A 'parameiosis' drives depolyploidization and homologous recombination in Candida albicans

Nat Commun. 2019 Sep 26;10(1):4388. doi: 10.1038/s41467-019-12376-2.

Abstract

Meiosis is a conserved tenet of sexual reproduction in eukaryotes, yet this program is seemingly absent from many extant species. In the human fungal pathogen Candida albicans, mating of diploid cells generates tetraploid products that return to the diploid state via a non-meiotic process of depolyploidization known as concerted chromosome loss (CCL). Here, we report that recombination rates are more than three orders of magnitude higher during CCL than during normal mitotic growth. Furthermore, two conserved 'meiosis-specific' factors play central roles in CCL as SPO11 mediates DNA double-strand break formation while both SPO11 and REC8 regulate chromosome stability and promote inter-homolog recombination. Unexpectedly, SPO11 also promotes DNA repair and recombination during normal mitotic divisions. These results indicate that C. albicans CCL represents a 'parameiosis' that blurs the conventional boundaries between mitosis and meiosis. They also reveal parallels with depolyploidization in mammalian cells and provide potential insights into the evolution of meiosis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Candida albicans / genetics*
  • Candidiasis / microbiology
  • Chromosomes, Fungal / genetics
  • DNA Damage
  • Diploidy*
  • Endodeoxyribonucleases / genetics
  • Endodeoxyribonucleases / metabolism
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism
  • Homologous Recombination / genetics*
  • Humans
  • Meiosis / genetics*
  • Mitosis / genetics
  • Rec A Recombinases / genetics
  • Rec A Recombinases / metabolism
  • Recombinational DNA Repair
  • Tetraploidy*

Substances

  • Fungal Proteins
  • Rec A Recombinases
  • Endodeoxyribonucleases
  • meiotic recombination protein SPO11