Comparative Transcriptomic Analysis of Zymoseptoria tritici Reveals Interaction-Specific Gene Expression Patterns...

Area of Science:

• Plant Pathology
• Molecular Plant-Microbe Interactions
• Fungal Genomics

Background:

• Septoria tritici blotch, caused by *Zymoseptoria tritici*, significantly impacts wheat yields.
• Understanding pathogen gene expression during infection is crucial for developing resistant crops.
• Investigating *Z. tritici* interactions with susceptible, resistant, and nonhost plants provides insights into virulence and host specificity.

Purpose of the Study:

• To analyze infection phase-specific gene expression of *Zymoseptoria tritici*.
• To identify candidate effector proteins involved in wheat infection and host immune suppression.
• To compare pathogen gene expression across different plant interactions (susceptible, resistant, nonhost).

Main Methods:

• Gene expression analysis of *Zymoseptoria tritici* at multiple time points post-inoculation (1-23 DPI).
• Comparative transcriptomics between interactions with susceptible wheat, resistant wheat, and nonhost barley.
• Subcellular localization studies of candidate effector proteins using *Agrobacterium*-mediated transient expression in *Nicotiana benthamiana*.

Main Results:

• Dramatic differences in pathogen gene expression observed at 3 and 10 DPI, particularly between host and nonhost interactions.
• Thirty-one putative effectors showed early expression in susceptible hosts compared to nonhosts.
• Two candidate effectors localized to mobile cytosolic bodies, suggesting roles in host signaling or gene regulation.

Conclusions:

• Early-expressed candidate effectors may play a role in suppressing plant immunity.
• Comparative transcriptomics reveals genes involved in host recognition and pathogen colonization.
• This research contributes to understanding the molecular mechanisms underlying *Zymoseptoria tritici* pathogenesis in wheat.