Allelic diversity of the Zymoseptoria tritici effector Zt-11 leads to the loss of interactions with small, secreted proteins from wheat
Year: 2025
Type: article
Abstract: Pathogen secreted effector proteins play a key role in host-pathogen interactions, however the evolutionary and structural mechanisms underlying their diversification remain poorly understood. Previously, Zt-11 was found to interact with small, secreted proteins from wheat and deletion of Zt-11 delayed Septoria tritici blotch (STB) disease development in wheat. Here, we investigate the diversity of Zt-11 a Zymoseptoria tritici pathogen effector. Examination of 168 field isolates revealed high allelic diversity in Zt-11 with three distinct Zt-11 isoform groups and signatures of positive selection. Structural predictions of these isoforms and the wheat host interacting protein TaSRTRG6, exhibit high structural confidence (pLDDT >80). Whereas the wheat interactors TaSSP6 and TaSSP7 are intrinsically disordered proteins with no reliable structural model. Molecular docking and yeast two-hybrid assays revealed haplotype-specific binding between Zt-11 and TaSRTRG6, with some isoforms showing loss of interaction in vivo. Finally, the I1:H1 haplotype which no longer interacts with the small, secreted wheat proteins (TaSRTRG6, TaSSP6 and TaSSP7) also displayed increased disease symptoms during wheat infection assays. Together these findings suggest that Zt-11 undergoes evolution through positive selection and structural adaptation enabling evasion from host small, secreted proteins.
Source: Plant Stress
Authors: Sujit Jung Karki, Debabrata Dutta, Eoghan Curran, Paola Pilo, Nikolaos Mastrodimos, James Burke, Binbin Zhou, Saoirse Tracy, Fiona Doohan, Angela Feechan
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: gold
Estimated APC paid: $2,310
OpenAlex ID: W7107875313