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Mi-Ichi F, Hamano S, Yoshida H. Links between cholesteryl sulfate-dependent and -independent processes in the morphological and physiological changes of Entamoeba encystation. Parasitol Int 2024; 99:102844. [PMID: 38103862 DOI: 10.1016/j.parint.2023.102844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/20/2023] [Accepted: 12/10/2023] [Indexed: 12/19/2023]
Abstract
The protozoan parasite Entamoeba histolytica causes amoebiasis, a global public health problem. Amoebiasis is solely transmitted by cysts that are produced from proliferative trophozoites by encystation in the large intestine of humans. During encystation, various metabolites, pathways, and cascades sequentially orchestrate the morphological and physiological changes required to produce cysts. Cholesteryl sulfate (CS) has recently been revealed to be among the key molecules that control the morphological and physiological changes of encystation by exerting pleiotropic effects. CS promotes the rounding of encysting Entamoeba cells and maintains this spherical morphology as encysting cells are surrounded by the cyst wall, a prerequisite for resistance against environmental stresses. CS is also involved in the development of membrane impermeability, another prerequisite for resistance. The initiation of cyst wall formation is, however, CS-independent. Here, we overview CS-dependent and -independent processes during encystation and discuss their functional linkage. We also discuss a potential transcriptional cascade that controls the processes necessary to produce dormant Entamoeba cysts.
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Affiliation(s)
- Fumika Mi-Ichi
- Central Laboratory, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan; Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan; The Joint Research Center on Tropical Diseases, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan.
| | - Shinjiro Hamano
- The Joint Research Center on Tropical Diseases, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nagasaki, Japan; Department of Parasitology, Institute of Tropical Medicine (NEKKEN), Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Hiroki Yoshida
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan
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2
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Gil Rosas M, Centola C, Torres M, Mouguelar VS, David AP, Piga EJ, Gomez D, Calcaterra NB, Armas P, Coux G. The transcription of the main gene associated with Treacher-Collins syndrome (TCOF1) is regulated by G-quadruplexes and cellular nucleic acid binding protein (CNBP). Sci Rep 2024; 14:7472. [PMID: 38553547 PMCID: PMC10980799 DOI: 10.1038/s41598-024-58255-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 03/27/2024] [Indexed: 04/02/2024] Open
Abstract
Treacle ribosome biogenesis factor 1 (TCOF1) is responsible for about 80% of mandibular dysostosis (MD) cases. We have formerly identified a correlation between TCOF1 and CNBP (CCHC-type zinc finger nucleic acid binding protein) expression in human mesenchymal cells. Given the established role of CNBP in gene regulation during rostral development, we explored the potential for CNBP to modulate TCOF1 transcription. Computational analysis for CNBP binding sites (CNBP-BSs) in the TCOF1 promoter revealed several putative binding sites, two of which (Hs791 and Hs2160) overlap with putative G-quadruplex (G4) sequences (PQSs). We validated the folding of these PQSs measuring circular dichroism and fluorescence of appropriate synthetic oligonucleotides. In vitro studies confirmed binding of purified CNBP to the target PQSs (both folded as G4 and unfolded) with Kd values in the nM range. ChIP assays conducted in HeLa cells chromatin detected the CNBP binding to TCOF1 promoter. Transient transfections of HEK293 cells revealed that Hs2160 cloned upstream SV40 promoter increased transcription of downstream firefly luciferase reporter gene. We also detected a CNBP-BS and PQS (Dr2393) in the zebrafish TCOF1 orthologue promoter (nolc1). Disrupting this G4 in zebrafish embryos by microinjecting DNA antisense oligonucleotides complementary to Dr2393 reduced the transcription of nolc1 and recapitulated the craniofacial anomalies characteristic of Treacher Collins Syndrome. Both cnbp overexpression and Morpholino-mediated knockdown in zebrafish induced nolc1 transcription. These results suggest that CNBP modulates the transcriptional expression of TCOF1 through a mechanism involving G-quadruplex folding/unfolding, and that this regulation is active in vertebrates as distantly related as bony fish and humans. These findings may have implications for understanding and treating MD.
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Affiliation(s)
- Mauco Gil Rosas
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda (S2000EZP), Rosario, Argentina
| | - Cielo Centola
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda (S2000EZP), Rosario, Argentina
| | - Mercedes Torres
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda (S2000EZP), Rosario, Argentina
| | - Valeria S Mouguelar
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda (S2000EZP), Rosario, Argentina
| | - Aldana P David
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda (S2000EZP), Rosario, Argentina
| | - Ernesto J Piga
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda (S2000EZP), Rosario, Argentina
| | - Dennis Gomez
- Institut de Pharmacologie et Biologie Structurale, UMR5089 CNRS-Universite de Toulouse, Equipe Labellisée Ligue Nationale contre le Cancer 2018, 31077, Toulouse, France
| | - Nora B Calcaterra
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda (S2000EZP), Rosario, Argentina
| | - Pablo Armas
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda (S2000EZP), Rosario, Argentina
| | - Gabriela Coux
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda (S2000EZP), Rosario, Argentina.
