Cytokinin regulates apical hook development via the coordinated actions of EIN3/EIL1 and PIF transcription factors in Arabidopsis

Abstract The apical hook is indispensable for protecting the delicate shoot apical meristem while dicot seedlings emerge from soil after germination in darkness. The development of the apical hook is co-ordinately regulated by multiple phytohormones and environmental factors. Yet, a holistic understanding of the spatial–temporal interactions between different phytohormones and environmental factors remains to be achieved. Using a chemical genetic approach, we identified kinetin riboside, as a proxy of kinetin, which promotes apical hook development of Arabidopsis thaliana in a partially ethylene-signaling-independent pathway. Further genetic and biochemical analysis revealed that cytokinin is able to regulate apical hook development via post-transcriptional regulation of the PHYTOCHROME INTERACTING FACTORs (PIFs), together with its canonical roles in inducing ethylene biosynthesis. Dynamic observations of apical hook development processes showed that ETHYLENE INSENSITVE3 (EIN3) and EIN3-LIKE1 (EIL1) are necessary for the exaggeration of hook curvature in response to cytokinin, while PIFs are crucial for the cytokinin-induced maintenance of hook curvature in darkness. Furthermore, these two families of transcription factors display divergent roles in light-triggered hook opening. Our findings reveal that cytokinin integrates ethylene signaling and light signaling via EIN3/EIL1 and PIFs, respectively, to dynamically regulate apical hook development during early seedling development.

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The Regulatory Mechanism of Water Activities on Aflatoxins Biosynthesis and Conidia Development, and Transcription Factor AtfB Is Involved in This Regulation

Toxins ◽

10.3390/toxins13060431 ◽

2021 ◽

Vol 13 (6) ◽

pp. 431

Author(s):

Longxue Ma ◽

Xu Li ◽

Xiaoyun Ma ◽

Qiang Yu ◽

Xiaohua Yu ◽

...

Keyword(s):

Transcription Factor ◽

Transcription Factors ◽

Environmental Factors ◽

Health Risks ◽

Sexual Development ◽

Regulatory Mechanism ◽

Food Storage ◽

Economic Losses ◽

Transcriptional Level ◽

Conidia Production

Peanuts are frequently infected by Aspergillus strains and then contaminated by aflatoxins (AF), which brings out economic losses and health risks. AF production is affected by diverse environmental factors, especially water activity (aw). In this study, A. flavus was inoculated into peanuts with different aw (0.90, 0.95, and 0.99). Both AFB1 yield and conidia production showed the highest level in aw 0.90 treatment. Transcriptional level analyses indicated that AF biosynthesis genes, especially the middle- and later-stage genes, were significantly up-regulated in aw 0.90 than aw 0.95 and 0.99. AtfB could be the pivotal regulator response to aw variations, and could further regulate downstream genes, especially AF biosynthesis genes. The expressions of conidia genes and relevant regulators were also more up-regulated at aw 0.90 than aw 0.95 and 0.99, suggesting that the relative lower aw could increase A. flavus conidia development. Furthermore, transcription factors involved in sexual development and nitrogen metabolism were also modulated by different aw. This research partly clarified the regulatory mechanism of aw on AF biosynthesis and A. flavus development and it would supply some advice for AF prevention in food storage.

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NAC transcription factors play an important role in ethylene biosynthesis, reception and signaling of tomato fruit ripening

Molecular Genetics and Genomics ◽

10.1007/s00438-016-1177-0 ◽

2016 ◽

Vol 291 (3) ◽

pp. 1205-1217 ◽

Cited By ~ 30

Author(s):

Xiaohong Kou ◽

Chen Liu ◽

Lihua Han ◽

Shuang Wang ◽

Zhaohui Xue

Keyword(s):

Transcription Factors ◽

Fruit Ripening ◽

Tomato Fruit ◽

Ethylene Biosynthesis ◽

Nac Transcription Factors ◽

Tomato Fruit Ripening

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Ribosome-Profiling Reveals Restricted Post Transcriptional Expression of Antiviral Cytokines and Transcription Factors during SARS-CoV-2 Infection

International Journal of Molecular Sciences ◽

10.3390/ijms22073392 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3392

Author(s):

Marina R. Alexander ◽

Aaron M. Brice ◽

Petrus Jansen van Vuren ◽

Christina L. Rootes ◽

Leon Tribolet ◽

...

Keyword(s):

Transcriptional Regulation ◽

Transcription Factors ◽

Host Response ◽

High Viral Load ◽

Ribosome Profiling ◽

Epithelial Cell Line ◽

Transcriptional Level ◽

Human Lung Epithelial Cell ◽

Post Transcriptional Regulation ◽

The Impact

The global COVID-19 pandemic caused by SARS-CoV-2 has resulted in over 2.2 million deaths. Disease outcomes range from asymptomatic to severe with, so far, minimal genotypic change to the virus so understanding the host response is paramount. Transcriptomics has become incredibly important in understanding host-pathogen interactions; however, post-transcriptional regulation plays an important role in infection and immunity through translation and mRNA stability, allowing tight control over potent host responses by both the host and the invading virus. Here, we apply ribosome profiling to assess post-transcriptional regulation of host genes during SARS-CoV-2 infection of a human lung epithelial cell line (Calu-3). We have identified numerous transcription factors (JUN, ZBTB20, ATF3, HIVEP2 and EGR1) as well as select antiviral cytokine genes, namely IFNB1, IFNL1,2 and 3, IL-6 and CCL5, that are restricted at the post-transcriptional level by SARS-CoV-2 infection and discuss the impact this would have on the host response to infection. This early phase restriction of antiviral transcripts in the lungs may allow high viral load and consequent immune dysregulation typically seen in SARS-CoV-2 infection.

