Orban Axel, Weber Annsophie, Herzog Robert, Hennicke Florian, Rühl Martin
Institute of Food Chemistry and Food Biotechnology, Justus Liebig University Giessen, 35392, Giessen, Hesse, Germany.
International Institute Zittau, Technical University Dresden, 02763, Zittau, Saxony, Germany.
BMC Genomics. 2021 May 4;22(1):324. doi: 10.1186/s12864-021-07648-5.
Cyclocybe aegerita (syn. Agrocybe aegerita) is a commercially cultivated mushroom. Its archetypal agaric morphology and its ability to undergo its whole life cycle under laboratory conditions makes this fungus a well-suited model for studying fruiting body (basidiome, basidiocarp) development. To elucidate the so far barely understood biosynthesis of fungal volatiles, alterations in the transcriptome during different developmental stages of C. aegerita were analyzed and combined with changes in the volatile profile during its different fruiting stages.
A transcriptomic study at seven points in time during fruiting body development of C. aegerita with seven mycelial and five fruiting body stages was conducted. Differential gene expression was observed for genes involved in fungal fruiting body formation showing interesting transcriptional patterns and correlations of these fruiting-related genes with the developmental stages. Combining transcriptome and volatilome data, enzymes putatively involved in the biosynthesis of C8 oxylipins in C. aegerita including lipoxygenases (LOXs), dioxygenases (DOXs), hydroperoxide lyases (HPLs), alcohol dehydrogenases (ADHs) and ene-reductases could be identified. Furthermore, we were able to localize the mycelium as the main source for sesquiterpenes predominant during sporulation in the headspace of C. aegerita cultures. In contrast, changes in the C8 profile detected in late stages of development are probably due to the activity of enzymes located in the fruiting bodies.
In this study, the combination of volatilome and transcriptome data of C. aegerita revealed interesting candidates both for functional genetics-based analysis of fruiting-related genes and for prospective enzyme characterization studies to further elucidate the so far barely understood biosynthesis of fungal C8 oxylipins.
柱状田头菇（同物异名：杨树菇）是一种商业栽培的蘑菇。其典型的伞菌形态以及在实验室条件下完成整个生命周期的能力，使得这种真菌成为研究子实体（担子果、担子体）发育的理想模型。为了阐明迄今为止人们了解甚少的真菌挥发性物质的生物合成过程，我们分析了柱状田头菇不同发育阶段转录组的变化，并将其与不同结实阶段挥发性成分的变化相结合。
我们对柱状田头菇子实体发育的七个时间点进行了转录组学研究，涵盖了七个菌丝体阶段和五个子实体阶段。观察到参与真菌子实体形成的基因存在差异基因表达，呈现出有趣的转录模式，以及这些与结实相关的基因与发育阶段的相关性。结合转录组和挥发物组数据，我们可以鉴定出可能参与柱状田头菇C8氧化脂质生物合成的酶，包括脂氧合酶（LOXs）、双加氧酶（DOXs）、氢过氧化物裂解酶（HPLs）、乙醇脱氢酶（ADHs）和烯还原酶。此外，我们能够确定菌丝体是柱状田头菇培养物顶空中孢子形成过程中占主导地位的倍半萜的主要来源。相比之下，在发育后期检测到的C8成分变化可能归因于子实体中酶的活性。
在本研究中，柱状田头菇挥发物组和转录组数据的结合，为基于功能遗传学分析与结实相关的基因以及进行前瞻性酶表征研究提供了有趣的候选对象，以进一步阐明迄今为止人们了解甚少的真菌C8氧化脂质的生物合成过程。
