RELATIONSHIP BETWEEN PII PROTEIN AND ENVIRONMENTAL STRESSES IN ARABIDOPSIS

AZNAR N; MARTÍNEZ NOËL G; SALERNO G; CONSOLO F

Congreso; LII SAIB; 2016

PII proteins are central regulators of nitrogen (N) metabolism in eubacteria and cyanobacteria. They also coordinate the relationship between N and carbon metabolism and sense cell energy status. In eukaryotes, PII homologs have been only reported in red algae and plants. Plant PII is targeted to plastids and is encoded by a nuclear gene (GLB1). The Arabidopsis PII mutant is viable and has not severe phenotype. Since its identification in photosynthetic eukaryotes, many efforts have been made to unravel its biological function. To gain insights in the PII protein role in plants, we submitted an Arabidopsis mutant lacking PII to different abiotic (salt and oxidative) and biotic (infection with the fungal pathogen Fusarium graminearum) stresses. Different phenotypic and biochemical analysis were performed. Our results showed that even though PII is not essential, the lack of that protein caused modifications in the plant response to abiotic and biotic stresses. One of the most relevant effects was the increased tolerance to Fusarium infection exhibited by the PII mutant. We also analyzed the PII transcript levels under control and stress conditions in Arabidopsis wild-type by RT-PCR experiments. In conclusion, our data indicate that PII protein could have a role in the response to environmental stresses in Arabidopsis. Supported by CONICET, ANPCyT, UNMdP and FIBA.