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3
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Lockman S, Genung M, Sheikholeslami K, Sher AA, Kroft D, Buist M, Olson CO, Toor B, Rastegar M. Transcriptional Inhibition of the Mecp2 Promoter by MeCP2E1 and MeCP2E2 Isoforms Suggests Negative Auto-Regulatory Feedback that can be Moderated by Metformin. J Mol Neurosci 2024; 74:14. [PMID: 38277073 DOI: 10.1007/s12031-023-02177-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Accepted: 12/29/2023] [Indexed: 01/27/2024]
Abstract
The epigenetic factor Methyl-CpG-Binding Protein 2 (MeCP2) is a nuclear protein that binds methylated DNA molecules (both 5-methylcytosine and 5-hydroxymethylcytosine) and controls gene transcription. MeCP2 is an important transcription factor that acts in a dose-dependent manner in the brain; thus, its optimal expression level in brain cells is important. As such, its deregulated expression, as well as gain- or loss-of-function mutation, lead to impaired neurodevelopment, and compromised structure and function of brain cells, particularly in neurons. Studies from others and us have characterized two well-recognized MeCP2 isoforms: MeCP2E1 and MeCP2E2. We have reported that in Daoy medulloblastoma brain cells, MeCP2E2 overexpression leads to MeCP2E1 protein degradation. Whether MeCP2 isoforms regulate the Mecp2 promoter regulatory elements remains unexplored. We previously showed that in Daoy cells, metformin (an anti-diabetic drug) induces MECP2E1 transcripts. However, possible impact of metformin on the Mecp2 promoter activity was not studied. Here, we generated stably transduced Daoy cell reporters to express EGFP driven by the Mecp2 promoter. Transduced cells were sorted into four EGFP-expressing groups (R4-to-R7) with different intensities of EGFP expression. Our results confirm that the Mecp2 promoter is active in Daoy cells, and that overexpression of either isoform inhibits the Mecp2 promoter activity, as detected by flow cytometry and luciferase reporter assays. Interestingly, metformin partially relieved the inhibitory effect of MeCP2E1 on the Mecp2 promoter, detected by flow cytometry. Taken together, our data provide important insight towards the regulation of MeCP2 isoforms at the promoter level, which might have biological relevance to the neurobiology of the brain.
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Affiliation(s)
- Sandhini Lockman
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Matthew Genung
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Kimia Sheikholeslami
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Annan Ali Sher
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Daniel Kroft
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Marjorie Buist
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Carl O Olson
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Brian Toor
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
| | - Mojgan Rastegar
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada.
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Ferrara S, Bertoni G. Genome-Scale Analysis of the Structure and Function of RNA Pathways and Networks in Pseudomonas aeruginosa. Methods Mol Biol 2024; 2721:183-195. [PMID: 37819523 DOI: 10.1007/978-1-0716-3473-8_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023]
Abstract
In recent years, several genome-wide approaches based on RNA sequencing (RNA-seq) have been developed. These methods allow a comprehensive and dynamic view of the structure and function of the multi-layered RNA pathways and networks. Many of these approaches, including the promising one of single-cell transcriptome analysis, have been successfully applied to Pseudomonas aeruginosa. However, we are only at the beginning because only a few surrounding conditions have been considered. Here, we aim to illustrate the different types of approaches based on RNA-seq that will lead us in the future to a better understanding of the dynamics of RNA biology in P. aeruginosa.
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Affiliation(s)
- Silvia Ferrara
- Department of Biosciences, Università degli Studi di Milano, Milan, Milano, Italy
| | - Giovanni Bertoni
- Department of Biosciences, Università degli Studi di Milano, Milan, Milano, Italy.
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Abstract
Wiring an animal brain is a complex process involving a staggering number of cell-types born at different times and locations in the developing brain. Incorporation of these cells into precise circuits with high fidelity is critical for animal survival and behavior. Assembly of neuronal circuits is heavily dependent upon proper timing of wiring programs, requiring neurons to express specific sets of genes (sometimes transiently) at the right time in development. While cell-type specificity of genetic programs regulating wiring has been studied in detail, mechanisms regulating proper timing and coordination of these programs across cell-types are only just beginning to emerge. In this review, we discuss some temporal regulators of wiring programs and how their activity is controlled over time and space. A common feature emerges from these temporal regulators - they are induced by cell-extrinsic cues and control transcription factors capable of regulating a highly cell-type specific set of target genes. Target specificity in these contexts comes from cell-type specific transcription factors. We propose that the spatiotemporal specificity of wiring programs is controlled by the combinatorial activity of temporal programs and cell-type specific transcription factors. Going forward, a better understanding of temporal regulators will be key to understanding the mechanisms underlying brain wiring, and will be critical for the development of in vitro models like brain organoids.
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Datsomor AK, Gillard G, Jin Y, Olsen RE, Sandve SR. Molecular Regulation of Biosynthesis of Long Chain Polyunsaturated Fatty Acids in Atlantic Salmon. Mar Biotechnol (NY) 2022; 24:661-670. [PMID: 35907166 PMCID: PMC9385821 DOI: 10.1007/s10126-022-10144-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
Salmon is a rich source of health-promoting omega-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA), such as eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3). The LC-PUFA biosynthetic pathway in Atlantic salmon is one of the most studied compared to other teleosts. This has largely been due to the massive replacement of LC-PUFA-rich ingredients in aquafeeds with terrestrial plant oils devoid of these essential fatty acids (EFA) which ultimately pushed dietary content towards the minimal requirement of EFA. The practice would also reduce tissue content of n-3 LC-PUFA compromising the nutritional value of salmon to the human consumer. These necessitated detailed studies of endogenous biosynthetic capability as a contributor to these EFA. This review seeks to provide a comprehensive and concise overview of the current knowledge about the molecular genetics of PUFA biosynthesis in Atlantic salmon, highlighting the enzymology and nutritional regulation as well as transcriptional control networks. Furthermore, we discuss the impact of genome duplication on the complexity of salmon LC-PUFA pathway and highlight probable implications on endogenous biosynthetic capabilities. Finally, we have also compiled and made available a large RNAseq dataset from 316 salmon liver samples together with an R-script visualization resource to aid in explorative and hypothesis-driven research into salmon lipid metabolism.
