Arabidopsis: An Ideal Platform for Understanding Secondary Metabolites

Xu “Sirius” Li, PhD, (bio page) an assistant professor and plant metabolic pathway engineer with N.C. State University’s Plants for Human Health Institute (PHHI), uses the model plant system Arabidopsis to understand how plants produce secondary metabolites and support human health. In collaboration with other scientists at PHHI and at the N.C. Research Campus, he is applying that knowledge to real-world needs.

Flavonoids are one of the most abundant secondary metabolites in plants.

Secondary metabolites are the collection of chemicals inside plants that protect them and when consumed by humans have health benefits. For example, flavonoids in plants produce yellow, red and blue pigmentation; help defend against microbes, fungi and insects; are involved with ultra-violet light filtration; serve as chemical messengers; and perform other physiological functions.

For humans, the consumption of flavonoids in fruits, vegetables, teas and wines are shown in research studies to have anti-inflammatory, antioxidant, antimicrobial and even anti-cancer health effects.

The challenge for scientists is two-fold. First, continuing to expand the understanding of how plants produce secondary metabolites and support human health; second, applying the knowledge to real-world needs. Xu “Sirius” Li, PhD, (pictured right) is one scientist who has taken on both sides of the challenge using the plant model system Arabidopsis.

Expanded Understanding

Li, who is an assistant professor and plant metabolic pathway engineer with N.C. State University’s Plants for Human Health Institute (PHHI) at the NC Research Campus in Kannapolis, specifically researches the phenylpropanoid pathway, which is responsible for the biosynthesis of a variety of compounds including flavonoids.

“The idea is to look for associations between metabolite variation and genetic variation across individual plants to figure out what genes control what metabolites,” Li related. “The whole genome sequence for a large collection of Arabidopsis accessions are available, so all we need to do is metabolite profiling and association analysis.”

Linking genes and metabolites is a crucial step in knowing how plants make specific compounds. “Once we identified a metabolite-gene association, we will need to validate it,” Li stated. “Arabidopsis is an ideal platform to do that. Such validation is often not feasible or takes a long time to do in crops. With Arabidopsis, in a few months, you know the answer.”

Real-World Applications