Light signals are required for the induction and regulation of many developmental processes in plants. Genetic analysis demonstrates that light responses are not simply endpoints of linear signal transduction pathways, but are the result of the integration of signals from a variety of photoreceptor systems. The phytochromes are red/far-red light absorbing receptors that have been shown to be light-regulated serine/threonine kinases. The subcellular location of phytochromes is regulated by light, being cytoplasmic in the dark, and imported to discrete nuclear sites in the light. Genetic and molecular analyses have identified a number of proteins that act downstream from phytochromes, in both the cytoplasmic and nuclear compartments, however traditional genetic screens have not identified all the components of the regulatory circuitry. Moreover, many mechanistic details are simply not known. It is proposed to use molecular, biochemical and genetic strategies to identify and characterize signal transduction components that act early in phytochrome signal transduction pathways. The primary aims of these studies are (1) to determine the mechanism of cytosolic retention of phytochrome B by PKS1, a cytoplasmic phosphoprotein; (2) to identify proteins involved in phytochrome B localization to subnuclear pool; (3) to characterize new components in the PHY signaling pathways identified in genetic screens; and (4) to assess the level of protein trafficking in response to light. In summary, the proposed experiments will further our knowledge of phytochrome-mediated signal transduction pathways, and will address the mechanism by which phytochromes transmit light signals to regulate such diverse responses as changes in gene expression, cell expansion and division, and chloroplast development. The long-term objective is to completely understand the signal transduction networks that allow plants to perceive and respond to their local light environment, and to relate this to general mechanisms of signal transduction in other organisms.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM052413-10
Application #
6795564
Study Section
Cell Development and Function Integrated Review Group (CDF)
Program Officer
Shapiro, Bert I
Project Start
1995-05-01
Project End
2007-08-31
Budget Start
2004-09-01
Budget End
2005-08-31
Support Year
10
Fiscal Year
2004
Total Cost
$329,353
Indirect Cost
Name
Salk Institute for Biological Studies
Department
Type
DUNS #
078731668
City
La Jolla
State
CA
Country
United States
Zip Code
92037
Liu, Wanlu; Duttke, Sascha H; Hetzel, Jonathan et al. (2018) RNA-directed DNA methylation involves co-transcriptional small-RNA-guided slicing of polymerase V transcripts in Arabidopsis. Nat Plants 4:181-188
Perrella, Giorgio; Davidson, Mhairi L H; O'Donnell, Liz et al. (2018) ZINC-FINGER interactions mediate transcriptional regulation of hypocotyl growth in Arabidopsis. Proc Natl Acad Sci U S A 115:E4503-E4511
Conn, Adam; Pedmale, Ullas V; Chory, Joanne et al. (2017) A Statistical Description of Plant Shoot Architecture. Curr Biol 27:2078-2088.e3
Qiu, Yongjian; Pasoreck, Elise K; Reddy, Amit K et al. (2017) Mechanism of early light signaling by the carboxy-terminal output module of Arabidopsis phytochrome B. Nat Commun 8:1905
Ge, Yanhua; Yan, Fenglian; Zourelidou, Melina et al. (2017) SHADE AVOIDANCE 4 Is Required for Proper Auxin Distribution in the Hypocotyl. Plant Physiol 173:788-800
Seluzicki, Adam; Burko, Yogev; Chory, Joanne (2017) Dancing in the dark: darkness as a signal in plants. Plant Cell Environ 40:2487-2501
Pedmale, Ullas V; Huang, Shao-Shan Carol; Zander, Mark et al. (2016) Cryptochromes Interact Directly with PIFs to Control Plant Growth in Limiting Blue Light. Cell 164:233-245
Zhang, Yijuan; Wen, Chunhong; Liu, Songbai et al. (2016) Shade avoidance 6 encodes an Arabidopsis flap endonuclease required for maintenance of genome integrity and development. Nucleic Acids Res 44:1271-84
Hetzel, Jonathan; Duttke, Sascha H; Benner, Christopher et al. (2016) Nascent RNA sequencing reveals distinct features in plant transcription. Proc Natl Acad Sci U S A 113:12316-12321
Zheng, Zuyu; Guo, Yongxia; Novák, Ond?ej et al. (2016) Local auxin metabolism regulates environment-induced hypocotyl elongation. Nat Plants 2:16025

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