1271-6
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Genetic variation in porcine reproductive and respiratory syndrome virus isolates in the midwestern United States.
pubmed:affiliation
Department of Veterinary PathoBiology, University of Minnesota, St Paul 55108, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't