The secrets of holocentric chromosome architecture and evolution

Holocentric chromosomes have centromeres distributed along their entire length, in contrast to monocentric organisation, in which the centromere is confined to a single chromosomal region. In higher plants, monocentric species predominate and more information is also available about their genomes compared to holocentric ones. 

A team of researchers led by André Marques of the Max Planck Institute for Plant Breeding Research in Cologne, Germany, and including scientists from the Biology Centre's Laboratory of Molecular Cytogenetics, used highly accurate DNA sequencing technology to decode the genomes of three closely related holocentric beak-sedges, grass-like flowering plants that occur worldwide and are often the first conquerors of new habitats. For reference, the team also decoded the genome of their most closely related monocentric relative. Their analyses revealed striking differences in genome organisation and chromosome behaviour in holocentric organisms. The study also provided new insights into the evolution and determination of centromeres, the topic that was investigated by the researches from the Biology Centre. They showed that the scattered centromeres may arise through the action of Helitrons, the mobile elements capable of capturing and moving fragments of centromeric DNA in the genome. 

Publication: Hofstatter P.G., Thangavel G., Lux T., Neumann P., Vondrak T., Novák P., Zhang M., Costa L., Castellani M., Scott A., Toegelová H., Fuchs J., Mata-Sucre Y., Dias Y., Vanzela A., Huettel B., Almeida C.C.S., Šimková H., Souza G., Pedrosa-Harand A., Macas J., Mayer K., Houben A., Marques A. (2022) Repeat-based holocentromeres influence genome architecture and karyotype evolution Cell 185: 1-16. DOI: 10.1016/j.cell.2022.06.045

Additional information: Press-releas of MPI, video explanation (5 min)