Project description:This study aim to understand how the long and short day flowering pathways are integrated and the mechanism of photoperiod perception in rice. Trascriptome at different time points under LD and SD conditions reveal that photoperiodism in rice is controlled by the evening complex. Mutants in LUX ARRYTHMO (LUX) and EARLY FLOWERING3 (ELF3) orthologs abolish flowering. We show that light causes a rapid and sustained degradation of ELF3-1, and this response is dependent on phyB. ChIP-seq of ELF3 and LUX reveal that EC controls both LD and SD flowering pathways by directly binding and suppressing the expression of key floral repressors, including PRR7 orthologs and Ghd7.
Project description:This study aim to understand how the long and short day flowering pathways are integrated and the mechanism of photoperiod perception in rice. Trascriptome at different time points under LD and SD conditions reveal that photoperiodism in rice is controlled by the evening complex. Mutants in LUX ARRYTHMO (LUX) and EARLY FLOWERING3 (ELF3) orthologs abolish flowering. We show that light causes a rapid and sustained degradation of ELF3-1, and this response is dependent on phyB. ChIP-seq of ELF3 and LUX reveal that EC controls both LD and SD flowering pathways by directly binding and suppressing the expression of key floral repressors, including PRR7 orthologs and Ghd7.
Project description:The Evening Complex (EC) is a core component of the circadian clock, which represses target gene expression at the end of the day and integrates temperature information in order to coordinate environmental and endogenous signals. Despite its importance, the mechanism of EC function remains unknown. Here we show that the EC recruits repressive chromatin domains to regulate the evening transcriptome. The EC component EARLY FLOWERING 3 (ELF3) directly interacts with a protein from the Swi2/Snf2-Related 1 (SWR1) complex to control deposition of H2A.Z-nucleosomes at the EC target genes. The SWR1 components display a circadian oscillation in gene expression with a peak at dusk, suggesting that the circadian clock controls the expression and function of SWR1. In turn, SWR1 is required for the circadian clockwork as defects in SWR1 activity alters morning-expressed genes. The EC-SWR1 complex binds to the promoters of the core clock genes PSEUDORESPONSE REGULATOR 7 (PRR7) and PRR9 and catalyzes H2A.Z deposition coincident with their repression at dusk. This provides a mechanism by which the circadian clock temporally establishes repressive chromatin domains to shape oscillatory gene expression around dusk.
Project description:In order to identify new miRNAs, NAT-siRNAs and possibly abiotic-stress regulated small RNAs in rice, three small RNA libraries were constructed from control rice seedlings and seedlings exposed to drought or salt stress, and then subjected to pyrosequencing.
Project description:This study was performed to study the effect of silicon (Si) nutrition on suberization and lignification in roots of rice. Besides physiological and histochemical examinations of the roots, transcription of candidate genes related to synthesis of suberin and lignin was investigated using microarray analysis. 14 days old rice seedlings (Oryza sativa, cv. Selenio) were cultivated for 28 days in non-aerated nutrient solution (mM: 1.43 NH4NO3, 0.32 NaH2PO4 x H2O, 0.51 K2SO4, 1 CaCl2 x 2 H2O, 1.6 MgSO4 x 7 H2O; µM: 1.82 MnSO4, 0.03 (NH4)6Mo7O24, 9 H3BO3, 0.3 ZnSO4 x 7 H2O and 0.15 CuSO4). The pH-value was adjusted to 6.0 by addition of 10 % (v/v) H2SO4 and 0.75 M KOH.Plants were supplied with Si in form of K2SiO3 at concentrations 0 ppm Si (control) and 50 ppm Si (1.78 mM) and potassium in the control treatment was balanced with K2SO4 supply. The plants were grown in a growth chamber (photoperiod: 14 h light, 10 h dark; temperature 25°C day / 20°C night; relative humidity 75 %; light intensity 220 µmol m2 s-1). Adventitious roots were harvested at 0-2 cm and 4-6 cm distance from the root tip and frozen immediately in liquid nitrogen. For RNA isolation, roots were ground under liquid nitrogen and total RNA was isolated using TRIsure® Reagent (Bioline, Luckenwalde, Germany) following the instructions of the manufacturer. To examine transcription of genes related to suberin and lignin synthesis, a self developed microarray containing amongst others ABC transporter, aclytransferases, ß-ketoacyl-CoA synthases and peroxidases was used .
Project description:5 leaves old rice plantlets were infected with Magnaporthe grisea spores and zero, two hours and twenty four houres after infection samples were collected
