Robert Hasterok
Plant Breeding, Plant Science and Plant Genetics
Title: Dissecting grass genome organisation at the cytomolecular level using the model genus Brachypodium
Biography
Biography: Robert Hasterok
Abstract
Modern molecular cytogenetics combines various methodological approaches of cytology, molecular genetics and advanced digital image analysis. It focuses on the study of nuclear genomes at the microscopic level. The cytomolecular organisation of plant genomes is still rather poorly investigated, compared to that of animals. Most plant genomes, including those of economically and ecologically crucial cereals and forage grasses, are usually large and saturated with repetitive DNA, which hampers detailed molecular cytogenetic analyses. Model organisms possess a combination of features, which makes them more amenable to scientific investigation than others. One of the most recent and rapidly developing model systems are representatives of the Brachypodium genus, particularly B. distachyon. They possess small, and in some cases, already sequenced genomes with a low repeat content, diverse basic chromosome numbers and ploidy levels. They also have an interesting phylogeny, short life cycles and simple growth requirements, complemented by a rapidly and continuously growing repertoire of various experimental tools. This presentation outlines and discusses our current projects and their future prospects, using Brachypodium species for research on various aspects of grass genome organisation, e.g. (i) karyotype structure and evolution, (ii) distribution of chromosome territories within the nucleus, (iii) dynamics of epigenetic modifications of chromatin during embryo development and cell differentiation, (iv) true nature of selective silencing of rRNA genes in some Brachypodium allopolyploids and (v) instability of a small grass genome induced via mutagenic treatments.