Abstract
4-Coumaric acid: coenzyme A ligase (4CL) is a key enzyme in the phenylpropanoid metabolic pathway that regulates the biosynthesis of lignin and flavonoids. Therefore, the study of 4CL is important to explore the accumulation and regulation of metabolites. This study investigated the role that the 4CL2 gene from Dryopteris fragrans (Df4CL2) plays in the metabolite synthesis. Changes in gene expression, enzyme activity, and the content of lignin and flavonoids were measured in different tissues of tobacco as model plant that was successfully transferred with Df4CL2. Tobacco plants with Df4CL2 (transgenic tobacco, TT) were successfully obtained via the Agrobacterium-transformation method. This TT tended to be thicker and had an earlier flowering period than wild type tobacco (WT). The expression levels of Df4CL2 were higher in the stem, leaf, and root in TT compared to WT. In addition, compared to WT, TT had higher 4CL enzyme activity and higher lignin and flavonoids contents. This suggests that Df4CL2 is involved in the synthesis of lignin and flavonoids in D. fragrans. This research provides important evidence toward understanding the phenylpropanoid metabolic pathway in ferns.
Highlights
The secondary metabolic pathways of phenylpropanoid have been studied in detail, especially in angiosperms, where the metabolic pathway has been explored in detail (Dixon et al, 2002; Hamberger and Hahlbrock, 2004)
In this particular metabolic pathway, 4-Coumaric acid: coenzyme A ligase (4CL; EC 6.2.1.12) is a key enzyme, located in the transition from the general pathway to the downstream branch pathway (Vassão et al, 2010; Gui et al, 2011). 4CL uses cinnamic acid, 4-coumaric acid, 5-hydroxyferic acid, sinapic acid, caffeic acid, and ferulic acid as substrates to form the corresponding acyl-CoA thioester in the presence of ATP and Mg2+. These become substrates in different downstream branch pathways. 4CL generally exists as an isozyme in different plants and has different substrate preferences. It regulates the amount of CoA esters by catalyzing different substrates, or it enters the lignin biosynthesis-specific pathway through a reaction catalyzed by cinnamoyl-CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD). 4CL can enter flavonoids
The in-depth study of the 4CL gene and enzyme activity has an important role in the process of plant growth and development, as well as in growth in adverse environments, but it provides an important guidance in the production and regulation of secondary metabolites (Blach-Olszewska et al, 2008). 4CL has been studied in angiosperms, gymnosperms, and bryophytes; in ferns, its metabolic pathway and function remains not clearly identified
Summary
The secondary metabolic pathways of phenylpropanoid have been studied in detail, especially in angiosperms, where the metabolic pathway has been explored in detail (Dixon et al, 2002; Hamberger and Hahlbrock, 2004) In this particular metabolic pathway, 4-Coumaric acid: coenzyme A ligase (4CL; EC 6.2.1.12) is a key enzyme, located in the transition from the general pathway to the downstream branch pathway (Vassão et al, 2010; Gui et al, 2011). These become substrates in different downstream branch pathways. The in-depth study of the 4CL gene and enzyme activity has an important role in the process of plant growth and development, as well as in growth in adverse environments, but it provides an important guidance in the production and regulation of secondary metabolites (Blach-Olszewska et al, 2008). 4CL has been studied in angiosperms, gymnosperms, and bryophytes; in ferns, its metabolic pathway and function remains not clearly identified
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
