Nitrogen and auxin uptake play pivotal roles in seed germination and development.Gastrodia elata,a fully mycoheterotrophic plant,depends entirely on its symbiotic association with Mycena for early growth and seed germ...Nitrogen and auxin uptake play pivotal roles in seed germination and development.Gastrodia elata,a fully mycoheterotrophic plant,depends entirely on its symbiotic association with Mycena for early growth and seed germination.The process by which Mycena supplies nitrogen nutrients and auxin,which are deficient in G.elata,remains poorly understood.In this study,genome-scale analysis of G.elata revealed the loss of genes associated with nitrogen utilization and indole-3-acetic acid(IAA)biosynthesis,which are retained in Mycena.Further analysis of the dynamic transcriptomic interactions between G.elata seeds and Mycena across different symbiotic stages revealed that genes involved in nitrogen-and tryptophan-dependent IAA biosynthesis were significantly upregulated in Mycena during the symbiotic germination of G.elata seeds.Concurrently,G.elata seeds exhibited increased expression of genes involved in the hormone signal trans-duction pathway and the starch and sucrose metabolism pathway.Functional disruption of nitrite reduc-tase(MyNir,EVM0012344)and amidase(MyAmid,EVM0010270),key enzymes in nitrogen assimilation and IAA biosynthesis in Mycena,significantly impaired the symbiotic germination of G.elata seeds.This disruption interfered with energy supply,caused cellular restructuring,and altered hormonal signaling crosstalk.In conclusion,our findings provide novel insights into the mutualistic symbiotic relationship between Mycena and G.elata.Specifically,the fungus Mycena compensates for the incomplete nitrogen metabolism of its plant partner,G.elata,and supplies IAA,thereby promoting seed germination.These re-sults shed light on plant-fungal symbiotic associations from the perspective of nitrogen utilization.展开更多
为了解促天麻(Gastrodia elata)种子萌发真菌的物种多样性,发掘更多促天麻种子萌发真菌资源,笔者对我国亚热带地区广义小菇属(Mycena sensu lato)真菌开展广泛调查和采集,采集324份标本,组织分离获得401个菌株。基于形态特征和ITS、LSU...为了解促天麻(Gastrodia elata)种子萌发真菌的物种多样性,发掘更多促天麻种子萌发真菌资源,笔者对我国亚热带地区广义小菇属(Mycena sensu lato)真菌开展广泛调查和采集,采集324份标本,组织分离获得401个菌株。基于形态特征和ITS、LSU序列的初步分析,选取22个潜在功能菌株与天麻种子开展共萌发研究,结果表明:18个菌株可促进天麻种子萌发,通过进一步形态观察和分子系统发育研究,18个菌株隶属于5属13种,雅典娜小菇属(Atheniella)1种、胶孔菌属(Favolaschia)1种、小菇属(Mycena)8种、扇菇属(Panellus)1种和黏柄小菇属(Roridomyces)2种;13个菌株能促使天麻种子萌发形成天麻原球茎并继续分化,4个菌株使天麻种子的萌发率超过90%。两个沟纹小菇(M. abramsii)菌株和1个红斑小菇(M. maculata)菌株的促天麻种子萌发率均高于目前广泛使用的3个商用黄缘小菇(M. citrinomarginata)菌株(SHXG、MFJ和TMMFJ)。展开更多
Four fungal species of Mycena were identificated from the strains isolated from the protocorm and roots of Orchidaceae species.M anoectochial was isolated from the Proocorm of G.elata, M orchidicola, M.dendrobii and M...Four fungal species of Mycena were identificated from the strains isolated from the protocorm and roots of Orchidaceae species.M anoectochial was isolated from the Proocorm of G.elata, M orchidicola, M.dendrobii and M anoectochila respectively separated from the roots of Cymbidium sinense, Dendrobium candidum and Anoectochilus roxburghii. The symbiotic germination test beteen G. Elata seeds and the above fungal species demonstrated that these flingal species can stimulate the seed germination, Which means the species of Mycena may be the key mycorrhizal fungi of G elata, because there were no reports about the other fungal species Which stimulate G.elata seed germination. Besides G. elata, the above species of Mycena also distributed the roots of the other orchids.展开更多
基金supported by the National Key R&D Program of China(2023YFC3503803)the National Natural Science Foundation of China(32060080)the China Agriculture Research System(CARS-21).
文摘Nitrogen and auxin uptake play pivotal roles in seed germination and development.Gastrodia elata,a fully mycoheterotrophic plant,depends entirely on its symbiotic association with Mycena for early growth and seed germination.The process by which Mycena supplies nitrogen nutrients and auxin,which are deficient in G.elata,remains poorly understood.In this study,genome-scale analysis of G.elata revealed the loss of genes associated with nitrogen utilization and indole-3-acetic acid(IAA)biosynthesis,which are retained in Mycena.Further analysis of the dynamic transcriptomic interactions between G.elata seeds and Mycena across different symbiotic stages revealed that genes involved in nitrogen-and tryptophan-dependent IAA biosynthesis were significantly upregulated in Mycena during the symbiotic germination of G.elata seeds.Concurrently,G.elata seeds exhibited increased expression of genes involved in the hormone signal trans-duction pathway and the starch and sucrose metabolism pathway.Functional disruption of nitrite reduc-tase(MyNir,EVM0012344)and amidase(MyAmid,EVM0010270),key enzymes in nitrogen assimilation and IAA biosynthesis in Mycena,significantly impaired the symbiotic germination of G.elata seeds.This disruption interfered with energy supply,caused cellular restructuring,and altered hormonal signaling crosstalk.In conclusion,our findings provide novel insights into the mutualistic symbiotic relationship between Mycena and G.elata.Specifically,the fungus Mycena compensates for the incomplete nitrogen metabolism of its plant partner,G.elata,and supplies IAA,thereby promoting seed germination.These re-sults shed light on plant-fungal symbiotic associations from the perspective of nitrogen utilization.
文摘Four fungal species of Mycena were identificated from the strains isolated from the protocorm and roots of Orchidaceae species.M anoectochial was isolated from the Proocorm of G.elata, M orchidicola, M.dendrobii and M anoectochila respectively separated from the roots of Cymbidium sinense, Dendrobium candidum and Anoectochilus roxburghii. The symbiotic germination test beteen G. Elata seeds and the above fungal species demonstrated that these flingal species can stimulate the seed germination, Which means the species of Mycena may be the key mycorrhizal fungi of G elata, because there were no reports about the other fungal species Which stimulate G.elata seed germination. Besides G. elata, the above species of Mycena also distributed the roots of the other orchids.