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Affiliation(s)
- Alex K. Datsomor
- Center for Integrative Genetics (CIGENE), Department of Animal and Aquacultural Sciences, Faculty of Biosciences, Norwegian University of Life Sciences, Ås, Norway
| | - Gareth Gillard
- Center for Integrative Genetics (CIGENE), Department of Animal and Aquacultural Sciences, Faculty of Biosciences, Norwegian University of Life Sciences, Ås, Norway
| | - Yang Jin
- Center for Integrative Genetics (CIGENE), Department of Animal and Aquacultural Sciences, Faculty of Biosciences, Norwegian University of Life Sciences, Ås, Norway
| | - Rolf E. Olsen
- Institute of Biology, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | - Simen R. Sandve
- Center for Integrative Genetics (CIGENE), Department of Animal and Aquacultural Sciences, Faculty of Biosciences, Norwegian University of Life Sciences, Ås, Norway
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Rodríguez-Campuzano AG, Hernández-Kelly LC, Ortega A. DNA Methylation-Dependent Gene Expression Regulation of Glutamate Transporters in Cultured Radial Glial Cells. Mol Neurobiol 2022; 59:1912-1924. [PMID: 35032319 DOI: 10.1007/s12035-022-02746-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 01/11/2022] [Indexed: 11/26/2022]
Abstract
Exposure to xenobiotics has a significant impact in brain physiology that could be liked to an excitotoxic process induced by a massive release of the main excitatory neurotransmitter, L-glutamate. Overstimulation of extra-synaptic glutamate receptors, mainly of the N-methyl-D-aspartate subtype leads to a disturbance of intracellular calcium homeostasis that is critically involved in neuronal death. Hence, glutamate extracellular levels are tightly regulated through its uptake by glial glutamate transporters. It has been observed that glutamate regulates its own removal, both in the short-time frame via a transporter-mediated decrease in the uptake, and in the long-term through the transcriptional control of its gene expression, a process mediated by glutamate receptors that involves the Ca2+/diacylglycerol-dependent protein kinase and the transcription factor Ying Yang 1. Taking into consideration that this transcription factor is a member of the Polycomb complex and thus, part of repressive and activating chromatin remodeling factors, it might direct the interaction of DNA methyltransferases or dioxygenases of methylated cytosines to their target sequences. Here we explored the role of dynamic DNA methylation in the expression and function of glial glutamate transporters. To this end, we used the well-characterized models of primary cultures of chick cerebellar Bergmann glia cells and a human retina-derived Müller glia cell line. A time and dose-dependent increase in global DNA methylation was evident upon glutamate exposure. Under hypomethylation conditions, the glial glutamate transporter protein levels and uptake activity were increased. These results favor the notion that a dynamic DNA methylation program triggered by glutamate in glial cells modulates one of its major functions: glutamate removal.
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Affiliation(s)
- Ada G Rodríguez-Campuzano
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. IPN 2508, Zacatenco Ciudad de México, 07360, México
| | - Luisa C Hernández-Kelly
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. IPN 2508, Zacatenco Ciudad de México, 07360, México
| | - Arturo Ortega
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Av. IPN 2508, Zacatenco Ciudad de México, 07360, México.
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Abstract
Endogenous gene activation by programmable transcription factors offers gene-dose-dependent phenotyping of target cells embedded in their in vivo natural tissue environment. Modified CRISPR/Cas9 systems were developed to be used as guide (g) RNA programmable transcriptional activation platforms (CRISPRa) in vitro and in vivo allowing targeted or multiplexed gene activation studies. We specifically developed these tools to be applied in cardiomyocytes providing dCas9VPR expressing mice under the control of the Myosin heavy chain 6 (Myh6) promoter. Here, we describe a protocol for the efficient design and validation of newly identified gRNA for enhancing transcriptional activity of a selected gene of interest. Additionally, we are providing insights into a downstream application in a dCas9VPR expressing mouse model specifically for cardiomyocyte biology.
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Affiliation(s)
- Eric Schoger
- Institute of Pharmacology & Toxicology, University Medical Center Göttingen, Georg-August-University Göttingen, Göttingen, Germany
- German Center for Cardiovascular Research (DZHK e.V.), Göttingen, Germany
- Georg-August-University Göttingen, Göttingen, Germany
| | - Laura C Zelarayán
- Institute of Pharmacology & Toxicology, University Medical Center Göttingen, Georg-August-University Göttingen, Göttingen, Germany.
- German Center for Cardiovascular Research (DZHK e.V.), Göttingen, Germany.
- Georg-August-University Göttingen, Göttingen, Germany.
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9
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Amaro IA, Ahmed-Braimah YH, League GP, Pitcher SA, Avila FW, Cruz PC, Harrington LC, Wolfner MF. Seminal fluid proteins induce transcriptome changes in the Aedes aegypti female lower reproductive tract. BMC Genomics 2021; 22:896. [PMID: 34906087 PMCID: PMC8672594 DOI: 10.1186/s12864-021-08201-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 11/23/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Mating induces behavioral and physiological changes in the arbovirus vector Aedes aegypti, including stimulation of egg development and oviposition, increased survival, and reluctance to re-mate with subsequent males. Transferred seminal fluid proteins and peptides derived from the male accessory glands induce these changes, though the mechanism by which they do this is not known. RESULTS To determine transcriptome changes induced by seminal proteins, we injected extract from male accessory glands and seminal vesicles (MAG extract) into females and examined female lower reproductive tract (LRT) transcriptomes 24 h later, relative to non-injected controls. MAG extract induced 87 transcript-level changes, 31 of which were also seen in a previous study of the LRT 24 h after a natural mating, including 15 genes with transcript-level changes similarly observed in the spermathecae of mated females. The differentially-regulated genes are involved in diverse molecular processes, including immunity, proteolysis, neuronal function, transcription control, or contain predicted small-molecule binding and transport domains. CONCLUSIONS Our results reveal that seminal fluid proteins, specifically, can induce gene expression responses after mating and identify gene targets to further investigate for roles in post-mating responses and potential use in vector control.
