TY - JOUR
T1 - A light-sensing knot revealed by the structure of the chromophore-binding domain of phytochrome
AU - Wagner, Jeremiah R.
AU - Brunzelle, Joseph S.
AU - Forest, Katrina T.
AU - Vierstra, Richard D.
N1 - Funding Information:
Acknowledgements We thank B. Karniol, S. Beale and K. Satyshur for technical advice and acknowledge the Michigan Economic Development Corporation and the Michigan Technology Tri-Corridor for the support of this research program. Use of the Advanced Photon Source was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences. This work was supported by grants from the US National Science Foundation (R.D.V. and K.T.F.), the US Department of Energy (R.D.V.), and the W.M. Keck Foundation (K.T.F.).
PY - 2005/11/17
Y1 - 2005/11/17
N2 - Phytochromes are red/far-red light photoreceptors that direct photosensory responses across the bacterial, fungal and plant kingdoms. These include photosynthetic potential and pigmentation in bacteria as well as chloroplast development and photomorphogenesis in plants. Phytochromes consist of an amino-terminal region that covalently binds a single bilin chromophore, followed by a carboxy-terminal dimerization domain that often transmits the light signal through a histidine kinase relay. Here we describe the three-dimensional structure of the chromophore-binding domain of Deinococcus radiodurans phytochrome assembled with its chromophore biliverdin in the Pr ground state. Our model, refined to 2.5 Å resolution, reaffirms Cys 24 as the chromophore attachment site, locates key amino acids that form a solvent-shielded bilin-binding pocket, and reveals an unusually formed deep trefoil knot that stabilizes this region. The structure provides the first three-dimensional glimpse into the photochromic behaviour of these photoreceptors and helps to explain the evolution of higher plant phytochromes from prokaryotic precursors.
AB - Phytochromes are red/far-red light photoreceptors that direct photosensory responses across the bacterial, fungal and plant kingdoms. These include photosynthetic potential and pigmentation in bacteria as well as chloroplast development and photomorphogenesis in plants. Phytochromes consist of an amino-terminal region that covalently binds a single bilin chromophore, followed by a carboxy-terminal dimerization domain that often transmits the light signal through a histidine kinase relay. Here we describe the three-dimensional structure of the chromophore-binding domain of Deinococcus radiodurans phytochrome assembled with its chromophore biliverdin in the Pr ground state. Our model, refined to 2.5 Å resolution, reaffirms Cys 24 as the chromophore attachment site, locates key amino acids that form a solvent-shielded bilin-binding pocket, and reveals an unusually formed deep trefoil knot that stabilizes this region. The structure provides the first three-dimensional glimpse into the photochromic behaviour of these photoreceptors and helps to explain the evolution of higher plant phytochromes from prokaryotic precursors.
UR - http://www.scopus.com/inward/record.url?scp=27844461604&partnerID=8YFLogxK
U2 - 10.1038/nature04118
DO - 10.1038/nature04118
M3 - Article
C2 - 16292304
AN - SCOPUS:27844461604
SN - 0028-0836
VL - 438
SP - 325
EP - 331
JO - Nature
JF - Nature
IS - 7066
ER -