BLISTER-regulated vegetative growth is dependent on the protein kinase domain of ER stress modulator IRE1A in Arabidopsis thaliana
| Autor: | Julia Anna Kleinmanns, Daniel Schubert, Jian-Xiang Liu, Tao Qing, Zheng-Hui Hong |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Cancer Research
Arabidopsis thaliana Hydrolases Arabidopsis Gene Expression Plant Science QH426-470 Biochemistry 0302 clinical medicine Gene Expression Regulation Plant Gene expression ER stress modulator IRE1A Genetics (clinical) Plant Growth and Development 0303 health sciences biology Eukaryota Plants Endoplasmic Reticulum Stress Cell biology Enzymes Phenotypes Basic-Leucine Zipper Transcription Factors Root Growth Experimental Organism Systems Signal transduction Transcription Factors General Plant Shoots Research Article Nucleases Brassica Research and Analysis Methods BLISTER-regulated 03 medical and health sciences Model Organisms Ribonucleases Plant and Algal Models DNA-binding proteins Genetics Gene Regulation Protein kinase A Molecular Biology Transcription factor Ecology Evolution Behavior and Systematics 030304 developmental biology Arabidopsis Proteins fungi Organisms Biology and Life Sciences Proteins 500 Naturwissenschaften und Mathematik::570 Biowissenschaften Biologie::570 Biowissenschaften Biologie biology.organism_classification Regulatory Proteins Alternative Splicing Protein kinase domain Seedlings Unfolded protein response Unfolded Protein Response Animal Studies Enzymology Protein Kinases 030217 neurology & neurosurgery Developmental Biology Transcription Factors |
| Zdroj: | PLoS Genetics PLoS Genetics, Vol 15, Iss 12, p e1008563 (2019) |
| DOI: | 10.17169/refubium-26743 |
| Popis: | The unfolded protein response (UPR) is required for protein homeostasis in the endoplasmic reticulum (ER) when plants are challenged by adverse environmental conditions. Inositol-requiring enzyme 1 (IRE1), the bifunctional protein kinase / ribonuclease, is an important UPR regulator in plants mediating cytoplasmic splicing of the mRNA encoding the transcription factor bZIP60. This activates the UPR signaling pathway and regulates canonical UPR genes. However, how the protein activity of IRE1 is controlled during plant growth and development is largely unknown. In the present study, we demonstrate that the nuclear and Golgi-localized protein BLISTER (BLI) negatively controls the activity of IRE1A/IRE1B under normal growth condition in Arabidopsis. Loss-of-function mutation of BLI results in chronic up-regulation of a set of both canonical UPR genes and non-canonical UPR downstream genes, leading to cell death and growth retardation. Genetic analysis indicates that BLI-regulated vegetative growth phenotype is dependent on IRE1A/IRE1B but not their canonical splicing target bZIP60. Genetic complementation with mutation analysis suggests that the D570/K572 residues in the ATP-binding pocket and N780 residue in the RNase domain of IRE1A are required for the activation of canonical UPR gene expression, in contrast, the D570/K572 residues and D590 residue in the protein kinase domain of IRE1A are important for the induction of non-canonical UPR downstream genes in the BLI mutant background, which correlates with the shoot growth phenotype. Hence, our results reveal the important role of IRE1A in plant growth and development, and BLI negatively controls IRE1A’s function under normal growth condition in plants. Author summary When unfolded or misfolded proteins are accumulated in the ER, a much conserved response, called the unfolded protein response (UPR), is elicited to lighten the load of unfolded proteins in the ER by bringing the protein-folding and degradation capacities into alignment with the protein folding demands. However, over-activation of the UPR pathways under normal growth conditions affects plant growth and development. The bifunctional protein kinase / ribonuclease protein IRE1 is important for UPR gene regulation, but how IRE1’ protein activity is tightly controlled in plants is currently unknown. Here we report that BLISTER (BLI) negatively controls the IRE1’s function under normal growth condition in Arabidopsis. Through genetic analysis, our results also provide novel insights into how the protein kinase domain and ribonuclease domain contribute to the function of IRE1A in downstream gene expression. |
| Databáze: | OpenAIRE |
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