Linked Life Data

6940129

Source:http://linkedlifedata.com/resource/pubmed/id/6940129

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1981-7-9
pubmed:abstractText
Nucleotide substitutions within a structural gene can cause two principal "drastic" phenotypic effects at the protein level: translatable leads to untranslatable and nonpolar hydrophobic in equilibrium hydrophilic amino acid substitutions. The sequence of nucleotides in the structural human alpha- and beta-globin genes and their variants were examined to determine whether codon usage, patterns of nucleotide substitutions, or both, reduced the relative and absolute rates of these unfavorable mutations. Based on translation of abnormal hemoglobins, it is likely that all 61 nontermination codons are potentially translatable, though only 47 are normally used. Moreover, codons that can mutate to a termination codon are never used whenever the corresponding amino acid is specified also by triplets that cannot mutate to termination by a single-step mutation. Thus, the number of opportunities to mutate to an untranslatable codon is reduced to the minimum compatible with the amino acid composition of these chains. The relative rates of U in equilibrium non-U substitutions were much lower than those of other substitutions. Because U residues must be involved in most termination mutations and in all nonpolar hydrophobic in equilibrium hydrophilic amino acid substitutions, there is a considerable reduction of mutational events, causing drastic phenotypic effects. These findings are likely to be the end result of evolutionary selection by yet unknown mechanisms.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0027-8424
pubmed:author
pubmed:issnType
Print
pubmed:volume
78
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1110-4
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1981
pubmed:articleTitle
Nonrandom patterns of codon usage and of nucleotide substitutions in human alpha- and beta-globin genes: an evolutionary strategy reducing the rate of mutations with drastic effects?
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.