Project description:Translational control is a key regulatory step in the expression of genes as proteins. In plant cells, translational efficiency of mRNAs differs on different mRNA species, and the efficiency dynamically changes in various conditions. To gain a global view of translational control throughout growth and development, we performed genome-wide analysis of polysome association of mRNA over growth and leaf development in Arabidopsis thaliana by applying the mRNAs in polysome to DNA microarray. This analysis revealed that the degree of polysome association of mRNA had different levels depending on mRNA species, and the polysome association changed greatly throughout growth and development for each. In the growth stage, transcripts showed varying changes in polysome association from strongly depressed to unchanged degree, with the majority of transcripts showing dissociation from ribosomes. On the other hand, during leaf development, the polysome association of transcripts showed a normal distribution from repressed to activated mRNAs when comparing between expanding and expanded leaves. In addition, functional category analysis of the microarray data suggested that translational control has a physiological significance in plant growth and development process, especially in category of signaling and protein synthesis. Besides this, we compared changes in polysome association of mRNAs between various conditions and characterized translational controls in each. This result suggested that mRNAs translation might be controlled by complicated mechanisms for response to each condition. Our results highlight the importance of dynamic changes in mRNA translation in plant development and growth. Experiment using two-flactionated mRNA in 4 developmental stages, Polysomal mRNA vs. total mRNA. Biological replicates: 2. Compared 2DAG and 21DAG, or Young leaves and Mature leaves.
Project description:Translational control is a key regulatory step in the expression of genes as proteins. In plant cells, translational efficiency of mRNAs differs on different mRNA species, and the efficiency dynamically changes in various conditions. To gain a global view of translational control throughout growth and development, we performed genome-wide analysis of polysome association of mRNA over growth and leaf development in Arabidopsis thaliana by applying the mRNAs in polysome to DNA microarray. This analysis revealed that the degree of polysome association of mRNA had different levels depending on mRNA species, and the polysome association changed greatly throughout growth and development for each. In the growth stage, transcripts showed varying changes in polysome association from strongly depressed to unchanged degree, with the majority of transcripts showing dissociation from ribosomes. On the other hand, during leaf development, the polysome association of transcripts showed a normal distribution from repressed to activated mRNAs when comparing between expanding and expanded leaves. In addition, functional category analysis of the microarray data suggested that translational control has a physiological significance in plant growth and development process, especially in category of signaling and protein synthesis. Besides this, we compared changes in polysome association of mRNAs between various conditions and characterized translational controls in each. This result suggested that mRNAs translation might be controlled by complicated mechanisms for response to each condition. Our results highlight the importance of dynamic changes in mRNA translation in plant development and growth.
Project description:Translational control is a key regulatory step in the expression of genes as proteins. In plant cells, translational efficiency of mRNAs differs on different mRNA species, and the efficiency dynamically changes in various conditions. To gain a global view of translational control throughout growth and development, we performed genome-wide analysis of polysome association of mRNA over growth and leaf development in Arabidopsis thaliana by applying the mRNAs in polysome to DNA microarray. This analysis revealed that the degree of polysome association of mRNA had different levels depending on mRNA species, and the polysome association changed greatly throughout growth and development for each. In the growth stage, transcripts showed varying changes in polysome association from strongly depressed to unchanged degree, with the majority of transcripts showing dissociation from ribosomes. On the other hand, during leaf development, the polysome association of transcripts showed a normal distribution from repressed to activated mRNAs when comparing between expanding and expanded leaves. In addition, functional category analysis of the microarray data suggested that translational control has a physiological significance in plant growth and development process, especially in category of signaling and protein synthesis. Besides this, we compared changes in polysome association of mRNAs between various conditions and characterized translational controls in each. This result suggested that mRNAs translation might be controlled by complicated mechanisms for response to each condition. Our results highlight the importance of dynamic changes in mRNA translation in plant development and growth.
