Abstract：
High-elevation adaptation provides an excellent system for examining adaptive evolution, and adaptive variations may manifest at gene expression or any other phenotypic levels. We examined gene expression profiles of Asiatic toads (Bufo gargarizans) along an elevational gradient from both wild and common-garden acclimated populations. Asiatic toads originated from high altitudes have distinctive gene expression patterns. We identified 18 fixed differentially expressed genes (DEGs), which are different in both wild and acclimated samples, and 1217 plastic DEGs, which are different among wild samples. The expression levels of most genes were linearly correlated with altitude gradient and down-regulated in high-altitude populations. Expression variations of several genes associated with metabolic process are fixed, and we also identified a co-expression module that is significantly different between acclimated populations and has functions related to DNA repair. The differential expression of the vast majority genes, however, are due to phenotypic plasticity, revealing the highly plastic nature of gene expression variations. Expression modification of some specific genes related to metabolism and response to UV radiation play crucial role in adaptation to high altitude for Asiatic toads. Common-garden experiments are essential for evaluating adaptive evolution of natural populations.
摘要：
高海拔适应为检查自适应进化提供了一个极好的系统，和适应性变异可能表现在基因表达或任何其他表型水平。我们检查了野生和普通花园适应种群沿海拔梯度的亚洲蟾蜍（Bufogargarizans）的基因表达谱。起源于高海拔地区的亚洲蟾蜍具有独特的基因表达模式。我们确定了18个固定的差异表达基因（DEGs），在野生和适应的样本中都不同，和1217个塑料DEG，在野生样本中是不同的。大多数基因的表达水平与海拔梯度呈线性相关，并在高海拔人群中下调。与代谢过程相关的几个基因的表达变异是固定的，我们还确定了一个共表达模块，该模块在适应种群之间存在显着差异，并且具有与DNA修复相关的功能。绝大多数基因的差异表达，然而,是由于表型可塑性，揭示了基因表达变异的高度可塑性。一些与代谢和对紫外线辐射响应相关的特定基因的表达修饰在亚洲蟾蜍适应高海拔地区中起着至关重要的作用。普通花园实验对于评估自然种群的适应性进化至关重要。
