A domesticação da aveia implicou na perda de microssatélites?

Abstract

Oat is a cereal that has been standing out for its potential in agriculture, mainly due to grain production, which boasts excellent industrial quality and chemical composition, as well as various usage possibilities. This cereal is commonly grown in the Southern states of Brazil, where it shows better adaptation. In this aspect, it is one of the crops highlighted in breeding programs, aiming at increased productivity and resistance to abiotic and biotic factors for better adaptation to diverse regions. Plant evolution, evidenced by the diversity of their genomes, reflects adaptation over millions of years to different environments and selective pressures. Genomic variability in plants drives evolutionary innovation, enabling the exploration of new niches and responses to environmental challenges, such as climate change and interactions with other species, crucial for their survival and diversification over time. Microsatellites are a fundamental tool for advanced breeding studies, capable of being used in various ways to optimize the time spent developing new cultivars, as well as conducting complex studies of regions within genomes and studying intergenic and genic regions. The objectives of this dissertation are to characterize the presence of microsatellites in oat subgenomes, verify the distribution of these microsatellites in different types of genes regarding their function, and compare their presence in ancestral genomes with their presence in the cultivated hexaploid oat genome. A comparison was made of the quantity of microsatellites present in their AA, CC, and DD genomes, and the loss of these sequences due to oat domestication and evolutionary processes over the years was estimated. Microsatellites are important when associated with genes involved in vital processes, development, productivity, resistance, and/or tolerance, among others. Variations were observed among genomes of Avena sativa compared to ancestral Avena longiglumis and Avena insularis, where there was a greater loss of monomer and dimer microsatellites, and conservation of microsatellites within genes in the DD genomes of Avena sativa compared to Avena insularis, showing non-uniformity among genomes. The differential presence of microsatellites in ancestral genomes and cultivated hexaploid oat suggests that selection over time was not uniform in the three oat genomes, with more significant reductions of microsatellites occurring in the AA and CC genomes, particularly within genes.