Hwang Jonathan, Zhao Qi, Yang Zhu L, Wang Zheng, Townsend Jeffrey P
Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect Street, New Haven, CT 06520, USA.
Key Laboratory for Plant Biodiversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China.
Environ Microbiol Rep. 2015 Aug;7(4):658-67. doi: 10.1111/1758-2229.12303. Epub 2015 Jul 1.
The relation between ecological and genetic divergence of Helvella species (saddle fungi) has been perplexing. While a few species have been clearly demonstrated to be ectomycorrhizal fungi, ecological roles of many other species have been controversial, alternately considered as either saprotrophic or mycorrhizal. We applied SATé to build an inclusive deoxyribonucleic acid sequence alignment for the internal transcribed spacers (ITS) of annotated Helvella species and related environmental sequences. Phylogenetic informativeness of ITS and its regions were assessed using PhyDesign. Mycorrhizal lineages present a diversity of ecology, host type and geographic distribution. In two Helvella clades, no Helvella ITS sequences were recovered from root tips. Inclusion of environmental sequences in the ITS phylogeny from these sequences has the potential to link these data and reveal Helvella ecology. This study can serve as a model for revealing the diversity of relationships between unculturable fungi and their potential plant hosts. How non-mycorrhizal life styles within Helvella evolved will require expanded metagenomic investigation of soil and other environmental samples along with study of Helvella genomes.
皱盖钟菌属（马鞍菌）物种的生态与遗传分化之间的关系一直令人困惑。虽然少数物种已被明确证明是外生菌根真菌，但许多其他物种的生态作用一直存在争议，有人认为它们是腐生菌，也有人认为它们是菌根菌。我们应用SATé为已注释的皱盖钟菌属物种的内部转录间隔区（ITS）构建了一个全面的脱氧核糖核酸序列比对，并纳入了相关的环境序列。使用PhyDesign评估了ITS及其区域的系统发育信息性。菌根谱系呈现出生态、宿主类型和地理分布的多样性。在两个皱盖钟菌进化枝中，未从根尖中获得皱盖钟菌的ITS序列。将这些环境序列纳入ITS系统发育中，有可能将这些数据联系起来并揭示皱盖钟菌的生态。这项研究可以作为一个模型，用于揭示不可培养真菌与其潜在植物宿主之间关系的多样性。皱盖钟菌属内非菌根生活方式是如何进化的，这需要对土壤和其他环境样本进行更广泛的宏基因组研究，并结合皱盖钟菌基因组的研究。
