一氧化氮信号在脱落酸诱导丹参酚酸类成分积累中的作用

Role of NO signal in ABA-induced phenolic acids accumulation in Salvia miltiorrhiza hairy roots

摘要:

为探讨一氧化氮 (Nitric oxide，NO) 信号在脱落酸 (Abscisic acid，ABA) 诱导丹参酚酸类成分积累中的作用，采用不同浓度一氧化氮外源供体硝普钠 (Sodium nitroprusside，SNP) 处理丹参毛状根，6 d后采收，测定酚酸类成分含量；ABA联合一氧化氮清除剂 (2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl- 3-oxide，c-PTIO) 或一氧化氮合酶抑制剂 (NG-nitro-L-arginine methyl ester，L-NAME) 对丹参毛状根进行处理，测定酚酸类成分含量和关键基因表达量。结果表明，100 μmol/L SNP对丹参毛状根中迷迭香酸与丹酚酸B积累的诱导效果最显著，迷迭香酸和丹酚酸B含量分别增加了3倍和4倍。ABA处理能显著促进PAL (Phenylalanine ammonia lyase)、TAT (Tyrosine aminotransferase) 和RAS (Rosmarinic acid synthase) 基因的表达，促进丹参毛状根中酚酸类成分的积累，而联合c-PTIO或L-NAME共同处理后，3种关键基因表达下调，并显著抑制了酚酸类成分的积累。研究证明NO和ABA均能够促进丹酚酸类成分的积累，NO信号可能介导了ABA对丹酚酸生物合成的诱导作用。

Abstract:

To investigate roles of nitric oxide (NO) signal in accumulations of phenolic acids in abscisic acid (ABA)-induced Salvia miltiorrhiza hairy roots, S. miltiorrhiza hairy roots were treated with different concentrations of sodium nitroprusside (SNP)-an exogenous NO donor, for 6 days, and contents of phenolic acids in the hairy roots are determined. Then with treatment of ABA and NO scavenger (2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethylimidazoline-1- oxyl-3-oxide, c-PTIO) or NO synthase inhibitor (NG-nitro-L-arginine methyl ester, L-NAME), contents of phenolic acids and expression levels of three key genes involved in phenolic acids biosynthesis were detected. Phenolic acids production in S. miltiorrhiza hairy roots was most significantly improved by 100 μmoL/L SNP. Contents of RA and salvianolic acid B increased by 3 and 4 folds. ABA significantly improved transcript levels of PAL (phenylalanine ammonia lyase), TAT (tyrosine aminotransferase) and RAS (rosmarinic acid synthase), and increased phenolic acids accumulations. However, with treatments of ABA+c-PTIO or ABA+L-NAME, accumulations of phenolic acids and expression levels of the three key genes were significantly inhibited. Both NO and ABA can increase accumulations of phenolic acids in S. miltiorrhiza hairy roots. NO signal probably mediates the ABA-induced phenolic acids production.