SLIM1 Transcription Factor Promotes Sulfate Uptake and Distribution to Shoot, Along with Phytochelatin Accumulation, Under Cadmium Stress in Arabidopsis thaliana

Sulfur (S) assimilation, which is initiated by sulfate uptake, generates cysteine, the substrate for glutathione (GSH) and phytochelatin (PC) synthesis. GSH and PC contribute to cadmium (Cd) detoxification by capturing it for sequestration. Although Cd exposure is known to induce the expression of S-assimilating enzyme genes, including sulfate transporters (SULTRs), mechanisms of their transcriptional regulation are not well understood. Transcription factor SLIM1 controls transcriptional changes during S deficiency (−S) in Arabidopsis thaliana. We examined the potential involvement of SLIM1 in inducing the S assimilation pathway and PC accumulation. Cd treatment reduced the shoot fresh weight in the sulfur limitation1 (slim1) mutant but not in the parental line (1;2PGN). Cd-induced increases of sulfate uptake and SULTR1;2 expressions were diminished in the slim1 mutant, suggesting that SLIM1 is involved in inducing sulfate uptake during Cd exposure. The GSH and PC levels were lower in slim1 than in the parental line, indicating that SLIM1 was required for increasing PC during Cd treatment. Hence, SLIM1 indirectly contributes to Cd tolerance of plants by inducing −S responses in the cell caused by depleting the GSH pool, which is consumed by enhanced PC synthesis and sequestration to the vacuole.

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Specificity versus redundancy in the RAP2.4 transcription factor family of Arabidopsis thaliana: transcriptional regulation of genes for chloroplast peroxidases

BMC Plant Biology ◽

10.1186/s12870-017-1092-5 ◽

2017 ◽

Vol 17 (1) ◽

Cited By ~ 10

Author(s):

Radoslaw Rudnik ◽

Jote Tafese Bulcha ◽

Elena Reifschneider ◽

Ulrike Ellersiek ◽

Margarete Baier

Keyword(s):

Arabidopsis Thaliana ◽

Transcription Factor ◽

Transcriptional Regulation ◽

Transcription Factor Family

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A role for MED14 and UVH6 in heterochromatin transcription upon destabilization of silencing

Life Science Alliance ◽

10.26508/lsa.201800197 ◽

2018 ◽

Vol 1 (6) ◽

pp. e201800197 ◽

Cited By ~ 8

Author(s):

Pierre Bourguet ◽

Stève de Bossoreille ◽

Leticia López-González ◽

Marie-Noëlle Pouch-Pélissier ◽

Ángeles Gómez-Zambrano ◽

...

Keyword(s):

Dna Methylation ◽

Arabidopsis Thaliana ◽

Transcription Factor ◽

Environmental Changes ◽

Constitutive Heterochromatin ◽

Transcriptional Silencing ◽

Epigenetic Marks ◽

Transcriptional Changes ◽

Heterochromatin Silencing ◽

Insight Into

Constitutive heterochromatin is associated with repressive epigenetic modifications of histones and DNA which silence transcription. Yet, particular mutations or environmental changes can destabilize heterochromatin-associated silencing without noticeable changes in repressive epigenetic marks. Factors allowing transcription in this nonpermissive chromatin context remain poorly known. Here, we show that the transcription factor IIH component UVH6 and the mediator subunit MED14 are both required for heat stress–induced transcriptional changes and release of heterochromatin transcriptional silencing in Arabidopsis thaliana. We find that MED14, but not UVH6, is required for transcription when heterochromatin silencing is destabilized in the absence of stress through mutating the MOM1 silencing factor. In this case, our results raise the possibility that transcription dependency over MED14 might require intact patterns of repressive epigenetic marks. We also uncover that MED14 regulates DNA methylation in non-CG contexts at a subset of RNA-directed DNA methylation target loci. These findings provide insight into the control of heterochromatin transcription upon silencing destabilization and identify MED14 as a regulator of DNA methylation.

