Centre for Gene Regulation and Expression, Sir James Black Centre, School of Life Sciences, University of Dundee, Dundee, United Kingdom
Jacqueline Budrewicz
Ludwig Institute for Cancer Research, San Diego, United States; Department of Cellular and Molecular Medicine, University of California, San Diego, San Diego, United States
Pablo Lara-Gonzalez
Ludwig Institute for Cancer Research, San Diego, United States; Department of Cellular and Molecular Medicine, University of California, San Diego, San Diego, United States
Christopher G Sorensen Turpin
Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, United States
Joshua N Bembenek
Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, United States
Dhanya K Cheerambathur
Wellcome Centre for Cell Biology & Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh, United Kingdom
Protein Phosphatase 2A (PP2A) is a heterotrimer composed of scaffolding (A), catalytic (C), and regulatory (B) subunits. PP2A complexes with B56 subunits are targeted by Shugoshin and BUBR1 to protect centromeric cohesion and stabilise kinetochore–microtubule attachments in yeast and mouse meiosis. In Caenorhabditis elegans, the closest BUBR1 orthologue lacks the B56-interaction domain and Shugoshin is not required for meiotic segregation. Therefore, the role of PP2A in C. elegans female meiosis is unknown. We report that PP2A is essential for meiotic spindle assembly and chromosome dynamics during C. elegans female meiosis. BUB-1 is the main chromosome-targeting factor for B56 subunits during prometaphase I. BUB-1 recruits PP2A:B56 to the chromosomes via a newly identified LxxIxE motif in a phosphorylation-dependent manner, and this recruitment is important for proper chromosome congression. Our results highlight a novel mechanism for B56 recruitment, essential for recruiting a pool of PP2A involved in chromosome congression during meiosis I.
