The long-term goal of this proposal is to understand how circadian clocks function within eukaryotic cells. The purpose of a circadian clock is to regulate cellular processes such that they occur at specific times of the day and night. Circadian clocks are found in all kingdoms of life and the presence of a functional circadian clock has been shown to confer enhanced fitness onto the organism. Forward genetic approaches to understanding clock function have been instrumental in numerous model organisms including Arabidopsis and our initial gene discovery program yielded a key clock gene, TOC1, and the founding member of a novel photoreceptor family, ZTL. The success of this gene discovery program validates the approach, although currently circadian screens in Arabdopsis are not saturated since we are still identifying novel clock genes. We will continue the characterization of existing mutants and isolate novel mutants by developing new reporters based on TOC1, a critical component identified from our previous screens. In addition, we will exploit reverse genetic approaches to explore hypotheses about the role of clock gene family members in the circadian clock. Given the ubiquity of circadian-regulated physiology, the identification of common clock components will have an impact on understanding the pacemaker mechanism and malfunctions associated with known features of human well-being.

Public Health Relevance

Almost all organisms possess circadian clocks that control daily rhythms in physiology, metabolism and behavior. The molecular architecture of these clocks appears similar amongst all organisms. Thus the advances learned in model systems such as Arabidopsis will be broadly applicable to understanding rhythms in humans and the known pathologies associated with their dysfunction in a wide range of diseases.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Research Project (R01)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-NCF-D (09))
Program Officer
Tompkins, Laurie
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of California San Diego
Schools of Arts and Sciences
La Jolla
United States
Zip Code
Tripathi, Prateek; Carvallo, Marcela; Hamilton, Elizabeth E et al. (2017) Arabidopsis B-BOX32 interacts with CONSTANS-LIKE3 to regulate flowering. Proc Natl Acad Sci U S A 114:172-177
Shani, Eilon; Salehin, Mohammad; Zhang, Yuqin et al. (2017) Plant Stress Tolerance Requires Auxin-Sensitive Aux/IAA Transcriptional Repressors. Curr Biol 27:437-444
Huang, He; Alvarez, Sophie; Bindbeutel, Rebecca et al. (2016) Identification of Evening Complex Associated Proteins in Arabidopsis by Affinity Purification and Mass Spectrometry. Mol Cell Proteomics 15:201-17
Breton, Ghislain; Kay, Steve A; Pruneda-Paz, José L (2016) Identification of Arabidopsis Transcriptional Regulators by Yeast One-Hybrid Screens Using a Transcription Factor ORFeome. Methods Mol Biol 1398:107-18
Taylor-Teeples, M; Lin, L; de Lucas, M et al. (2015) An Arabidopsis gene regulatory network for secondary cell wall synthesis. Nature 517:571-5
Waadt, Rainer; Manalansan, Bianca; Rauniyar, Navin et al. (2015) Identification of Open Stomata1-Interacting Proteins Reveals Interactions with Sucrose Non-fermenting1-Related Protein Kinases2 and with Type 2A Protein Phosphatases That Function in Abscisic Acid Responses. Plant Physiol 169:760-79
Kaiserli, Eirini; Páldi, Katalin; O'Donnell, Liz et al. (2015) Integration of Light and Photoperiodic Signaling in Transcriptional Nuclear Foci. Dev Cell 35:311-21
Nagel, Dawn H; Doherty, Colleen J; Pruneda-Paz, Jose L et al. (2015) Genome-wide identification of CCA1 targets uncovers an expanded clock network in Arabidopsis. Proc Natl Acad Sci U S A 112:E4802-10
Zhou, Yun; Liu, Xing; Engstrom, Eric M et al. (2015) Control of plant stem cell function by conserved interacting transcriptional regulators. Nature 517:377-80
Zheng, Xiao-Yu; Zhou, Mian; Yoo, Heejin et al. (2015) Spatial and temporal regulation of biosynthesis of the plant immune signal salicylic acid. Proc Natl Acad Sci U S A 112:9166-73

Showing the most recent 10 out of 31 publications