Cene Gostinčar (Author), Sun Xiaohuan (Author), Anja Černoša (Author), Fang Chao (Author), Nina Gunde-Cimerman (Author), Song Zewei (Author)

Abstract

Background: The great diversity of lifestyles and survival strategies observed in fungi is reflected in the many ways in which they reproduce and recombine. Although a complete absence of recombination is rare, it has been reported for some species, among them 2 extremotolerant black yeasts from Dothideomycetes: Hortaea werneckii and Aureobasidium melanogenum. Therefore, the presence of diploid strains in these species cannot be explained as the product of conventional sexual reproduction. Results: Genome sequencing revealed that the ratio of diploid to haploid strains in both H. werneckii and A. melanogenum is about 2:1. Linkage disequilibrium between pairs of polymorphic loci and a high degree of concordance between the phylogenies of different genomic regions confirmed that both species are clonal. Heterozygosity of diploid strains is high, with several hybridizing genome pairs reaching the intergenomic distances typically seen between different fungal species. The origin of diploid strains collected worldwide can be traced to a handful of hybridization events that produced diploids, which were stable over long periods of time and distributed over large geographic areas. Conclusions: Our results, based on the genomes of over 100 strains of 2 black yeasts, show that although they are clonal, they occasionally form stable and highly heterozygous diploid intraspecific hybrids. The mechanism of these apparently rare hybridization events, which are not followed by meiosis or haploidization, remains unknown. Both extremotolerant yeasts, H. werneckii and even more so A. melanogenum, a close relative of the intensely recombining and biotechnologically relevant Aureobasidium pullulans, provide an attractive model for studying the role of clonality and ploidy in extremotolerant fungi.

Keywords

populacijska genomika;halotoleranca;ekstremotoleranca;halofilne glive;Hortaea werneckii;Aureobasidium melanogenum;hibridizacija;population genomics;halotolerance;extremotolerance;halophilic fungus;hybridization;

Data

Language: English
Year of publishing:
Typology: 1.01 - Original Scientific Article
Organization: UL BF - Biotechnical Faculty
UDC: 575.111
COBISS: 126622211 Link will open in a new window
ISSN: 2047-217X
Views: 16
Downloads: 4
Average score: 0 (0 votes)
Metadata: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Other data

Secondary language: Slovenian
Secondary keywords: populacijska genomika;halotoleranca;ekstremotoleranca;halofilne glive;Hortaea werneckii;Aureobasidium melanogenum;hibridizacija;
Type (COBISS): Article
Pages: str. [1]-16
Issue: ǂVol. ǂ11
Chronology: Oct. 2022
DOI: 10.1093/gigascience/giac095
ID: 19845542