Researchers discover a genome that provides an understanding of diterpenoids

Salvia officinalis (S. officinalis), known as sage or common sage, and the Chinese sage (S. miltiorrhiza), or Danshen (red sage) in Chines, pertain to the Lamiaceae family and have been grown for medicinal purposes for a long time in Europe and East Asia, respectively.

A recent high-quality genome of sage was produced by an international group of scientists from China (CAS Center for Excellence in Molecular Plant Sciences, Shanghai Chenshan Botanical Garden, and Fudan University) and the UK (John Innes Centre), which also disclosed the evolutionary characteristics of Salvia’s diterpenoids biosynthesis. Cell Reports has released the study.

The Mediterranean native S. officinalis generates diterpenoids in both the tissues of the root and the shoot (leaf). S. miltiorrhiza, an East Asian plant, exclusively accumulates a particular class of diterpenoid quinones in the root. These compounds are known as tanshinones.

These two species’ genomes were compared, and it was discovered that they both have a gene cluster for diterpene production.

In S. officinalis, the BGC is home to two sets of genes that regulate the production of diterpenoid compounds in the root and shoot, respectively. In contrast, in S. miltiorrhiza, one portion of the gene cluster has shrunk and the shoot diterpene pathway has been missed, which restricts the diterpene metabolites to the root.

According to a phylogenomic study, the Salvia clades split off in the early Miocene. Several Salvia species are perennial shrubs in the Mediterranean and Europe, however, most species in East Asia are herbaceous perennials that survive the cold and wet winter using storage roots.

Notably, the shoot diterpene pathway has been eliminated in Chinese sage S. miltiorrhiza and one portion of the gene cluster has shortened.

It is advantageous for molecular breeding and the cultivation of medicinal plants to have a genomic understanding of the patterning of the production of specialized metabolites in plants that are connected with growth habits from changes in gene cluster compositions and compound structures.