Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

System responses to equal doses of photosynthetically usable radiation of blue, green, and red light in the marine diatom Phaeodactylum tricornutum.

ABSTRACT: We have studied the transcriptional, metabolic and photo-physiological responses to light of different spectral quality in the marine diatom Phaeodactylum tricornutum through time-series studies of cultures exposed to equal doses of photosynthetically usable radiation of blue, green and red light. The experiments showed that short-term differences in gene expression and profiles are mainly light quality-dependent. Transcription of photosynthesis-associated nuclear genes was activated mainly through a light quality-independent mechanism likely to rely on chloroplast-to-nucleus signaling. In contrast, genes encoding proteins important for photoprotection and PSII repair were highly dependent on a blue light receptor-mediated signal. Changes in energy transfer efficiency by light-harvesting pigments were spectrally dependent; furthermore, a declining trend in photosynthetic efficiency was observed in red light. The combined results suggest that diatoms possess a light quality-dependent ability to activate photoprotection and efficient repair of photodamaged PSII. In spite of approximately equal numbers of PSII-absorbed quanta in blue, green and red light, the spectral quality of light is important for diatom responses to ambient light conditions. Continuous, axenic culturing of P. tricornutum was done as described in Nymark et al. (2009). The cultures were incubated at 15M-BM-0C under cool white fluorescent light (Philips TLD 36W/96) providing a scalar irradiance (EPAR) of 100 M-NM-

ORGANISM(S): Phaeodactylum tricornutum

SUBMITTER: Per Winge

PROVIDER: E-GEOD-55959 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

System responses to equal doses of photosynthetically usable radiation of blue, green, and red light in the marine diatom Phaeodactylum tricornutum.

Valle Kristin Collier KC Nymark Marianne M Aamot Inga I Hancke Kasper K Winge Per P Andresen Kjersti K Johnsen Geir G Brembu Tore T Bones Atle M AM

PloS one 20141203 12

Due to the selective attenuation of solar light and the absorption properties of seawater and seawater constituents, free-floating photosynthetic organisms have to cope with rapid and unpredictable changes in both intensity and spectral quality. We have studied the transcriptional, metabolic and photo-physiological responses to light of different spectral quality in the marine diatom Phaeodactylum tricornutum through time-series studies of cultures exposed to equal doses of photosynthetically us ...[more]

PMID: 25470731

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Dataset Information

System responses to equal doses of photosynthetically usable radiation of blue, green, and red light in the marine diatom Phaeodactylum tricornutum.

Publications

System responses to equal doses of photosynthetically usable radiation of blue, green, and red light in the marine diatom Phaeodactylum tricornutum.

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