Circadian and Seasonal Regulation of the Phenylpropanoid Pathway in Arabidopsis
Date of Award
Fall 2023
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Molecular, Cellular, and Developmental Biology
First Advisor
Gendron, Joshua
Abstract
Abstract Circadian and Seasonal Regulation of the Phenylpropanoid Pathway in Arabidopsis Daniel Alejandro Tarté The phenylpropanoid pathway, pivotal for the synthesis of diverse secondary metabolites in plants, exhibits significant circadian clock-regulated gene expression. Though speculated, a master transcriptional regulator bridging the circadian clock and the pathway remained elusive. Our research shed light on PHENYLALANINE AMMONIA LYASE 1 (PAL1), a key enzyme steering phenylpropanoid synthesis. Using a novel PAL1promoter::Luciferase reporter and promoter-bashing experiments, we pinpointed a critical PAL1 promoter region and a cis-regulatory element, the CBS. While CBS perturbation dampened PAL1 rhythmic expression, it did not eradicate it, hinting at a potential secondary regulatory element. This study deciphers intricate links between the circadian machinery and the phenylpropanoid biosynthesis, paving the way for future explorations.Plants synchronize their life cycles with seasonal variations using photoperiod cues. While photoperiod-induced flowering is extensively studied, a holistic understanding of the transcriptional networks modulated by photoperiod is lacking. Using transcriptomics in Arabidopsis under varying photoperiods, we observed extensive photoperiod-driven gene expression alterations. Of note, our extensive analysis of the phenylpropanoid biosynthesis pathway revealed that flavonoids production is highly photoperiod-responsive, but lignin production is stable.
Recommended Citation
Tarte, Daniel Alejandro, "Circadian and Seasonal Regulation of the Phenylpropanoid Pathway in Arabidopsis" (2023). Yale Graduate School of Arts and Sciences Dissertations. 1227.
https://elischolar.library.yale.edu/gsas_dissertations/1227
