Chinese liquorice (Glycyrrhiza uralensis) contains perennial herbal legumes that are frequently used in Chinese Traditional Medicine and as a natural sweetener, noted researchers from the RIKEN Center for Sustainable Resource Science in Japan in The Plant Journal.
They added: “Experimental and clinical studies have demonstrated that liquorice has a wide range of pharmacological properties such as anti-inflammatory, antiviral, antimicrobial, antioxidative, antidiabetic, antiasthma and anticancer activities as well as immunomodulatory, gastroprotective, hepatoprotective, neuroprotective and cardioprotective effects.”
However, they pointed out that only a small fraction of the immensely diverse metabolism of such plants has been explored to aid nutraceutical and medicinal use.
The team chose to examine the genome of Chinese liquorice rather than other related species partly because it is known to contain the highest concentration of glycyrrhizin, a compound that is associated with the medical properties of the plant, which include anti-inflammatory, anti-cancer, anti-allergic, and anti-viral activities.
To conduct the screening, they chose a strain of G. uralensis kept at the Takeda Garden for Medicinal Plant Conservation in Kyoto.
Using a combination of long read and short read sequencing, and by comparing the genome to published sequences of other legume species, they predicted that the plant's genome coded just over 34,000 proteins, a number higher than the 20,000 in the human genome.
“The present study will provide the first reference genome resource, which should be valuable for the identification, isolation and editing of useful genes to improve agronomic and medicinal traits in liquorice,” states the study.
“Population sequencing methods with the draft genome will enable us to identify key genetic factors in association with important traits such as the chemical properties of bioactive compounds, rhizome and root productivity, environmental stress tolerances and disease resistance.”
Keiichi Mochida, the first author of the paper, said: "Chinese liquorice is an important and heavily consumed medicinal plant, and we hope that our work will make it possible to carry out molecular breeding to create strains that will grow sustainably in Japan, and which produce large concentrations of useful compounds such as glycyrrhizin."
The group plans to do further work to examines differences between the genome of G. uralensis and other liquorice species, to further deepen their understanding of the production of useful compounds.
The work was carried out by RIKEN CSRS in collaboration with a group including Chiba University, Kochi University, and Osaka University.
Source: The Plant Journal
“Draft genome assembly and annotation of Glycyrrhiza uralensis, a medicinal legume.”
Author: Keiichi Mochida, et al