水曲柳FmCCoAOMT基因在木质素合成及非生物胁迫中的功能分析

Functional Analysis of FmCCoAOMT Gene in Fraxinus mandshurica During Lignin Synthesis and Abiotic Stress

为了明确FmCCoAOMT基因的功能,以水曲柳(Fraxinus mandshurica)为材料,利用qRT-PCR方法分析FmCCoAOMT基因的表达模式,结果显示FmCCoAOMT基因具有组织特异性。在雌株和雄株多年生木质部的表达量最高,其中在雄株中是新生枝皮表达量的9.4倍,在雌株中是叶片表达量的13.1倍。采用叶盘法获取转基因烟草(Nicotiana tabacum)植株,过表达FmCCoAOMT的烟草与野生型相比,木质素含量升高41%,纤维素和半纤维素含量分别降低32%和52%。非生物胁迫处理后过表达FmCCoAOMT烟草相比于野生型,POD和SOD活性增加,MDA含量下降,且活性氧含量减少,其中NaCl处理后,POD活性比对照组升高83%;NaCl、ABA和甘露醇处理后,SOD活性比对照组分别升高56.6%、44.2%和19.0%,MDA含量比对照组分别降低了77.2%、11.7%和47.6%。结果表明FmCCoAOMT基因通过参与木质素合成,促进非生物胁迫适应能力。

To clarify the function of FmCCoAOMT gene,the expression pattern of FmCCoAOMT gene was analyzed by qRT-PCR using Fraxinus mandshurica as material in this study.The results showed that FmCCoAOMT gene was tissue specific.The expression level was the highest in the xylem of both female and male perennial plants,and was 9.4 times higher than that in the bark of new shoots in male plants,and was 13.1 times higher than that of leaf in female plants.The leaf disk method was used to obtain transgenic tobacco plants.Compared with the wild type,the lignin content of overexpressing FmCCoAOMT was increased by 41%,while the cellulose and hemicellulose contents were decreased by 32%and 52%,respectively.Tobacco overexpressing FmCCoAOMT after abiotic stress treatment compared to wild type,the activity of POD and SOD increased,the content of MDA decreased,and the content of reactive oxygen decreased after stress treatment.After NaCl treatment,POD activity was 83%higher than that of control group.After NaCl,ABA and mannitol treatments,SOD activity increased by 56.6%,44.2%and 19.0%,and MDA content decreased by 77.2%,11.7%and 47.6%,respectively.The results indicated that FmCCoAOMT gene might be involved in lignin synthesis of F.mandshurica,promoted abiotic stress tolerance.