e2101242118.full.pdf (1.92 MB)
Download file

Restoring fertility in yeast hybrids: Breeding and quantitative genetics of beneficial traits

Download (1.92 MB)
journal contribution
posted on 12.10.2021, 12:46 by S Naseeb, F Visinoni, Y Hu, AJ Hinks Roberts, A Maslowska, T Walsh, KA Smart, EJ Louis, D Delneri
Hybrids between species can harbor a combination of beneficial traits from each parent and may exhibit hybrid vigor, more readily adapting to new harsher environments. Interspecies hybrids are also sterile and therefore an evolutionary dead end unless fertility is restored, usually via auto-polyploidisation events. In the Saccharomyces genus, hybrids are readily found in nature and in industrial settings, where they have adapted to severe fermentative conditions. Due to their hybrid sterility, the development of new commercial yeast strains has so far been primarily conducted via selection methods rather than via further breeding. In this study, we overcame infertility by creating tetraploid intermediates of Saccharomyces interspecies hybrids to allow continuous multigenerational breeding. We incorporated nuclear and mitochondrial genetic diversity within each parental species, allowing for quantitative genetic analysis of traits exhibited by the hybrids and for nuclear–mitochondrial interactions to be assessed. Using pooled F12 generation segregants of different hybrids with extreme phenotype distributions, we identified quantitative trait loci (QTLs) for tolerance to high and low temperatures, high sugar concentration, high ethanol concentration, and acetic acid levels. We identified QTLs that are species specific, that are shared between species, as well as hybrid specific, in which the variants do not exhibit phenotypic differences in the original parental species. Moreover, we could distinguish between mitochondria-type–dependent and –independent traits. This study tackles the complexity of the genetic interactions and traits in hybrid species, bringing hybrids into the realm of full genetic analysis of diploid species, and paves the road for the biotechnological exploitation of yeast biodiversity.

Funding

Biotechnology and Biological Sciences Research Council (BBSRC) grant to E.J.L. (BB/L022508/1) and D.D. (BB/L021471/1) in collaboration with SAB-Miller and AB-InBev. F.V. is supported by H2020-MSCA-ITN-2017 grant to D.D. (764364; https://cordis.europa.eu/project/id/764364). A.H.R. has been supported by a BBSRC Collaborative Awards in Science and Engineering studentship to E.J.L. (BB/L017229/1)

History

Citation

PNAS September 21, 2021 118 (38) e2101242118; https://doi.org/10.1073/pnas.2101242118

Author affiliation

Department of Genetics and Genome Biology

Version

VoR (Version of Record)

Published in

Proceedings of the National Academy of Sciences of the United States of America

Volume

118

Issue

38

Pagination

e2101242118

Publisher

Proceedings of the National Academy of Sciences

issn

0027-8424

eissn

1091-6490

Copyright date

2021

Available date

12/10/2021

Language

en

Usage metrics

Categories

Exports