The transcriptional consequences of mutation and natural selection in Caenorhabditis elegans

This set of arrays contains all microarray experiments done involving comparisons among C. elegans natural isolates and mutation-accumulation lines. Abstract: The evolutionary importance of gene-expression divergence is unclear: some studies suggest that it is an important mechanism for evolution by natural selection, whereas others claim that most between-species regulatory changes are neutral or nearly neutral. We examined global transcriptional divergence patterns in a set of Caenorhabditis elegans mutation-accumulation lines and natural isolate lines to provide insights into the evolutionary importance of transcriptional variation and to discriminate between the forces of mutation and natural selection in shaping the evolution of gene expression. We detected the effects of selection on transcriptional divergence patterns and characterized them with respect to coexpressed gene sets, chromosomal clustering of expression changes and functional gene categories. We directly compared observed transcriptional variation patterns in the mutation-accumulation and natural isolate lines to a neutral model of transcriptome evolution to show that strong stabilizing selection dominates the evolution of transcriptional change for thousands of C. elegans expressed sequences. An all pairs experiment design type is where all labeled extracts are compared to every other labeled extract. Keywords: all_pairs本阵列数据集涵盖了所有针对秀丽隐杆线虫（Caenorhabditis elegans，简称C. elegans）自然分离株（natural isolates）与突变积累系（mutation-accumulation lines）之间比较的基因微阵列（microarray）实验。 摘要：基因表达分化的进化重要性尚无定论：部分研究认为其是自然选择驱动演化的关键机制，而另有研究则提出，物种间多数调控变化属于中性或近中性演化。本研究通过分析一组秀丽隐杆线虫突变积累系与自然分离株的全局转录分化模式，旨在阐明转录变异的进化重要性，并区分突变压力与自然选择在塑造基因表达演化过程中的作用。本研究检测了自然选择对转录分化模式的影响，并从共表达基因集、表达变化的染色体聚类以及功能基因类别三个维度对其进行了表征。随后，本研究将突变积累系与自然分离株中观测到的转录变异模式与转录组演化的中性模型进行直接比对，结果显示，数千个秀丽隐杆线虫表达序列的转录变化演化主要受强烈的稳定选择（stabilizing selection）主导。 全配对实验设计（all pairs experiment design）指将所有标记提取物两两进行比较的实验设计类型。 关键词：all_pairs