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Affiliation(s)
- I Alexandra Amaro
- Department of Entomology, Cornell University, Ithaca, NY, 14853, USA
| | | | - Garrett P League
- Department of Entomology, Cornell University, Ithaca, NY, 14853, USA
| | - Sylvie A Pitcher
- Department of Entomology, Cornell University, Ithaca, NY, 14853, USA
| | - Frank W Avila
- Max Planck Tandem Group in Mosquito Reproductive Biology, Universidad de Antioquia, Medellín, 050010, Colombia
| | - Priscilla C Cruz
- Department of Entomology, Cornell University, Ithaca, NY, 14853, USA
| | | | - Mariana F Wolfner
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14853, USA.
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Bai Y, Caussinus E, Leo S, Bosshardt F, Myachina F, Rot G, Robinson MD, Lehner CF. A cis-regulatory element promoting increased transcription at low temperature in cultured ectothermic Drosophila cells. BMC Genomics 2021; 22:771. [PMID: 34711176 PMCID: PMC8555087 DOI: 10.1186/s12864-021-08057-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 10/06/2021] [Indexed: 02/06/2023] Open
Abstract
Background Temperature change affects the myriad of concurrent cellular processes in a non-uniform, disruptive manner. While endothermic organisms minimize the challenge of ambient temperature variation by keeping the core body temperature constant, cells of many ectothermic species maintain homeostatic function within a considerable temperature range. The cellular mechanisms enabling temperature acclimation in ectotherms are still poorly understood. At the transcriptional level, the heat shock response has been analyzed extensively. The opposite, the response to sub-optimal temperature, has received lesser attention in particular in animal species. The tissue specificity of transcriptional responses to cool temperature has not been addressed and it is not clear whether a prominent general response occurs. Cis-regulatory elements (CREs), which mediate increased transcription at cool temperature, and responsible transcription factors are largely unknown. Results The ectotherm Drosophila melanogaster with a presumed temperature optimum around 25 °C was used for transcriptomic analyses of effects of temperatures at the lower end of the readily tolerated range (14–29 °C). Comparative analyses with adult flies and cell culture lines indicated a striking degree of cell-type specificity in the transcriptional response to cool. To identify potential cis-regulatory elements (CREs) for transcriptional upregulation at cool temperature, we analyzed temperature effects on DNA accessibility in chromatin of S2R+ cells. Candidate cis-regulatory elements (CREs) were evaluated with a novel reporter assay for accurate assessment of their temperature-dependency. Robust transcriptional upregulation at low temperature could be demonstrated for a fragment from the pastrel gene, which expresses more transcript and protein at reduced temperatures. This CRE is controlled by the JAK/STAT signaling pathway and antagonizing activities of the transcription factors Pointed and Ets97D. Conclusion Beyond a rich data resource for future analyses of transcriptional control within the readily tolerated range of an ectothermic animal, a novel reporter assay permitting quantitative characterization of CRE temperature dependence was developed. Our identification and functional dissection of the pst_E1 enhancer demonstrate the utility of resources and assay. The functional characterization of this CoolUp enhancer provides initial mechanistic insights into transcriptional upregulation induced by a shift to temperatures at the lower end of the readily tolerated range. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-08057-4.
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Affiliation(s)
- Yu Bai
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Emmanuel Caussinus
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Stefano Leo
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Fritz Bosshardt
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Faina Myachina
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Gregor Rot
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.,SIB Swiss Institute of Bioinformatics, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Mark D Robinson
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.,SIB Swiss Institute of Bioinformatics, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Christian F Lehner
- Department of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.
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11
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Poturnajova M, Kozovska Z, Matuskova M. Aldehyde dehydrogenase 1A1 and 1A3 isoforms - mechanism of activation and regulation in cancer. Cell Signal 2021; 87:110120. [PMID: 34428540 PMCID: PMC8505796 DOI: 10.1016/j.cellsig.2021.110120] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 12/15/2022]
Abstract
In some types of human cancer, aldehyde dehydrogenases represent stemness markers and their expression is associated with advanced disease stages and poor prognosis. Although several biological functions are mediated by their product Retinoid acid, the molecular mechanism is tissue-dependent and only partially understood. In this review, we summarize the current knowledge about the role of ALDH in solid tumours, especially ALDH1A1 and ALDH1A3 isoforms, regarding the molecular mechanism of their transcription and regulation, and their crosstalk with main molecular pathways resulting in the excessive proliferation, chemoresistance, stem cells properties and invasiveness. The recent knowledge of the regulatory effect of lnRNA on ALDH1A1 and ALDH1A3 is discussed too. Aldehyde dehydrogenases are important stem cell markers in many human cancer types. ALDH1A1 or ALDH1A3 activation participates in tumour progression, chemoresistance, stem-cell properties and invasiveness. ALDH1A1 interacts with oncogenic pathways Notch, NRF, CXCR4, Polycomb, MDR, and HOX.
