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Kumar S, Mashkoor M, Balamurugan P, Grove A. Yeast Crf1p is an activator with different roles in regulation of target genes. Yeast 2024; 41:379-400. [PMID: 38639144 DOI: 10.1002/yea.3939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 04/02/2024] [Accepted: 04/09/2024] [Indexed: 04/20/2024] Open
Abstract
Under stress conditions, ribosome biogenesis is downregulated. This process requires that expression of ribosomal RNA, ribosomal protein, and ribosome biogenesis genes be controlled in a coordinated fashion. The mechanistic Target of Rapamycin Complex 1 (mTORC1) participates in sensing unfavorable conditions to effect the requisite change in gene expression. In Saccharomyces cerevisiae, downregulation of ribosomal protein genes involves dissociation of the activator Ifh1p in a process that depends on Utp22p, a protein that also functions in pre-rRNA processing. Ifh1p has a paralog, Crf1p, which was implicated in communicating mTORC1 inhibition and hence was perceived as a repressor. We focus here on two ribosomal biogenesis genes, encoding Utp22p and the high mobility group protein Hmo1p, both of which are required for communication of mTORC1 inhibition to target genes. Crf1p functions as an activator on these genes as evidenced by reduced mRNA abundance and RNA polymerase II occupancy in a crf1Δ strain. Inhibition of mTORC1 has distinct effects on expression of HMO1 and UTP22; for example, on UTP22, but not on HMO1, the presence of Crf1p promotes the stable depletion of Ifh1p. Our data suggest that Crf1p functions as a weak activator, and that it may be required to prevent re-binding of Ifh1p to some gene promoters after mTORC1 inhibition in situations when Ifh1p is available. We propose that the inclusion of genes encoding proteins required for mTORC1-mediated downregulation of ribosomal protein genes in the same regulatory circuit as the ribosomal protein genes serves to optimize transcriptional responses during mTORC1 inhibition.
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Affiliation(s)
- Sanjay Kumar
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Muneera Mashkoor
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Priya Balamurugan
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Anne Grove
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, USA
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2
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Tai YT, Fukuda T, Morozumi Y, Hirai H, Oda AH, Kamada Y, Akikusa Y, Kanki T, Ohta K, Shiozaki K. Fission Yeast TORC1 Promotes Cell Proliferation through Sfp1, a Transcription Factor Involved in Ribosome Biogenesis. Mol Cell Biol 2023; 43:675-692. [PMID: 38051102 PMCID: PMC10761059 DOI: 10.1080/10985549.2023.2282349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 10/29/2023] [Accepted: 11/06/2023] [Indexed: 12/07/2023] Open
Abstract
Target of rapamycin complex 1 (TORC1) is activated in response to nutrient availability and growth factors, promoting cellular anabolism and proliferation. To explore the mechanism of TORC1-mediated proliferation control, we performed a genetic screen in fission yeast and identified Sfp1, a zinc-finger transcription factor, as a multicopy suppressor of temperature-sensitive TORC1 mutants. Our observations suggest that TORC1 phosphorylates Sfp1 and protects Sfp1 from proteasomal degradation. Transcription analysis revealed that Sfp1 positively regulates genes involved in ribosome production together with two additional transcription factors, Ifh1/Crf1 and Fhl1. Ifh1 physically interacts with Fhl1, and the nuclear localization of Ifh1 is regulated in response to nutrient levels in a manner dependent on TORC1 and Sfp1. Taken together, our data suggest that the transcriptional regulation of the genes involved in ribosome biosynthesis by Sfp1, Ifh1, and Fhl1 is one of the key pathways through which nutrient-activated TORC1 promotes cell proliferation.
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Affiliation(s)
- Yen Teng Tai
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, Japan
| | - Tomoyuki Fukuda
- Department of Cellular Physiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Yuichi Morozumi
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, Japan
| | - Hayato Hirai
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Arisa H. Oda
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Yoshiaki Kamada
- National Institute for Basic Biology, Okazaki, Aichi, Japan
- Graduate University for Advanced Studies (SOKENDAI), Hayama, Kanagawa, Japan
| | - Yutaka Akikusa
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, Japan
| | - Tomotake Kanki
- Department of Cellular Physiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Kunihiro Ohta
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Kazuhiro Shiozaki
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, Japan
- Department of Microbiology and Molecular Genetics, University of California, Davis, California, USA
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3
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Ling B, Xu Y, Qian S, Xiang Z, Xuan S, Wu J. Regulation of hematopoietic stem cells differentiation, self-renewal, and quiescence through the mTOR signaling pathway. Front Cell Dev Biol 2023; 11:1186850. [PMID: 37228652 PMCID: PMC10203478 DOI: 10.3389/fcell.2023.1186850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 04/28/2023] [Indexed: 05/27/2023] Open
Abstract
Hematopoietic stem cells (HSCs) are important for the hematopoietic system because they can self-renew to increase their number and differentiate into all the blood cells. At a steady state, most of the HSCs remain in quiescence to preserve their capacities and protect themselves from damage and exhaustive stress. However, when there are some emergencies, HSCs are activated to start their self-renewal and differentiation. The mTOR signaling pathway has been shown as an important signaling pathway that can regulate the differentiation, self-renewal, and quiescence of HSCs, and many types of molecules can regulate HSCs' these three potentials by influencing the mTOR signaling pathway. Here we review how mTOR signaling pathway regulates HSCs three potentials, and introduce some molecules that can work as the regulator of HSCs' these potentials through the mTOR signaling. Finally, we outline the clinical significance of studying the regulation of HSCs three potentials through the mTOR signaling pathway and make some predictions.
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Affiliation(s)
- Bai Ling
- Department of Pharmacy, The Yancheng Clinical College of Xuzhou Medical University, The First People’s Hospital of Yancheng, Yancheng, Jiangsu, China
| | - Yunyang Xu
- Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Siyuan Qian
- The Second School of Clinical Medicine, Wenzhou Medical University, Wenzhou, China
| | - Ze Xiang
- Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Shihai Xuan
- Department of Laboratory Medicine, The People’s Hospital of Dongtai City, Dongtai, China
| | - Jian Wu
- Department of Clinical Laboratory, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou Municipal Hospital, Gusu School, Nanjing Medical University, Suzhou, Jiangsu, China
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4
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Gutiérrez-Santiago F, Navarro F. Transcription by the Three RNA Polymerases under the Control of the TOR Signaling Pathway in Saccharomyces cerevisiae. Biomolecules 2023; 13:biom13040642. [PMID: 37189389 DOI: 10.3390/biom13040642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/30/2023] [Accepted: 04/02/2023] [Indexed: 04/05/2023] Open
Abstract
Ribosomes are the basis for protein production, whose biogenesis is essential for cells to drive growth and proliferation. Ribosome biogenesis is highly regulated in accordance with cellular energy status and stress signals. In eukaryotic cells, response to stress signals and the production of newly-synthesized ribosomes require elements to be transcribed by the three RNA polymerases (RNA pols). Thus, cells need the tight coordination of RNA pols to adjust adequate components production for ribosome biogenesis which depends on environmental cues. This complex coordination probably occurs through a signaling pathway that links nutrient availability with transcription. Several pieces of evidence strongly support that the Target of Rapamycin (TOR) pathway, conserved among eukaryotes, influences the transcription of RNA pols through different mechanisms to ensure proper ribosome components production. This review summarizes the connection between TOR and regulatory elements for the transcription of each RNA pol in the budding yeast Saccharomyces cerevisiae. It also focuses on how TOR regulates transcription depending on external cues. Finally, it discusses the simultaneous coordination of the three RNA pols through common factors regulated by TOR and summarizes the most important similarities and differences between S. cerevisiae and mammals.
