PLoS ONE (Jan 2022)

Arrested crossover precursor structures form stable homologous bonds in a Tetrahymena meiotic mutant.

  • Miao Tian,
  • Kazufumi Mochizuki,
  • Josef Loidl

DOI
https://doi.org/10.1371/journal.pone.0263691
Journal volume & issue
Vol. 17, no. 2
p. e0263691

Abstract

Read online

Meiotic DNA double-strand breaks produce reciprocally exchanged DNA strands, which mature into chiasmata that hold homologous chromosomes together as bivalents. These bivalents are subsequently separated in the first meiotic division. In a mutant lacking the newly identified Tetrahymena gene APRO1 (Anaphase promoting 1), meiosis is arrested by the end of prophase. Mature chiasmata are not formed but bivalents are connected via a molecular precursor structure. In-depth analysis of this arrested intermediate structure may help to elucidate the noncanonical molecular recombination pathway in Tetrahymena.