BUB-1 targets PP2A:B56 to regulate chromosome congression during meiosis I in C. elegans oocytes
- University of Dundee, United Kingdom
- Ludwig Institute for Cancer Research, United States
- University of Tennessee, United States
- University of Michigan, United States
- University of Edinburgh, United Kingdom
Abstract
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 C. elegans the closest BUBR1 ortholog 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.
Data availability
While some time points are shown in the figures, representative movies showing all time points are provided as Supplementary Movies. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE (Perez-Riverol et al., 2019) partner repository with the dataset identifier PXD023258.
Article and author information
Author details
Conchita Fraguas Bringas
Funding
Medical Research Council (MR/R008574/1)
- Laura Bel Borja
- Flavie Soubigou
- Federico Pelisch
The Wellcome (208833)
- Dhanya K Cheerambathur
NIH Office of the Director (R01 GM074215)
- Jacqueline Budrewicz
- Pablo Lara-Gonzalez
NIH Office of the Director (R01 GM114471)
- Christopher G Sorensen Turpin
- Joshua N Bembenek
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Bel Borja et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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BUB-1 targets PP2A:B56 to regulate chromosome congression during meiosis I in C. elegans oocytes
eLife 9:e65307.
https://doi.org/10.7554/eLife.65307
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