What is "phototropin"

n. (context protein English) Any of a class of photoreceptor flavoproteins that mediate phototropism in higher plants.

Phototropins are photoreceptor proteins (more specifically, flavoproteins) that mediate phototropism responses in higher plants. Along with cryptochromes and phytochromes they allow plants to respond and alter their growth in response to the light environment. Phototropins may also be important for the opening of stomata and the movement of chloroplasts.

Phototropins are part of the phototropic sensory system in plants that causes various environmental responses in plants. Phototropins specifically will cause stems to bend towards light, and stomata to open. Phototropins have been shown to impact the movement of chloroplast inside the cell. They also mediate the first changes in stem elongation in blue light (before cryptochromes become active) and phototropin 1 also is required for blue light mediated transcript destabilization of specific mRNAs in the cell.