“Genetic Goldmine” found in one of the toughest environments on Earth

The Atacama Desert is the hardest place to survive, the genes that help plants to live in extreme weather might be the ‘Genetic Goldmine’ and the key to surviving climate change.

The Atacama Desert in northern Chile, which is located between the Pacific Ocean and Andes Mountains, is the driest place on the planet. Still the plant’s growth rate there is high, including grasses, annuals, and perennial shrubs. The desert has a limited water supply, plants in the Atacama cope with high altitude, low obtainability of nutrients in the soil, and extremely high radiation from sunlight.

“In an era of accelerated climate change, it is critical to uncover the genetic basis to improve crop production and resilience under dry and nutrient-poor conditions,” said Gloria Coruzzi, Carroll & Milton Petrie Professor in the New York University (NYU) Department of Biology and Center for Genomics and Systems Biology, who co-led the study with Rodrigo Gutiérrez.

“Our study of plants in the Atacama Desert is directly relevant to regions around the world that are becoming increasingly arid, with factors such as drought, extreme temperatures, and salt in water and soil posing a significant threat to global food production,” said Gutiérrez, professor in the Department of Molecular Genetics and Microbiology at Pontificia Universidad Católica de Chile.

The Chilean research team has developed a “natural laboratory” in the Atacama Desert over a 10-year period, the lab has collected and characterized the climate, soil, and plants at 22 sites in different vegetational areas and elevations (every 100 meters of altitude) along the Talabre-Lejía Transect.

In order to identify the genes whose protein sequences were modified in the Atacama species, the researchers at NYU next steered an analysis using a method called phylogenomics, in which they associated the genomes of the 32 Atacama plants with 32 non-adapted but genetically alike “sister” species.

“The goal was to use this evolutionary tree based on genome sequences to identify the changes in amino acid sequences encoded in the genes that support the evolution of the Atacama plant adaptation to desert conditions,” said Coruzzi.

“This computationally intense genomic analysis involved comparing 1,686,950 protein sequences across more than 70 species. We used the resulting super-matrix of 8,599,764 amino acids for phylogenomic reconstruction of the evolutionary history of the Atacama species,” said Gil Eshel, who conducted this analysis using the High-Performance Computing Cluster at NYU.

“By studying an ecosystem in its natural environment, we were able to identify adaptive genes and molecular processes among species facing a common harsh environment,” said Viviana Araus of the Pontificia Universidad Católica de Chile in Gutierrez’ lab and a former postdoctoral associate at NYU’s Center for Genomics and Systems Biology.

“Most of the plant species we characterized in this research have not been studied before. As some Atacama plants are closely related to staple crops, including grains, legumes, and potatoes, the candidate genes we identified represent a genetic goldmine to engineer more resilient crops, a necessity given the increased desertification of our planet,” said Gutiérrez.