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Affiliation(s)
- Francisco Gutiérrez-Santiago
- Departamento de Biología Experimental-Genética, Universidad de Jaén, Paraje de las Lagunillas, s/n, E-23071 Jaén, Spain
| | - Francisco Navarro
- Departamento de Biología Experimental-Genética, Universidad de Jaén, Paraje de las Lagunillas, s/n, E-23071 Jaén, Spain
- Centro de Estudios Avanzados en Aceite de Oliva y Olivar, Universidad de Jaén, Paraje de las Lagunillas, s/n, E-23071 Jaén, Spain
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Teixeira V. Special Issue: Yeast Cell Signaling Pathways (Volume 1). Int J Mol Sci 2023; 24:ijms24054929. [PMID: 36902357 PMCID: PMC10003619 DOI: 10.3390/ijms24054929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 02/28/2023] [Indexed: 03/08/2023] Open
Abstract
This Special Issue was devoted to unravelling novel aspects of yeast biology and signal transduction in numerous yet intricate basic processes [...].
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Affiliation(s)
- Vitor Teixeira
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal;
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
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Inhibition of Ribosome Assembly and Ribosome Translation Has Distinctly Different Effects on Abundance and Paralogue Composition of Ribosomal Protein mRNAs in Saccharomyces cerevisiae. mSystems 2023; 8:e0109822. [PMID: 36651729 PMCID: PMC9948716 DOI: 10.1128/msystems.01098-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Many mutations in genes for ribosomal proteins (r-proteins) and assembly factors cause cell stress and altered cell fate, resulting in congenital diseases collectively called ribosomopathies. Even though all such mutations depress the cell's protein synthesis capacity, they generate many different phenotypes, suggesting that the diseases are not due simply to insufficient protein synthesis capacity. To learn more, we investigated how the global transcriptome in Saccharomyces cerevisiae responds to reduced protein synthesis generated in two different ways: abolishing the assembly of new ribosomes and inhibiting ribosomal function. Our results showed that the mechanism by which protein synthesis is obstructed affects the ribosomal protein transcriptome differentially: ribosomal protein mRNA abundance increases during the abolition of ribosome formation but decreases during the inhibition of ribosome function. Interestingly, the ratio between mRNAs from some, but not all, pairs of paralogous ribosomal protein genes encoding slightly different versions of a given r-protein changed differently during the two types of stress, suggesting that expression of specific ribosomal protein paralogous mRNAs may contribute to the stress response. Unexpectedly, the abundance of transcripts for ribosome assembly factors and translation factors remained relatively unaffected by the stresses. On the other hand, the state of the translation apparatus did affect cell physiology: mRNA levels for some other proteins not directly related to the translation apparatus also changed differentially, though not coordinately with the r-protein genes, in response to the stresses. IMPORTANCE Mutations in genes for ribosomal proteins or assembly factors cause a variety of diseases called ribosomopathies. These diseases are typically ascribed to a reduction in the cell's capacity for protein synthesis. Paradoxically, ribosomal mutations result in a wide variety of disease phenotypes, even though they all reduce protein synthesis. Here, we show that the transcriptome changes differently depending on how the protein synthesis capacity is reduced. Most strikingly, inhibiting ribosome formation and ribosome function had opposite effects on the abundance of mRNA for ribosomal proteins, while genes for ribosome translation and assembly factors showed no systematic responses. Thus, the process by which the protein synthesis capacity is reduced contributes decisively to global mRNA composition. This emphasis on process is a new concept in understanding ribosomopathies and other stress responses.
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Comparative Research: Regulatory Mechanisms of Ribosomal Gene Transcription in Saccharomyces cerevisiae and Schizosaccharomyces pombe. Biomolecules 2023; 13:biom13020288. [PMID: 36830657 PMCID: PMC9952952 DOI: 10.3390/biom13020288] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 01/31/2023] [Accepted: 02/01/2023] [Indexed: 02/05/2023] Open
Abstract
Restricting ribosome biosynthesis and assembly in response to nutrient starvation is a universal phenomenon that enables cells to survive with limited intracellular resources. When cells experience starvation, nutrient signaling pathways, such as the target of rapamycin (TOR) and protein kinase A (PKA), become quiescent, leading to several transcription factors and histone modification enzymes cooperatively and rapidly repressing ribosomal genes. Fission yeast has factors for heterochromatin formation similar to mammalian cells, such as H3K9 methyltransferase and HP1 protein, which are absent in budding yeast. However, limited studies on heterochromatinization in ribosomal genes have been conducted on fission yeast. Herein, we shed light on and compare the regulatory mechanisms of ribosomal gene transcription in two species with the latest insights.
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Jawed A, Ho CT, Grousl T, Shrivastava A, Ruppert T, Bukau B, Mogk A. Balanced activities of Hsp70 and the ubiquitin proteasome system underlie cellular protein homeostasis. Front Mol Biosci 2023; 9:1106477. [PMID: 36660429 PMCID: PMC9845930 DOI: 10.3389/fmolb.2022.1106477] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 12/15/2022] [Indexed: 01/05/2023] Open
Abstract
To counteract proteotoxic stress and cellular aging, protein quality control (PQC) systems rely on the refolding, degradation and sequestration of misfolded proteins. In Saccharomyces cerevisiae the Hsp70 chaperone system plays a central role in protein refolding, while degradation is predominantly executed by the ubiquitin proteasome system (UPS). The sequestrases Hsp42 and Btn2 deposit misfolded proteins in cytosolic and nuclear inclusions, thereby restricting the accessibility of misfolded proteins to Hsp70 and preventing the exhaustion of limited Hsp70 resources. Therefore, in yeast, sequestrase mutants show negative genetic interactions with double mutants lacking the Hsp70 co-chaperone Fes1 and the Hsp104 disaggregase (fes1Δ hsp104Δ, ΔΔ) and suffering from low Hsp70 capacity. Growth of ΔΔbtn2Δ mutants is highly temperature-sensitive and results in proteostasis breakdown at non-permissive temperatures. Here, we probed for the role of the ubiquitin proteasome system in maintaining protein homeostasis in ΔΔbtn2Δ cells, which are affected in two major protein quality control branches. We show that ΔΔbtn2Δ cells induce expression of diverse stress-related pathways including the ubiquitin proteasome system to counteract the proteostasis defects. Ubiquitin proteasome system dependent degradation of the stringent Hsp70 substrate firefly Luciferase in the mutant cells mirrors such compensatory activities of the protein quality control system. Surprisingly however, the enhanced ubiquitin proteasome system activity does not improve but aggravates the growth defects of ΔΔbtn2Δ cells. Reducing ubiquitin proteasome system activity in the mutant by lowering the levels of functional 26S proteasomes improved growth, increased refolding yield of the Luciferase reporter and attenuated global stress responses. Our findings indicate that an imbalance between Hsp70-dependent refolding, sequestration and ubiquitin proteasome system-mediated degradation activities strongly affects protein homeostasis of Hsp70 capacity mutants and contributes to their severe growth phenotypes.
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Affiliation(s)
- Areeb Jawed
- Center for Molecular Biology of Heidelberg University (ZMBH), University of Heidelberg, Heidelberg, Germany,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Chi-Ting Ho
- Center for Molecular Biology of Heidelberg University (ZMBH), University of Heidelberg, Heidelberg, Germany,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Tomas Grousl
- Center for Molecular Biology of Heidelberg University (ZMBH), University of Heidelberg, Heidelberg, Germany,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Aseem Shrivastava
- Center for Molecular Biology of Heidelberg University (ZMBH), University of Heidelberg, Heidelberg, Germany,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Thomas Ruppert
- Center for Molecular Biology of Heidelberg University (ZMBH), University of Heidelberg, Heidelberg, Germany
| | - Bernd Bukau
- Center for Molecular Biology of Heidelberg University (ZMBH), University of Heidelberg, Heidelberg, Germany,German Cancer Research Center (DKFZ), Heidelberg, Germany,*Correspondence: Axel Mogk, ; Bernd Bukau,
| | - Axel Mogk
- Center for Molecular Biology of Heidelberg University (ZMBH), University of Heidelberg, Heidelberg, Germany,German Cancer Research Center (DKFZ), Heidelberg, Germany,*Correspondence: Axel Mogk, ; Bernd Bukau,
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9
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Mameri A, Côté J. JAZF1: A metabolic actor subunit of the NuA4/TIP60 chromatin modifying complex. Front Cell Dev Biol 2023; 11:1134268. [PMID: 37091973 PMCID: PMC10119425 DOI: 10.3389/fcell.2023.1134268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 03/29/2023] [Indexed: 04/25/2023] Open
Abstract
The multisubunit NuA4/TIP60 complex is a lysine acetyltransferase, chromatin modifying factor and gene co-activator involved in diverse biological processes. The past decade has seen a growing appreciation for its role as a metabolic effector and modulator. However, molecular insights are scarce and often contradictory, underscoring the need for further mechanistic investigation. A particularly exciting route emerged with the recent identification of a novel subunit, JAZF1, which has been extensively linked to metabolic homeostasis. This review summarizes the major findings implicating NuA4/TIP60 in metabolism, especially in light of JAZF1 as part of the complex.