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Affiliation(s)
- M Poturnajova
- Department of Molecular Oncology, Cancer Research Institute, Biomedical Research Center of Slovak Academy of Sciences, Dubravska cesta 9, 84505 Bratislava, Slovakia.
| | - Z Kozovska
- Department of Molecular Oncology, Cancer Research Institute, Biomedical Research Center of Slovak Academy of Sciences, Dubravska cesta 9, 84505 Bratislava, Slovakia
| | - M Matuskova
- Department of Molecular Oncology, Cancer Research Institute, Biomedical Research Center of Slovak Academy of Sciences, Dubravska cesta 9, 84505 Bratislava, Slovakia
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12
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Juban G. Transcriptional control of macrophage inflammatory shift during skeletal muscle regeneration. Semin Cell Dev Biol 2021; 119:82-88. [PMID: 34183241 DOI: 10.1016/j.semcdb.2021.06.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 06/13/2021] [Accepted: 06/18/2021] [Indexed: 01/05/2023]
Abstract
Skeletal muscle is a tissue able to fully regenerate after an acute injury. Macrophages play an essential role during skeletal muscle regeneration. Resolution of inflammation is a crucial step during the regeneration process, allowing to contain the inflammatory response to avoid damage of the healthy surrounding muscle and triggers the recovery phase during which the muscle regenerates. Resolution of inflammation is mainly mediated by macrophage phenotypic shift that is the transition from a pro-inflammatory damage associated profile towards an anti-inflammatory restorative phenotype, which is characterized by a major transcriptional rewiring. Failure of the resolution of inflammation is observed in chronic diseases such as degenerative myopathies where permanent asynchronous muscle injuries trigger contradictory inflammatory cues, leading to fibrosis and alteration of muscle function. This review will focus on the described molecular pathways that control macrophage inflammatory shift during skeletal muscle regeneration. First, we will highlight the transcriptional changes that characterize macrophage inflammatory shift during skeletal muscle regeneration. Then, we will describe how the signaling pathways and the metabolic changes associated with this shift are controlled. Finally, we will emphasize the transcription factors involved.
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Affiliation(s)
- Gaëtan Juban
- Institut NeuroMyoGène, Université Claude Bernard Lyon 1, CNRS UMR 5310, INSERM U1217, Université de Lyon, Lyon, France.
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13
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Masoudi N, Yemini E, Schnabel R, Hobert O. Piecemeal regulation of convergent neuronal lineages by bHLH transcription factors in Caenorhabditis elegans. Development 2021; 148:dev199224. [PMID: 34100067 PMCID: PMC8217713 DOI: 10.1242/dev.199224] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 04/29/2021] [Indexed: 11/20/2022]
Abstract
Cells of the same type can be generated by distinct cellular lineages that originate in different parts of the developing embryo ('lineage convergence'). Several Caenorhabditis elegans neuron classes composed of left/right or radially symmetric class members display such lineage convergence. We show here that the C. elegans Atonal homolog lin-32 is differentially expressed in neuronal lineages that give rise to left/right or radially symmetric class members. Loss of lin-32 results in the selective loss of the expression of pan-neuronal markers and terminal selector-type transcription factors that confer neuron class-specific features. Another basic helix-loop-helix (bHLH) gene, the Achaete-Scute homolog hlh-14, is expressed in a mirror image pattern relative to lin-32 and is required to induce neuronal identity and terminal selector expression on the contralateral side of the animal. These findings demonstrate that distinct lineage histories converge via different bHLH factors at the level of induction of terminal selector identity determinants, which thus serve as integrators of distinct lineage histories. We also describe neuron-to-neuron identity transformations in lin-32 mutants, which we propose to also be the result of misregulation of terminal selector gene expression.
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Affiliation(s)
- Neda Masoudi
- Department of Biological Sciences, Columbia University, Howard Hughes Medical Institute, New York, NY 10027, USA
| | - Eviatar Yemini
- Department of Biological Sciences, Columbia University, Howard Hughes Medical Institute, New York, NY 10027, USA
| | - Ralf Schnabel
- Institute of Genetics, Technische Universität Braunschweig, 38106 Braunschweig, Germany
| | - Oliver Hobert
- Department of Biological Sciences, Columbia University, Howard Hughes Medical Institute, New York, NY 10027, USA
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14
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Abstract
GFI1 and GFI1B are small nuclear proteins of 45 and 37kDa, respectively, that have a simple two-domain structure: The first consists of a group of six c-terminal C2H2 zinc finger motifs that are almost identical in sequence and bind to very similar, specific DNA sites. The second is an N-terminal 20 amino acid SNAG domain that can bind to the pocket of the histone demethylase KDM1A (LSD1) near its active site. When bound to DNA, both proteins act as bridging factors that bring LSD1 and associated proteins into the vicinity of methylated substrates, in particular histone H3 or TP53. GFI1 can also bring methyl transferases such as PRMT1 together with its substrates that include the DNA repair proteins MRE11 and 53BP1, thereby enabling their methylation and activation. While GFI1B is expressed almost exclusively in the erythroid and megakaryocytic lineage, GFI1 has clear biological roles in the development and differentiation of lymphoid and myeloid immune cells. GFI1 is required for lymphoid/myeloid and monocyte/granulocyte lineage decision as well as the correct nuclear interpretation of a number of important immune-signaling pathways that are initiated by NOTCH1, interleukins such as IL2, IL4, IL5 or IL7, by the pre TCR or -BCR receptors during early lymphoid differentiation or by T and B cell receptors during activation of lymphoid cells. Myeloid cells also depend on GFI1 at both stages of early differentiation as well as later stages in the process of activation of macrophages through Toll-like receptors in response to pathogen-associated molecular patterns. The knowledge gathered on these factors over the last decades puts GFI1 and GFI1B at the center of many biological processes that are critical for both the innate and acquired immune system.
