Gene expression characterizes different nutritional strategies among three mixotrophic protists

Area of Science:

• Marine biology
• Microbial ecology
• Genomics

Background:

• Mixotrophic protists combine phototrophy and heterotrophy, playing vital ecological roles.
• Understanding their nutritional flexibility is crucial for marine biogeochemistry.
• Recent recognition of their importance necessitates detailed molecular investigation.

Purpose of the Study:

• To compare gene expression patterns of three mixotrophic protists under varying light and feeding conditions.
• To identify molecular mechanisms underlying mixotrophic nutrition and adaptation.
• To explore differences in gene regulation between obligate phototrophs and facultative heterotrophs.

Main Methods:

• RNA-sequencing (RNA-Seq) was employed to analyze gene expression.
• Three species (Prymnesium parvum, Dinobryon sp., Ochromonas sp.) were studied.
• Experiments were conducted under light and dark conditions with prey availability.

Main Results:

• Obligate phototrophs (P. parvum, Dinobryon sp.) showed significant gene expression changes between light and dark.
• Primarily heterotrophic Ochromonas sp. exhibited stable gene expression.
• Similarities in reproductive gene expression were observed between P. parvum and Dinobryon sp., but differences in carbon metabolism and phagotrophy genes were noted.

Conclusions:

• Gene expression patterns reveal distinct adaptive strategies in mixotrophic protists.
• Transcriptomic data offer insights into nitrogen source preference and stress responses.
• Molecular approaches are valuable for characterizing mixotrophic nutritional modes and identifying target genes for future research.