Linking transcriptomic and genomic variation to growth in brook charr hybrids (Salvelinus fontinalis, Mitchill)

Hybridization can lead to phenotypic differences arising from changes in gene expression patterns or new allele combinations. Variation in gene expression is thought to be controlled by differences in transcription regulation of parental alleles, either through cis or trans regulatory elements. A previous study among brook charr hybrids from different populations (Rupert, Laval, and domestic) showing distinct length at age during early life stages also revealed different patterns in transcription regulation inheritance of transcript abundance. In the present study, transcript abundance by means of RNA-seq and qRT-PCR, SNP genotypes and allelic imbalance were assessed in order to understand the molecular mechanisms underlying the observed transcriptomic and differences in length at age among domestic × Rupert hybrids and Laval × domestic hybrids. We found 198 differentially expressed genes between the two hybrid crosses and allelic imbalance could be analyzed for 69 of them. Among these ...杂交可通过基因表达模式的改变或新等位基因组合的形成，引发表型差异。目前认为，基因表达的变异受亲本等位基因转录调控差异的控制，调控途径包括顺式（cis）、反式（trans）调控元件。此前一项针对不同群体（鲁珀特（Rupert）种群、拉瓦尔（Laval）种群及养殖群体）溪红点鲑杂交后代的研究显示，其早期生活阶段的体长存在显著差异，同时还揭示了转录本丰度的转录调控遗传模式存在差异。本研究通过RNA测序（RNA-seq）与实时定量荧光PCR（qRT-PCR）技术，对转录本丰度、单核苷酸多态性（SNP）基因型及等位基因失衡情况进行了检测，以期阐明养殖×鲁珀特杂交后代与拉瓦尔×养殖杂交后代中，所观测到的转录组差异与体长差异背后的分子机制。本研究在两组杂交组合间共鉴定出198个差异表达基因，其中69个可用于等位基因失衡分析。在上述……