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Pax5 Activates Oncogenic Transcription Factors of the Ets Family by Repressing the mir-15a/16-1 microRNA Cluster.

Blood ◽

10.1182/blood.v110.11.346.346 ◽

2007 ◽

Vol 110 (11) ◽

pp. 346-346

Author(s):

Elaine Y. Chung ◽

Diana Cozma ◽

Duonan Yu ◽

Michael Dews ◽

Erik A. Wentzel ◽

...

Keyword(s):

Transcription Factors ◽

B Cell ◽

Western Blotting ◽

Cell Receptor ◽

Lymphocytic Leukemia ◽

Mrna Levels ◽

Down Regulation ◽

Protein Levels ◽

Ets Family ◽

Post Transcriptional Regulation

Abstract We have recently demonstrated that Pax5 promotes B-lymphomagenesis by upregulating key components of B-cell receptor signaling [Cozma et al, J Clin Inv, 117 (8), 2007]. Gene regulation by Pax5 often involves complex formation with other oncogenic transcription factors of the Ets family, namely Myb and Ets1. We determined that expression of these proteins themselves depends on the presence of Pax5, as seen in human diffuse large B-cell lymphomas with Pax5 knockdown and murine lymphomas with epigenetic silencing of Pax5 [Yu et al, Blood, 101:1950–1955, 2003; Johnson et al, Nat Immunol, 5:853–861, 2004]. Upon reconstitution with the Pax5 gene, Myb and Ets1 levels increase sharply. This occurs with little increase in steady-state mRNA levels, suggesting post-transcriptional regulation, possibly by microRNAs. To test this hypothesis, we compared miRNA profiles of Pax5-deficieint and sufficient cells and discovered that several miRNAs are indeed repressed by Pax5. Among them is the miR-15a/16-1 cluster whose predicted targets include both Myb and Ets1. Consistent with this prediction, forced expression of miR-15a/16 brings down Myb and Ets1 protein levels. This is accompanied by impaired Pax5 function and overall suppression of B-lymphomagenesis. Thus, Ets family members (along with previously identified bcl-2) are key targets of the miR-15a/16 locus, a tumor suppressor in chronic lymphocytic leukemia. Interplay between Pax5, Myb/Ets1, and miR-15a/16-1. (A) Upregulation of Myb and Ets 1 in tumors over-expressing Pax5ER fusion, as compared to control GFP-only neoplasms. (B) Down-regulation of Myb and Ets1 in Pax5 tumors engineered to over-express the miR-15a/16-1 cluster. All panels depict Western blotting. Interplay between Pax5, Myb/Ets1, and miR-15a/16-1. (A) Upregulation of Myb and Ets 1 in tumors over-expressing Pax5ER fusion, as compared to control GFP-only neoplasms. (B) Down-regulation of Myb and Ets1 in Pax5 tumors engineered to over-express the miR-15a/16-1 cluster. All panels depict Western blotting.

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Synergistic Transcriptional and Post-Transcriptional Regulation of ESC Characteristics by Core Pluripotency Transcription Factors in Protein-Protein Interaction Networks

PLoS ONE ◽

10.1371/journal.pone.0105180 ◽

2014 ◽

Vol 9 (8) ◽

pp. e105180 ◽

Cited By ~ 5

Author(s):

Leijie Li ◽

Liangcai Zhang ◽

Guiyou Liu ◽

Rennan Feng ◽

Yongshuai Jiang ◽

...

Keyword(s):

Transcriptional Regulation ◽

Transcription Factors ◽

Protein Interaction ◽

Protein Interaction Networks ◽

Interaction Networks ◽

Protein Protein Interaction ◽

Protein Protein Interaction Networks ◽

Post Transcriptional Regulation

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Light modulates the gravitropic responses through organ-specific PIFs and HY5 regulation ofLAZY4expression inArabidopsis

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2005871117 ◽

2020 ◽

Vol 117 (31) ◽

pp. 18840-18848 ◽

Cited By ~ 3

Author(s):

Panyu Yang ◽

Qiming Wen ◽

Renbo Yu ◽

Xue Han ◽

Xing Wang Deng ◽

...

