转录组和代谢组分析瘤菌根菌对铁皮石斛的促生机制

Transcriptome Sequencing and Metabolite Analysis for Revealing the Growth Promoting Mechanism of Epulorhiza sp. of Dendrobium officinale

摘要:

为筛选出促进铁皮石斛(Dendrobium officinale)生长的差异表达基因和差异代谢物，对瘤菌根菌与无菌盆栽铁皮石斛苗共生后形成的侧根根系进行转录组、代谢组和双组学联合分析。结果表明，转录组分析共找到262条差异表达基因富集到了35条通路中，其中内质网蛋白质加工通路途径的差异基因最多，其次为氨基糖和核苷酸糖代谢通路。代谢组分析共检测出194个差异代谢物富集到33个KEGG通路中，其中代谢途径的差异代谢物最多有133个，其次为不同环境的微生物代谢途径的差异代谢物有70个。通过联合分析，有9个差异基因的差异表达导致丝氨酸、谷氨酸、d-甘露糖和激素等代谢物的积累量发生变化，这可能是瘤菌根菌促进铁皮石斛生长的重要原因。因此，推测瘤菌根菌促进铁皮石斛生长与氨基酸、糖、植物激素的积累及相关基因的表达变化有关。

Abstract:

To screen the differentially expressed genes (DEGs) and differential metabolites (DMs) that promote the growth of Dendrobium officinale, transcriptomic, metabolomic and biomic analysis were performed on the lateral roots formed after the symbiosis of tumorrhizal bacteria and sterile potted D. officinale seedlings. The result showed that a total of 262 DEGs were found and enriched into 35 pathways by transcriptome analysis, among which endoplasmic reticulum protein processing pathway had the most DEGs, followed by amino sugar and nucleotide sugar metabolism pathways. A total of 194 DMs were detected enriched in 33 KEGG pathways by metabolomic analysis, among which 133 DMs were in metabolic pathways, followed by 70 DMs in microbial metabolic pathways of different environments. Combined analysis showed that the differential expression of 9 DEGs resulted in changes in the accumulation of metabolites, such as serine, glutamate, d-mannose and hormones, which might be an important reason for Epulorhiza sp. to promote the growth of D. officinale. Therefore, it was suggested that the growth of D. officinale promoted by Epulorhiza sp. was related to the accumulation of amino acids, sugars, phytohormones and the expression changes of related genes.