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Faculty Opinions recommendation of A membrane-tethered transcription factor defines a branch of the heat stress response in Arabidopsis thaliana.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.2542956.2191054 ◽

2010 ◽

Author(s):

David G Oppenheimer

Keyword(s):

Arabidopsis Thaliana ◽

Transcription Factor ◽

Heat Stress ◽

Stress Response ◽

Heat Stress Response

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Faculty Opinions recommendation of Post-transcriptional regulation of the Sef1 transcription factor controls the virulence of Candida albicans in its mammalian host.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717963075.793465696 ◽

2012 ◽

Author(s):

Malcolm Whiteway

Keyword(s):

Transcription Factor ◽

Transcriptional Regulation ◽

Candida Albicans ◽

Mammalian Host ◽

Post Transcriptional Regulation

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Growth and Antioxidant Responses in Iron-Biofortified Lentil under Cadmium Stress

Toxics ◽

10.3390/toxics9080182 ◽

2021 ◽

Vol 9 (8) ◽

pp. 182

Author(s):

Ruchi Bansal ◽

Swati Priya ◽

Harsh Kumar Dikshit ◽

Sherry Rachel Jacob ◽

Mahesh Rao ◽

...

Keyword(s):

Growth Parameters ◽

Dry Weight ◽

Cadmium Stress ◽

Antioxidant Enzyme Activities ◽

Limited Information ◽

Cd Stress ◽

Fresh Weight ◽

Cd Uptake ◽

Cd Tolerance ◽

Controlled Conditions

Cadmium (Cd) is a hazardous heavy metal, toxic to our ecosystem even at low concentrations. Cd stress negatively affects plant growth and development by triggering oxidative stress. Limited information is available on the role of iron (Fe) in ameliorating Cd stress tolerance in legumes. This study assessed the effect of Cd stress in two lentil (Lens culinaris Medik.) varieties differing in seed Fe concentration (L4717 (Fe-biofortified) and JL3) under controlled conditions. Six biochemical traits, five growth parameters, and Cd uptake were recorded at the seedling stage (21 days after sowing) in the studied genotypes grown under controlled conditions at two levels (100 μM and 200 μM) of cadmium chloride (CdCl2). The studied traits revealed significant genotype, treatment, and genotype × treatment interactions. Cd-induced oxidative damage led to the accumulation of hydrogen peroxide (H2O2) and malondialdehyde in both genotypes. JL3 accumulated 77.1% more H2O2 and 75% more lipid peroxidation products than L4717 at the high Cd level. Antioxidant enzyme activities increased in response to Cd stress, with significant genotype, treatment, and genotype × treatment interactions (p < 0.01). L4717 had remarkably higher catalase (40.5%), peroxidase (43.9%), superoxide dismutase (31.7%), and glutathione reductase (47.3%) activities than JL3 under high Cd conditions. In addition, L4717 sustained better growth in terms of fresh weight and dry weight than JL3 under stress. JL3 exhibited high Cd uptake (14.87 mg g−1 fresh weight) compared to L4717 (7.32 mg g−1 fresh weight). The study concluded that the Fe-biofortified lentil genotype L4717 exhibited Cd tolerance by inciting an efficient antioxidative response to Cd toxicity. Further studies are required to elucidate the possibility of seed Fe content as a surrogacy trait for Cd tolerance.

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Brassinosteroids repress the seed maturation program during the seed-to-seedling transition

Plant Physiology ◽

10.1093/plphys/kiab089 ◽

2021 ◽

Author(s):

Jiuxiao Ruan ◽

Huhui Chen ◽

Tao Zhu ◽

Yaoguang Yu ◽

Yawen Lei ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Transcription Factor ◽

