Phytochrome C and Low Temperature Promote the Protein Accumulation and Red-Light Signaling of Phytochrome D

作者：Csaba Péter, Éva Ádám, Cornelia Klose, Gábor Grézal, Anita Hajdu, Gábor Steinbach, László Kozma‐Bognár, Dániel Silhavy, Ferenc Nagy, András Viczián · 发表于：Plant and Cell Physiology · 年份：2024 · DOI：10.1093/pcp/pcae089 · 被引用次数：6 · 研究领域：Light effects on plants、Plant Molecular Biology Research、Photosynthetic Processes and Mechanisms

Light affects almost every aspect of plant development. It is perceived by photoreceptors, among which phytochromes (PHY) are responsible for monitoring the red and far-red spectrum. Arabidopsis thaliana possesses five phytochrome genes (phyA-phyE). Whereas functions of phyA and phyB are extensively studied, our knowledge of other phytochromes is still rudimentary. To analyze phyD function, we expressed it at high levels in different phytochrome-deficient genetic backgrounds. Overexpressed phyD-YFP can govern effective light signaling but only at low temperatures and in cooperation with functional phyC. Under these conditions, phyD-YFP accumulates to high levels, and opposite to phyB, this pool is stable in light. By comparing the photoconvertible phyD-YFP and phyB levels and their signaling in continuous and pulsed irradiation, we showed that phyD-YFP is a less efficient photoreceptor than phyB. This conclusion is supported by the facts that only a part of the phyD-YFP pool is photoconvertible and that thermal reversion of phyD-YFP is faster than that of phyB. Our data suggest that the temperature-dependent function of phyD is based on the amount of phyD protein and not on its Pfr stability, as described for phyB. We also found that phyD-YFP and phyB-GFP are associated with strongly overlapping genomic locations and are able to mediate similar changes in gene expression; however, the efficiency of phyD-YFP is lower. Based on these data, we propose that under certain conditio...