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10
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Xu X, Zhu F, Zhu Y, Li Y, Zhou H, Chen S, Ruan J. Transcriptome profiling of transcription factors in Ganoderma lucidum in response to methyl jasmonate. Front Microbiol 2022; 13:1052377. [PMID: 36504766 PMCID: PMC9730249 DOI: 10.3389/fmicb.2022.1052377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 10/31/2022] [Indexed: 11/25/2022] Open
Abstract
Ganoderma lucidum is a traditional Chinese medicine and its major active ingredients are ganoderma triterpenoids (GTs). To screen for transcription factors (TFs) that involved in the biosynthetic pathway of GTs in G. lucidum, the chemical composition in mycelia, primordium and fruiting body were analyzed, and the transcriptomes of mycelia induced by methyl jasmonate (MeJA) were analyzed. In addition, the expression level data of MeJA-responsive TFs in mycelia, primordia and fruiting body were downloaded from the database, and the correlation analysis was carried out between their expression profiles and the content of total triterpenoids. The results showed that a total of 89 components were identified, and the content of total triterpenoids was the highest in primordium, followed by fruiting body and mycelia. There were 103 differentially expressed TFs that response to MeJA-induction including 95 upregulated and 8 downregulated genes. These TFs were classified into 22 families including C2H2 (15), TFII-related (12), HTH (9), fungal (8), bZIP (6), HMG (5), DADS (2), etc. Correlation analysis showed that the expression level of GL23559 (MADS), GL26472 (HTH), and GL31187 (HMG) showed a positive correlation with the GTs content, respectively. While the expression level of GL25628 (fungal) and GL26980 (PHD) showed a negative correlation with the GTs content, respectively. Furthermore, the over expression of the Glmhr1 gene (GL25628) in Pichia pastoris GS115 indicated that it might be a negative regulator of GT biosynthesis through decreasing the production of lanosterol. This study provided useful information for a better understanding of the regulation of TFs involved in GT biosynthesis and fungal growth in G. lucidum.
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Affiliation(s)
- Xiaolan Xu
- College of Animal Sciences (College of Bee Science), Fujian Agriculture and Forestry University, Fuzhou, China
| | - Fengli Zhu
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yuxuan Zhu
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yujie Li
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Hao Zhou
- College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Shilin Chen
- Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China
- Institute of Herbgenomics, Chengdu University of Traditional Chinese Medicine, Chengdu, China
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11
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Guerra P, Vuillemenot LAPE, van Oppen YB, Been M, Milias-Argeitis A. TORC1 and PKA activity towards ribosome biogenesis oscillates in synchrony with the budding yeast cell cycle. J Cell Sci 2022; 135:276358. [PMID: 35975715 DOI: 10.1242/jcs.260378] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 07/11/2022] [Indexed: 10/15/2022] Open
Abstract
Recent studies have revealed that the growth rate of budding yeast and mammalian cells varies during the cell cycle. By linking a multitude of signals to cell growth, the highly conserved Target of Rapamycin Complex 1 (TORC1) and Protein Kinase A (PKA) pathways are prime candidates for mediating the dynamic coupling between growth and division. However, measurements of TORC1 and PKA activity during the cell cycle are still lacking. Following the localization dynamics of two TORC1 and PKA targets via time-lapse microscopy in hundreds of yeast cells, we found that the activity of these pathways towards ribosome biogenesis fluctuates in synchrony with the cell cycle even under constant external conditions. Mutations of upstream TORC1 and PKA regulators suggested that internal metabolic signals partially mediate these activity changes. Our study reveals a new aspect of TORC1 and PKA signaling, which will be important for understanding growth regulation during the cell cycle.
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Affiliation(s)
- Paolo Guerra
- Molecular Systems Biology, Groningen Biomolecular Sciences & Biotechnology Institute, University of Groningen, Netherlands
| | - Luc-Alban P E Vuillemenot
- Molecular Systems Biology, Groningen Biomolecular Sciences & Biotechnology Institute, University of Groningen, Netherlands
| | - Yulan B van Oppen
- Molecular Systems Biology, Groningen Biomolecular Sciences & Biotechnology Institute, University of Groningen, Netherlands
| | - Marije Been
- Molecular Systems Biology, Groningen Biomolecular Sciences & Biotechnology Institute, University of Groningen, Netherlands
| | - Andreas Milias-Argeitis
- Molecular Systems Biology, Groningen Biomolecular Sciences & Biotechnology Institute, University of Groningen, Netherlands
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12
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Pitfalls in using phenanthroline to study the causal relationship between promoter nucleosome acetylation and transcription. Nat Commun 2022; 13:3726. [PMID: 35768402 PMCID: PMC9242984 DOI: 10.1038/s41467-022-30350-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 04/21/2022] [Indexed: 11/10/2022] Open
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13
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Kumar S, Mashkoor M, Grove A. Yeast Crf1p: An activator in need is an activator indeed. Comput Struct Biotechnol J 2022; 20:107-116. [PMID: 34976315 PMCID: PMC8688861 DOI: 10.1016/j.csbj.2021.12.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 11/15/2021] [Accepted: 12/03/2021] [Indexed: 11/10/2022] Open
Abstract
Ribosome biogenesis is an energetically costly process, and tight regulation is required for stoichiometric balance between components. This requires coordination of RNA polymerases I, II, and III. Lack of nutrients or the presence of stress leads to downregulation of ribosome biogenesis, a process for which mechanistic target of rapamycin complex I (mTORC1) is key. mTORC1 activity is communicated by means of specific transcription factors, and in yeast, which is a primary model system in which transcriptional coordination has been delineated, transcription factors involved in regulation of ribosomal protein genes include Fhl1p and its cofactors, Ifh1p and Crf1p. Ifh1p is an activator, whereas Crf1p has been implicated in maintaining the repressed state upon mTORC1 inhibition. Computational analyses of evolutionary relationships have indicated that Ifh1p and Crf1p descend from a common ancestor. Here, we discuss recent evidence, which suggests that Crf1p also functions as an activator. We propose a model that consolidates available experimental evidence, which posits that Crf1p functions as an alternate activator to prevent the stronger activator Ifh1p from re-binding gene promoters upon mTORC1 inhibition. The correlation between retention of Crf1p in related yeast strains and duplication of ribosomal protein genes suggests that this backup activation may be important to ensure gene expression when Ifh1p is limiting. With ribosome biogenesis as a hallmark of cell growth, failure to control assembly of ribosomal components leads to several human pathologies. A comprehensive understanding of mechanisms underlying this process is therefore of the essence.