Project description:Translational control is a key regulatory step in the expression of genes as proteins. In plant cells, translational efficiency of mRNAs differs on different mRNA species, and the efficiency dynamically changes in various conditions. To gain a global view of translational control throughout growth and development, we performed genome-wide analysis of polysome association of mRNA over growth and leaf development in Arabidopsis thaliana by applying the mRNAs in polysome to DNA microarray. This analysis revealed that the degree of polysome association of mRNA had different levels depending on mRNA species, and the polysome association changed greatly throughout growth and development for each. In the growth stage, transcripts showed varying changes in polysome association from strongly depressed to unchanged degree, with the majority of transcripts showing dissociation from ribosomes. On the other hand, during leaf development, the polysome association of transcripts showed a normal distribution from repressed to activated mRNAs when comparing between expanding and expanded leaves. In addition, functional category analysis of the microarray data suggested that translational control has a physiological significance in plant growth and development process, especially in category of signaling and protein synthesis. Besides this, we compared changes in polysome association of mRNAs between various conditions and characterized translational controls in each. This result suggested that mRNAs translation might be controlled by complicated mechanisms for response to each condition. Our results highlight the importance of dynamic changes in mRNA translation in plant development and growth. Experiment using 4 developmental stages. Biological replicates: 2. Compared 2DAG and 21DAG, or Young leaves and Mature leaves.
Project description:Heat stress is one of the most prominent and deleterious environmental threads affecting plant growth and development. Upon high temperatures, plants launch specialized gene expression programs that promote stress protection and survival. These programs involve global and specific changes at the transcriptional and translational levels. However the coordination of these processes and their specific role in the establishment of the heat stress response is not fully elucidated. In this report, we have carried out a genome-wide analysis to simultaneously monitor the individual changes in the transcriptional and translational mRNA levels of Arabidopsis thaliana seedlings after the exposure to a heat shock stress. Our results demonstrated that, superimposed to transcription, translation exerts a wide but dual regulation of gene expression. For the majority of mRNAs, translation is severely repressed, causing a decreased of 50% of the association of the bulk of mRNAs to polysomes. However, some relevant mRNAs involved in different aspects of homeostasis maintenance follow a differential pattern of translation. Analysis of the sequence of the differentially translated mRNAs unravels that some features, like the 5M-BM-4UTR G+C content and the cDNA length, may take part in the discrimination mechanisms for mRNA polysome loading. Among the differential translated genes stand out master regulators of the stress response, highlighting the main role of translation in the early establishment of physiological response of plants to elevated temperatures. In total 8 ATH1 Affymetrix GeneChips were hybridized with all combinations of two factors: total mRNA/polysome-bound-RNA; 22M-BM-:C/38M-BM-:C. Two biological replicates per sample type were performed.
Project description:7d-old WT ler seedlings were submitted to 12h of non-stress (air) or hypoxia-stress treatment under low light conditions (45 uM m-2 s-2), and Total and Large Polysome RNA from both treatments were extracted and hybridized against Affymetrix genome chips. Values were used to evaluate changes in transcript abundance and transcript association with large polysomal complexes. TABLE 1 - Comparison between transcript abundance in non-stress and hypoxia-stress conditions. TABLE 2 - Comparison between transcript abundance in large polysome complexes (5 or more ribosomes per mRNA) in non-stress and 12 hypoxia-stress conditions. TABLE 3 - Proportion of total transcript that is associated with large polysome complexes (polysome loading) under non-stress conditions. Raw data (not normalized) TABLE 4 - Proportion of total transcript that is associated with large polysome complexes (polysome loading) under 12h of hypoxia-stress. Raw data (not normalized) Keywords: time-course
Project description:Poly(A)-tail length and mRNA deadenylation play important roles in post-transcriptional gene regulation. Here, we report the regulation of mRNA expression, half-life, and polysome association in mouse embryonic stem cells by the Cnot3 subunit in the Ccr4-Not mRNA deadenylase complex. To determine the consequence of Cnot3 deletion, Cnot3 conditional knockout ESCs were first treated with DMSO (WT) or 0.1μM 4-hydroxytamoxifen (4OHT, KO). 1. In one experiment, cells were collected 3 days after the 4OHT treatment and total RNAs were extracted and sequenced to determine changes in mRNA expression. 2. In the second experiment, cells were collected 3 days after the 4OHT treatment and polysome-associated RNAs were fractionated using a published protocol, purified, and sequenced to determine changes in polysome-association. 3. In the third experiment, cells were further treated with actinomycin D (10ug/ml) 2 days after the initial 4OHT treatment. Cells were collected at 0, 4, 8 hrs after actinomycin D treatment and total RNAs were extracted and sequenced to determine changes in mRNA half-life. Two biological replicates were carried out for each experiment. RNAs were extracted using RNA purification kits from Life Technologies, and RNA-seq libraries were prepared using Illumina TruSeq RNA library preparation kit.