Analysis of meiosis in Pristionchus pacificus reveals plasticity in homolog pairing and synapsis in the nematode lineage
Regina Rillo-Bohn,
Renzo Adilardi,
Therese Mitros,
Barış Avşaroğlu,
Lewis Stevens,
Simone Köhler,
Joshua Bayes,
Clara Wang,
Sabrina Lin,
K Alienor Baskevitch,
Daniel S Rokhsar,
Abby F Dernburg
Affiliations
Regina Rillo-Bohn
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States; Howard Hughes Medical Institute, Chevy Chase, United States
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States; Howard Hughes Medical Institute, Chevy Chase, United States
Therese Mitros
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
Barış Avşaroğlu
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States; Howard Hughes Medical Institute, Chevy Chase, United States
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States; Darwin Tree of Life Project, Wellcome Sanger Institute, Cambridge, United Kingdom
Simone Köhler
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States; Howard Hughes Medical Institute, Chevy Chase, United States
Joshua Bayes
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
Clara Wang
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States; Howard Hughes Medical Institute, Chevy Chase, United States
Sabrina Lin
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States; Howard Hughes Medical Institute, Chevy Chase, United States
K Alienor Baskevitch
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States; Howard Hughes Medical Institute, Chevy Chase, United States
Daniel S Rokhsar
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States; Department of Energy Joint Genome Institute, Berkeley, United States; Okinawa Institute of Science and Technology Graduate University, Onna, Japan; Chan Zuckerberg Biohub, San Francisco, United States
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States; Howard Hughes Medical Institute, Chevy Chase, United States; Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, United States; California Institute for Quantitative Biosciences, Berkeley, United States
Meiosis is conserved across eukaryotes yet varies in the details of its execution. Here we describe a new comparative model system for molecular analysis of meiosis, the nematode Pristionchus pacificus, a distant relative of the widely studied model organism Caenorhabditis elegans. P. pacificus shares many anatomical and other features that facilitate analysis of meiosis in C. elegans. However, while C. elegans has lost the meiosis-specific recombinase Dmc1 and evolved a recombination-independent mechanism to synapse its chromosomes, P. pacificus expresses both DMC-1 and RAD-51. We find that SPO-11 and DMC-1 are required for stable homolog pairing, synapsis, and crossover formation, while RAD-51 is dispensable for these key meiotic processes. RAD-51 and DMC-1 localize sequentially to chromosomes during meiotic prophase and show nonoverlapping functions. We also present a new genetic map for P. pacificus that reveals a crossover landscape very similar to that of C. elegans, despite marked divergence in the regulation of synapsis and crossing-over between these lineages.