ABSTRACT: Sequencing a normalized cDNA library to study the effect of natural selection on sequence evolution in the brook charr, Salvelinus fontinalis
Project description:Domestication has been practiced for centuries yet directed towards relatively few terrestrial crops and animals. While phenotypic and quantitative genetic changes associated with domestication have been amply documented, little is known about the molecular changes underlying the phenotypic evolution during the process. Here, we have investigated the brook charr (Salvelinus fontinalis) responses to artificial selection by means of transcriptional analysis of ~ 32 000 cDNA features performed in both a selected and control populations reared under identical environmental conditions during four generations. Our results indicate that selective breeding led to significant changes in the transcription of genes at the juvenile stage, where we observed 4.16% (156/3750) of differentially expressed genes between the two lines. No significant genes were revealed at the earlier life stage. Moreover, when comparing our results to those of previous studies on Atlantic salmon that compared lines that were selected for 5-7 generations for similar traits (e.g. growth), genes with similar biological functions were found to be under selection in both studies. These observations indicate that (1) four generations of selection caused substantial changes in regulation of gene transcription between selected and control populations and (2) selective breeding for improving the same phenotypic traits (e.g. rapid growth) in brook charr and Atlantic salmon tended to select for the same changes in transcription profiles as the expression of a small and similar set of genes were affected by selection.
Project description:Salvelinus Microarray experiment: The influence of parental effects on transcriptomic landscape during early development in brook charr (Salvelinus fontinalis, Mitchill)
Project description:Domestication has been practiced for centuries yet directed towards relatively few terrestrial crops and animals. While phenotypic and quantitative genetic changes associated with domestication have been amply documented, little is known about the molecular changes underlying the phenotypic evolution during the process. Here, we have investigated the brook charr (Salvelinus fontinalis) responses to artificial selection by means of transcriptional analysis of ~ 32 000 cDNA features performed in both a selected and control populations reared under identical environmental conditions during four generations. Our results indicate that selective breeding led to significant changes in the transcription of genes at the juvenile stage, where we observed 4.16% (156/3750) of differentially expressed genes between the two lines. No significant genes were revealed at the earlier life stage. Moreover, when comparing our results to those of previous studies on Atlantic salmon that compared lines that were selected for 5-7 generations for similar traits (e.g. growth), genes with similar biological functions were found to be under selection in both studies. These observations indicate that (1) four generations of selection caused substantial changes in regulation of gene transcription between selected and control populations and (2) selective breeding for improving the same phenotypic traits (e.g. rapid growth) in brook charr and Atlantic salmon tended to select for the same changes in transcription profiles as the expression of a small and similar set of genes were affected by selection. Two conditions environment: direct comparison of control vs domesticated fish for 20 families. No individual replicates but two individuals of the same family were hybridized on different slides