p. 36913 Signals from Sunlight
- Lincoln Taiz, Lincoln TaizUniversity of California, Santa Cruz
- Eduardo Zeiger, Eduardo ZeigerUniversity of California, Los Angeles
- Ian Max MøllerIan Max MøllerAarhus University, Denmark
- , and Angus MurphyAngus MurphyUniversity of Maryland
Abstract
This chapter discusses how sunlight also serves as a signal that regulates various developmental processes, from seed germination to fruit development and senescence. In addition, sunlight provides directional cues for plant growth as well as non-directional cues for plant movements. The receptor molecules that plants use to detect sunlight are termed photoreceptors, which undergo a conformational change when irradiated by a particular wavelength of light (perceived by the eye as colour) to initiate signaling reactions that typically involve second messengers and phosphorylation cascades collectively referred to as photoresponses. The chapter then looks at the signaling mechanisms involved in light-regulated growth and development, focusing primarily on the receptors for red light, far-red light, blue light, and UV-B radiation. It considers phytochromes, cryptochromes, and phototropins.
