Codon usage bias and tRNA over-expression in Buchnera aphidicola after aromatic amino acid nutritional stress on its host Acyrthosiphon pisum.
Nucleic Acids Res
; 34(16): 4583-92, 2006.
Article
em En
| MEDLINE
| ID: mdl-16963497
ABSTRACT
Codon usage bias and relative abundances of tRNA isoacceptors were analysed in the obligate intracellular symbiotic bacterium, Buchnera aphidicola from the aphid Acyrthosiphon pisum, using a dedicated 35mer oligonucleotide microarray. Buchnera is archetypal of organisms living with minimal metabolic requirements and presents a reduced genome with high-evolutionary rate. Codonusage in Buchnera has been overcome by the high mutational bias towards AT bases. However, several lines of evidence for codon usage selection are given here. A significant correlation was found between tRNA relative abundances and codon composition of Buchnera genes. A significant codon usage bias was found for the choice of rare codons in Buchnera C-ending codons are preferred in highly expressed genes, whereas G-ending codons are avoided. This bias is not explained by GC skew in the bacteria and might correspond to a selection for perfect matching between codon-anticodon pairs for some essential amino acids in Buchnera proteins. Nutritional stress applied to the aphid host induced a significant overexpression of most of the tRNA isoacceptors in bacteria. Although, molecular regulation of the tRNA operons in Buchnera was not investigated, a correlation between relative expression levels and organization in transcription unit was found in the genome of Buchnera.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Afídeos
/
Códon
/
RNA de Transferência
/
Regulação Bacteriana da Expressão Gênica
/
Buchnera
Limite:
Animals
Idioma:
En
Revista:
Nucleic Acids Res
Ano de publicação:
2006
Tipo de documento:
Article
País de afiliação:
França