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Key Words
- CK2, casein kinase 2
- Crf1, corepressor with forkhead like
- Crf1p
- FHA, forkhead-associated
- FHB, forkhead-binding
- FKBP, FK506 binding protein
- Fhl1, forkhead like
- Fpr1, FK506-sensitive proline rotamase
- Gene regulation
- Hmo1, high mobility group
- Ifh1, interacts with forkhead like
- Ifh1p
- RASTR, ribosome assembly stress response
- RP, ribosomal protein
- Rap1, repressor/activator protein
- RiBi, ribosome biogenesis
- Ribosomal protein
- Ribosome biogenesis
- Sfp1, split finger protein
- WGD, whole genome duplication
- mTORC1
- mTORC1, mechanistic target of rapamycin complex 1
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Affiliation(s)
- Sanjay Kumar
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Muneera Mashkoor
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Anne Grove
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
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14
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Olivares-Yañez C, Sánchez E, Pérez-Lara G, Seguel A, Camejo PY, Larrondo LF, Vidal EA, Canessa P. A comprehensive transcription factor and DNA-binding motif resource for the construction of gene regulatory networks in Botrytis cinerea and Trichoderma atroviride. Comput Struct Biotechnol J 2021; 19:6212-6228. [PMID: 34900134 PMCID: PMC8637145 DOI: 10.1016/j.csbj.2021.11.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/11/2021] [Accepted: 11/11/2021] [Indexed: 11/25/2022] Open
Abstract
Botrytis cinerea and Trichoderma atroviride are two relevant fungi in agricultural systems. To gain insights into these organisms' transcriptional gene regulatory networks (GRNs), we generated a manually curated transcription factor (TF) dataset for each of them, followed by a GRN inference utilizing available sequence motifs describing DNA-binding specificity and global gene expression data. As a proof of concept of the usefulness of this resource to pinpoint key transcriptional regulators, we employed publicly available transcriptomics data and a newly generated dual RNA-seq dataset to build context-specific Botrytis and Trichoderma GRNs under two different biological paradigms: exposure to continuous light and Botrytis-Trichoderma confrontation assays. Network analysis of fungal responses to constant light revealed striking differences in the transcriptional landscape of both fungi. On the other hand, we found that the confrontation of both microorganisms elicited a distinct set of differentially expressed genes with changes in T. atroviride exceeding those in B. cinerea. Using our regulatory network data, we were able to determine, in both fungi, central TFs involved in this interaction response, including TFs controlling a large set of extracellular peptidases in the biocontrol agent T. atroviride. In summary, our work provides a comprehensive catalog of transcription factors and regulatory interactions for both organisms. This catalog can now serve as a basis for generating novel hypotheses on transcriptional regulatory circuits in different experimental contexts.
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Affiliation(s)
- Consuelo Olivares-Yañez
- ANID - Millennium Science Initiative Program - Millennium Institute for Integrative Biology (iBio), Avda. Libertador Bernardo O'Higgins 340, Santiago, Chile.,Centro de Biotecnologia Vegetal, Universidad Andres Bello, Republica 330, Santiago, Chile
| | - Evelyn Sánchez
- ANID - Millennium Science Initiative Program - Millennium Institute for Integrative Biology (iBio), Avda. Libertador Bernardo O'Higgins 340, Santiago, Chile.,Centro de Genomica y Bioinformatica, Facultad de Ciencias, Universidad Mayor, Camino la Pirámide 5750, Huechuraba, Santiago, Chile
| | - Gabriel Pérez-Lara
- ANID - Millennium Science Initiative Program - Millennium Institute for Integrative Biology (iBio), Avda. Libertador Bernardo O'Higgins 340, Santiago, Chile.,Centro de Biotecnologia Vegetal, Universidad Andres Bello, Republica 330, Santiago, Chile
| | - Aldo Seguel
- ANID - Millennium Science Initiative Program - Millennium Institute for Integrative Biology (iBio), Avda. Libertador Bernardo O'Higgins 340, Santiago, Chile.,Departamento de Genetica Molecular y Microbiologia, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Avda. Libertador Bernardo O'Higgins 340, Santiago, Chile
| | - Pamela Y Camejo
- ANID - Millennium Science Initiative Program - Millennium Institute for Integrative Biology (iBio), Avda. Libertador Bernardo O'Higgins 340, Santiago, Chile
| | - Luis F Larrondo
- ANID - Millennium Science Initiative Program - Millennium Institute for Integrative Biology (iBio), Avda. Libertador Bernardo O'Higgins 340, Santiago, Chile.,Departamento de Genetica Molecular y Microbiologia, Facultad de Ciencias Biologicas, Pontificia Universidad Catolica de Chile, Avda. Libertador Bernardo O'Higgins 340, Santiago, Chile
| | - Elena A Vidal
- ANID - Millennium Science Initiative Program - Millennium Institute for Integrative Biology (iBio), Avda. Libertador Bernardo O'Higgins 340, Santiago, Chile.,Centro de Genomica y Bioinformatica, Facultad de Ciencias, Universidad Mayor, Camino la Pirámide 5750, Huechuraba, Santiago, Chile.,Escuela de Biotecnologia, Facultad de Ciencias, Universidad Mayor, Camino la Pirámide 5750, Huechuraba, Santiago, Chile
| | - Paulo Canessa
- ANID - Millennium Science Initiative Program - Millennium Institute for Integrative Biology (iBio), Avda. Libertador Bernardo O'Higgins 340, Santiago, Chile.,Centro de Biotecnologia Vegetal, Universidad Andres Bello, Republica 330, Santiago, Chile
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15
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Li L, Zhu T, Song Y, Luo X, Datla R, Ren M. Target of rapamycin controls hyphal growth and pathogenicity through FoTIP4 in Fusarium oxysporum. MOLECULAR PLANT PATHOLOGY 2021; 22:1239-1255. [PMID: 34288333 PMCID: PMC8435236 DOI: 10.1111/mpp.13108] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/21/2021] [Accepted: 06/22/2021] [Indexed: 05/07/2023]
Abstract
Fusarium oxysporum is the causal agent of the devastating Fusarium wilt by invading and colonizing the vascular system in various plants, resulting in substantial economic losses worldwide. Target of rapamycin (TOR) is a central regulator that controls intracellular metabolism, cell growth, and stress responses in eukaryotes, but little is known about TOR signalling in F. oxysporum. In this study, we identified conserved FoTOR signalling pathway components including FoTORC1 and FoTORC2. Pharmacological assays showed that F. oxysporum is hypersensitive to rapamycin in the presence of FoFKBP12 while the deletion mutant strain ΔFofkbp12 is insensitive to rapamycin. Transcriptomic data indicated that FoTOR signalling controls multiple metabolic processes including ribosome biogenesis and cell wall-degrading enzymes (CWDEs). Genetic analysis revealed that FoTOR1 interacting protein 4 (FoTIP4) acts as a new component of FoTOR signalling to regulate hyphal growth and pathogenicity of F. oxysporum. Importantly, transcript levels of genes associated with ribosome biogenesis and CWDEs were dramatically downregulated in the ΔFotip4 mutant strain. Electrophoretic mobility shift assays showed that FoTIP4 can bind to the promoters of ribosome biogenesis- and CWDE-related genes to positively regulate the expression of these genes. These results suggest that FoTOR signalling plays central roles in regulating hyphal growth and pathogenicity of F. oxysporum and provide new insights into FoTOR1 as a target for controlling and preventing Fusarium wilt in plants.
