Arabidopsis phytochromes C and E have different spectral characteristics from those of phytochromes A and B

FEBS Letters

Eichenberg, Klaus³  Rüdiger, Wolfhart²  Schäfer, Eberhard³  Paulo, Nicola²  Sharrock, Robert A.¹  Bäurle, Isabel³ 

[1] Department of Plant Sciences, Montana State University, Bozeman, MT 59717, USA;Botanisches Institut, Ludwig-Maximilian-Universität München, Menzingerstraße 67, D-80638 Munich, Germany;Institut für Biologie II, Albert-Ludwigs-Universität Freiburg, Schänzlestraße 1, D-79104 Freiburg, Germany

关键词: Photoreceptor;    Phytochrome;    Chromophore;    Dark reversion;    Spectroscopy;    Yeast;    HIR;    high irradiance response;    LFR;    low fluence response;    phyA;    phytochrome A;    PHYA;    cDNA of phytochrome A;    PHYA;    apoprotein of phytochrome A;    PHYA*;    phycocyanobilin adduct of phytochrome A;    PHYA**;    phytochromobilin adduct of phytochrome A (all abbreviations for phytochromes B;    C;    D;    and E analogous);    PCB;    phycocyanobilin;    PΦB;    phytochromobilin;    Pfr;    far-red light absorbing form of phytochrome;    Pr;    red light absorbing form of phytochrome;    Ptot;    total amount of phytochrome;    VLFR;    very low fluence response;   

DOI  :  10.1016/S0014-5793(00)01301-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

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.

【 授权许可】

Unknown