RT Journal Article
SR Electronic
T1 The <em>Parastagonospora nodorum</em> necrotrophic effector SnTox5 targets the wheat gene <em>Snn5</em> and facilitates entry into the leaf mesophyll
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.02.26.433117
DO 10.1101/2021.02.26.433117
A1 Gayan K. Kariyawasam
A1 Jonathan K. Richards
A1 Nathan A. Wyatt
A1 Katherine Running
A1 Steven S. Xu
A1 Zhaohui Liu
A1 Pawel Borowicz
A1 Justin D. Faris
A1 Timothy L. Friesen
YR 2021
UL http://biorxiv.org/content/early/2021/02/28/2021.02.26.433117.abstract
AB Parastagonospora nodorum, causal agent of septoria nodorum blotch, is a destructive necrotrophic fungal pathogen of wheat. P. nodorum is known to secrete several necrotrophic effectors that target wheat susceptibility genes that trigger classical biotrophic resistance responses but resulting in susceptibility rather than resistance. SnTox5 targets the wheat susceptibility gene Snn5 to induce necrosis. In this study, we used full genome sequences of 197 P. nodorum isolates collected from the US and their disease phenotyping on the Snn5 differential line LP29, to perform genome wide association study analysis to localize the SnTox5 gene to chromosome 8 of P. nodorum. SnTox5 was validated using gene transformation and CRISPR-Cas9 based gene disruption. SnTox5 encoded a small secreted protein with a 22 and 45 amino acid secretion signal and a pro sequence, respectively. The SnTox5 gene is under purifying selection in the Upper Midwest but under strong diversifying selection in the South/East regions of the US. Comparison of wild type and SnTox5-disrupted strains on wheat lines with and without the susceptibility target Snn5 showed that SnTox5 has two functions, 1) facilitating colonization of the mesophyll layer, and 2) targeting Snn5 to induce programmed cell death to provide cellular nutrient to complete its necrotrophic life cycle.Competing Interest StatementThe authors have declared no competing interest.