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Affiliation(s)
- Linxuan Li
- Institute of Urban AgricultureChinese Academy of Agricultural SciencesChengdu National Agricultural Science and Technology CenterChengduChina
| | - Tingting Zhu
- Institute of Urban AgricultureChinese Academy of Agricultural SciencesChengdu National Agricultural Science and Technology CenterChengduChina
| | - Yun Song
- Zhengzhou Research BaseState Key Laboratory of Cotton BiologyZhengzhou UniversityZhengzhouChina
- School of Life SciencesLiaocheng UniversityLiaochengChina
| | - Xiumei Luo
- Institute of Urban AgricultureChinese Academy of Agricultural SciencesChengdu National Agricultural Science and Technology CenterChengduChina
| | - Raju Datla
- Global Institute for Food Security in SaskatoonUniversity of SaskatchewanSaskatoonCanada
| | - Maozhi Ren
- Institute of Urban AgricultureChinese Academy of Agricultural SciencesChengdu National Agricultural Science and Technology CenterChengduChina
- Zhengzhou Research BaseState Key Laboratory of Cotton BiologyZhengzhou UniversityZhengzhouChina
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16
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Rico-Díaz A, Barreiro-Alonso A, Rey-Souto C, Becerra M, Lamas-Maceiras M, Cerdán ME, Vizoso-Vázquez Á. The HMGB Protein KlIxr1, a DNA Binding Regulator of Kluyveromyces lactis Gene Expression Involved in Oxidative Metabolism, Growth, and dNTP Synthesis. Biomolecules 2021; 11:biom11091392. [PMID: 34572607 PMCID: PMC8465852 DOI: 10.3390/biom11091392] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 09/10/2021] [Accepted: 09/16/2021] [Indexed: 12/15/2022] Open
Abstract
In the traditional fermentative model yeast Saccharomyces cerevisiae, ScIxr1 is an HMGB (High Mobility Group box B) protein that has been considered as an important regulator of gene transcription in response to external changes like oxygen, carbon source, or nutrient availability. Kluyveromyces lactis is also a useful eukaryotic model, more similar to many human cells due to its respiratory metabolism. We cloned and functionally characterized by different methodologies KlIXR1, which encodes a protein with only 34.4% amino acid sequence similarity to ScIxr1. Our data indicate that both proteins share common functions, including their involvement in the response to hypoxia or oxidative stress induced by hydrogen peroxide or metal treatments, as well as in the control of key regulators for maintenance of the dNTP (deoxyribonucleotide triphosphate) pool and ribosome synthesis. KlIxr1 is able to bind specific regulatory DNA sequences in the promoter of its target genes, which are well conserved between S. cerevisiae and K. lactis. Oppositely, we found important differences between ScIrx1 and KlIxr1 affecting cellular responses to cisplatin or cycloheximide in these yeasts, which could be dependent on specific and non-conserved domains present in these two proteins.
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17
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Yahya G, Hashem Mohamed N, Pijuan J, Seleem NM, Mosbah R, Hess S, Abdelmoaty AA, Almeer R, Abdel‐Daim MM, Shulaywih Alshaman H, Juraiby I, Metwally K, Storchova Z. Profiling the physiological pitfalls of anti-hepatitis C direct-acting agents in budding yeast. Microb Biotechnol 2021; 14:2199-2213. [PMID: 34378349 PMCID: PMC8449668 DOI: 10.1111/1751-7915.13904] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 07/16/2021] [Accepted: 07/17/2021] [Indexed: 02/05/2023] Open
Abstract
Sofosbuvir and Daclatasvir are among the direct-acting antiviral (DAA) medications prescribed for the treatment of chronic hepatitis C (CHC) virus infection as combination therapy with other antiviral medications. DAA-based therapy achieves high cure rates, reaching up to 97% depending on the genotype of the causative hepatitis C virus (HCV). While DAAs have been approved as an efficient and well-tolerated therapy for CHC, emerging concerns about adverse cardiac side effects, higher risk of recurrence and occurrence of hepatocellular carcinoma (HCC) and doubts of genotoxicity have been reported. In our study, we investigated in detail physiological off-targets of DAAs and dissected the effects of these drugs on cellular organelles using budding yeast, a unicellular eukaryotic organism. DAAs were found to disturb the architecture of the endoplasmic reticulum (ER) and the mitochondria, while showing no apparent genotoxicity or DNA damaging effect. Our study provides evidence that DAAs are not associated with genotoxicity and highlights the necessity for adjunctive antioxidant therapy to mitigate the adverse effects of DAAs on ER and mitochondria.
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Affiliation(s)
- Galal Yahya
- Department of Microbiology and ImmunologyFaculty of PharmacyZagazig UniversityAl Sharqia44519Egypt
- Department of Molecular GeneticsFaculty of BiologyTechnical University of KaiserslauternPaul‐Ehrlich Str. 24Kaiserslautern67663Germany
| | | | - Jordi Pijuan
- Laboratory of Neurogenetics and Molecular Medicine ‐ IPERInstitut de Recerca Sant Joan de DéuBarcelona08950Spain
| | - Noura M. Seleem
- Department of Microbiology and ImmunologyFaculty of PharmacyZagazig UniversityAl Sharqia44519Egypt
| | - Rasha Mosbah
- Infection Control UnitHospitals of Zagazig UniversityAl SharqiaEgypt
| | - Steffen Hess
- Department of Cell BiologyFaculty of BiologyTechnical University of KaiserslauternKaiserslauternGermany
| | - Ahmed A. Abdelmoaty
- Department of Tropical MedicineFaculty of MedicineZagazig UniversityZagazig44519Egypt
| | - Rafa Almeer
- Department of ZoologyCollege of ScienceKing Saud UniversityP.O. Box 2455Riyadh11451Saudi Arabia
| | - Mohamed M. Abdel‐Daim
- Department of ZoologyCollege of ScienceKing Saud UniversityP.O. Box 2455Riyadh11451Saudi Arabia
- Pharmacology DepartmentCollege of Veterinary MedicineSuez Canal UniversityIsmailiaEgypt
| | | | - Ibrahim Juraiby
- General Directorate of Health AffairsMinistry of HealthJazan82723Saudi Arabia
| | - Kamel Metwally
- Department of Pharmaceutical ChemistryFaculty of PharmacyTabuk UniversityTabuk47713Saudi Arabia
- Department of Medicinal ChemistryFaculty of PharmacyZagazig UniversityZagazig44519Egypt
| | - Zuzana Storchova
- Department of Molecular GeneticsFaculty of BiologyTechnical University of KaiserslauternPaul‐Ehrlich Str. 24Kaiserslautern67663Germany
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18
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Teixeira V, Martins TS, Prinz WA, Costa V. Target of Rapamycin Complex 1 (TORC1), Protein Kinase A (PKA) and Cytosolic pH Regulate a Transcriptional Circuit for Lipid Droplet Formation. Int J Mol Sci 2021; 22:9017. [PMID: 34445723 PMCID: PMC8396576 DOI: 10.3390/ijms22169017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/12/2021] [Accepted: 08/19/2021] [Indexed: 11/16/2022] Open
Abstract
Lipid droplets (LDs) are ubiquitous organelles that fulfill essential roles in response to metabolic cues. The identification of several neutral lipid synthesizing and regulatory protein complexes have propelled significant advance on the mechanisms of LD biogenesis in the endoplasmic reticulum (ER). However, our understanding of signaling networks, especially transcriptional mechanisms, regulating membrane biogenesis is very limited. Here, we show that the nutrient-sensing Target of Rapamycin Complex 1 (TORC1) regulates LD formation at a transcriptional level, by targeting DGA1 expression, in a Sit4-, Mks1-, and Sfp1-dependent manner. We show that cytosolic pH (pHc), co-regulated by the plasma membrane H+-ATPase Pma1 and the vacuolar ATPase (V-ATPase), acts as a second messenger, upstream of protein kinase A (PKA), to adjust the localization and activity of the major transcription factor repressor Opi1, which in turn controls the metabolic switch between phospholipid metabolism and lipid storage. Together, this work delineates hitherto unknown molecular mechanisms that couple nutrient availability and pHc to LD formation through a transcriptional circuit regulated by major signaling transduction pathways.
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Affiliation(s)
- Vitor Teixeira
- Yeast Signalling Networks, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (T.S.M.); (V.C.)
- Yeast Signalling Networks, IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
| | - Telma S. Martins
- Yeast Signalling Networks, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (T.S.M.); (V.C.)
- Yeast Signalling Networks, IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
- ICBAS—Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal
| | - William A. Prinz
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA;
| | - Vítor Costa
- Yeast Signalling Networks, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (T.S.M.); (V.C.)
