Arabidopsis thaliana
Ontology highlight
ABSTRACT:
OTHER RELATED OMICS DATASETS IN: E-GEOD-11758
PROVIDER: PRJNA106053 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:In Arabidopsis thaliana the evolutionary conserved N-terminal acetyltransferase (Nat) complexes NatA and NatB co-translationally acetylate 60% of the proteome. Both have recently been implicated in the regulation of plant stress responses. While NatA mediates drought tolerance, NatB is required for pathogen resistance and the adaptation to high salinity and high osmolarity. Salt and osmotic stress impair protein folding and result in the accumulation of misfolded proteins in the endoplasmic reticulum (ER). The ER-membrane resident E3 ubiquitin ligase DOA10 targets misfolded proteins for degradation during ER stress and is conserved among eukaryotes. In yeast, DOA10 recognizes conditional degradation signals (Ac/N-degrons) created by NatA and NatB. Assuming that this mechanism is preserved in plants, the lack of Ac/N-degrons required for efficient removal of misfolded proteins might explain the sensitivity of NatB mutants to protein harming conditions. In this study, we investigate the response of NatB mutants to dithiothreitol (DTT) and tunicamycin (TM) induced ER stress. We report that NatB mutants are hypersensitive to DTT but not TM, suggesting that the DTT hypersensitivity is caused by an over-reduction of the cytosol rather than an accumulation of unfolded proteins in the ER. In line with this hypothesis, the cytosol of NatB depleted plants is constitutively over-reduced and a global transcriptome analysis reveals that their reductive stress response is permanently activated. Moreover, we demonstrate that doa10 mutants are susceptible to neither DTT nor TM, ruling out a substantial role of DOA10 in ER-associated protein degradation (ERAD) in plants. Contrary to previous findings in yeast, our data indicates that N-terminal acetylation (NTA) does not inhibit ER targeting of a substantial amount of proteins in plants. In summary, we provide further evidence that NatB-mediated imprinting of the proteome is vital for the response to protein-harming stress and rule out DOA10 as the sole recognin for substrates in the plant ERAD pathway.
2021-11-29 | GSE186324 | GEO
Project description:Cells maintain proteostasis by selectively recognizing and targeting misfolded proteins for degradation. In Saccharomyces cerevisiae, the Hsp70 nucleotide exchange factor Fes1 is essential for the degradation of chaperone-associated misfolded proteins by the ubiquitin-proteasome system. Here we show that the FES1 transcript undergoes unique 3' alternative splicing that results in two equally active isoforms with alternative C-termini, Fes1L and Fes1S. Fes1L is actively targeted to the nucleus and represents the first identified nuclear Hsp70 nucleotide exchange factor. In contrast, Fes1S localizes to the cytosol and is essential to maintain proteostasis. In the absence of Fes1S, the heat-shock response is constitutively induced at normally non-stressful conditions. Moreover, cells display severe growth defects when elevated temperatures, amino acid analogues or the ectopic expression of misfolded proteins, induce protein misfolding. Importantly, misfolded proteins are not targeted for degradation by the ubiquitin-proteasome system. These observations support the notion that cytosolic Fes1S maintains proteostasis by supporting the removal of toxic misfolded proteins by proteasomal degradation. This study provides key findings for the understanding of the organization of protein quality control mechanisms in the cytosol and nucleus. 4 strains (WT, fes1Î, fes1ÎS, fes1ÎL) were sequenced in triplicates from independent RNA isolations.
2016-02-29 | E-GEOD-78136 | biostudies-arrayexpress
Project description:Cells maintain proteostasis by selectively recognizing and targeting misfolded proteins for degradation. In Saccharomyces cerevisiae, the Hsp70 nucleotide exchange factor Fes1 is essential for the degradation of chaperone-associated misfolded proteins by the ubiquitin-proteasome system. Here we show that the FES1 transcript undergoes unique 3' alternative splicing that results in two equally active isoforms with alternative C-termini, Fes1L and Fes1S. Fes1L is actively targeted to the nucleus and represents the first identified nuclear Hsp70 nucleotide exchange factor. In contrast, Fes1S localizes to the cytosol and is essential to maintain proteostasis. In the absence of Fes1S, the heat-shock response is constitutively induced at normally non-stressful conditions. Moreover, cells display severe growth defects when elevated temperatures, amino acid analogues or the ectopic expression of misfolded proteins, induce protein misfolding. Importantly, misfolded proteins are not targeted for degradation by the ubiquitin-proteasome system. These observations support the notion that cytosolic Fes1S maintains proteostasis by supporting the removal of toxic misfolded proteins by proteasomal degradation. This study provides key findings for the understanding of the organization of protein quality control mechanisms in the cytosol and nucleus.
2016-02-29 | GSE78136 | GEO
Project description:Oligouridylate binding protein 1b functions in plant heat stress tolerance
| PRJNA313303 | ENA
Project description:Depleting cytosolic cysteine compromises the antioxidant capacity of the cytosol in Arabidopsis thaliana
| PRJNA120781 | ENA
Project description:Response to plant activator in Arabidopsis
| PRJNA95059 | ENA
Project description:Plant microRNAs undergo stepwise-nuclear maturation before engaging cytosolic sequence-complementary transcripts in association with the silencing-effector protein ARGONAUTE1(AGO1). How plant miRNAs translocate to the cytosol remains mysterious as does their cellular loading site(s) into AGO1. Here, we show that the N-termini of plant AGO1s contain a nuclear-localization (NLS) and nuclear-export signal (NES), which, in Arabidopsis thaliana (At) enables AtAGO1 nucleo-cytosolic shuttling in a Leptomycin-B-inhibited manner, diagnostic of CRM1(Expo1)/NES-dependent nuclear export. Nuclear-only AtAGO1 contains the same 2’O-methylated miRNA cohort as its nucleo-cytosolic counterpart, but specifically interacts with the miRNA loading-chaperone HSP90. AtAGO1 nucleo-cytosolic shuttling is required for mature miRNA translocation and for miRNA-mediated silencing. We propose that plant miRNAs are matured, methylated, loaded into AGO1 in the nucleus, and exported cytoplasmically as AGO1:miRNA complexes in a CRM1(Expo1)/NES-dependent manner.
2018-01-04 | GSE100395 | GEO
Project description:Evidence for plant epigenetic response to selection
| PRJNA773039 | ENA
Project description:Integrative genome-wide analysis reveals HLP1, a novel RNA-binding protein， regulates plant flowering by targeted alternative polyadenylation
| PRJNA169669 | ENA