过表达NtMYC2对烟草多酚物质合成及盐胁迫抗性的影响

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中图分类号：S572.03 文献标识码：A

文章编号：1007-5119（2025）03-0029-08

Effects of NtMYC2 Overexpression on Polyphenol Synthesis and Salt Stress Resistance in Tobacco

QU Xiaoling， CHEN Shuai， LI Xiuchun， YANG Aiguo， REN Min， TONG Ying， WU Xiuming， SUN Yangyang （Institute of Tobacco Research， Chinese Academy of Agricultural Sciences， Qingdao 266101， China）

Abstract：InthisstudytheNtMC2transeriptionfactorwassuccefullylonedviaomologousconing.Toanalyzeitsbological functionsinpolyphenolbiosynthesisandsaltstressresistance，weemployedRealtimePCRtoanalyzeitsregulatoryefecton NtCHS1，a keyrate-limitingenzymegeneinflavonoid biosynthesis.NtMYC2-overexpressionlines wereconstructed，andthe diferences inpolyphenolicsubstancesandkeyenzymegenesbetweetheNMYC2-overexpresionlinesandthewild-typelineswere analyzed.ThegerminationrateandresistancephysiologicalindicatorsoftobaccoseedsundersaltstresswerealsodeterminedThe results showed that NtMYC2transcription factorlocalizes tothenucleusandfunctionsasapositiveregulator，ativatingthe transcriptionalactivityofthe NCHS1gene promoter.Overexpressionof NMYC2 significantlyupregulated theexpressonlevelof severalkeystructuralenzymegenes involved inpolyphenolsbiosynthesis pathway，uchasPALandCHS，leadingtosignificantly increasedlevelsofogenccidcorogeicciddtotetinasgicaccoes.rtoredh the wild-type controls，under 100mmol/L NaCl treatment， the germination rate of NtMYC2-overexpressing transgenic lines was significantly increased. Under 200 mmol/L NaCl stress， the MDA and H2O2 content of NtMYC2-overexpressing transgenic lines were significantlyrduced，hile teODandAPXactivitiesweresigniicantlyincreased.InummaryNMC2positielygulateskey polyphenolsythesisgenes，enancingthesthesisofpolypheolicsubstances，andpotentiallhacingplatsalttrssistace through improved oxidative stress tolerance.

Keywords： Nicotiana tabacum; NtMYC2; expression regulation; polyphenol synthesis; salt stress resistance

多酚类化合物是一类广泛存在于植物中的次生代谢物质，目前已经从植物中分离鉴定出近万种，按结构大致可分为类黄酮、芪类、酚酸类和木酚素类。（剩余12029字）