Live Imaging Characterization of Centromere Movements During Male Meiotic Prophase in Arabidopsis thaliana

Meiosis is a cellular division, essential for sexual reproduction. During meiotic prophase, homologous chromosomes of maternal and paternal origin recognize each other and associate, a process that is facilitated by their rapid movements in the nucleoplasm. Meiotic prophase movements rely on the attachment of the chromosomes to the nuclear envelope and on cytoplasmic forces transmitted to the chromosomes through the nuclear envelope. In plants, the limited accessibility and fragility of male meiocytes inside the anthers make live imaging approaches and chromosome movement analysis technically challenging. Indeed, these movements are very rapid, and analyzing them requires finding the optimal acquisition conditions. Here, an efficient method to capture rapid chromosome movements during male meiotic prophase in Arabidopsis thaliana is described, in time-lapse movies, by following the movements of fluorescent-tagged centromeres. It is based on anther dissection and image acquisition using confocal laser scanning microscopy (CLSM), in 3D and over time. Acquiring meiotic z-stacks every 7 s allows sufficient resolution to reconstruct and analyze the trajectories of tagged centromeres. The extracted data is subsequently processed, enabling the quantitative analysis of these chromosomal movements. The development of models from this data is essential for understanding the mechanism of rapid chromosome movement, including the nature and intensity of the forces driving this process.