玉米木质素合成途径基因ZmCCoAOMT1功能研究及转录组分析OA北大核心CSTPCD

Silage corn with high-quality roughage source for animal husbandry is an excellent forage crop.Caffeoyl-CoA-O-methyltransferase(CCoAOMT),a key methyltransferase,plays an important role in the lignin synthesis.In this study,the EMS single-base mutant of ZmCCoAOMT1 gene was obtained from EMS mutant library of corn inbred line B73,and the function of ZmCCoAOMT1 was demonstrated based on phenotypic analysis,physiological and biochemical analysis and gene expression analysis.It was found that the mutation of ZmCCoAOMT1 reduced the degree of lignification,significantly decreased the stem lignin content,and declined G(guaiacyl lignin)and S(syringa lignin)monomers contents,whereas increased in vitro digestibility of dry matter.The expression of ZmCCoAOMT1 in the stalks of the mutant was significantly reduced compared to the wild type.Transcriptome analysis analysis showed that the mutation of ZmCCoAOMT1 gene might change the expression of related genes involved in the phenylpropanoid metabolic pathway,leading to variation in lignin content and monomer composition.Therefore,ZmCCoAOMT1 gene would be valuable in corn breeding for high-digestibility and high-quality silage,and above results provided an important genetic basis for elucidating the mechanism of lignin anabolic pathway.