De novo transcriptomic profiling of halotolerant microalga Dunaliella salina (Chlorophyta) in response to reciprocal alteration of salinities.
Ontology highlight
ABSTRACT: The unicellular microalga Dunaliella salina is one of the halotolerant and cell wall-less green microalgae in Dunaliella genus. The ability of halotolerance in Dunaliella is attributed to the accumulation of glycerol. Both sugar made by photosynthesis and starch serve as carbon sources for glycerol biosynthesis. Quantitative PCR-based analyses concluded no apparent transcriptional regulation of glycerol, carbon fixation, and starch metabolisms upon salinity stresses. To examine whether or not transcriptional regulation is involved at the transcriptomic level, we assembled a de novo deep sequencing transcriptome. By using a pathway-based approach, we show that low- and high-salt (i.e., 0.5M versus 2M NaCl) adapted cells share a common transcriptomic profile and that subsets of ESTs associated with energy metabolisms are less affected upon salinity stress. We find that enzymes involved in glycerol, carbon fixation, and starch metabolisms are encoded by multiple EST isoforms. We show that EST isoforms encoding dihydroacetone reductase in glycerol metabolism, phosphoglycerate kinase in carbon fixation, and beta-amylase and fructobiphosphate aldolase in starch metabolism display a correlated transcriptional level change to the alteration of glycerol and starch contents upon salinity stresses. Taken together, our results demonstrate that some enzymes involved in glycerol, carbon fixation, and starch metabolisms are regulated at the transcriptional level upon salinity stresses. Furthermore, our analyses indicate that energy metabolisms are not drastically affected upon salinity stresses, consistent with its ability to adapt to a wide range of salinities.
ORGANISM(S): Dunaliella salina
PROVIDER: GSE74466 | GEO | 2017/02/22
REPOSITORIES: GEO
ACCESS DATA