Seeing Without Eyes - Plants, Photoreceptors and Gene Expression

One of a series of articles for post-16 students published by Science and Plants for Schools (SAPS). Plants monitor the intensity, direction, colour and duration of the light they receive and use this information to adapt their growth and metabolism to their particular environment. Most plant responses to light require changes in gene expression. 

This booklet discusses recent research into how light absorption by phytochromes (a class of plant photoreceptors) alters gene transcription. The main text of the booklet analyses experiments on how phytochromes act after seedlings are exposed to light. It discusses the conversion of phytochromes from the red absorbing Pr form to the far red absorbing Pfr form; the light induced movement of phytochromes from the cytoplasm to the nucleus; and the interaction of phytochromes with transcription factors. 

The booklet also contains three boxes. ‘Microarrays’ briefly describes ‘gene chip’ technology. ‘Photoreceptors’ describes the fundamental similarities between phytochromes and opsins (the photoreceptors in the eye). ‘Seeing blue’ briefly describes how plants detect the UV and blue regions of the spectrum.