Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1975-4-21
pubmed:abstractText
Three ochre and two amber mutants in yeast have been definitively identified by the amino acid replacements in iso-1-cytochromes c from intragenic revertants. Except for rare and sometimes unusual changes, all of the replacements were single amino acids whose codons differed from UAA or UAG by one base. These assignments, which were based on the absence of tryptophan replacements in ochre revertants, could be corroborated from the studies of two groups of suppressors that were shown to act on either the ochre or amber mutants. All five nonsense mutants are located at different sites in the cyc1 gene and all are at sites that can be occupied by amino acids having a wide range of structures. The relative frequencies of the amino acid replacements indicate that identical codons located at different sites may respond differently to a mutagenic agent. Notably glutamine replacements occurred almost exclusively in UV-induced revertants of only one ochre mutant cyc1-9, but not at all or at reduced proportions in the others. Similarly, lysine replacements occurred almost exclusively in the NA-induced revertants of only the ochre mutant cyc1-72, but not at all in the others. These and other results reveal that mutation of A.T base pairs by UV and nitrous acid are dependent upon the location of the codon within the gene as well as the location of the base pair within the codon. From these findings, it appears as if the type of base-pair changes induced by UV and nitrous acid are strongly influenced by adjacent nucleotide sequences.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-13688038, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-16590840, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-4178406, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-4367877, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-4554815, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-4603163, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-5050363, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-5227668, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-5320272, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-5516346, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-5685784, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-5771953, http://linkedlifedata.com/resource/pubmed/commentcorrection/4374411-6061656
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0016-6731
pubmed:author
pubmed:issnType
Print
pubmed:volume
78
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
97-113
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1974
pubmed:articleTitle
Variation of mutagenic action on nonsense mutants at different sites in the iso-1-cytochrome c gene of yeast.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.