Comparative Genomics and Transcriptomics To Analyze Fruiting Body Development in Filamentous Ascomycetes

Area of Science:

• Mycology
• Genomics
• Molecular Biology

Background:

• Filamentous ascomycetes form complex three-dimensional fruiting bodies for sexual spore production and dispersal.
• The molecular mechanisms governing fruiting body development are not fully understood.
• Comparative transcriptomics suggests a conserved set of genes may be involved across species.

Purpose of the Study:

• To investigate the genetic basis of fruiting body development in filamentous ascomycetes.
• To identify conserved, upregulated genes during fruiting body formation across different species.
• To perform functional analysis of candidate genes involved in this complex developmental process.

Main Methods:

• Genome sequencing of the Pezizomycete *Ascodesmis nigricans*, yielding the smallest Pezizomycete genome to date (27 Mb).
• Comparative transcriptomics analysis of developing fruiting bodies from *Ascodesmis nigricans*, *Pyronema confluens*, and *Sordaria macrospora*.
• Identification of commonly upregulated genes during fruiting body development and subsequent functional analysis via gene deletion in *S. macrospora*.

Main Results:

• Gene expression patterns during fruiting body development were more similar across the three species than to their nonsexual hyphae.
• 83 genes were consistently upregulated during fruiting body development across all three species.
• Functional analysis confirmed three of four tested genes are involved in fruiting body formation, including two chromatin modifier genes.

Conclusions:

• Conserved gene expression patterns highlight a core genetic program for fruiting body development in filamentous ascomycetes.
• Genes involved in vesicle transport, endomembrane system function, and chromatin organization are critical for this process.
• This study provides valuable insights into the molecular mechanisms of fungal sexual reproduction and identifies key targets for future research.