Linked Life Data

9032340

Source:http://linkedlifedata.com/resource/pubmed/id/9032340

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-3-18
pubmed:abstractText
Proteolytic processing of the Rous sarcoma virus (RSV) Gag precursor was altered in vivo through the introduction of amino acid substitutions into either the polyprotein cleavage junctions or the PR coding sequence. Single amino acid substitutions (V(P2)S and P(P4)G), which are predicted from in vitro peptide substrate cleavage data to decrease the rate of release of PR from the Gag polyprotein, were placed in the NC portion of the NC-PR junction. These substitutions do not affect the efficiency of release of virus-like particles from COS cells even though recovered particles contain significant amounts of uncleaved Pr76gag in addition to mature viral proteins. Single amino acid substitutions (A(P3)F and S(P1)Y), which increase the rate of PR release from Gag, also do not affect budding of virus-like particles from cells. Substitution of the inefficiently cleaved MA-p2 junction sequence in Gag by eight amino acids from the rapidly cleaved NC-PR sequence resulted in a significant increase in cleavage at the new MA-p2 junction, but again without an effect on budding. However, decreased budding was observed when the A(P3)F or S(P1)Y substitution was included in the NC-PR junction sequence between the MA and p2 proteins. A budding defect was also caused by substitution into Gag of a PR subunit containing three amino acid substitutions (R105P, G106V, and S107N) in the substrate binding pocket that increase the catalytic activity of PR. The defect appears to be the result of premature proteolytic processing that could be rescued by inactivating PR through substitution of a serine for the catalytic aspartic acid residue. This budding defect was also rescued by single amino acid substitutions in the NC-PR cleavage site which decrease the rate of release of PR from Gag. A similar budding defect was caused by replacing the Gag PR with two PR subunits covalently linked by four glycine residues. In contrast to the defect caused by the triply substituted PR, the budding defect observed with the linked PR dimer could not be rescued by NC-PR cleavage site mutations, suggesting that PR dimerization is a limiting step in the maturation process. Overall, these results are consistent with a model in which viral protein maturation occurs after PR subunits are released from the Gag polyprotein.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-1310781, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-1315755, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-1331099, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-1540403, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-1656090, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-1697912, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-1710290, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-1848230, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-1874717, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-1883539, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-195394, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-2014242, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-2162350, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-2405382, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-2537209, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-2550669, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-3290901, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-3882995, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-7526778, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-7666544, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-7666550, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-7745738, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-7816094, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8083996, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8157644, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8254734, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8352596, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8389361, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8394460, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8411352, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8530341, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8631853, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8648711, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8661444, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8764091, http://linkedlifedata.com/resource/pubmed/commentcorrection/9032340-8850005
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-538X
pubmed:author
pubmed:issnType
Print
pubmed:volume
71
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2083-91
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Altered Rous sarcoma virus Gag polyprotein processing and its effects on particle formation.
pubmed:affiliation
Department of Biochemistry, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't