摘要：SummaryAureochromes represent a unique type of blue light photoreceptors that possess a blue light sensing flavin-binding LOV-domain and a DNA-binding bZIP domain, thus being light-driven transcription factors. The diatomPhaeodactylum tricornutum, a member of the essential marine primary producers, possesses four aureochromes (PtAUREO1a, 1b, 1c, 2). Here we show a dramatic change in the global gene expression pattern ofP. tricornutumwild-type cells after a shift from red to blue light. About 75% of the genes show significantly changed transcript levels already after 10 and 60 min of blue light exposure, which includes genes of major transcription factors as well as other photoreceptors. Very surprisingly, this light-induced regulation of gene expression is almost completely inhibited in independent PtAureo1a knockout lines. Such a massive and fast transcriptional change depending on one single photoreceptor is so far unprecedented. We conclude that PtAUREO1a plays a key role in diatoms upon blue light exposure.Graphical AbstractDisplay OmittedHighlights•Blue light induces a very fast transcriptional response in the diatomP. tricornutum•This strong response is almost completely inhibited when Aureochrome 1a is absent•The results imply a key role of PtAureo1a in blue light-induced responses in diatomsPhotonics; Plant Genetics; Plant Biology; Transcriptomics
