Study discloses the role of gene cluster variants in producing climate-specific natural substances

Natural substances, the biologically active components made by organisms, are of much interest to scientists mainly as the basis for medicines, as some natural substances exhibit antibacterial, antiviral, and antitumor properties.

Image Credit: Senckenberg Biodiversity and Climate Research Center

Organisms also produce natural substances to better cope with the environment. For instance, certain lichen species produce parietin, the orange pigment, to safeguard themselves against UV radiation. Yet, many functions of the natural substances identified until now are entirely unknown.

The genetic material of fungi that form part of lichens indicates that there are numerous undiscovered natural substances.

In fungi, we know of up to 80 groups of genes per species, so-called gene clusters that are responsible for natural substance production. That is a much higher number than the natural substances that what we have been able to detect to date from an organism.”

Imke Schmitt, Professor, Senckenberg Biodiversity and Climate Research Centre

Professor Imke Schmitt carries out research at the Senckenberg Biodiversity and Climate Research Center (SBiK-F) and the LOEWE Center for Translational Biodiversity Genomics (LOEWE-TBG). Schmitt teaches at the Goethe University in Frankfurt.

To identify if the capability of an organism to produce natural substances varies under contrasting environments, Schmitt and associates gathered the umbilicate lichen Umbilicaria pustulata at the base and the summit of mountains in Spain and Italy. They sequenced the samples and matched the natural substance-associated gene clusters in their genomes.

We found three gene cluster variants in Umbilicaria pustulata that are either unique to the Mediterranean climate at the base of mountains or to the temperate climate at higher elevations. This suggests that these genes are associated with natural substances that play a role in climate adaptation. It is now particularly exciting for us to find out which natural substances are associated with these climatically differentiated gene clusters.”

Dr Garima Singh, Study Lead Author and Scientist, Senckenberg Biodiversity and Climate Research Centre

Although the genome provides information about the different natural substances an organism can produce, the distribution of genes in natural populations could be used to conclude the gene cluster variants needed in a particular climate zone.

Gene cluster variants identified on the cool mountain peaks help the lichen produce substances that serve as an antifreeze, while gene cluster variants functional at the base of mountains in Mediterranean climates with hot, long, dry summers may be associated with natural substances that aid the lichen endure drought.

The lichens’ ability to produce natural substances that make it easier or even possible for them to survive in a specific climatic niche shows us that we do not yet know the true potential of lichens at all. Perhaps we will one day be able to make climate-specific natural substances commercially viable, similar to medicines.”

Imke Schmitt, Professor, Senckenberg Biodiversity and Climate Research Centre

“Studying the genomes of lichens can help us find new natural substances with useful properties. However, if individual lichen populations become extinct due to climate change or human intervention, the genetic basis for the production of as yet undiscovered natural products may disappear with them,” added Singh.