- Yeast Signalling Networks, IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
- ICBAS—Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal
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19
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Li Y, Sun A, Wu Q, Zou X, Chen F, Cai R, Xie H, Zhang M, Guo X. Comprehensive genomic survey, structural classification and expression analysis of C 2H 2-type zinc finger factor in wheat (Triticum aestivum L.). BMC PLANT BIOLOGY 2021; 21:380. [PMID: 34407757 PMCID: PMC8375173 DOI: 10.1186/s12870-021-03016-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 05/06/2021] [Indexed: 06/04/2023]
Abstract
BACKGROUND The C2H2-type zinc finger proteins (C2H2-ZFPs) are one of major classes of transcription factors that play important roles in plant growth, development and stress responses. Limit information about the C2H2-ZF genes hinders the molecular breeding in bread wheat (Triticum aestivum). RESULTS In this study, 457 C2H2-ZFP proteins (including 253 splice variants), which contain four types of conserved domain (named Q, M, Z, and D), could be further classified into ten subsets. They were identified to be distributed in 21 chromosomes in T. aestivum. Subset-specific motifs, like NPL-, SFP1-, DL- (EAR-like-motif), R-, PL-, L- and EK-, might make C2H2-ZFP diverse multifunction. Interestingly, NPL- and SFP1-box were firstly found to be located in C2H2-ZFP proteins. Synteny analyses showed that only 4 pairs of C2H2 family genes in T. aestivum, 65 genes in B. distachyon, 66 genes in A. tauschii, 68 genes in rice, 9 genes in Arabidopsis, were syntenic relationships respectively. It indicated that TaZFPs were closely related to genes in Poaceae. From the published transcriptome data, totally 198 of 204 TaC2H2-ZF genes have expression data. Among them, 25 TaC2H2-ZF genes were certificated to be significantly differentially expressed in 5 different organs and 15 different development stages by quantitative RT-PCR. The 18 TaC2H2-ZF genes were verified in response to heat, drought, and heat & drought stresses. According to expression pattern analysis, several TaZFPs, like Traes_5BL_D53A846BE.1, were not only highly expressed in L2DAAs, RTLS, RMS, but also endowed tolerance to drought and heat stresses, making them good candidates for molecular breeding. CONCLUSIONS This study systematically characterized the TaC2H2-ZFPs and their potential roles in T. aestivum. Our findings provide new insights into the C2H2-ZF genes in T. aestivum as well as a foundation for further studies on the roles of TaC2H2-ZF genes in T. aestivum molecular breeding.
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Affiliation(s)
- Yongliang Li
- College of Biology, Hunan University, Changsha, 410082, China
| | - Aolong Sun
- College of Biology, Hunan University, Changsha, 410082, China
| | - Qun Wu
- College of Biology, Hunan University, Changsha, 410082, China
| | - Xiaoxiao Zou
- College of Biology, Hunan University, Changsha, 410082, China
| | - Fenglin Chen
- College of Biology, Hunan University, Changsha, 410082, China
| | - Ruqiong Cai
- College of Biology, Hunan University, Changsha, 410082, China
| | - Hai Xie
- College of Biology, Hunan University, Changsha, 410082, China
| | - Meng Zhang
- College of Biology, Hunan University, Changsha, 410082, China.
| | - Xinhong Guo
- College of Biology, Hunan University, Changsha, 410082, China.
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20
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Transcriptional control of ribosome biogenesis in yeast: links to growth and stress signals. Biochem Soc Trans 2021; 49:1589-1599. [PMID: 34240738 PMCID: PMC8421047 DOI: 10.1042/bst20201136] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/14/2021] [Accepted: 06/18/2021] [Indexed: 12/15/2022]
Abstract
Ribosome biogenesis requires prodigious transcriptional output in rapidly growing yeast cells and is highly regulated in response to both growth and stress signals. This minireview focuses on recent developments in our understanding of this regulatory process, with an emphasis on the 138 ribosomal protein genes (RPGs) themselves and a group of >200 ribosome biogenesis (RiBi) genes whose products contribute to assembly but are not part of the ribosome. Expression of most RPGs depends upon Rap1, a pioneer transcription factor (TF) required for the binding of a pair of RPG-specific TFs called Fhl1 and Ifh1. RPG expression is correlated with Ifh1 promoter binding, whereas Rap1 and Fhl1 remain promoter-associated upon stress-induced down regulation. A TF called Sfp1 has also been implicated in RPG regulation, though recent work reveals that its primary function is in activation of RiBi and other growth-related genes. Sfp1 plays an important regulatory role at a small number of RPGs where Rap1–Fhl1–Ifh1 action is subsidiary or non-existent. In addition, nearly half of all RPGs are bound by Hmo1, which either stabilizes or re-configures Fhl1–Ifh1 binding. Recent studies identified the proline rotamase Fpr1, known primarily for its role in rapamycin-mediated inhibition of the TORC1 kinase, as an additional TF at RPG promoters. Fpr1 also affects Fhl1–Ifh1 binding, either independently or in cooperation with Hmo1. Finally, a major recent development was the discovery of a protein homeostasis mechanism driven by unassembled ribosomal proteins, referred to as the Ribosome Assembly Stress Response (RASTR), that controls RPG transcription through the reversible condensation of Ifh1.
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21
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Kobiita A, Godbersen S, Araldi E, Ghoshdastider U, Schmid MW, Spinas G, Moch H, Stoffel M. The Diabetes Gene JAZF1 Is Essential for the Homeostatic Control of Ribosome Biogenesis and Function in Metabolic Stress. Cell Rep 2021; 32:107846. [PMID: 32640216 DOI: 10.1016/j.celrep.2020.107846] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 04/23/2020] [Accepted: 06/11/2020] [Indexed: 02/07/2023] Open
Abstract
The ability of pancreatic β-cells to respond to increased demands for insulin during metabolic stress critically depends on proper ribosome homeostasis and function. Excessive and long-lasting stimulation of insulin secretion can elicit endoplasmic reticulum (ER) stress, unfolded protein response, and β-cell apoptosis. Here we show that the diabetes susceptibility gene JAZF1 is a key transcriptional regulator of ribosome biogenesis, global protein, and insulin translation. JAZF1 is excluded from the nucleus, and its expression levels are reduced upon metabolic stress and in diabetes. Genetic deletion of Jazf1 results in global impairment of protein synthesis that is mediated by defects in ribosomal protein synthesis, ribosomal RNA processing, and aminoacyl-synthetase expression, thereby inducing ER stress and increasing β-cell susceptibility to apoptosis. Importantly, JAZF1 function and its pleiotropic actions are impaired in islets of murine T2D and in human islets exposed to metabolic stress. Our study identifies JAZF1 as a central mediator of metabolic stress in β-cells.
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Affiliation(s)
- Ahmad Kobiita
- Institute of Molecular Health Sciences, ETH Zurich, Otto-Stern-Weg 7, HPL H36, 8093 Zürich, Switzerland
| | - Svenja Godbersen
- Institute of Molecular Health Sciences, ETH Zurich, Otto-Stern-Weg 7, HPL H36, 8093 Zürich, Switzerland
| | - Elisa Araldi
- Institute of Molecular Health Sciences, ETH Zurich, Otto-Stern-Weg 7, HPL H36, 8093 Zürich, Switzerland
| | - Umesh Ghoshdastider
- Institute of Molecular Health Sciences, ETH Zurich, Otto-Stern-Weg 7, HPL H36, 8093 Zürich, Switzerland
| | - Marc W Schmid
- MWSchmid GmbH, Möhrlistrasse 25, 8006 Zurich, Switzerland
| | - Giatgen Spinas
- Klinik für Endokrinologie, Diabetologie und Klinische Ernährung, Universitäts-Spital Zürich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - Holger Moch
- Department of Pathology and Molecular Pathology, University and University Hospital Zürich, Schmelzbergstrasse 12, 8091 Zürich, Switzerland
| | - Markus Stoffel
- Institute of Molecular Health Sciences, ETH Zurich, Otto-Stern-Weg 7, HPL H36, 8093 Zürich, Switzerland; Medical Faculty, University of Zurich, Zurich, Switzerland.
