Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan;
Biodiversity Research Center, Academia Sinica, Taipei 115, Taiwan.
Proc Natl Acad Sci U S A. 2020 Dec 8;117(49):31267-31277. doi: 10.1073/pnas.2010761117. Epub 2020 Nov 23.
Mushroom-forming fungi in the order Agaricales represent an independent origin of bioluminescence in the tree of life; yet the diversity, evolutionary history, and timing of the origin of fungal luciferases remain elusive. We sequenced the genomes and transcriptomes of five bonnet mushroom species ( spp.), a diverse lineage comprising the majority of bioluminescent fungi. Two species with haploid genome assemblies ∼150 Mb are among the largest in Agaricales, and we found that a variety of repeats between species were differentially mediated by DNA methylation. We show that bioluminescence evolved in the last common ancestor of mycenoid and the marasmioid clade of Agaricales and was maintained through at least 160 million years of evolution. Analyses of synteny across genomes of bioluminescent species resolved how the luciferase cluster was derived by duplication and translocation, frequently rearranged and lost in most species, but conserved in the lineage. Luciferase cluster members were coexpressed across developmental stages, with the highest expression in fruiting body caps and stipes, suggesting fruiting-related adaptive functions. Our results contribute to understanding a de novo origin of bioluminescence and the corresponding gene cluster in a diverse group of enigmatic fungal species.
担子菌类伞菌目真菌代表了生命之树中生物发光的独立起源;然而,真菌荧光素酶的多样性、进化历史和起源时间仍然难以捉摸。我们对五种蕈类物种( spp.)的基因组和转录组进行了测序,这些物种是包含大多数生物发光真菌的多样化谱系。两个具有约 150 Mb 单倍体基因组组装的物种是伞菌目中最大的物种之一,我们发现, 物种之间的各种重复序列是由 DNA 甲基化差异介导的。我们表明,生物发光是在 mycenoid 和 Agaricales 的 marasmioid 分支的最后共同祖先中进化而来的,并通过至少 1.6 亿年的进化得以维持。对生物发光物种基因组之间的同线性分析解决了荧光素酶簇如何通过复制和转位衍生的问题,该过程在大多数 物种中经常发生重排和丢失,但在 谱系中得到了保守。荧光素酶簇成员在发育阶段表达共调控,在蕈体盖和菌柄中表达最高,表明与蕈体形成相关的适应性功能。我们的研究结果有助于理解在一个多样化的神秘真菌物种群体中生物发光的从头起源和相应的基因簇。