Mariela Sader
Multidisciplinary Institute of Plant Biology (IMBIV-CONICET), Córdoba - Argentina
Diversity of the repetitive DNA fraction in Solanum betaceum Cav. (SOLANACEAE)
Variation in genome size and chromosomal number and morphology are recurrent events in angiosperms, associating such characteristics with evolutionary events and speciation in plants. Eukaryotic genomes comprise a significant portion of various classes of repetitive DNA sequences. Repetitive DNA is one of the main contributors to genome size variation in higher plants, accounting for 50 to 90% of the total genome. The evolution of repetitive DNA sequences has provided information about different processes that acted in the speciation and domestication of species of interest. Analyzing the chromosomal distribution of repetitive DNA sequences will allow exploration of aspects of genomic differentiation, providing chromosomal/molecular markers relevant for inter-specific and inter-populational relationships analysis. In this seminar, I will present the tomato tree, and relatives, repetitive genome fraction. Solanum betaceum is native to the Andean region of South America and is found today in semi-wild state in northwestern Argentina. It is popular in this region as it is consumed in juices and as a fresh fruit. Solanum betaceum has a large genome size. To understand the repetitive fraction composition, we used RepeatExplorer and localized the most abundant repeats by fluorescence in situ hybridization (FISH). Tomato tree showed an accumulation of repetitive DNA sequences, especially retrotransposons, and a relative low abundance of satDNA.
