Aggregation adaptive routes revealed by transcriptomic and ultrastructural signatures in Phytophthora parasitica

ABSTRACT: Within oomycetes, Phytophthora is a genus of eukaryotic microorganisms encompassing some of the most damaging plant pathogens. It spreads by airborne sporangia or waterborne zoospores. Zoospores perceive plant signals through chemotaxis and electrotaxis, and produce signals to attract other zoospores (autotaxis), resulting in auto-aggregation or biofilm formation on the plant surface. The mechanisms underlying intercellular communication and consequent attraction, adhesion and aggregation are largely unknown. Recent studies demonstrated that in Phytophthora parasitica the perception of K+ gradient induced coordinated motion and rapid aggregation. Based on this model, we combined data mining and ultrastructural microscopy analyses to propose a first definition of molecular events leading to oomycete aggregation. Results indicate that the transcriptome repertoire required for aggregation is fully functional already at this single zoospore stage, before aggregation or encystment. Freely swimming zoospores secrete or harbor proteins implied in aggregation through adhesion and extracellular matrix elaboration. They secrete vesicular and fibrillary material, including fibronectin-like proteins, resulting in intercellular structure formation. Consistently, the signature of transcriptome dynamics during transition from single-cell to aggregate is an upregulation of genes contributing to vesicular trafficking, possibly involved in adhesive proteins and extracellular matrix components mobilization. Moreover, the transcriptome signature suggests that pH homeostasis may contribute to aggregation by acting on both zoospore movement and adhesion.

ORGANISM(S): Phytophthora nicotianae

PROVIDER: GSE142435 | GEO | 2020/08/12

REPOSITORIES: GEO