Linfeng Xie, Yan Guo, Chuanhong Ren, Yunlin Cao, Jiajia Li, Jing Lin, Donald Grierson, Xiaoyong Zhao, Bo Zhang, Chongde Sun, Kunsong Chen, Xian Li
{"title":"Unravelling the consecutive glycosylation and methylation of flavonols in peach in response to UV-B irradiation","authors":"Linfeng Xie, Yan Guo, Chuanhong Ren, Yunlin Cao, Jiajia Li, Jing Lin, Donald Grierson, Xiaoyong Zhao, Bo Zhang, Chongde Sun, Kunsong Chen, Xian Li","doi":"10.1111/pce.14323","DOIUrl":null,"url":null,"abstract":"<p>Flavonol glycosides are bioactive compounds important for plant defence and human nutrition. Glycosylation and methylation play an important role in enriching the diversity of flavonols in response to the environment. Peach flowers and fruit are rich in flavonol diglycosides such as isorhamnetin 3-<i>O</i>-rutinoside (I3Rut), kaempferol 3-<i>O</i>-rutinoside and quercetin 3-<i>O</i>-rutinoside, and flavonol monoglycosides such as I 3-<i>O</i>-glucoside and Q 3-<i>O</i>-galactoside. UV-B irradiation of fruit significantly induced accumulation of all these flavonol glycosides. Candidate biosynthetic genes induced by UV-B were identified by genome homology searches and the in vitro catalytic activities of purified recombinant proteins determined. PpUGT78T3 and PpUGT78A2 were identified as flavonol 3-<i>O</i>-glucosyltransferase and 3-<i>O</i>-galactosyltransferase, respectively. PpUGT91AK6 was identified as flavonol 1,6-rhamnosyl trasferase catalysing the formation of flavonol rutinosides and PpFOMT1 was identified as a flavonol <i>O</i>-methyltransferase that methylated Q at the 3<i>'</i>-OH-OH to form isorhamnetin derivatives. Transient expression in <i>Nicotiana benthamiana</i> confirmed the specificity of PpUGT78T3 as a flavonol 3-<i>O</i>-glucosyltransferase, PpUGT78A2 as a 3-<i>O</i>-galactosyltransferase, PpUGT91AK6 as a 1,6-rhamnosyltrasferase and PpFOMT1 as an <i>O</i>-methyltransferase. This study provides new insights into the mechanisms of glycosylation and methylation of flavonols, especially the formation of flavonol diglycosides such as I3Rut, and will also be useful for future potential metabolic engineering of complex flavonols.</p>","PeriodicalId":222,"journal":{"name":"Plant, Cell & Environment","volume":null,"pages":null},"PeriodicalIF":6.0000,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"9","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plant, Cell & Environment","FirstCategoryId":"2","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/pce.14323","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PLANT SCIENCES","Score":null,"Total":0}
引用次数: 9
Abstract
Flavonol glycosides are bioactive compounds important for plant defence and human nutrition. Glycosylation and methylation play an important role in enriching the diversity of flavonols in response to the environment. Peach flowers and fruit are rich in flavonol diglycosides such as isorhamnetin 3-O-rutinoside (I3Rut), kaempferol 3-O-rutinoside and quercetin 3-O-rutinoside, and flavonol monoglycosides such as I 3-O-glucoside and Q 3-O-galactoside. UV-B irradiation of fruit significantly induced accumulation of all these flavonol glycosides. Candidate biosynthetic genes induced by UV-B were identified by genome homology searches and the in vitro catalytic activities of purified recombinant proteins determined. PpUGT78T3 and PpUGT78A2 were identified as flavonol 3-O-glucosyltransferase and 3-O-galactosyltransferase, respectively. PpUGT91AK6 was identified as flavonol 1,6-rhamnosyl trasferase catalysing the formation of flavonol rutinosides and PpFOMT1 was identified as a flavonol O-methyltransferase that methylated Q at the 3'-OH-OH to form isorhamnetin derivatives. Transient expression in Nicotiana benthamiana confirmed the specificity of PpUGT78T3 as a flavonol 3-O-glucosyltransferase, PpUGT78A2 as a 3-O-galactosyltransferase, PpUGT91AK6 as a 1,6-rhamnosyltrasferase and PpFOMT1 as an O-methyltransferase. This study provides new insights into the mechanisms of glycosylation and methylation of flavonols, especially the formation of flavonol diglycosides such as I3Rut, and will also be useful for future potential metabolic engineering of complex flavonols.
黄酮醇苷是植物防御和人体营养的重要生物活性化合物。糖基化和甲基化在黄酮醇响应环境丰富多样性中起着重要作用。桃花和桃果富含异鼠李素3- o -芦丁苷(I3Rut)、山奈酚3- o -芦丁苷和槲皮素3- o -芦丁苷等黄酮醇二糖苷,以及I3 - o -葡萄糖苷和Q 3- o -半乳糖苷等黄酮醇单糖苷。UV-B照射可显著诱导这些黄酮醇苷的积累。通过基因组同源性搜索确定了候选的UV-B诱导的生物合成基因,并测定了纯化后的重组蛋白的体外催化活性。PpUGT78T3和PpUGT78A2分别鉴定为黄酮醇3- o -葡萄糖基转移酶和3- o -半乳糖基转移酶。pppugt91ak6被鉴定为黄酮醇1,6-鼠李糖基转移酶,催化黄酮醇芦丁苷的形成,PpFOMT1被鉴定为黄酮醇o -甲基转移酶,在3'-OH-OH上甲基化Q,形成异鼠李素衍生物。在benthamiana中的瞬时表达证实了pppugt78t3作为黄酮醇3- o -葡萄糖基转移酶、pppugt78a2作为3- o -半乳糖基转移酶、pppugt91ak6作为1,6-鼠李糖基转移酶和PpFOMT1作为o -甲基转移酶的特异性。该研究为黄酮醇的糖基化和甲基化机制,特别是黄酮醇二糖苷如I3Rut的形成提供了新的见解,并为未来复杂黄酮醇的潜在代谢工程提供了有用的信息。
期刊介绍:
Plant, Cell & Environment is a premier plant science journal, offering valuable insights into plant responses to their environment. Committed to publishing high-quality theoretical and experimental research, the journal covers a broad spectrum of factors, spanning from molecular to community levels. Researchers exploring various aspects of plant biology, physiology, and ecology contribute to the journal's comprehensive understanding of plant-environment interactions.