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22
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Abstract
Blood is generated throughout life by continued proliferation and differentiation of hematopoietic progenitors, while at the top of the hierarchy, hematopoietic stem cells (HSCs) remain largely quiescent. This way HSCs avoid senescence and preserve their capacity to repopulate the hematopoietic system. But HSCs are not always quiescent, proliferating extensively in conditions such as those found in the fetal liver. Understanding the elusive mechanisms that regulate HSC fate would enable us to comprehend a crucial piece of HSC biology and pave the way for ex-vivo HSC expansion with clear clinical benefit. Here we review how metabolism, endoplasmic reticulum stress and oxidative stress condition impact HSCs decision to self-renew or differentiate and how these signals integrate into the mammalian target of rapamycin (mTOR) pathway. We argue that the bone marrow microenvironment continuously favors differentiation through the activation of the mTOR complex (mTORC)1 signaling, while the fetal liver microenvironment favors self-renewal through the inverse mechanism. In addition, we also postulate that strategies that have successfully achieved HSC expansion, directly or indirectly, lead to the inactivation of mTORC1. Finally, we propose a mechanism by which mTOR signaling, during cell division, conditions HSC fate. This mechanism has already been demonstrated in mature hematopoietic cells (T-cells), that face a similar decision after activation, either undergoing clonal expansion or differentiation.
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23
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Saleh MM, Tourigny JP, Zentner GE. Genome-Wide Profiling of Protein-DNA Interactions with Chromatin Endogenous Cleavage and High-Throughput Sequencing (ChEC-Seq ). Methods Mol Biol 2021; 2351:289-303. [PMID: 34382196 DOI: 10.1007/978-1-0716-1597-3_16] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Interactions between regulatory proteins and specific genomic regions are critical for all chromatin-based processes, including transcription, DNA replication, and DNA repair. Genome-wide mapping of such interactions is most commonly performed with chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-Seq), but a number of orthogonal methods employing targeted enzymatic activity have also been introduced. We previously described a genome-wide implementation of chromatin endogenous cleavage (ChEC-Seq), wherein a protein of interest is fused to micrococcal nuclease (MNase) to enable targeted, calcium-dependent genomic cleavage. Here, we describe the ChEC-Seq protocol for use in budding yeast though it can be used in other organisms in conjunction with appropriate methods for introduction of an MNase fusion protein.
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Affiliation(s)
| | | | - Gabriel E Zentner
- Department of Biology, Indiana University, Bloomington, IN, USA.
- Indiana University Melvin and Bren Simon Comprehensive Cancer Center, Indianapolis, IN, USA.
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24
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Zencir S, Dilg D, Rueda MP, Shore D, Albert B. Mechanisms coordinating ribosomal protein gene transcription in response to stress. Nucleic Acids Res 2020; 48:11408-11420. [PMID: 33084907 PMCID: PMC7672434 DOI: 10.1093/nar/gkaa852] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/17/2020] [Accepted: 10/11/2020] [Indexed: 11/14/2022] Open
Abstract
While expression of ribosomal protein genes (RPGs) in the budding yeast has been extensively studied, a longstanding enigma persists regarding their co-regulation under fluctuating growth conditions. Most RPG promoters display one of two distinct arrangements of a core set of transcription factors (TFs) and are further differentiated by the presence or absence of the HMGB protein Hmo1. However, a third group of promoters appears not to be bound by any of these proteins, raising the question of how the whole suite of genes is co-regulated. We demonstrate here that all RPGs are regulated by two distinct, but complementary mechanisms driven by the TFs Ifh1 and Sfp1, both of which are required for maximal expression in optimal conditions and coordinated downregulation upon stress. At the majority of RPG promoters, Ifh1-dependent regulation predominates, whereas Sfp1 plays the major role at all other genes. We also uncovered an unexpected protein homeostasis-dependent binding property of Hmo1 at RPG promoters. Finally, we show that the Ifh1 paralog Crf1, previously described as a transcriptional repressor, can act as a constitutive RPG activator. Our study provides a more complete picture of RPG regulation and may serve as a paradigm for unravelling RPG regulation in multicellular eukaryotes.
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Affiliation(s)
- Sevil Zencir
- Department of Molecular Biology and Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Daniel Dilg
- Department of Molecular Biology and Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Maria Paula Rueda
- Department of Molecular Biology and Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - David Shore
- Department of Molecular Biology and Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
| | - Benjamin Albert
- Department of Molecular Biology and Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, 30 quai Ernest-Ansermet, 1211 Geneva 4, Switzerland
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25
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Abstract
To persist in their dynamic human host environments, fungal pathogens must sense and adapt by modulating their gene expression to fulfill their cellular needs. Understanding transcriptional regulation on a global scale would uncover cellular processes linked to persistence and virulence mechanisms that could be targeted for antifungal therapeutics. Infections associated with the yeast Candida albicans, a highly prevalent fungal pathogen, and the multiresistant related species Candida auris are becoming a serious public health threat. To define the set of a gene regulated by a transcriptional regulator in C. albicans, chromatin immunoprecipitation (ChIP)-based techniques, including ChIP with microarray technology (ChIP-chip) or ChIP-DNA sequencing (ChIP-seq), have been widely used. Here, we describe a new set of PCR-based micrococcal nuclease (MNase)-tagging plasmids for C. albicans and other Candida spp. to determine the genome-wide location of any transcriptional regulator of interest using chromatin endogenous cleavage (ChEC) coupled to high-throughput sequencing (ChEC-seq). The ChEC procedure does not require protein-DNA cross-linking or sonication, thus avoiding artifacts related to epitope masking or the hyper-ChIPable euchromatic phenomenon. In a proof-of-concept application of ChEC-seq, we provided a high-resolution binding map of the SWI/SNF chromatin remodeling complex, a master regulator of fungal fitness in C. albicans, in addition to the transcription factor Nsi1 that is an ortholog of the DNA-binding protein Reb1 for which genome-wide occupancy was previously established in Saccharomyces cerevisiae The ChEC-seq procedure described here will allow a high-resolution genomic location definition which will enable a better understanding of transcriptional regulatory circuits that govern fungal fitness and drug resistance in these medically important fungi.IMPORTANCE Systemic fungal infections caused by Candida albicans and the "superbug" Candida auris are becoming a serious public health threat. The ability of these yeasts to cause disease is linked to their faculty to modulate the expression of genes that mediate their escape from the immune surveillance and their persistence in the different unfavorable niches within the host. Comprehensive knowledge on gene expression control of fungal fitness is consequently an interesting framework for the identification of essential infection processes that could be hindered by chemicals as potential therapeutics. Here, we expanded the use of ChEC-seq, a technique that was initially developed in the yeast model Saccharomyces cerevisiae to identify genes that are modulated by a transcriptional regulator, in pathogenic yeasts from the genus Candida This robust technique will allow a better characterization of key gene expression regulators and their contribution to virulence and antifungal resistance in these pathogenic yeasts.
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26
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Knoll ER, Zhu ZI, Sarkar D, Landsman D, Morse RH. Kin28 depletion increases association of TFIID subunits Taf1 and Taf4 with promoters in Saccharomyces cerevisiae. Nucleic Acids Res 2020; 48:4244-4255. [PMID: 32182349 DOI: 10.1093/nar/gkaa165] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 02/07/2020] [Accepted: 03/04/2020] [Indexed: 01/31/2023] Open
Abstract
Transcription of eukaryotic mRNA-encoding genes by RNA polymerase II (Pol II) begins with assembly of the pre-initiation complex (PIC), comprising Pol II and the general transcription factors. Although the pathway of PIC assembly is well established, the mechanism of assembly and the dynamics of PIC components are not fully understood. For example, only recently has it been shown that in yeast, the Mediator complex normally occupies promoters only transiently, but shows increased association when Pol II promoter escape is inhibited. Here we show that two subunits of TFIID, Taf1 and Taf4, similarly show increased occupancy as measured by ChIP upon depletion or inactivation of Kin28. In contrast, TBP occupancy is unaffected by depletion of Kin28, thus revealing an uncoupling of Taf and TBP occupancy during the transcription cycle. Increased Taf1 occupancy upon Kin28 depletion is suppressed by depletion of TBP, while depletion of TBP in the presence of Kin28 has little effect on Taf1 occupancy. The increase in Taf occupancy upon depletion of Kin28 is more pronounced at TFIID-dominated promoters compared to SAGA-dominated promoters. Our results support the suggestion, based on recent structural studies, that TFIID may not remain bound to gene promoters through the transcription initiation cycle.
