Format: ORAL

Andrea Pedrosa-Harand1, Yennifer Mata-Sucre1,2, Yhanndra Dias1,3, Lucas Costa1, Mariela A. Sader4, Mariana Bez5, Thassa Boldieri de Souza6, Letcia Maria Parteka6, Gokilavani Thangavel2, Yi-Tzu Kuo3, Veit Schubert3, Jrg Fuchs3, Christopher E. Buddenhagen7, Andr Vanzela6, Gustavo Souza1, Andr Marques2, Andreas Houben3

1 Laboratory of Plant Cytogenetics and Evolution, Department of Botany, Federal University of Pernambuco, Recife-PE, Brazil 2 Max Planck Institute for Plant Breeding Research, Cologne, Germany 3 Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Germany 4 Instituto Multidisciplinario de Biología Vegetal (IMBIV), Universidad de Córdoba-CONICET, Córdoba, Argentina 5 Plant Breeding Department, University of Bonn, Bonn, Germany 6 Laboratório de Citogenética e Diversidade de Plantas, Departmento de Biologia Geral, Universidade Estadual de Londrina, Londrina-PR, Brasil 7 AgResearch, Agro-ecology, Ruakura, New Zealand

While most species have monocentric chromosomes with a regionally restricted centromere, holocentromeres show centromere activity along the entire chromosome. Holocentromeres evolved independently at least 14 times across plant and animal groups. Among plants, the cyperid clade (Poales) comprises the highest number of species with holocentric chromosomes. However, based on recent findings, the transition from mono-to-holocentricity occurred in this clade multiple times, because lineages with mono- or holocentric chromosomes exist. Independent transitions to holocentricity resulted in different adaptations of the centromere and genome structures in these different groups of species, giving insights into variable centromere plasticity and function. We will review our recent findings regarding the centromere organization and the role of different classes of repeats in chromosome evolution in monocentric and holocentric Thurniaceae, Juncaceae and Cyperaceae species, and discuss the diversification of this group from a cytogenomic perspective.