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Arabidopsis phytochromes C and E have different spectral characteristics from those of phytochromes A and B
Author(s) -
Eichenberg Klaus,
Bäurle Isabel,
Paulo Nicola,
Sharrock Robert A.,
Rüdiger Wolfhart,
Schäfer Eberhard
Publication year - 2000
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(00)01301-6
Subject(s) - phytochrome , phycocyanobilin , arabidopsis , phytochrome a , photomorphogenesis , far red , etiolation , chromophore , reversion , biology , arabidopsis thaliana , chemistry , biochemistry , botany , mutant , genetics , red light , gene , photochemistry , cyanobacteria , phycocyanin , bacteria , phenotype , enzyme
The red/far‐red light absorbing phytochromes play a major role as sensor proteins in photomorphogenesis of plants. In Arabidopsis the phytochromes belong to a small gene family of five members, phytochrome A (phyA) to E (phyE). Knowledge of the dynamic properties of the phytochrome molecules is the basis of phytochrome signal transduction research. Beside photoconversion and destruction, dark reversion is a molecular property of some phytochromes. A possible role of dark reversion is the termination of signal transduction. Since Arabidopsis is a model plant for biological and genetic research, we focussed on spectroscopic characterization of Arabidopsis phytochromes, expressed in yeast. For the first time, we were able to determine the relative absorption maxima and minima for a phytochrome C (phyC) as 661/725 nm and for a phyE as 670/724 nm. The spectral characteristics of phyC and E are strictly different from those of phyA and B. Furthermore, we show that both phyC and phyE apoprotein chromophore adducts undergo a strong dark reversion. Difference spectra, monitored with phycocyanobilin and phytochromobilin as the apoprotein's chromophore, and in vivo dark reversion of the Arabidopsis phytochrome apoprotein phycocyanobilin adducts are discussed with respect to their physiological function.