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Affiliation(s)
- Elisabeth R Knoll
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, NY 12201-0509, USA
| | - Z Iris Zhu
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, NIH, Bethesda, MD 20814, USA
| | - Debasish Sarkar
- Wadsworth Center, New York State Department of Health, Albany, NY 12201-0509, USA
| | - David Landsman
- Computational Biology Branch, National Center for Biotechnology Information, National Library of Medicine, NIH, Bethesda, MD 20814, USA
| | - Randall H Morse
- Department of Biomedical Sciences, University at Albany School of Public Health, Albany, NY 12201-0509, USA.,Wadsworth Center, New York State Department of Health, Albany, NY 12201-0509, USA
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27
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Kunkel J, Luo X, Capaldi AP. Integrated TORC1 and PKA signaling control the temporal activation of glucose-induced gene expression in yeast. Nat Commun 2019; 10:3558. [PMID: 31395866 PMCID: PMC6687784 DOI: 10.1038/s41467-019-11540-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 07/19/2019] [Indexed: 01/04/2023] Open
Abstract
The growth rate of a yeast cell is controlled by the target of rapamycin kinase complex I (TORC1) and cAMP-dependent protein kinase (PKA) pathways. To determine how TORC1 and PKA cooperate to regulate cell growth, we performed temporal analysis of gene expression in yeast switched from a non-fermentable substrate, to glucose, in the presence and absence of TORC1 and PKA inhibitors. Quantitative analysis of these data reveals that PKA drives the expression of key cell growth genes during transitions into, and out of, the rapid growth state in glucose, while TORC1 is important for the steady-state expression of the same genes. This circuit design may enable yeast to set an exact growth rate based on the abundance of internal metabolites such as amino acids, via TORC1, but also adapt rapidly to changes in external nutrients, such as glucose, via PKA.
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Affiliation(s)
- Joseph Kunkel
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, 85721-0206, USA
| | - Xiangxia Luo
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, 85721-0206, USA
| | - Andrew P Capaldi
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, 85721-0206, USA.
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28
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Parnell EJ, Stillman DJ. Multiple Negative Regulators Restrict Recruitment of the SWI/SNF Chromatin Remodeler to the HO Promoter in Saccharomyces cerevisiae. Genetics 2019; 212:1181-1204. [PMID: 31167839 PMCID: PMC6707452 DOI: 10.1534/genetics.119.302359] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 05/30/2019] [Indexed: 01/22/2023] Open
Abstract
Activation of the Saccharomyces cerevisiae HO promoter is highly regulated, requiring the ordered recruitment of activators and coactivators and allowing production of only a few transcripts in mother cells within a short cell cycle window. We conducted genetic screens to identify the negative regulators of HO expression necessary to limit HO transcription. Known repressors of HO (Ash1 and Rpd3) were identified, as well as several additional chromatin-associated factors including the Hda1 histone deacetylase, the Isw2 chromatin remodeler, and the corepressor Tup1 We also identified clusters of HO promoter mutations that suggested roles for the Dot6/Tod6 (PAC site) and Ume6 repression pathways. We used ChIP assays with synchronized cells to validate the involvement of these factors and map the association of Ash1, Dot6, and Ume6 with the HO promoter to a brief window in the cell cycle between binding of the initial activating transcription factor and initiation of transcription. We found that Ash1 and Ume6 each recruit the Rpd3 histone deacetylase to HO, and their effects are additive. In contrast, Rpd3 was not recruited significantly to the PAC site, suggesting this site has a distinct mechanism for repression. Increases in HO expression and SWI/SNF recruitment were all additive upon loss of Ash1, Ume6, and PAC site factors, indicating the convergence of independent pathways for repression. Our results demonstrate that multiple protein complexes are important for limiting the spread of SWI/SNF-mediated nucleosome eviction across the HO promoter, suggesting that regulation requires a delicate balance of activities that promote and repress transcription.
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Affiliation(s)
- Emily J Parnell
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, Utah 84112
| | - David J Stillman
- Department of Pathology, University of Utah Health Sciences Center, Salt Lake City, Utah 84112
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29
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Matos-Perdomo E, Machín F. Nucleolar and Ribosomal DNA Structure under Stress: Yeast Lessons for Aging and Cancer. Cells 2019; 8:cells8080779. [PMID: 31357498 PMCID: PMC6721496 DOI: 10.3390/cells8080779] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 07/15/2019] [Accepted: 07/24/2019] [Indexed: 02/06/2023] Open
Abstract
Once thought a mere ribosome factory, the nucleolus has been viewed in recent years as an extremely sensitive gauge of diverse cellular stresses. Emerging concepts in nucleolar biology include the nucleolar stress response (NSR), whereby a series of cell insults have a special impact on the nucleolus. These insults include, among others, ultra-violet radiation (UV), nutrient deprivation, hypoxia and thermal stress. While these stresses might influence nucleolar biology directly or indirectly, other perturbances whose origin resides in the nucleolar biology also trigger nucleolar and systemic stress responses. Among the latter, we find mutations in nucleolar and ribosomal proteins, ribosomal RNA (rRNA) processing inhibitors and ribosomal DNA (rDNA) transcription inhibition. The p53 protein also mediates NSR, leading ultimately to cell cycle arrest, apoptosis, senescence or differentiation. Hence, NSR is gaining importance in cancer biology. The nucleolar size and ribosome biogenesis, and how they connect with the Target of Rapamycin (TOR) signalling pathway, are also becoming important in the biology of aging and cancer. Simple model organisms like the budding yeast Saccharomyces cerevisiae, easy to manipulate genetically, are useful in order to study nucleolar and rDNA structure and their relationship with stress. In this review, we summarize the most important findings related to this topic.
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Affiliation(s)
- Emiliano Matos-Perdomo
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, 38010 Santa Cruz de Tenerife, Spain
- Escuela de Doctorado y Estudios de Postgrado, Universidad de La Laguna, 38200 Tenerife, Spain
| | - Félix Machín
- Unidad de Investigación, Hospital Universitario Nuestra Señora de Candelaria, 38010 Santa Cruz de Tenerife, Spain.
- Instituto de Tecnologías Biomédicas, Universidad de La Laguna, 38200 Tenerife, Spain.
- Facultad de Ciencias de la Salud, Universidad Fernando Pessoa Canarias, 35450 Santa María de Guía, Gran Canaria, Spain.
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30
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Homotypic cooperativity and collective binding are determinants of bHLH specificity and function. Proc Natl Acad Sci U S A 2019; 116:16143-16152. [PMID: 31341088 DOI: 10.1073/pnas.1818015116] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Eukaryotic cells express transcription factor (TF) paralogues that bind to nearly identical DNA sequences in vitro but bind at different genomic loci and perform different functions in vivo. Predicting how 2 paralogous TFs bind in vivo using DNA sequence alone is an important open problem. Here, we analyzed 2 yeast bHLH TFs, Cbf1p and Tye7p, which have highly similar binding preferences in vitro, yet bind at almost completely nonoverlapping target loci in vivo. We dissected the determinants of specificity for these 2 proteins by making a number of chimeric TFs in which we swapped different domains of Cbf1p and Tye7p and determined the effects on in vivo binding and cellular function. From these experiments, we learned that the Cbf1p dimer achieves its specificity by binding cooperatively with other Cbf1p dimers bound nearby. In contrast, we found that Tye7p achieves its specificity by binding cooperatively with 3 other DNA-binding proteins, Gcr1p, Gcr2p, and Rap1p. Remarkably, most promoters (63%) that are bound by Tye7p do not contain a consensus Tye7p binding site. Using this information, we were able to build simple models to accurately discriminate bound and unbound genomic loci for both Cbf1p and Tye7p. We then successfully reprogrammed the human bHLH NPAS2 to bind Cbf1p in vivo targets and a Tye7p target intergenic region to be bound by Cbf1p. These results demonstrate that the genome-wide binding targets of paralogous TFs can be discriminated using sequence information, and provide lessons about TF specificity that can be applied across the phylogenetic tree.
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