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Molecular mechanisms of temperature acclimation and adaptation in marine diatoms.

ABSTRACT: Diatoms are important contributors to marine primary production and the ocean carbon cycle, yet the molecular mechanisms that regulate their acclimation and adaptation to temperature are poorly understood. Here we use a transcriptomic approach to investigate the molecular mechanisms associated with temperature acclimation and adaptation in closely related colder- and warmer-adapted diatom species. We find evidence that evolutionary changes in baseline gene expression, which we termed transcriptional investment or divestment, is a key mechanism used by diatoms to adapt to different growth temperatures. Invested and divested pathways indicate that the maintenance of protein processing machinery and membrane structure, important short-term physiological mechanisms used to respond to temperature changes, are key elements associated with adaptation to different growth temperatures. Our results also indicate that evolutionary changes in the transcriptional regulation of acetyl-CoA associated pathways, including lipid and branched chain amino acid metabolism, are used by diatoms to balance photosynthetic light capture and metabolism with changes in growth temperature. Transcriptional investment and divestment can provide a framework to identify mechanisms of acclimation and adaption to temperature.

SUBMITTER: Liang Y

PROVIDER: S-EPMC6776047 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Molecular mechanisms of temperature acclimation and adaptation in marine diatoms.

Liang Yue Y Koester Julie A JA Liefer Justin D JD Irwin Andrew J AJ Finkel Zoe V ZV

The ISME journal 20190524 10

Diatoms are important contributors to marine primary production and the ocean carbon cycle, yet the molecular mechanisms that regulate their acclimation and adaptation to temperature are poorly understood. Here we use a transcriptomic approach to investigate the molecular mechanisms associated with temperature acclimation and adaptation in closely related colder- and warmer-adapted diatom species. We find evidence that evolutionary changes in baseline gene expression, which we termed transcripti ...[more]

PMID: 31127177

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Dataset Information

Molecular mechanisms of temperature acclimation and adaptation in marine diatoms.

Publications

Molecular mechanisms of temperature acclimation and adaptation in marine diatoms.

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