The Phytochromes

Abstract

Originally published in: Handbook of Photosensory Receptors. Edited by Winslow R. Briggs and John L. Spudich. Copyright © 2005 Wiley‐VCH Verlag GmbH & Co. KGaA Weinheim. Print ISBN: 3‐527‐31019‐7 The sections in this article are Introduction Photomorphogenesis and Phytochromes The Central Dogma of Phytochrome Action Molecular Properties of Eukaryotic and Prokaryotic Phytochromes Molecular Properties of Plant Phytochromes Molecular Properties of Cyanobacterial Phytochromes Photochemical and Nonphotochemical Conversions of Phytochrome The Phytochrome Chromophore Phytochrome Photointerconversions Dark Reversion Phytochrome Biosynthesis and Turnover Phytobilin Biosynthesis in Plants and Cyanobacteria Ferredoxin‐dependent Heme Oxygenases Ferredoxin‐dependent Phytobilin Synthases (Bilin Reductases) Apophytochrome Biosynthesis and Holophytochrome Assembly Apophytochrome Biosynthesis Holophytochrome Assembly Phytochrome Turnover Molecular Mechanism of Phytochrome Signaling: Future Perspective Regulation of Protein‐Protein Interactions by Phosphorylation Regulation of Tetrapyrrole Metabolism Acknowledgements

Phytochrome Induces Rapid PIF5 Phosphorylation and Degradation in Response to Red-Light Activation

“…Perception of these signals resides in the photoreceptor's capacity to switch reversibly between the biologically inactive Pr and the biologically active Pfr conformers upon sequential absorption of red (R) and far-red (FR) photons (Quail, 2002;Tu and Lagarias, 2005). Considerable progress has been made in recent years in defining the mechanisms by which the perceived light signals are transduced by the phy molecule to the photoresponsive nuclear genes that direct the plant's photomorphogenic behavior (Chen et al, 2004;Nagatani, 2004;Schepens et al, 2004;Duek and Fankhauser, 2005;Quail, 2006Quail, , 2007aQuail, , 2007bJiao et al, 2007), but much remains to be learned.…”