Barley Hv CIRCADIAN CLOCK ASSOCIATED 1 and Hv PHOTOPERIOD H1 Are Circadian Regulators That Can Affect Circadian Rhythms in Arabidopsis.

Circadian clocks regulate many aspects of plant physiology and development that contribute to essential agronomic traits. Circadian clocks contain transcriptional feedback loops that are thought to generate circadian timing. There is considerable similarity in the genes that comprise the transcriptional and translational feedback loops of the circadian clock in the plant Kingdom. Functional characterisation of circadian clock genes has been restricted to a few model species. Here we provide a functional characterisation of the Hordeum vulgare (barley) circadian clock genes Hv circadian clock associated 1 (HvCCA1) and Hv photoperiodh1, which are respectively most similar to Arabidopsis thaliana circadian clock associated 1 (AtCCA1) and pseudo response regulator 7 (AtPRR7). This provides insight into the circadian regulation of one of the major crop species of Northern Europe. Through a combination of physiological assays of circadian rhythms in barley and heterologous expression in wild type and mutant strains of A. thaliana we demonstrate that HvCCA1 has a conserved function to AtCCA1. We find that Hv photoperiod H1 has AtPRR7-like functionality in A. thaliana and that the effects of the Hv photoperiod h1 mutation on photoperiodism and circadian rhythms are genetically separable.ZR is grateful to the National Institute of Agricultural Botany for the Award of Scholarship. We acknowledge funding from a Marie Curie Early Stage Training project MEST-CT-2005-020526 for JK and the BBSRC-DTP for funding SC. AARW and MCM are grateful to the BBSRC for the award of BBSRC Grant BB/M006212/1, which supported aspects of the study.This is the final published version. It first appeared at http://dx.doi.org/10.1371/journal.pone.012744

Research data supporting "Barley Hv CIRCADIAN CLOCK ASSOCIATED 1 and Hv PHOTOPERIOD H1 Are Circadian Regulators That Can Affect Circadian Rhythms in Arabidopsis"

These are the raw data files associated with Kusakina, J., Rutterford, Z., Cotter, S., Laurie, D. Greenland, A., Hall, A. and Webb, A.A.R. (2015) Barley Hv CIRCADIAN CLOCK ASSOCIATED 1 and Hv PHOTOPERIOD H1 are circadian regulators that can affect circadian rhythms in Arabidopsis. accepted for publication in PlosONE. 2015 The files describe circdian measurements of leaf movement (LM) delayed chlorphyll fluoresence DM, stomatal and photsynthesis, rhythms in Arabidopsis (Gas exchange) and Barley (Li-Cor) and hypoctyl extention and also flowering time (flowering) assays. The lines investigated are described in the relevent files and refer to Arabidopsis ecotypes (WS and Col-0), overexpressing barley CCA1 (n-n or Hv-CCA1-ox), over expressing Arabidopsis CCA1 (CCA1-ox), Arabidopsis wild tpyes or prr7-11 nulls expressing barley HvPPD-H1 or PPDh1 varients, and Igri and Triumph varities of barley. Measurements of ppdh1 variants in Arabidopsis under the control of the PRR7 promoter were performed by qPCR (qPCRResults)This work was supported by funding from the National Institute of Agricultural Botany, Marie Curie Early Stage Training project MEST-CT-2005- 020526 and the Biology and the Biological Sciences Research Council Doctoral Training Programm

Models and Data for Mombaerts et al., "Dynamical Differential Expression (DyDE) Reveals the Period Control Mechanisms of the Arabidopsis Circadian Oscillator", PLOS Computational Biology, 2019.

This dataset consists of experimental data that reveals the period control mechanisms of the Arabidopsis Circadian Oscillator (as described in the associated publication) and is provided here in an XLSX file. MATLAB code for performing the dynamic differential expression (DyDe) described in the publication are provided as .ZI

Estimates of period of circadian rhythms of (a) photosynthesis and (b) stomatal conductance in <i>HvPpd-H1</i> (filled circles) and <i>Hvppd-H1</i> (open circles) in constant white light of 100 μmol m^-2 s^-1 (black outlined symbols) or red light (red symbols).

<p>Each data point is derived from one individual seedling. Triangles represent the mean values.</p

Summary of circadian period estimates for leaf movement in Col-0, <i>prr7</i>-11 and <i>prr7-</i>11 transformed with either <i>pPRR7</i>::<i>Ppd-H1</i> or <i>pPRR7</i>::<i>ppd-H1</i>.

<p>* indicates significant difference at 5% level compared to background.</p><p>The background for <i>prr7</i>-11 is Col-0. The background for the complemented lines is <i>prr7</i>-11. SEM = standard error of the mean. %Rh = Percentage of rhythmic seedlings.</p><p>Summary of circadian period estimates for leaf movement in Col-0, <i>prr7</i>-11 and <i>prr7-</i>11 transformed with either <i>pPRR7</i>::<i>Ppd-H1</i> or <i>pPRR7</i>::<i>ppd-H1</i>.</p

Over expression of <i>HvCCA1</i> causes circadian arrhythmia in Arabidopsis.

<p>Normalised delayed chlorophyll fluorescence (a) and period estimates vs R.A.E (b) for Ws-2, Col-0, <i>AtCCA1</i>-ox (<i>AtCCA1</i>-ox 038) and two independent <i>HvCCA1-</i>ox transgenic lines (n = 8). Period estimates vs R.A.E for leaf movement in LL or individual leaves Col-0 and <i>AtCCA1</i>-ox (<i>AtCCA1</i>-ox 038) (c) and Ws-2 and two independent transgenic lines of <i>HvCAA1-ox</i> (d). <i>n</i> = 30. All experiments were independently repeated at least twice. Ws-2 (closed squares), Col-0 (closed triangles) <i>AtCCA1</i>-ox (open triangles) and two independent <i>HvCCA1-</i>ox transgenic lines (8–3 and 18–1) (open squares and diamonds).</p