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15
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Abstract
Transcriptional coactivator with PDZ-binding motif (TAZ) has been extensively characterized in organ development, tissue regeneration, and tumor progression. In particular, TAZ functions as a Hippo mediator that regulates organ size, tumor growth and migration. It is highly expressed in various types of human cancer, and has been reported to be associated with tumor metastasis and poor outcomes in cancer patients, suggesting that TAZ is an oncogenic regulator. Yes-associated protein (YAP) has 60% similarity in amino acid sequence to TAZ and plays redundant roles with TAZ in the regulation of cell proliferation and migration of cancer cells. Therefore, TAZ and YAP, which are encoded by paralogous genes, are referred to as TAZ/YAP and are suggested to be functionally equivalent. Despite its similarity to YAP, TAZ can be clearly distinguished from YAP based on its genetic, structural, and functional aspects. In addition, targeting superabundant TAZ can be a promising therapeutic strategy for cancer treatment; however, persistent TAZ inactivation may cause failure of tissue homeostatic control. This review focuses primarily on TAZ, not YAP, discusses its structural features and physiological functions in the regulation of tissue homeostasis, and provides new insights into the drug development targeting TAZ to control reproductive and musculoskeletal disorders.
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Affiliation(s)
- Mi Gyeong Jeong
- College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, C206 Science building, 52 Ewhayeodae-Gil, Seodaemun-Gu, Seoul, 03760, Korea
| | - Hyo Kyeong Kim
- College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, C206 Science building, 52 Ewhayeodae-Gil, Seodaemun-Gu, Seoul, 03760, Korea
| | - Eun Sook Hwang
- College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, C206 Science building, 52 Ewhayeodae-Gil, Seodaemun-Gu, Seoul, 03760, Korea.
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Ji H, Liu D, Yang Z. High oil accumulation in tuber of yellow nutsedge compared to purple nutsedge is associated with more abundant expression of genes involved in fatty acid synthesis and triacylglycerol storage. Biotechnol Biofuels 2021; 14:54. [PMID: 33653389 PMCID: PMC7923336 DOI: 10.1186/s13068-021-01909-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 02/18/2021] [Indexed: 05/10/2023]
Abstract
BACKGROUND Yellow nutsedge is a unique plant species that can accumulate up to 35% oil of tuber dry weight, perhaps the highest level observed in the tuber tissues of plant kingdom. To gain insight into the molecular mechanism that leads to high oil accumulation in yellow nutsedge, gene expression profiles of oil production pathways involved carbon metabolism, fatty acid synthesis, triacylglycerol synthesis, and triacylglycerol storage during tuber development were compared with purple nutsedge, the closest relative of yellow nutsedge that is poor in oil accumulation. RESULTS Compared with purple nutsedge, high oil accumulation in yellow nutsedge was associated with significant up-regulation of specific key enzymes of plastidial RubisCO bypass as well as malate and pyruvate metabolism, almost all fatty acid synthesis enzymes, and seed-like oil-body proteins. However, overall transcripts for carbon metabolism toward carbon precursor for fatty acid synthesis were comparable and for triacylglycerol synthesis were similar in both species. Two seed-like master transcription factors ABI3 and WRI1 were found to display similar transcript patterns but were expressed at 6.5- and 14.3-fold higher levels in yellow nutsedge than in purple nutsedge, respectively. A weighted gene co-expression network analysis revealed that ABI3 was in strong transcriptional coordination with WRI1 and other key oil-related genes. CONCLUSIONS These results implied that pyruvate availability and fatty acid synthesis in plastid, along with triacylglycerol storage in oil bodies, rather than triacylglycerol synthesis in endoplasmic reticulum, are the major factors responsible for high oil production in tuber of yellow nutsedge, and ABI3 most likely plays a critical role in regulating oil accumulation. This study is of significance with regard to understanding the molecular mechanism controlling carbon partitioning toward oil production in oil-rich tuber and provides a valuable reference for enhancing oil accumulation in non-seed tissues of crops through genetic breeding or metabolic engineering.
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Affiliation(s)
- Hongying Ji
- Key Lab of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Dantong Liu
- Key Lab of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093 China
- University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Zhenle Yang
- Key Lab of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093 China
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Franzellitti S, Prada F, Viarengo A, Fabbri E. Evaluating bivalve cytoprotective responses and their regulatory pathways in a climate change scenario. Sci Total Environ 2020; 720:137733. [PMID: 32325610 DOI: 10.1016/j.scitotenv.2020.137733] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/28/2020] [Accepted: 03/02/2020] [Indexed: 06/11/2023]
Abstract
Temperature is a relevant abiotic factor affecting physiological performance and distribution of marine animals in natural environments. The changes in global seawater temperatures make it necessary to understand how molecular mechanisms operate under the cumulative effects of global climate change and chemical pollution to promote/hamper environmental acclimatization. Marine mussels are excellent model organisms to infer the impacts of those anthropogenic threats on coastal ecosystems. In this study, Mediterranean mussels (Mytilus galloprovincialis) were exposed to different concentrations of the metal copper (Cu as CuCl2: 2.5, 5, 10, 20, 40 μg/L) or the antibiotic oxytetracycline (OTC: 0.1, 1, 10, 100, 1000 μg/L) at increasing seawater temperatures (16 °C, 20 °C, 24 °C). Transcriptional modulation of a 70-kDa heat shock protein (HSP70) and of the ABC transporter P-glycoprotein (P-gp, encoded by the ABCB gene) was assessed along with the cAMP/PKA signaling pathway regulating both gene expressions. At the physiological temperature of mussels (16 °C), Cu and OTC induced bimodal changes of cAMP levels and PKA activities in gills of exposed animals. A correlation between OTC- or Cu- induced changes of PKA activity and expression of hsp70 and ABCB was observed. Temperature increases (up to 24 °C) altered ABCB and hsp70 responses to the pollutants and disrupted their relationship with cAMP/PKA modulation, leading to loss of correlation between the biological endpoints. On the whole, the results indicate that temperature may impair the effects of inorganic and organic chemicals on the cAMP/PKA signaling pathway of mussels, in turn altering key molecular mediators of physiological plasticity and cytoprotection.
