Cecílio, Leonor MoraisAlves, Sofia Graça Barbosa2011-05-312011-05-312010http://hdl.handle.net/10400.5/3327Mestrado em Biologia Funcional - Instituto Superior de AgronomiaFagaceae is an important forest trees family to which belong the genus Fagus, Quercus and Castanea. In this family, the species with great importance in the Portuguese ecosystems include Quercus ilex subsp. rotundifolia (Holm oak) and Quercus suber (cork oak) in montado, and Castanea sativa (chestnut) and Fagus sylvatica (beech) in the forests. Eukaryote genomes are particularly rich in repetitive sequences, such as retroelements that assume a major role in its structure and evolution. In this work it was characterized eleven AFLP fragments of Quercus ilex subsp. rotundifolia genome. The sequences studied were mostly homologous to retroelements while others don’t show any homology. To compare the genomic organization of some of these sequences in Fagaceae, the amplification of inter-sequence AFLP regions, was held in Holm and cork oaks, chestnut and beech DNAs. Different patterns were detected between these genomes, reflecting the evolutionary differences between species. When the genomic regions were mapped in chromosomes and nuclei on the four species, besides their occurrence throughout the nucleus, there was also a notable presence in all nucleolar organizing regions (NOR) enlightening the great contribution of retroelements and other repetitive sequences for a genomic organization not commonly seen in the plant genomes.porQuercusCastaneaFagaceaeretrotransposonsNORsfluorescence in situ hybridizationretrotransposõeshibridação in situ fluorescentemaster thesis