Genome-Informed Trophic Classification and Functional Characterization of Virulence Proteins from the Maize Tar Spot Pathogen Phyllachora maydis .
Abigail RogersNamrata JaiswalEmily RoggenkampHye-Seon KimJoshua S MacCreadyMartin I ChilversSteven R ScofieldAnjali S Iyer-PascuzziMatthew HelmPublished in: Phytopathology (2024)
Phyllachora maydis is an ascomycete foliar fungal pathogen and the causal agent of tar spot in maize. Although P. maydis is considered an economically important foliar pathogen of maize, our general knowledge of the trophic lifestyle and functional role of effector proteins from this fungal pathogen remains limited. Here, we utilized a genome-informed approach to predict the trophic lifestyle of P. maydis and functionally characterized a subset of candidate effectors from this fungal pathogen. Leveraging the most recent P. maydis genome annotation and the CATAStrophy pipeline, we show that this fungal pathogen encodes a predicted carbohydrate-active enzymes (CAZymes) repertoire consistent with that of biotrophs. To investigate fungal pathogenicity, we selected 18 candidate effector proteins that were previously shown to be expressed during primary disease development. We assessed whether these putative effectors share predicted structural similarity with other characterized fungal effectors and determined whether any suppress plant immune responses. Using AlphaFold2 and Foldseek, we showed that one candidate effector, PM02_g1115, adopts a predicted protein structure similar to that of an effector from Verticillium dahlia . Furthermore, transient expression of candidate effector-fluorescent protein fusions in Nicotiana benthamiana revealed two putative effectors, PM02_g378 and PM02_g2610, accumulated predominantly in the cytosol, and three candidate effectors, PM02_g1115, PM02_g7882, and PM02_g8240, consistently attenuated chitin-mediated reactive oxygen species production. Collectively, the results presented herein provide insights into the predicted trophic lifestyle and putative functions of effectors from P. maydis and will likely stimulate continued research to elucidate the molecular mechanisms used by P. maydis to induce tar spot.
Keyphrases
- type iii
- particulate matter
- air pollution
- polycyclic aromatic hydrocarbons
- candida albicans
- heavy metals
- regulatory t cells
- dendritic cells
- cell wall
- immune response
- metabolic syndrome
- water soluble
- cardiovascular disease
- reactive oxygen species
- physical activity
- biofilm formation
- healthcare
- weight loss
- machine learning
- pseudomonas aeruginosa
- genome wide
- deep learning
- staphylococcus aureus
- poor prognosis
- binding protein
- brain injury
- protein protein
- dna methylation
- gene expression
- quantum dots
- toll like receptor
- cerebral ischemia
- subarachnoid hemorrhage
- cystic fibrosis
- label free