Transcriptome changes after genome-wide admixture in invasive sculpins (Cottus)
Transcriptome changes after genome-wide admixture in invasive sculpins (Cottus)
复制标题
DOI：
10.1111/j.1365-294x.2012.05645.x
复制
发表时间：
2012-10-01
影响因子：
4.9
通讯作者：
Nolte, Arne W.
中科院分区：
文献类型：
--
作者：
Czypionka, Till;Cheng, Jie;Nolte, Arne W.
杂交物种形成模型假设杂交会产生增加的表型变异，并用于侵入新的适应性峰值。我们测试在何种程度上可以追溯到这种预测使用的基因表达数据在鱼类Cottus perifretum和Cottus cancalanus以及一个自然的混合血统被称为入侵杜父鱼。此外，种间杂交被用来探索从初始阶段到杂交谱系的进化轨迹。对EST（表达序列标签）文库进行测序以设计寡核苷酸微阵列，所述寡核苷酸微阵列针对结合行为中的探针特异性差异进行校准。物种之间的基因表达差异水平与中性标记处的遗传差异相关，因此，入侵性杜父鱼总体上介于亲本物种之间。然而，杂交谱系是通过独特的基因表达模式，丰富的生物功能，代表候选人的健身属性的入侵杜父鱼的区别。我们比较F2杂交与自然入侵杜父鱼，以表明在基因表达的方差降低入侵。此外，在F2杂交中，很少能直接观察到区分入侵者的基因表达的超亲模式。这表明侵入性转录组在混合后发生了继发性变化。这一结果符合进化过程，减少了适应不良的变异，优化了新兴杂交谱系的表型。
Models on hybrid speciation assume that hybridization generates increased phenotypic variance that is utilized to invade new adaptive peaks. We test to what extent this prediction can be traced using gene expression data in the fish species Cottus perifretum and Cottus rhenanus as well as a natural hybrid lineage referred to as invasive sculpins. In addition, interspecies crosses were used to explore evolutionary trajectories from initial stages to the hybrid lineage. EST (expressed sequence tag) libraries were sequenced to design an oligonucleotide microarray that was calibrated for probe-specific differences in binding behaviour. Levels of gene expression divergence between species correlate with genetic divergence at neutral markers and, accordingly, invasive sculpins were intermediate between the parental species overall. However, the hybrid lineage is distinguished through unique patterns of gene expression that are enriched for biological functions which represent candidates for the fitness properties of invasive sculpins. We compare F2 crosses with natural invasive sculpins to show that the variance in gene expression decreases in invasives. Moreover, few of the transgressive patterns of gene expression that distinguish invasives can be directly observed in F2 crosses. This suggests that the invasive transcriptome was subject to secondary changes after admixture. The result is in line with an evolutionary process that reduces maladaptive variance and optimizes the phenotype of an emerging hybrid lineage.