Changes in gene regulation underlie much of phenotypic evolution 1 . However, our understanding of the potential for regulatory evolution is biased, because most evidence comes from either natural variation or limited experimental perturbations 2 . Using an automated robotics pipeline, we surveyed an unbiased mutation library for a developmental enhancer in Drosophila melanogaster . We found that almost all mutations altered gene expression and that parameters of gene expression—levels, location, and state—were convolved. The widespread pleiotropic effects of most mutations may constrain the evolvability of developmental enhancers. Consistent with these observations, comparisons of diverse Drosophila larvae revealed apparent biases in the phenotypes influenced by the enhancer. Developmental enhancers may encode a higher density of regulatory information than has been appreciated previously, imposing constraints on regulatory evolution. A robotic pipeline is used to survey a library of mutations in a Drosphila gene enhancer, showing that most mutations altered gene expression and had widespread pleiotropic effects that are likely to constrain regulatory evolution.

中文翻译：

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发育增强剂中的密集和多效性调控信息

基因调控的变化是大部分表型进化的基础 1。然而，我们对监管演变潜力的理解是有偏见的，因为大多数证据来自自然变异或有限的实验扰动 2。使用自动化机器人管道，我们调查了黑腹果蝇发育增强剂的无偏突变库。我们发现几乎所有的突变都会改变基因表达，并且基因表达的参数——水平、位置和状态——都是经过卷积的。大多数突变的广泛多效性效应可能会限制发育增强子的进化能力。与这些观察结果一致，不同果蝇幼虫的比较揭示了受增强子影响的表型的明显偏差。发育增强子可以编码比以前认识的更高密度的调节信息，从而对调节进化施加限制。机器人管道用于调查果蝇基因增强子中的突变库，表明大多数突变改变了基因表达并具有广泛的多效性效应，可能会限制调节进化。