A high-quality genome assembly of the tetraploid Teucrium chamaedrys unveils a recent whole genome duplication and a large biosynthetic gene cluster for diterpenoid metabolism 

Plant Commun. 2025 Jun 3:101393. doi: 10.1016/j.xplc.2025.101393. Online ahead of print.

ABSTRACT

Teucrium chamaedrys, also called wall germander, is a small woody shrub native to the Mediterranean region. Its name is derived from the Greek words meaning ‘ground oak’, since its tiny leaves resemble those of an oak tree. Teucrium species are proliferative producers of diterpenes, which afford them valuable properties widely co-opted in traditional and western medicines. Sequence and assembly of the 3 Gbp tetraploid T. chamaedrys revealed 74 diterpene synthase genes, with the vast representation of these diterpene synthases clustered along four genomic loci. Comparative genomics revealed that this cluster is mirrored in the closely related species, Teucrium marum. Along with the presence of several cytochrome p450 sequences, this region is the one of largest biosynthetic gene clusters identified. Teucrium is well known for accumulating clerodane-type diterpenoids which are produced from a kolavanyl diphosphate precursor. To elucidate the complex biosynthetic pathways of these medicinal compounds, we identified and functionally characterized several kolavanyl diphosphate synthases from T. chamaedrys. Its remarkable chemistry and tetraploidy make T. chamaedrys an interesting and unique model for studying genomic evolution and adaptation in plants.

PMID:40468595 | DOI:10.1016/j.xplc.2025.101393