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Affiliation(s)
- Silvia Franzellitti
- Animal and Environmental Physiology Laboratory, Department of Biological, Geological and Environmental Sciences (BiGeA), University of Bologna, Ravenna, Italy; Fano Marine Center, Department of Biological, Geological, and Environmental Sciences (BiGeA), University of Bologna, Fano, Italy.
| | - Fiorella Prada
- Fano Marine Center, Department of Biological, Geological, and Environmental Sciences (BiGeA), University of Bologna, Fano, Italy; Marine Science Group, Department of Biological, Geological, and Environmental Sciences (BiGeA), University of Bologna, Bologna, Italy
| | - Aldo Viarengo
- Ecotoxicology and Environmental Safety Unit, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy
| | - Elena Fabbri
- Animal and Environmental Physiology Laboratory, Department of Biological, Geological and Environmental Sciences (BiGeA), University of Bologna, Ravenna, Italy
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18
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Blankvoort S, Descamps LAL, Kentros C. Enhancer-Driven Gene Expression (EDGE) enables the generation of cell type specific tools for the analysis of neural circuits. Neurosci Res 2020; 152:78-86. [PMID: 31958494 DOI: 10.1016/j.neures.2020.01.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 01/10/2020] [Accepted: 01/10/2020] [Indexed: 12/20/2022]
Abstract
As in all circuits, fully understanding how neural circuits operate requires the ability to specifically manipulate individual circuit elements, i.e. particular neuronal cell types. While recent years saw the development of molecular genetic tools allowing one to control and monitor neuronal activity, progress is limited by the ability to express such transgenes specifically enough. This goal is complicated by the fact that we are only beginning to understand how many cell types exist in the mammalian brain. Obtaining neuronal cell type-specific expression requires co-opting the genetic machinery which specifies their striking diversity, typically done by making transgenic animals using promoters expressing in neurons. However, while the vast majority of genes express in the brain, they almost always express in multiple cell types, meaning native promoters are not specific enough. We have recently taken a new approach to increase the specificity of transgene expression based upon identifying the distal cis-regulatory genomic elements (i.e. enhancers) uniquely active in a brain region and combining them with a heterologous minimal promoter. Termed Enhancer-Driven Gene Expression (EDGE), it allows for the generation of transgenic animals targeting the cell types of any brain region with far greater specificity than can be obtained with native promoters. Moreover, their small size allows for the generation of cell-specific viral vectors, conceivably enabling circuit-specific manipulations to any species.
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Affiliation(s)
- Stefan Blankvoort
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway.
| | - Lucie A L Descamps
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway
| | - Cliff Kentros
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, NTNU, Trondheim, Norway.
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Leyva-Díaz E, Hobert O. Transcription factor autoregulation is required for acquisition and maintenance of neuronal identity. Development 2019; 146:146/13/dev177378. [PMID: 31227642 DOI: 10.1242/dev.177378] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/13/2019] [Indexed: 01/02/2023]
Abstract
The expression of transcription factors that initiate the specification of a unique cellular identity in multicellular organisms is often maintained throughout the life of the respective cell type via an autoregulatory mechanism. It is generally assumed that such autoregulation serves to maintain the differentiated state of a cell. To experimentally test this assumption, we used CRISPR/Cas9-mediated genome engineering to delete a transcriptional autoregulatory, cis-acting motif in the che-1 zinc-finger transcription factor locus, a terminal selector required to specify the identity of the ASE neuron pair during embryonic development of the nematode Caenorhabditis elegans. We show that che-1 autoregulation is indeed required to maintain the differentiated state of the ASE neurons but that it is also required to amplify che-1 expression during embryonic development to reach an apparent minimal threshold to initiate the ASE differentiation program. We conclude that transcriptional autoregulation fulfills two intrinsically linked purposes: one in proper initiation, the other in proper maintenance of terminal differentiation programs.This article has an associated 'The people behind the papers' interview.
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Affiliation(s)
- Eduardo Leyva-Díaz
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, NY 10027, USA
| | - Oliver Hobert
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, NY 10027, USA
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20
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Pierrat MJ, Marsaud V, Mauviel A, Javelaud D. Transcriptional repression of the tyrosinase-related protein 2 gene by transforming growth factor-β and the Kruppel-like transcription factor GLI2. J Dermatol Sci 2019; 94:321-329. [PMID: 31208857 DOI: 10.1016/j.jdermsci.2019.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 02/21/2019] [Accepted: 04/01/2019] [Indexed: 01/09/2023]
Abstract
BACKGROUND Tyrosinase-Related Protein 2 (TRP2) is an enzyme involved in melanogenesis, that also exerts proliferative, anti-apoptotic and immunogenic functions in melanoma cells. TRP2 transcription is regulated by the melanocytic master transcription factor MITF. GLI2, a transcription factor that acts downstream of Hedgehog signaling, is also a direct transcriptional target of the TGF-β/SMAD pathway that contributes to melanoma progression and exerts transcriptional antagonistic activities against MITF. OBJECTIVES To characterize the molecular events responsible for TGF-β and GLI2 repression of TRP2 expression. METHODS In silico promoter analysis, transient cell transfection experiments with 5'-end TRP2 promoter deletion constructs, chromatin immuno-precipitation, and site-directed promoter mutagenesis were used to dissect the molecular mechanisms of TRP2 gene regulation by TGF-β and GLI2. RESULTS We demonstrate that TGF-β and GLI2-specific TRP2 repression involves direct mechanisms that occur in addition to MITF downregulation by TGF-β and GLI2. We identify two functional GLI2 binding sites within the TRP2 promoter that are critical for TGF-β and GLI2 responsiveness, one of them overlapping a CREB binding site. GLI2 and CREB competing for the same cis-element is associated with opposite transcriptional outcome. CONCLUSION Our results further refine the understanding of how TGF-β and GLI2 control the phenotypic plasticity of melanoma cells. In particular, we identify critical GLI2-binding cis-elements within the TRP2 promoter region that allow for its transcriptional repression independently from MITF concomitant downregulation.
