干旱胁迫下藜麦种子糖代谢转录组学研究

Transcriptomics of Glucose Metabolism in Quinoa Seeds under Drought Stress Treatment

藜麦(Chenopodium quinoa Willd.)营养丰富且抗逆性较强。本研究以M059(胚根生长快)和M024(胚根生长慢)两种藜麦种质材料为研究对象,采用PEG-6000模拟干旱胁迫,观察种子表型的解剖结构,对发芽种子进行糖含量测定,并对正常水处理和干旱处理的材料进行转录组测序。种子表型及糖含量测定结果显示:与正常水处理相比,15%PEG-6000处理24 h后M059和M024胚根长度分别降低68.65%和71.43%;在正常水处理条件下,M059的可溶性总糖、蔗糖、葡萄糖和果糖含量较M024高18.58%、97.84%、70.54%和32.77%;在15%PEG-6000处理24 h后,M024的蔗糖含量比M059高23.01%,M059的可溶性总糖和葡萄糖含量比M024分别高7.26%和25.00%。韦恩图分析结果表明,C1vsD1、C2vsD2、C1vsC2和D1vsD2比较组中共有差异表达基因211个,特异性差异表达基因分别为132个、1270个、578个和914个。GO富集分析表明,与干旱胁迫下藜麦种子糖代谢的分子响应密切相关的GO通路有5条。KEGG富集分析表明,与干旱胁迫下藜麦种子糖代谢密切相关的代谢途径有3条。根据差异表达基因的功能注释,有10个差异表达基因(LOC110702784_AGAL2、LOC110719866_INV1、LOC110717843_TPPJ、LOC29490_CELB、LOC110719843_bg1x、LOC110689796_SUS1、LOC110690728_MAN6、LOC110729879_HK2、LOC110712726_EGLC、LOC110734349_FK7)与糖代谢相关,且这10个差异表达基因的qRT-PCR验证结果与转录组结果一致。本研究结果将对深入解析藜麦响应干旱的分子调控机制提供参考。

Quinoa(Chenopodium quinoa Willd.)has rich nutritional and strong stress resistance.In this study,two kinds of quinoa germplasm materials,M059(fast radicule growth)and M024(slow radicule growth),were used to simulate drought stress with PEG-6000.The anatomical structure of seed phenotypes was observed,glucose contents were determined in germinated seeds,and transcripome sequencing was performed on materials treated with normal water and drought.The results of seed phenotype and glucose contents determination showed that the radicles length of M059 and M024 decreased by 68.65%and 71.43%,respectively,after 15%PEG-6000 treatment for 24 h compared with normal water treatment.Under normal water treatment conditions,the contents of total soluble sugar,sucrose,glucose and fructose in M059 were 18.58%,97.84%,70.54%and 32.77%higher than those in M024.After being treated with 15%PEG-6000 for 24 h,the sucrose content of M024 was 23.01%higher than that of M059,and the soluble total sugar and glucose content of M059 were 7.26%and 25.00%higher than that of M024,respectively.Venn diagram analysis showed that there were 211 differentially expressed genes in C1vsD1,C2vsD2,C1vsC2 and D1vsD2 comparison groups,and 132,1270,578 and 914 differentially expressed genes,respectively.GO and KEGG enrichment analyses showed that 5 GO terms and 3 metabolic pathways were closely related to the molecular response of glucose metabolism in quinoa seeds under drought stress.Based on functional annotations of differentially expressed genes,there were 10 differentially expressed genes(LOC110702784_AGAL2,LOC110719866_INV1,LOC110717843_TPPJ,LOC29490_CELB,LOC110719843_bg1x,LOC110689796_SUS1,LOC110690728_MAN6,LOC110729879_HK2,LOC110712726_EGLC,LOC110734349_FK7)were related to glucose metabolism,and the qRT-PCR verification results of these 10 differentially expressed genes were consistent with the transcriptomic results.The results of this study will provide reference for further analysis of the molecular regulatory mechanism under drought stress in quinoa.