Meiotic drive of female-inherited supernumerary chromosomes in a pathogenic fungus
Abstract
Meiosis is a key cellular process of sexual reproduction involving the pairing of homologous sequences. In many species however, meiosis can also involve the segregation of supernumerary chromosomes, which can lack a homolog. How these unpaired chromosomes undergo meiosis is largely unknown. In this study we investigated chromosome segregation during meiosis in the haploid fungus Zymoseptoria tritici that possesses a large complement of supernumerary chromosomes. We used isogenic whole chromosome deletion strains to compare meiotic transmission of chromosomes when paired and unpaired. Unpaired chromosomes inherited from the male parent as well as paired supernumerary chromosomes in general showed Mendelian inheritance. In contrast, unpaired chromosomes inherited from the female parent showed non-Mendelian inheritance but were amplified and transmitted to all meiotic products. We concluded that the supernumerary chromosomes of Z. tritici show a meiotic drive and propose an additional feedback mechanism during meiosis which initiates amplification of unpaired female-inherited chromosomes.
Data availability
Sequencing reads have been deposited in the Sequence Read Archive and are available under the BioProject PRJNA438050. These datasets will be made public upon acceptance of manuscript. All data generated or analysed during this study are included in the manuscript and supporting files (Supplementary Files 2-4). Source data files have been provided for Figures 2 and Figure 2—figure supplement 1.
Article and author information
Author details
Funding
State of Schleswig Holstein
- Eva Holtgrewe Stukenbrock
Max-Planck-Gesellschaft (Open-access funding)
- Eva Holtgrewe Stukenbrock
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Habig 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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