Biosynthetic gene clusters – Institut for Plante- og Miljøvidenskab - Københavns Universitet

Biosynthetic gene clusters

A recent theme in plant biology is that non-homologous genes involved in the biosynthesis of a specific chemical defense compound can be organized in a gene cluster. This genomic co-localization is observed for several classes of chemical defense compounds, such as terpenoids, benzoxazinoids, and alkaloids. We reported the independent formation of cyanogenic glucoside biosynthetic gene clusters in three plant lineages (Plant J. 68: 273).

The repeated organization of these biochemical genes in gene clusters suggests the existence of an evolutionary mechanism driving this process. The pathways for chemical defense compounds can provide both costs and benefits and are under variable and opposing selection pressures. Consequently, adaptive polymorphisms are observed in nature. Chromosomal modifications that reduce recombination between the genes that make up a functional pathway have a selective advantage and this progressively leads to gene cluster formation (Trends in Plant Science 17: 383).

The existence of plant biosynthetic gene clusters has great potential for the identification of entire biosynthetic pathways for plant bioactive compounds of pharmaceutical interest, and we are exploring these options.

The gene cluster for cyanogenic glucoside biosynthesis in cassava (Manihot esculenta)

Selected publications

Takos A.M., Rook F. (2012). Why biosynthetic genes for chemical defense compounds cluster. Trends in Plant Science, 17: 383-388.

Takos A.M., Knudsen C., Lai D., Kannangara R., Mikkelsen L., Motawia M.S., Olsen C.E., Sato S., Tabata S., Jørgensen K., Møller B.L., Rook F. (2011). Genomic clustering of cyanogenic glucoside biosynthetic genes aids their identification in Lotus japonicus and suggests the repeated evolution of this chemical defence pathway. Plant J. 68: 273-286.