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Using surface‐templated electrophoretic deposition, arrays of polymer beads (photonic units) incorporating photo‐switchable DAE molecules are created, which can be reversibly and individually switched between high and low emission states by direct photo‐excitation, without any energy or electron transfer processes within the molecular system. The micropatterned array of these photonic units is spectroscopically characterized in detail and optimized with respect to both signal contrast and cross‐talk. The optimum optical parameters including laser intensity, wavelength and duration of irradiation are elucidated and ideal conditions for creating reversible on/off cycles in a micropatterned array are determined. 500 such cycles are demonstrated with no obvious on/off contrast attenuation. The ability to process binary information is demonstrated by selectively writing information to the given photonic unit, reading the resultant emissive signal pattern and finally erasing the information again, which in turn demonstrates the possibility of continuous recording. This basic study paves the way for building complex circuits using spatially well‐arranged photonic units. [ABSTRACT FROM AUTHOR]

Plant phytochromes perceive red and far-red light to elicit adaptations to the changing environment. Downstream physiological responses revolve around red-light-induced interactions with phytochrome-interacting factors (PIF). Phytochromes double as thermoreceptors, owing to the pronounced temperature dependence of thermal reversion from the light-adapted Pfr to the dark-adapted Pr state. Here, we assess whether thermoreception may extend to the phytochrome:PIF interactions. While the association between Arabidopsis (Arabidopsis thaliana) PHYTOCHROME B (PhyB) and several PHYTOCHROME-INTERACTING FACTOR (PIF) variants moderately accelerates with temperature, the dissociation does more so, thus causing net destabilization of the phytochrome:PIF complex. Markedly different temperature profiles of PIF3 and PIF6 might underlie stratified temperature responses in plants. Accidentally, we identify a photoreception mechanism under strong continuous light, where the extent of phytochrome:PIF complexation decreases with red-light intensity rather than increases. Mathematical modeling rationalizes this attenuation mechanism and ties it to rapid red-light-driven Pr⇄Pfr interconversion and complex dissociation out of Pr. Varying phytochrome abundance, e.g., during diurnal and developmental cycles, and interaction dynamics, e.g., across different PIFs, modify the nature and extent of attenuation, thus permitting light-response profiles more malleable than possible for the phytochrome Pr⇄Pfr interconversion alone. Our data and analyses reveal a photoreception mechanism with implications for plant physiology, optogenetics, and biotechnological applications., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society of Plant Biologists. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)