They create the first genetic map of the repeated DNA sequences of wheat

Wheat is one of the most important agricultural crops worldwide. It accounts for 20% of the calories consumed daily and is an important source of protein. Demand for wheat is estimated to be 60% higher in 2050 due to global population growth, although unfortunately, production could decline by 27% in the future due to high temperatures and water scarcity. In a global warming scenario, it is necessary to develop better adapted wheat varieties to preserve fertility and increase the sustainable production of this crop.

Researchers from the Institute of Sustainable Agriculture (IAS) of the Higher Council for Scientific Research (CSIC) and the University of Granada (UGR) have developed the first bread wheat satelitome, the genetic map of repeated DNA sequences, also known as satellite DNA , an important advance towards the development of wheat varieties more resistant to global warming.

Understanding the organization of the wheat genome is crucial in the field of plant genetic improvement. Specifically, it is very important to generate knowledge about the reproductive biology processes of wheat such as meiosis, cell division that generates gametes in sexually reproducing organisms. “Meiosis is a fundamental process because it ensures the fertility and, therefore, the production of plants. During meiosis, the chromosomes recognize each other and associate in pairs so that the gametes are viable and the plants are fertile, and therefore produce grain,” explains IAS researcher Pilar Prieto.

“In previous studies in our laboratory we have determined that the interaction between chromosomes begins at their ends, the subtelomeres and the telomeres. In this work we have identified the DNA sequences located at the ends of the wheat chromosomes and that can intervene in the recognition and association events between chromosomes. We have developed the first satellitome of bread wheat, the genetic map of repeated DNA sequences or also known as satellite DNA,” highlights Prieto, who explains that “in this work we have determined that subtelomeres are rich in satellite DNA. Furthermore, we have verified that chromosomes differ among themselves in the nature, number and distribution of satellite DNA sequences, which can contribute to specificity and that only identical chromosomes are capable of recognizing and associating in pairs in meiosis, ensuring fertility. of wheat.”

Wheat field. (Photo: USDA Agricultural Research Service)

The work developed by IAS researchers is important to understand how chromosomes recognize and associate during meiosis. “This way we can contribute to developing tools that facilitate chromosome manipulation and genetic transfer from one species to another and develop wheat varieties better adapted to high temperatures or water scarcity in a global warming scenario,” highlights Prieto.

The study, whose first signatory is Ana Gálvez Galván of the IAS, is titled “Bread wheat satellitelitome: A complex scenario in a huge genome.” And it has been published in the academic journal Plant molecular biology. (Source: CSIC)