Phy tunes: phosphorylation status and phytochrome-mediated signaling.

ABSTRACT

Phytochromes are photoreceptors that regulate various aspects of plant growth and development. In this issue of Cell, Ryu et al. (2005) show that PAPP5, a type 5 protein phosphatase, acts on a biologically active phytochrome, increasing its stability and affinity for a downstream signal transducer and thus enhancing plant photoresponses.