Study reveals how green algae adjust photosynthesis in response to different light wavelengths
Researchers found that the siphonous green alga Derbesia adopts fundamentally different photoacclimation strategies depending on the wavelength of light it receives. Blue and green light promoted metabolic activity and growth, while far-red and red light triggered a low-light-like survival response with reduced growth and suppressed core metabolism. The findings shed light on how coastal marine algae have evolved to exploit broad-spectrum sunlight and could inform future research on algal photobiology and biotechnology.
A study published on bioRxiv examined how the siphonous green alga Derbesia adjusts its photosynthetic and metabolic processes under five different light conditions—white, blue, green, red, and far-red—over a 10-day period using photobiological and transcriptomic analyses. The results revealed two contrasting acclimation strategies: blue and green light activated light-harvesting complexes, the transcriptional regulator MYB, ATPases, and hormone-signaling components, supporting active growth, while far-red and, to a lesser extent, red light induced responses resembling low-light stress, including enlarged antenna systems, chloroplast proliferation with aggregations, and reduced growth rates. Blue light additionally triggered a distinct transcriptional shift during prolonged exposure, enhancing cyclic electron transport and regulators of protein synthesis and DNA replication. Across all conditions, photosynthetic acclimation was primarily driven by changes in light-dependent reactions rather than downstream metabolic pathways. The consistently high activation of core metabolic processes under white light suggests Derbesia is evolutionarily adapted to the broad-spectrum light environment of shallow coastal habitats. The researchers also produced a draft genome of their Derbesia strain, which they offer as a genomic resource for future molecular photobiology studies in the algal order Bryopsidales.
What's missing
As a preprint, this study has not yet undergone formal peer review, so findings should be interpreted with caution. The study used a single Derbesia strain over 10 days under controlled laboratory conditions, leaving open questions about whether these acclimation responses generalize across strains, species, or natural field conditions with fluctuating light. The functional roles of many identified transcriptional regulators remain to be experimentally validated.
What different sources said
- bioRxivCenter
Thriving to surviving: light wavelength modulates photoacclimation response in the siphonous green alga Derbesia
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