Journal Article

Circadian rhythms of ethylene emission in Arabidopsis

Tobin, E.M, Thain, S.C, Vandenbussche, F, Straeten, D. van der, Dowson-Day, M.J, Laarhoven, L.J.J, Millar, A.J, Wang, Z.Y, Harren, F.J.M

2004

Overview

Ethylene controls multiple physiological processes in plants, including cell elongation. Consequently, ethylene synthesis is regulated by internal and external signals. We show that a light-entrained circadian clock regulates ethylene release from unstressed, wild-type Arabidopsis (Arabidopsis thaliana) seedlings, with a peak in the mid-subjective day. The circadian clock drives the expression of multiple ACC SYNTHASE genes, resulting in peak RNA levels at the phase of maximal ethylene synthesis. Ethylene production levels are tightly correlated with ACC SYNTHASE 8 steady-state transcript levels. The expression of this gene is controlled by light, by the circadian clock, and by negative feedback regulation through ethylene signaling. In addition, ethylene production is controlled by the TIMING OF CAB EXPRESSION 1 and CIRCADIAN CLOCK ASSOCIATED 1 genes, which are critical for all circadian rhythms yet tested in Arabidopsis. Mutation of ethylene signaling pathways did not alter the phase or period of circadian rhythms. Mutants with altered ethylene production or signaling also retained normal rhythmicity of leaf movement. We conclude that circadian rhythms of ethylene production are not critical for rhythmic growth.

• Publisher: American Society of Plant Biologists,American Society of Plant Physiologists
• Subject: 1-aminocyclopropane-1-carboxylate synthase / Agronomy. Soil science and plant productions / Amino Acids, Cyclic / Amino Acids, Cyclic - physiology / Arabidopsis / Arabidopsis - genetics / Arabidopsis - metabolism / Arabidopsis Proteins / Arabidopsis Proteins - physiology / Arabidopsis thaliana / Biological and medical sciences / Biosynthesis / circadian clock / Circadian Rhythm / circardian clock-associated 1 gene / Development and Hormone Action / Economic plant physiology / ethylene / Ethylene production / Ethylenes / Ethylenes - biosynthesis / feedback regulation, biochemical / Fundamental and applied biological sciences. Psychology / gas emissions / Gene expression regulation / Gene Expression Regulation, Plant / Genes / Genes. Genome / Genetic mutation / genetics / Growth and development / Growth regulators / Hypocotyls / Lyases / Lyases - metabolism / messenger RNA / metabolism / Molecular and cellular biology / Molecular genetics / molecular sequence data / Mutation / nucleotide sequences / physiology / Plant growth regulators / Plants / Seedlings / Seedlings - metabolism / Signal Transduction / timing of cab expression 1 gene / Transcription Factors / Transcription Factors - physiology