Henke Catarina, Jung Elke-Martina, Voit Annekatrin, Kothe Erika, Krause Katrin
Institute of Microbiology, Friedrich Schiller University Jena, Microbial Communication, Jena, Germany.
J Basic Microbiol. 2016 Feb;56(2):162-74. doi: 10.1002/jobm.201500381. Epub 2015 Sep 7.
Ectomycorrhizal symbiosis is important for forest ecosystem functioning with tree-fungal cooperation increasing performance and countering stress conditions. Aldehyde dehydrogenases (ALDHs) are key enzymes for detoxification and thus may play a role in stress response of the symbiotic association. With this focus, eight dehydrogenases, Ald1 through Ald7 and TyrA, of the ectomycorrhizal basidiomycete Tricholoma vaccinum were characterized and phylogenetically investigated. Functional analysis was performed through differential expression analysis by feeding different, environmentally important substances. A strong effect of indole-3-acetic acid (IAA) was identified, linking mycorrhiza formation and auxin signaling between the symbiosis partners. We investigated ald1 overexpressing strains for performance in mycorrhiza with the host tree spruce (Picea abies) and observed an increased width of the apoplast, accommodating the Hartig' net hyphae of the T. vaccinum over-expressing transformants. The results support a role for Ald1 in ectomycorrhiza formation and underline functional differentiation within fungal aldehyde dehydrogenases in the family 1 of ALDHs.
外生菌根共生对于森林生态系统功能至关重要，树木与真菌的合作可提高性能并应对胁迫条件。醛脱氢酶（ALDHs）是解毒的关键酶，因此可能在共生体的应激反应中发挥作用。基于此，对外生菌根担子菌牛肝菌的8种脱氢酶（Ald1至Ald7和TyrA）进行了表征和系统发育研究。通过添加不同的、对环境重要的物质进行差异表达分析来进行功能分析。研究发现吲哚-3-乙酸（IAA）具有很强的作用，将菌根形成与共生伙伴之间的生长素信号联系起来。我们研究了过表达ald1的菌株与宿主树云杉（Picea abies）形成菌根的性能，观察到质外体宽度增加，容纳了过表达转化体的牛肝菌哈蒂氏网菌丝。结果支持Ald1在菌根形成中的作用，并强调了ALDHs家族1中真菌醛脱氢酶的功能分化。
