Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Transcription profiling of Arabidopsis wild type and arrhythmic CCA1-34 line reveals that rhythmic growth is explained by coincidence between internal and external cues

ABSTRACT: Plant hypocotyls elongate in response to darkness. The response to darkness is gated by the circadian clock, such that wild-type plants (Col) only respond to darkness with growth once every 24 hours, whereas arrhythmic lines, such as CCA1-34, will respond to darkness with growth at any time of day. The experiment here was designed to find genes whose expression was correlated with growth. It should also pick up other genes that are gated by the circadian clock or that are direct targets of CCA1. Experiment Overall Design: Two genotypes were uses, wild-type (Col) and the arrhythmic CCA1-34 line that overexpresses the CCA1 protein. Plants were entrained in short day conditions for four days and then subjected light/dark pulses consisting of 160 minutes of light and 320 minutes of dark. We collected samples 120 minutes into the first and last dark periods of the day, corresponding to 280 and 1240 minutes after dawn. At the 280 minute time point Col plants are growing in response to darkness. At the 1240 minute time point Col plants are not growing. CCA1-34 plants are growing at both time points. The collection regime was continued for three days for a total of three temporal replicates for each time point/genotype combination.

ORGANISM(S): Arabidopsis thaliana

SUBMITTER: Julin Maloof

PROVIDER: E-GEOD-6906 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Rhythmic growth explained by coincidence between internal and external cues.

Nozue Kazunari K Covington Michael F MF Duek Paula D PD Lorrain Séverine S Fankhauser Christian C Harmer Stacey L SL Maloof Julin N JN

Nature 20070624 7151

Most organisms use circadian oscillators to coordinate physiological and developmental processes such as growth with predictable daily environmental changes like sunrise and sunset. The importance of such coordination is highlighted by studies showing that circadian dysfunction causes reduced fitness in bacteria and plants, as well as sleep and psychological disorders in humans. Plant cell growth requires energy and water-factors that oscillate owing to diurnal environmental changes. Indeed, two ...[more]

PMID: 17589502

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Dataset Information

Transcription profiling of Arabidopsis wild type and arrhythmic CCA1-34 line reveals that rhythmic growth is explained by coincidence between internal and external cues

Publications

Rhythmic growth explained by coincidence between internal and external cues.

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