Linked Life Data

9402741

Source:http://linkedlifedata.com/resource/pubmed/id/9402741

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1998-1-15
pubmed:abstractText
Retrosequences, genes, and pseudogenes originated by retrotranscription are frequent components of vertebrate genomes, but they have only occasionally been described in invertebrates. In Drosophila, very few retrosequences have been reported, among them those of alcohol dehydrogenase (Adh) and phosphoglyceromutase (Pglym). Although 52 Adh gene sequences are available for comparison, Adh retrosequences have been described only in the sibling species D. teissieri and D. yakuba (melanogaster subgroup) and in D. subobscura (obscura subgroup). Here, we report the presence of Adh retrosequences in two closely related species of D. subobscura: D. madeirensis and D. guanche. Extensive sequence comparisons with their functional paralogs suggest separate retrotranscriptional events: one in the melanogaster subgroup in the ancestor of D. teissieri and D. yakuba, and the other in the obscura subgroup before the radiation of the lineages leading to D. subobscura, D. madeirensis, and D. guanche. In the former, the Adh retrotranscript originated a new expressed gene, named jingwei. However, in the obscura Adh retrosequences, retention of codon bias and higher Ks than Ka values, both distinctive evolutionary features supporting functionality, have to be considered together with a frameshift, premature stop codons, and other nucleotide substitutions, which, added to the lack of the original promoter elements, suggest that they are pseudogenes. At least two different Adh retrosequences have been characterized in each of the obscura species, and their phylogenetic analysis indicates that paralogs and their flanking genomic regions share a higher degree of similarity than orthologous sequences. Two alternative hypotheses could explain this current organization and structure: either a multiplication event occurred independently in each species, or gene conversion events should be invoked after a single duplication in the species ancestor. The significance of retrotranscriptional events in the evolution of invertebrate genomes is discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0737-4038
pubmed:author
pubmed:issnType
Print
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1316-25
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Characterization and molecular analysis of Adh retrosequences in species of the Drosophila obscura group.
pubmed:affiliation
Department de Genètica, Facultat de Biologia, Universitat de Barcelona, Spain.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't