Keyword(s):

Transcription Factors ◽

Environmental Factors ◽

Plant Growth ◽

Molecular Basis ◽

Control Plant ◽

Protein Levels ◽

Positive Regulator ◽

Regulatory Module ◽

Organ Specific ◽

Negative Gravitropism

Light and gravity are two key environmental factors that control plant growth and architecture. However, the molecular basis of the coordination of light and gravity signaling in plants remains obscure. Here, we report that two classes of transcription factors, PHYTOCHROME INTERACTING FACTORS (PIFs) and ELONGATED HYPOCOTYL5 (HY5), can directly bind and activate the expression ofLAZY4, a positive regulator of gravitropism in both shoots and roots inArabidopsis. In hypocotyls, light promotes degradation of PIFs to reduceLAZY4expression, which inhibits the negative gravitropism of hypocotyls.LAZY4overexpression can partially rescue the negative gravitropic phenotype ofpifqin the dark without affecting amyloplast development. Our identification of the PIFs-LAZY4regulatory module suggests the presence of another role for PIF proteins in gravitropism, in addition to a previous report demonstrating that PIFs positively regulate amyloplast development to promote negative gravitropism in hypocotyls. In roots, light promotes accumulation of HY5 proteins to activate expression ofLAZY4, which promotes positive gravitropism in roots. Together, our data indicate that light exerts opposite regulation ofLAZY4expression in shoots and roots by mediating the protein levels of PIFs and HY5, respectively, to inhibit the negative gravitropism of shoots and promote positive gravitropism of roots inArabidopsis.

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The Catalytic Mechanism of Steroidogenic Cytochromes P450 from All-Atom Simulations: Entwinement with Membrane Environment, Redox Partners, and Post-Transcriptional Regulation

Catalysts ◽

10.3390/catal9010081 ◽

2019 ◽

Vol 9 (1) ◽

pp. 81 ◽

Cited By ~ 13

Author(s):

Angelo Spinello ◽

Ida Ritacco ◽

Alessandra Magistrato

Keyword(s):

Transcriptional Regulation ◽

Environmental Factors ◽

Catalytic Mechanism ◽

Current Knowledge ◽

Cytochromes P450 ◽

Specific Protein ◽

Chemical Transformations ◽

Redox Partners ◽

Novel Therapeutic Strategies ◽

Post Transcriptional Regulation

Cytochromes P450 (CYP450s) promote the biosynthesis of steroid hormones with major impact on the onset of diseases such as breast and prostate cancers. By merging distinct functions into the same catalytic scaffold, steroidogenic CYP450s enhance complex chemical transformations with extreme efficiency and selectivity. Mammalian CYP450s and their redox partners are membrane-anchored proteins, dynamically associating to form functional machineries. Mounting evidence signifies that environmental factors are strictly intertwined with CYP450s catalysis. Atomic-level simulations have the potential to provide insights into the catalytic mechanism of steroidogenic CYP450s and on its regulation by environmental factors, furnishing information often inaccessible to experimental means. In this review, after an introduction of computational methods commonly employed to tackle these systems, we report the current knowledge on three steroidogenic CYP450s—CYP11A1, CYP17A1, and CYP19A1—endowed with multiple catalytic functions and critically involved in cancer onset. In particular, besides discussing their catalytic mechanisms, we highlight how the membrane environment contributes to (i) regulate ligand channeling through these enzymes, (ii) modulate their interactions with specific protein partners, (iii) mediate post-transcriptional regulation induced by phosphorylation. The results presented set the basis for developing novel therapeutic strategies aimed at fighting diseases originating from steroid metabolism dysfunction.

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Molecular aspects of rheumatoid arthritis: chemokines, environmental factors and transcription factors

FEBS Journal ◽

10.1111/j.1742-4658.2008.06579.x ◽

2008 ◽

Vol 275 (18) ◽

pp. 4447-4447 ◽

Cited By ~ 3

Author(s):

Hiroshi Okamoto

Keyword(s):

Rheumatoid Arthritis ◽

Transcription Factors ◽

Environmental Factors ◽

Molecular Aspects

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Picture Your Nursing Home: Exploring the Sense of Home of Older Residents through Photography

Journal of Aging Research ◽

10.1155/2015/312931 ◽

2015 ◽

Vol 2015 ◽

pp. 1-11 ◽

Cited By ~ 12

Author(s):

J. van Hoof ◽

M. M. Verhagen ◽

E. J. M. Wouters ◽

H. R. Marston ◽

M. D. Rijnaard ◽

...

Keyword(s):

Quality Of Life ◽

Nursing Home ◽

Environmental Factors ◽

Built Environment ◽

Social Environment ◽

Nursing Home Residents ◽

The Social ◽

Holistic Understanding ◽

Sense Of Home

The quality of the built environment can impact the quality of life and the sense of home of nursing home residents. This study investigated (1) which factors in the physical and social environment correlate with the sense of home of the residents and (2) which environmental factors are most meaningful. Twelve participants engaged in a qualitative study, in which photography was as a supportive tool for subsequent interviews. The data were analysed based on the six phases by Braun and Clarke. The four themes identified are (1) the physical view; (2) mobility and accessibility; (3) space, place, and personal belongings; and (4) the social environment and activities. A holistic understanding of which features of the built environment are appreciated by the residents can lead to the design and retrofitting of nursing homes that are more in line with personal wishes.

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