MYCOLab Ai Logo - gold and army green

An Overview of the Function and Maintenance of Sexual Reproduction in Dikaryotic Fungi

Summary

This research examines how fungi reproduce sexually and why different species have evolved different reproductive strategies. Sexual reproduction in fungi appears to have evolved primarily as a way to repair DNA damage, with increased genetic diversity being a secondary benefit. The study reveals how different fungal lifestyles – whether living on dead matter or causing disease in plants or humans – have shaped their reproductive strategies. Impacts on everyday life: – Helps explain how fungal plant diseases spread and evolve, affecting agriculture and food security – Provides insights into how human fungal infections develop and persist – Advances our understanding of basic biological processes shared across many organisms – Contributes to developing better antifungal treatments and crop protection strategies – Demonstrates how organisms adapt their reproduction based on their environment

Background

Sexual reproduction likely evolved as a mechanism to repair DNA damage and protect from environmental stresses, particularly through homologous recombination during meiosis. In higher eukaryotes, meiosis and gamete production provides increased genetic variation. However, in fungi, while meiosis remains important, outcrossing appears less critical. The Dikarya subkingdom is characterized by extended dikaryotic life cycle stages and possess functional or relictual mating loci that govern sexual reproduction between members of their species.

Objective

This review explores, compares and contrasts different sexual reproduction strategies used among the Dikarya fungi, examining both saprophytic and pathogenic species. It aims to highlight key differences between mammalian and plant pathogens to provide context for selective pressures acting on this fungal group. The review analyzes how mating systems and sexual reproduction have evolved differently based on lifestyle and host interactions.

Results

The review found that while all examined fungi possess mating type loci components, their utilization varies greatly. Saprophytic species mate infrequently but maintain mating ability for DNA repair. Plant pathogenic basidiomycetes require mating for host infection, while ascomycete plant pathogens often avoid mating. Human fungal pathogens generally minimize sexual reproduction to avoid immune responses. Mating systems range from simple bipolar to complex tetrapolar arrangements with thousands of mating types.

Conclusion

The maintenance of mating type loci across dikaryotic fungi suggests an important fitness advantage, likely related to DNA damage repair through meiotic recombination. However, the frequency and role of sexual reproduction has evolved differently based on lifestyle and host interactions. Plant pathogens often require mating for infection, while human pathogens minimize mating to avoid immune responses. This demonstrates how ecological niches have shaped the evolution of fungal mating systems while maintaining core mating type components.
  • Published in:Frontiers in Microbiology,
  • Study Type:Review,
  • Source: 10.3389/fmicb.2018.00503
Scroll to Top