Abscisic Acid ◽

Plant Hormone ◽

Flowering Plants ◽

Seed Maturation ◽

Domain Protein ◽

Abscisic Acid Insensitive3 ◽

Underlying Mechanisms ◽

Embryonic Structure

Abstract In flowering plants, repression of the seed maturation program is essential for the transition from the seed to the vegetative phase, but the underlying mechanisms remain poorly understood. The B3-domain protein VIVIPAROUS1/ABSCISIC ACID-INSENSITIVE3-LIKE 1 (VAL1) is involved in repressing the seed maturation program. Here we uncovered a molecular network triggered by the plant hormone brassinosteroid (BR) that inhibits the seed maturation program during the seed-to-seedling transition in Arabidopsis (Arabidopsis thaliana). val1-2 mutant seedlings treated with a BR biosynthesis inhibitor form embryonic structures, whereas BR signaling gain-of-function mutations rescue the embryonic structure trait. Furthermore, the BR-activated transcription factors BRI1-EMS-SUPPRESSOR 1 and BRASSINAZOLE-RESISTANT 1 bind directly to the promoter of AGAMOUS-LIKE15 (AGL15), which encodes a transcription factor involved in activating the seed maturation program, and suppress its expression. Genetic analysis indicated that BR signaling is epistatic to AGL15 and represses the seed maturation program by downregulating AGL15. Finally, we showed that the BR-mediated pathway functions synergistically with the VAL1/2-mediated pathway to ensure the full repression of the seed maturation program. Together, our work uncovered a mechanism underlying the suppression of the seed maturation program, shedding light on how BR promotes seedling growth.

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Ferroptosis is controlled by the coordinated transcriptional regulation of glutathione and labile iron metabolism by the transcription factor BACH1

Journal of Biological Chemistry ◽

10.1074/jbc.ra119.009548 ◽

2019 ◽

Vol 295 (1) ◽

pp. 69-82 ◽

Cited By ~ 18

Author(s):

Hironari Nishizawa ◽

Mitsuyo Matsumoto ◽

Tomohiko Shindo ◽

Daisuke Saigusa ◽

Hiroki Kato ◽

...

Keyword(s):

Transcription Factor ◽

Transcriptional Regulation ◽

Iron Metabolism ◽

Labile Iron

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Integrated transcription factor profiling with transcriptome analysis identifies L1PA2 transposons as global regulatory modulators in a breast cancer model

Scientific Reports ◽

10.1038/s41598-021-86395-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jiayue-Clara Jiang ◽

Joseph A. Rothnagel ◽

Kyle R. Upton

Keyword(s):

Breast Cancer ◽

Transcription Factor ◽

Transcriptional Regulation ◽

Disease Diagnosis ◽

Integrated Analysis ◽

Regulatory Sequences ◽

Cancer Model ◽

Mcf7 Cells ◽

Epithelial Cancers ◽

Breast Cancer Model

AbstractWhile transposons are generally silenced in somatic tissues, many transposons escape epigenetic repression in epithelial cancers, become transcriptionally active and contribute to the regulation of human gene expression. We have developed a bioinformatic pipeline for the integrated analysis of transcription factor binding and transcriptomic data to identify transposon-derived promoters that are activated in specific diseases and developmental states. We applied this pipeline to a breast cancer model, and found that the L1PA2 transposon subfamily contributes abundant regulatory sequences to co-ordinated transcriptional regulation in breast cancer. Transcription factor profiling demonstrates that over 27% of L1PA2 transposons harbour co-localised binding sites of functionally interacting, cancer-associated transcription factors in MCF7 cells, a cell line used to model breast cancer. Transcriptomic analysis reveals that L1PA2 transposons also contribute transcription start sites to up-regulated transcripts in MCF7 cells, including some transcripts with established oncogenic properties. In addition, we verified the utility of our pipeline on other transposon subfamilies, as well as on leukemia and lung carcinoma cell lines. We demonstrate that the normally quiescent regulatory activities of transposons can be activated and alter the cancer transcriptome. In particular, the L1PA2 subfamily contributes abundant regulatory sequences, and likely plays a global role in modulating breast cancer transcriptional regulation. Understanding the regulatory impact of L1PA2 on breast cancer genomes provides additional insights into cancer genome regulation, and may provide novel biomarkers for disease diagnosis, prognosis and therapy.

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