Trehalose and (iso)floridoside production under desiccation stress in red alga Porphyra umbilicalis and the genes involved in their synthesis

Yuanyu Cao , David J Ashline , E Ficko-Blean (1) , Anita S Klein

1 LBI2M - Laboratoire de Biologie Intégrative des Modèles Marins

The marine red alga Porphyra umbilicalis Kützing has high tolerance towards various abiotic stresses. In this study, the contents of floridoside, isofloridoside and trehalose were measured using gas chromatography mass spectrometry (GC-MS) in response to desiccation and rehydration treatments; these conditions are similar to the tidal cycles that P. umbilicalis experiences in its natural habitats. The GC-MS analysis showed that the concentration of floridoside and isofloridoside didn't change in response to desiccation as expected of compatible solutes. Genes involved in the synthesis of (iso)floridoside and trehalose were screened from the recently completed Porphyra genome, including four putative trehalose-6-phosphate synthase (TPS) genes, two putative trehalose-6-phoshpate phosphatase (TPP) genes, and one putative trehalose synthase/amylase (TreS) gene. According to the phylogenetic analysis, conserved domain analysis, and gene expression analysis, we suggest that the Pum4785 and Pum5014 genes are related to floridoside and isofloridoside synthesis, respectively, and that the Pum4637 gene is involved in trehalose synthesis. Our study verifies the occurrences of nanomolar concentrations trehalose in P. umbilicalis for the first time and identifies additional genes possibly encoding trehalose phosphate synthases.

Domaines: Sciences de l'environnement

Yuanyu Cao, David J Ashline, E Ficko-Blean, Anita S Klein. Trehalose and (iso)floridoside production under desiccation stress in red alga Porphyra umbilicalis and the genes involved in their synthesis. Journal of Phycology, 2020, ⟨10.1111/jpy.13057⟩. ⟨hal-03432792⟩