News
Tomato genome explains evolutionary success of fleshy-fruited plants

May 31, 2012, Barcelona, Spain — Researchers at the Centre for Genomic
Regulation (CRG) have participated in the sequencing of the tomato
genome.

May 31, 2012, Barcelona, Spain — Researchers at the Centre for Genomic Regulation (CRG) have participated in the sequencing of the tomato genome.

This project was conducted by an international consortium with the principal aim of providing the tomato genome sequence to public and private research groups in order to gain a better understanding of the biology of this agriculturally essential plant.

The results obtained by the consortium are presented in the journal Nature and describe the regions of the tomato genome that have been key to its evolution and specialization. The study compares the genome of the cultivated tomato (Solanum lycopersicum) with two species of the same genus, the wild tomato (Solanum pimpinellifolium) and the potato (Solanum tuberosum).

By comparing the genomes of these species, researchers have observed that the genomes of the cultivated and wild tomatoes differ by only 0.6 per cent.
 
However, the divergence between the genomes of the tomato and potato is more than eight per cent. This is because, throughout their evolution, they have inverted and triplicated long fragments of their genome. These genomic reorganizations explain evolutionary changes that occurred millions of years ago and contributed to the emergence of new species of plants with fruits and their subsequent diversification.

Moreover, it has been seen that some repeated fragments include genes that would be responsible for, among other things, the control of certain characteristics of the texture of the fruit such as the formation of the skin. These repetitions have helped to form a tougher skin in order to preserve the fruit better.

“The tomato is one of the most common and most exploited crop plants,” explains Francisco Cámara, one of the researchers who participated in the tomato genome project from the Bioinformatics and Genomics lab at the CRG, led by Roderic Guigó.

“Getting to know its genome in detail allows us, on one hand, to have a better understanding of the evolution of higher plants thanks to controlled populations such as cultivated ones, and it also provides new tools for future agriculture.”

Guigó was one of the researchers who participated in the first sequencing of the human genome and he has been involved in numerous sequencing projects. His lab contributed to the tomato genome project by developing software to identify genes in the genome sequence of the tomato. Genes are the basic units of information and generally constitute a very small percentage of the genome sequence of a species.

“The identification of genes is the first step in converting the genome sequence of a species into biologically relevant information,” adds Guigó.

This project was conducted by an international consortium with the involvement of several European research groups from the UK, Belgium, Germany, Italy, the Netherlands and Spain, along with other international groups in China, Japan, Korea, Taiwan, India, Argentina and the United States.

In Spain, as well as the Centre for Genomic Regulation (CRG), the Institute of Molecular and Cellular Biology of Plants-UPV-CSIC, the “La Mayora” Subtropical and Mediterranean Horticulture Institute UMA-CSIC, the Barcelona Supercomputing Centre, the Institute for Biomedical Research (IRB) and the company Sistemas Genómicos in the Technology Park of Valencia also all took part.