Summary: The ultraviolet (UV)-B wavelength (280–315 nm) is an indispensable component of the sunlight that reaches the earth’s surface. Long-wavelength and low-fluence UV-B specifically induces plant photomorphogenesis, which is characterized by inhibition of hypocotyl elongation, promotion of anthocyanin accumulation, and eventually tolerance against UV-B stress (Jenkins, 2009). In Arabidopsis thaliana, UV-B light is perceived by UV RESISTANCE LOCUS 8 (UVR8), a plant-specific chromoprotein. UVR8 forms a symmetric homodimer in the absence of UV-B light.

Link：http://www.cell.com/molecular-plant/fulltext/S1674-2052(16)30230-1