Uniparental nuclear inheritance following bisexual mating in fungi
Abstract
Some remarkable animal species require an opposite-sex partner for their sexual development but discard the partner’s genome before gamete formation, generating hemi-clonal progeny in a process called hybridogenesis. Here, we discovered a similar phenomenon, termed pseudosexual reproduction, in a basidiomycete human fungal pathogen, Cryptococcus neoformans, where exclusive uniparental inheritance of nuclear genetic material was observed during bisexual reproduction. Analysis of strains expressing fluorescent reporter proteins revealed instances where only one of the parental nuclei was present in the terminal sporulating basidium. Whole-genome sequencing revealed the nuclear genome of the progeny was identical with one or the other parental genome. Pseudosexual reproduction was also detected in natural isolate crosses where it resulted in mainly MATa progeny, a bias observed in Cryptococcus ecological distribution as well. The mitochondria in these progeny were inherited from the MAT<strong>a</strong> parent, resulting in nuclear-mitochondrial genome exchange. The meiotic recombinase Dmc1 was found to be critical for pseudosexual reproduction. These findings reveal a novel, and potentially ecologically significant, mode of eukaryotic microbial reproduction that shares features with hybridogenesis in animals.
Data availability
The sequence data generated in this study were submitted to NCBI with the BioProject accession number PRJNA682203.
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Illumina reads of VYD135SRA database, SRR10317030.
Article and author information
Author details
Funding
National Institute of Allergy and Infectious Diseases (AI39115-24)
- Joseph Heitman
National Institute of Allergy and Infectious Diseases (AI50113-16)
- Joseph Heitman
National Institute of Allergy and Infectious Diseases (AI33654-04)
- Joseph Heitman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Luis F Larrondo, Pontificia Universidad Católica de Chile, Chile
Version history
- Preprint posted: December 3, 2020 (view preprint)
- Received: January 4, 2021
- Accepted: July 27, 2021
- Accepted Manuscript published: August 2, 2021 (version 1)
- Version of Record published: September 2, 2021 (version 2)
Copyright
© 2021, Yadav 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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