Polymer dynamics reveal stage-wise unfolding and homologous pairing of chromosomes in S. pombe

Abstract

During meiosis, the exchange of genetic material ("recombination") is essential to bring up the genetic variation in offspring. To carry out the recombination, homologous pairs of DNA have to come in proximity and align. In fission yeast, this is accomplished by the extensive nuclear oscillation that applies pulling force on the chromosomes. In this work, we investigate the competition between the pulling force that tries to facilitate the alignment and the intra-chromatin interactions that assist the chromatin folding. The crucial role played by the intra-chromatin interaction for a range of pulling forces and loci location is highlighted here. Upon comparing our results with the experimental findings, we not only reaffirm the enhancement of contact probability with loci-dependent pulling but also get a meaningful interpretation of the chromosome unfolding and pairing in different stages of movement.