Conditional promoters to investigate gene function during wheat infection by Zymoseptoria tritici.

Conditional promoters to investigate gene function during wheat infection by Zymoseptoria tritici. Fungal Genet Biol. 2020 Dec 09;:103487 Authors: Fantozzi E, Kilaru S, Cannon S, Schuster M, Gurr SJ, Steinberg G Abstract The fungus Zymoseptoria tritici causes Septoria tritici leaf blotch, which poses a serious threat to temperate-grown wheat. Recently, we described a raft of cell molecular tools to study the biology of this fungus in vitro. Amongst these are 5 conditional promoters (Pnar1, Pex1A, Picl1, Pgal7, PlaraB), which allow controlled over-expression or repression of target genes in cells grown in liquid culture. However, their use in the host-pathogen interaction in planta was not tested. Here, we investigate the behaviour of these promoters by quantitative live cell imaging of green-fluorescent protein-expressing cells during 6 stages of the plant infection process. We show that Pnar1 and Picl1 are repressed in planta and demonstrate their suitability for studying essential gene expression and function in plant colonisation. The promoters Pgal7 and Pex1A are not fully-repressed in planta, but are induced during pycnidiation. This indicates the presence of inducing galactose or xylose and/or arabinose, released from the plant cell wall by the activity of fungal hydrolases. In contrast, the PlaraB promoter, which normally controls expression of an α-l-arabinofuranosidase B, is strongly induced inside the leaf. This suggests t...
Source: Fungal Genetics and Biology - Category: Biology Authors: Tags: Fungal Genet Biol Source Type: research