Active transcription and Orc1 drive chromatin association of the AAA+ ATPase Pch2 during meiotic G2/prophase

PLoS Genet. 2020 Jun 22;16(6):e1008905. doi: 10.1371/journal.pgen.1008905. eCollection 2020 Jun.

Abstract

Pch2 is an AAA+ protein that controls DNA break formation, recombination and checkpoint signaling during meiotic G2/prophase. Chromosomal association of Pch2 is linked to these processes, and several factors influence the association of Pch2 to euchromatin and the specialized chromatin of the ribosomal (r)DNA array of budding yeast. Here, we describe a comprehensive mapping of Pch2 localization across the budding yeast genome during meiotic G2/prophase. Within non-rDNA chromatin, Pch2 associates with a subset of actively RNA Polymerase II (RNAPII)-dependent transcribed genes. Chromatin immunoprecipitation (ChIP)- and microscopy-based analysis reveals that active transcription is required for chromosomal recruitment of Pch2. Similar to what was previously established for association of Pch2 with rDNA chromatin, we find that Orc1, a component of the Origin Recognition Complex (ORC), is required for the association of Pch2 to these euchromatic, transcribed regions, revealing a broad connection between chromosomal association of Pch2 and Orc1/ORC function. Ectopic mitotic expression is insufficient to drive recruitment of Pch2, despite the presence of active transcription and Orc1/ORC in mitotic cells. This suggests meiosis-specific 'licensing' of Pch2 recruitment to sites of transcription, and accordingly, we find that the synaptonemal complex (SC) component Zip1 is required for the recruitment of Pch2 to transcription-associated binding regions. Interestingly, Pch2 binding patterns are distinct from meiotic axis enrichment sites (as defined by Red1, Hop1, and Rec8). Inactivating RNAPII-dependent transcription/Orc1 does not lead to effects on the chromosomal abundance of Hop1, a known chromosomal client of Pch2, suggesting a complex relationship between SC formation, Pch2 recruitment and Hop1 chromosomal association. We thus report characteristics and dependencies for Pch2 recruitment to meiotic chromosomes, and reveal an unexpected link between Pch2, SC formation, chromatin and active transcription.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromatin / metabolism
  • Chromatin Immunoprecipitation Sequencing
  • Chromosomes, Fungal / metabolism
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • G2 Phase / genetics
  • Mutation
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Origin Recognition Complex / genetics
  • Origin Recognition Complex / metabolism*
  • RNA Polymerase II / metabolism
  • RNA-Seq
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Synaptonemal Complex / genetics
  • Synaptonemal Complex / metabolism*
  • Transcription, Genetic*

Substances

  • Chromatin
  • DNA-Binding Proteins
  • HOP1 protein, S cerevisiae
  • Nuclear Proteins
  • ORC1 protein, S cerevisiae
  • Origin Recognition Complex
  • Pch2 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Zip1 protein, S cerevisiae
  • RNA Polymerase II

Grants and funding

GV was funded by the European Research Council (ERC Starting Grant URDNA, agreement nr. 638197, www.erc.europa.eu). RCS was funded by the CAPES-Humboldt fellowship from the Alexander von Humboldt Foundation (agreement nr. 99999.000021/2016-04, www.humboldt-foundation.de). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.