Cloning of the Arabidopsis Clock Gene TOC1, an Autoregulatory Response Regulator Homolog

• Published in: Science (American Association for the Advancement of Science) Vol. 289; no. 5480; pp. 768 - 771
• Main Authors: STRAYER, C, OYAMA, T, SCHULTZ, T. F, RAMAN, R, SOMERS, D. E, MAS, P, PANDA, S, KREPS, J. A, KAY, S. A
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for the Advancement of Science 04.08.2000; American Association for the Advancement of Science; The American Association for the Advancement of Science
• Subjects: Agronomy. Soil science and plant productions; Alleles; Amino Acid Motifs; Amino Acid Sequence; Arabidopsis; Arabidopsis - genetics; Arabidopsis - physiology; Arabidopsis Proteins; Biological and medical sciences; Biological Clocks - genetics; Biology and morphogenesis of the reproductive apparatus. Photoperiodism, vernalisation; Circadian rhythm; Circadian Rhythm - genetics; Cloning; Cloning, Molecular; DNA; DNA-Binding Proteins - chemistry; DNA-Binding Proteins - genetics; DNA-Binding Proteins - physiology; Economic plant physiology; Feedback; Feedback (Response); Flowering, floral biology, reproduction patterns; Flowers & plants; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Plant; Genes; Genes, Plant; Genetic aspects; Genetic engineering; Genetic mutation; Genetics; Growth and development; Literary Devices; Logical Thinking; Molecular Sequence Data; Mutation; Mutation, Missense; Nucleotides; Phenotype; Phenotypes; Photoperiod; Plant physiology and development; Plant Proteins - chemistry; Plant Proteins - genetics; Plant Proteins - physiology; Plants; Plants, Genetically Modified; Regulator genes; Repetitive Sequences, Amino Acid; RNA, Messenger - genetics; RNA, Messenger - metabolism; RNA, Plant - genetics; RNA, Plant - metabolism; Seedlings; Telomeres; TOC1 gene; Transcription Factors - chemistry; Transcription Factors - genetics; Transcription Factors - physiology; Transcription, Genetic; Transcripts (Written Records); Vegetative and sexual reproduction, floral biology, fructification; Transcription; Feedback regulation; Photoperiod; Circadian rhythm; Gene expression; Genetic determinism; Arabidopsis thaliana; Regulation(control); Gene; Cruciferae; Dicotyledones; Light; Angiospermae; Development; Flowering; Spermatophyta; Mutation; Experimental plant
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.289.5480.768

The toc1 mutation causes shortened circadian rhythms in light-grown Arabidopsis plants. Here, we report the same toc1 effect in the absence of light input to the clock. We also show that TOC1 controls photoperiodic flowering response through clock function. The TOC1 gene was isolated and found to encode a nuclear protein containing an atypical response regulator receiver domain and two motifs that suggest a role in transcriptional regulation: a basic motif conserved within the CONSTANS family of transcription factors and an acidic domain. TOC1 is itself circadianly regulated and participates in a feedback loop to control its own expression.