Are Fungal Disease Outbreaks Instigated by Starship Transposons?

Area of Science:

• Mycology
• Plant Pathology
• Genetics

Background:

• Fungal diseases pose a significant threat to global agriculture.
• Horizontal gene transfer (HGT) is a known mechanism for generating novel fungal pathogens.
• The mediators of HGT in fungi remain largely unknown.

Purpose of the Study:

• To investigate the potential role of Starships, a superfamily of giant transposable elements, in mediating HGT of genes between fungal species.
• To explore the involvement of Starships in fungal disease outbreaks and pathogen evolution.

Main Methods:

• Review of existing literature and data on fungal pathogens and transposable elements.
• Analysis of three case studies: ToxA in wheat pathogens, Glomerella leaf spot in apple trees, and Verticillium dahliae in cotton.
• Comparative analysis of Starship elements in distantly related fungal species.

Main Results:

• Three potential cases are presented where Starships may have mediated disease outbreaks.
• Strong evidence is provided for a Starship-mediated mechanism in Verticillium dahliae, with disease-promoting genes found on related Starships across species.
• The findings suggest Starships can facilitate the transfer of virulence factors.

Conclusions:

• Starships are proposed as a significant mechanism for mediating horizontal gene transfer in fungal pathogens.
• Understanding Starship-mediated gene transfer can inform novel strategies for managing agricultural fungal diseases.
• Further research into Starships' role in fungal evolution is warranted.