Comparative proteomics and phosphoproteomics to decipher signal transduction in Botrytis cinerea.

Jaafar Kilani (1) , Marlène Davanture (2) , Michel Zivy (2, 3) , Sabine Fillinger (1)

1 BIOGER - BIOlogie et GEstion des Risques en agriculture
2 GQE-Le Moulon - Génétique Quantitative et Evolution - Le Moulon (Génétique Végétale)
3 PAPPSO - Plateforme d'Analyse Protéomique de Paris Sud Ouest

Adaptation to changing environmental conditions takes place rapidly in all living organisms: cells must respond to a wide variety of signals. Through successive protein phosphorylation and de-phosphorylation steps, signal transduction cascades mediate between the perception of the extracellular conditions and the adaptation of intracellular processes. Botrytis cinerea is a necrotrophic, polyphageous plant pathogen, that causes gray mold disease and can infect over 1000 plant species including several agronomically important crops (grapevine, strawberry, tomatoes …). Fungicides remain the most effective means to combat this disease. However B. cinerea rapidly adapts to fungicides. Presently, the phenylpyrrole fludioxonil is one of the most efficient fungicides against B. cinerea. Therefore deciphering the response to fludioxonil in B. cinerea is crucial. In Botrytis cinerea, the fungicide fludioxonil activates the Sak1 (Hog1-like) and Bmp3 (Slt2-like) MAPKs, which are respectively involved in osmoregulation, cell wall integrity, development and pathogenicity. In order to trace the transduction of fludioxonil to the MAPK pathways, we have undertaken a comparative proteomics and phosphoproteomics study of the B. cinerea osmosensing pathway challenged by the fungicide fludioxonil. We compared mutants of the sensor histidine-kinase Bos1 and of the MAPK Sak1 to the parental wild-type. Strains were exposed (or not) to fludioxonil for 15 min during exponential in vitro growth. Shotgun proteomics revealed considerable differences in protein content among the strains, but no treatment effect. These results indicate a strong transcriptional and/or translational regulation under Bos1 and Sak1 control, respectively, under standard conditions. One of the most relevant result is the abundance of 263 proteins controlled by Bos1 and Sak1 independently. Proteins of the oxidative stress response are under negative control of Bos1, while some proteases are positively regulated. In addition, proteins involved in translation are specifically regulated by Bos1. It appears that Bos1 is important in different biological processes. Sak1, on its turn, controls the abundance of proteins involved in oxidative stress response, early secretome, protein folding, primary metabolism and secondary metabolism. Quantitative phosphoproteomics is ongoing and it will permit to verify a clear response to the fludioxonil treatment as well as (de)phosphorylation events controlled independently by Bos1 or Sak1, or by both kinases

Mots clés: polyphageous plant pathogen; fungicides; Botrytis cinerea

Domaines: Sciences du Vivant [q-bio]

Jaafar Kilani, Marlène Davanture, Michel Zivy, Sabine Fillinger. Comparative proteomics and phosphoproteomics to decipher signal transduction in Botrytis cinerea.. 29. Fungal genetics conference Asilomar 17, Mar 2017, Pacific Grove CA, United States. p.212. ⟨hal-01604794⟩