Transcript inhibition from limited starch degradation
Ontology highlight
ABSTRACT: In starchless mutants of Arabidopsis, pgm, and wild type, Col0, there are small differences in transcript levels at the end of the day, but large differences at the end of the night. Many of the transcripts of genes involved in biosynthesis and growth are repressed in the pgm mutant (Thimm et al., 2004). It is hypothesized that a transient depletion in sugars at the end of the night inhibits carbon utilization at the beginning of the day (Gibon et al., 2004). In order to test if the same inhibition of transcripts involved in biosynthesis and growth also occurs in starch excess mutants of Arabidopsis, Affymetrix arrays will be generated for WT (Col0), and the following mutants: sex4-3 (Salk 102567), ptpkis2 (Salk 053285), and sex1-3 (Yu et al., 2001). WT, sex4-3, and ptpkis2 plants were grown for 30 days and sex1-3 plants were grown for 36 days. All plants were grown in a growth chamber with a 12 hour photoperiod, quantum flux 100 mol m-2s-1, relative humidity was at least 75%, and a constant temperature of 20oC. Three leaves from 8 different plants of each genotype were harvested using a green safe lamp 0.5 hours before the lights came on in the morning and immediately frozen in LN2. Leaf material was powered using a mortar and pestle and RNA was extracted using a Purescript RNA isolation kit (Gentra Systems, MN, USA). Samples were then treated with DNaseI (Invitrogen, CA, USA). 12 samples were used in this experiment.
Project description:In starchless mutants of Arabidopsis, pgm, and wild type, Col0, there are small differences in transcript levels at the end of the day, but large differences at the end of the night. Many of the transcripts of genes involved in biosynthesis and growth are repressed in the pgm mutant (Thimm et al., 2004). It is hypothesized that a transient depletion in sugars at the end of the night inhibits carbon utilization at the beginning of the day (Gibon et al., 2004). In order to test if the same inhibition of transcripts involved in biosynthesis and growth also occurs in starch excess mutants of Arabidopsis, Affymetrix arrays will be generated for WT (Col0), and the following mutants: sex4-3 (Salk 102567), ptpkis2 (Salk 053285), and sex1-3 (Yu et al., 2001). WT, sex4-3, and ptpkis2 plants were grown for 30 days and sex1-3 plants were grown for 36 days. All plants were grown in a growth chamber with a 12 hour photoperiod, quantum flux 100 mol m-2s-1, relative humidity was at least 75%, and a constant temperature of 20oC. Three leaves from 8 different plants of each genotype were harvested using a green safe lamp 0.5 hours before the lights came on in the morning and immediately frozen in LN2. Leaf material was powered using a mortar and pestle and RNA was extracted using a Purescript RNA isolation kit (Gentra Systems, MN, USA). Samples were then treated with DNaseI (Invitrogen, CA, USA).
Project description:The aim of the experiment is to look at transcriptional changes in null mutants of APS kinase. There are four APS kinase isoforms in Arabidopsis, we are interested in the double mutant APK1/APK2, created by crossing two single salk lines. The transcriptomes of WT (Col-0) plants and the double knockout (ab) will be compared. The plants were grown under controlled environment conditions of 10h day, 14h night, 22 degrees centigrade, 60% humidity for five weeks. 10 whole rosettes were pooled for each replicate, there are three replicates for each genotype. Keywords: Expression profiling by array 6 samples were used in this experiment
Project description:How do transcript levels of leaf-expressed genes change in a normal day-night cycle of the phosphoglucomutase (pgm) mutant? The interest is in genes that are regulated by the circadian clock and the diurnal component (i.e. light, metabolite changes). Plants were grown on soil in a 12/12 h light/dark rhythm at 20°C day and night. 5 weeks after germination the rosettes of the non-flowering plants were harvested, 15 plants per sample. Plants were harvested in series at 6 times every 4 hours, beginning with the end of the night (still in darkness). Keywords: repeat
Project description:How do transcript levels of leaf-expressed genes change in a normal day-night cycle of the phosphoglucomutase (pgm) mutant? The interest is in genes that are regulated by the circadian clock and the diurnal component (i.e. light, metabolite changes). Plants were grown on soil in a 12/12 h light/dark rhythm at 20°C day and night. 5 weeks after germination the rosettes of the non-flowering plants were harvested, 15 plants per sample. Plants were harvested in series at 6 times every 4 hours, beginning with the end of the night (still in darkness). Experiment Overall Design: A diurnal time series (8 times) was analyzed.
Project description:In this progect, we anallyzed the phosphoproteome change of shoot and root from WT pgm mutant and sweet11/sweet12 mutant at the end of day and the end of night. The purpose is to understand the role of sugar distribution in shoot and root phopshoproteome.
Project description:The aim of the experiment is to look at transcriptional changes in null mutants of APS kinase. There are four APS kinase isoforms in Arabidopsis, we are interested in the double mutant APK1/APK2, created by crossing two single salk lines. The transcriptomes of WT (Col-0) plants and the double knockout (ab) will be compared. The plants were grown under controlled environment conditions of 10h day, 14h night, 22 degrees centigrade, 60% humidity for five weeks. 10 whole rosettes were pooled for each replicate, there are three replicates for each genotype. Keywords: Expression profilling by array
Project description:In addition to the canonical RNAi pathways that targets mRNAs in the cytoplasm, several RNA-dependent pathways operate in the nucleus to induce sequence-specific epigenetic modifications. One specialized type of RNAi-mediated pathway is RNA-directed DNA methylation (RdDM). During RdDM, nuclear DNA with sequence identity to the trigger dsRNA is de novo methylated at almost all cytosine residues, providing a mark for the formation of transcriptionally silent heterochromatin. Genetic forward screens identified the RPD3-like histone deacetylase HDA6 as the enzyme responsible for the histone deacetylation step of RdDM and suggest that HDA6 might have acquired specific functions for RNA-directed transcriptional silencing processes [Aufsatz et al., 2002a; Aufsatz et al., 2002b]. Complete loss-of-function mutants for AtHDA6 (rts1-1; RNA-mediated transcriptional gene silencing) exhibit reactivation of RdDM-silenced promoters, despite the continuous presence of the silencing-inducing RNA signal. One of the found mutant alleles, rts1-5, has an amino acid substitution located at a conserved position within the HDAC domain (Naumann et al., manuscript in preparation). This mutant is characterized by strong reactivation of an RdDM-silenced target promoter, despite maintaining wild-type levels of cytosine methylation. An evaluation of the transcription pattern among the mutants with opposite methylation phenotype and wild-type plants should show which genes are differentially regulated between the mutants in comparison to wild-type plants. Keywords: Expression profiling by array 9 samples were used in this experiment
Project description:We isolated Vascular specific root protoplast using the pWOL:GFP marker line (Birnbaum et al., 2003) and Fluorescence Activated Cell Sorting (FACS). FACS-treated root protoplast from wild type plants (Col0) were used as control. The GFP positive protoplast from the pWOL:GFP line and WT protoplast were used for a ChIP-seq experiment using H3K27me3 and H3K4me3 antibodies.
Project description:Transcriptional comparison of Arabidopsis thaliana pvip1;pvip2 RNAi double mutants against Col-0 wildtype. Tissue used: whole rosettes of 4-week-old plants grown under short-day conditions (8h light; 20oC). 3 biological replicates for each. Control = Col-0 and mutant = pvip1;pvip2. PVIP = Potyvirus-VPg-interacting protein (Dunoyer et al. 2004 J. Virol. 78: 2301-2309). 6 samples were used in this experiment.