Blue light and ultraviolet radiation

"Blue light and ultraviolet radiation" are not molecules or receptors but rather forms of electromagnetic radiation within specific wavelength ranges. **Blue light** typically refers to visible wavelengths between approximately 400–500 nm. **Ultraviolet (UV) radiation** is non-visible electromagnetic energy subdivided into UV-A (315–400 nm), UV-B (280–315 nm), and UV-C (<280 nm). These types of radiation act as environmental signals that are detected by specialized photoreceptor proteins in living organisms. In plants and animals, the biological effects of blue/UV light are mediated by dedicated photoreceptors such as cryptochromes and phototropins. Cryptochromes absorb both blue and some ultraviolet wavelengths; they play key roles in regulating circadian rhythms in animals[3], controlling growth responses in plants[1][2], mediating stress responses[1], and influencing developmental processes like flowering time[3]. In bacteria, similar flavin-based receptors exist for sensing these wavelengths[1]. Ultraviolet radiation can also directly cause DNA damage—especially at shorter wavelengths—leading to mutations that underlie diseases such as skin cancer. While "blue light/UV radiation" itself is not a therapeutic target or molecular entity suitable for drug targeting, the downstream signaling pathways activated by their respective photoreceptors may be considered targets for intervention. Because "blue light/UV radiation" does not refer to a single molecule or receptor but rather physical phenomena detected by various molecular sensors across species, it is not appropriate to classify it as a canonical therapeutic target. The correct approach would be to specify individual photoreceptor proteins such as "Cryptochrome 1," "Phototropin," or others depending on context[6][2][3].

Other names

Blue lightUltraviolet radiationUV radiationUV lightVisible blue spectrum