過表達NtMYC2對煙草多酚物質合成及鹽脅迫抗性的影響

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中圖分類號：S572.03 文獻標識碼：A

文章編號：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

多酚類化合物是一類廣泛存在于植物中的次生代謝物質，目前已經(jīng)從植物中分離鑒定出近萬種，按結構大致可分為類黃酮、芪類、酚酸類和木酚素類。（剩余12029字）