Linked Life Data

2728344

Source:http://linkedlifedata.com/resource/pubmed/id/2728344

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1989-7-12
pubmed:databankReference
pubmed:abstractText
SVLM21 is a mutant of Sindbis virus, which in contrast to SVSTD, is able to replicate in Aedes albopictus mosquito cells deprived of methionine. We have obtained evidence that the basis of this low methionine-resistance (LMR) phenotype is the generation of an altered RNA methyltransferase with an increased affinity for S-adenosylmethionine (ado met). We now report that following the substitution of the nucleotide sequence, 126-504, from SVLM21 cDNA for the corresponding sequence of the Toto 1101 plasmid (infectious Sindbis viral RNA can be transcribed from this plasmid) we were able to generate recombinant Sindbis virus (SVMS-65a) with the LMR phenotype. (SVTOTO virus derived from Toto 1101, like SVSTD, lacks the LMR phenotype.) As was the case with SVLM21, SVMS-65a not only possessed the LMR phenotype but also showed an increased sensitivity to Neplanocin A, a potent inhibitor of S-adenosylhomocysteine (ado hcy) hydrolase. Sequencing of the nucleotide 126-504 region from SVLM21 revealed two mutations; these mutations occurred in adjacent codons and lead to two predicted amino acid changes in the SV nsPl protein; at residue 87, from Arg to Leu, and at residue 88 from Ser to Cys. Since the nucleotide sequence 126-504 lies entirely within the gene for nsP1, we conclude that the RNA methyltransferase activity generated by SV is associated with nsP1. We suggest that residues 87 and 88 in nsP1, where the amino acid changes in SVLM21 nsP1 have occurred, are at or near the binding site for ado met; we also suggest that these changes in nsP1 are responsible for the increased affinity of the SVLM21 RNA methyltransferase for ado met and thereby for the LMR phenotype. Alternatively, it is possible that the binding site for ado met is elsewhere on nsP1 or even on another protein, and that the changes at residues 87 and 88 lead to an alteration of the binding site.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0042-6822
pubmed:author
pubmed:issnType
Print
pubmed:volume
170
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
385-91
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Association of the Sindbis virus RNA methyltransferase activity with the nonstructural protein nsP1.
pubmed:affiliation
Department of Molecular Genetics and Microbiology, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Piscataway 08854-5635.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't