BAF-1-VRK-1 mediated release of meiotic chromosomes from the nuclear periphery is important for genome integrity.

Abstract

Rapid prophase chromosome movements ensure faithful alignment of the parental homologous chromosomes and successful synapsis formation during meiosis. These movements are driven by cytoplasmic forces transmitted to the nuclear periphery, where chromosome ends are attached through transmembrane proteins. During many developmental stages a specific genome architecture with chromatin nuclear periphery contacts mediates specific gene expression. Whether chromatin is removed from the nuclear periphery as a consequence of chromosome motions or by a specific mechanism is not fully understood. Here, we identify a mechanism to remove chromatin from the nuclear periphery through vaccinia related kinase (VRK-1)-dependent phosphorylation of Barrier to Autointegration Factor 1 (BAF-1) in Caenorhabditis elegans early prophase of meiosis. Interfering with chromatin removal delays chromosome pairing, impairs synapsis, produces oocytes with abnormal chromosomes and elevated apoptosis. Long read sequencing reveals deletions and duplications in offspring lacking VRK-1 underscoring the importance of the BAF-1-VRK-1 module in preserving genome stability in gametes during rapid chromosome movements.