A Cyanobacterial Phytochrome Two-Component Light Sensory System

• DOI: 10.1126/science.277.5331.1505
• Publication Date: 2002-07-27T09:44:47Z
• Authors: Kuo-Chen Yeh; Shu-Hsing Wu; John T. Murphy; J. Clark Lagarias
• Keywords: Phytochrome; Response regulator; Histidine kinase; Dephosphorylation; Two-component regulatory system; Phytochrome A

The biliprotein phytochrome regulates plant growth and developmental responses to the ambient light environment through an unknown mechanism. Biochemical analyses demonstrate that is ancient molecule evolved from a more compact sensor in cyanobacteria. cyanobacterial Cph1 light-regulated histidine kinase mediates red, far-red reversible phosphorylation of small response regulator, Rcp1 (response regulator for phytochrome), encoded by adjacent gene, thus implicating protein phosphorylation-dephosphorylation initial step signal transduction phytochrome.