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Affiliation(s)
- Marie-Jeanne Pierrat
- Institut Curie, PSL Research University, INSERM U1021, CNRS UMR3347, Team "TGF-ß and Oncogenesis", Equipe Labellisée LIGUE 2016, F-91400, Orsay, France; Université Paris-Sud, F-91400, Orsay, France
| | - Véronique Marsaud
- Institut Curie, PSL Research University, INSERM U1021, CNRS UMR3347, Team "TGF-ß and Oncogenesis", Equipe Labellisée LIGUE 2016, F-91400, Orsay, France; Université Paris-Sud, F-91400, Orsay, France
| | - Alain Mauviel
- Institut Curie, PSL Research University, INSERM U1021, CNRS UMR3347, Team "TGF-ß and Oncogenesis", Equipe Labellisée LIGUE 2016, F-91400, Orsay, France; Université Paris-Sud, F-91400, Orsay, France.
| | - Delphine Javelaud
- Institut Curie, PSL Research University, INSERM U1021, CNRS UMR3347, Team "TGF-ß and Oncogenesis", Equipe Labellisée LIGUE 2016, F-91400, Orsay, France; Université Paris-Sud, F-91400, Orsay, France.
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21
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Pyfrom SC, Luo H, Payton JE. PLAIDOH: a novel method for functional prediction of long non-coding RNAs identifies cancer-specific LncRNA activities. BMC Genomics 2019; 20:137. [PMID: 30767760 PMCID: PMC6377765 DOI: 10.1186/s12864-019-5497-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 01/29/2019] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Long non-coding RNAs (lncRNAs) exhibit remarkable cell-type specificity and disease association. LncRNA's functional versatility includes epigenetic modification, nuclear domain organization, transcriptional control, regulation of RNA splicing and translation, and modulation of protein activity. However, most lncRNAs remain uncharacterized due to a shortage of predictive tools available to guide functional experiments. RESULTS To address this gap for lymphoma-associated lncRNAs identified in our studies, we developed a new computational method, Predicting LncRNA Activity through Integrative Data-driven 'Omics and Heuristics (PLAIDOH), which has several unique features not found in other methods. PLAIDOH integrates transcriptome, subcellular localization, enhancer landscape, genome architecture, chromatin interaction, and RNA-binding (eCLIP) data and generates statistically defined output scores. PLAIDOH's approach identifies and ranks functional connections between individual lncRNA, coding gene, and protein pairs using enhancer, transcript cis-regulatory, and RNA-binding protein interactome scores that predict the relative likelihood of these different lncRNA functions. When applied to 'omics datasets that we collected from lymphoma patients, or to publicly available cancer (TCGA) or ENCODE datasets, PLAIDOH identified and prioritized well-known lncRNA-target gene regulatory pairs (e.g., HOTAIR and HOX genes, PVT1 and MYC), validated hits in multiple lncRNA-targeted CRISPR screens, and lncRNA-protein binding partners (e.g., NEAT1 and NONO). Importantly, PLAIDOH also identified novel putative functional interactions, including one lymphoma-associated lncRNA based on analysis of data from our human lymphoma study. We validated PLAIDOH's predictions for this lncRNA using knock-down and knock-out experiments in lymphoma cell models. CONCLUSIONS Our study demonstrates that we have developed a new method for the prediction and ranking of functional connections between individual lncRNA, coding gene, and protein pairs, which were validated by genetic experiments and comparison to published CRISPR screens. PLAIDOH expedites validation and follow-on mechanistic studies of lncRNAs in any biological system. It is available at https://github.com/sarahpyfrom/PLAIDOH .
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Affiliation(s)
- Sarah C. Pyfrom
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110 USA
| | - Hong Luo
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110 USA
| | - Jacqueline E. Payton
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110 USA
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Abstract
The primary female sex hormones, estrogens, are responsible for the control of functions of the female reproductive system, as well as the development of secondary sexual characteristics that appear during puberty and sexual maturity. Estrogens exert their actions by binding to specific receptors, the estrogen receptors (ERs), which in turn activate transcriptional processes and/or signaling events that result in the control of gene expression. These actions can be mediated by direct binding of estrogen receptor complexes to specific sequences in gene promoters (genomic effects), or by mechanisms that do not involve direct binding to DNA (non-genomic effects). Whether acting via direct nuclear effects, indirect non-nuclear actions, or a combination of both, the effects of estrogens on gene expression are controlled by highly regulated complex mechanisms. In this chapter, we summarize the knowledge gained in the past 60years since the discovery of the estrogen receptors on the mechanisms governing estrogen-mediated gene expression. We provide an overview of estrogen biosynthesis, and we describe the main mechanisms by which the female sex hormone controls gene transcription in different tissues and cell types. Specifically, we address the molecular events governing regulation of gene expression via the nuclear estrogen receptors (ERα, and ERβ) and the membrane estrogen receptor (GPER1). We also describe mechanisms of cross-talk between signaling cascades activated by both nuclear and membrane estrogen receptors. Finally, we discuss natural compounds that are able to target specific estrogen receptors and their implications for human health and medical therapeutics.
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Affiliation(s)
- Nathalie Fuentes
- Department of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Patricia Silveyra
- Department of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA, United States; The University of North Carolina at Chapel Hill, School of Nursing, Chapel Hill, NC, United States.
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Abstract
Interferon gamma, referred to here as IFN-γ, is a major component in immunological cell signaling and is a critical regulatory protein for overall immune system function. First discovered in 1965 (Wheelock Science 149: (3681)310-311, 1965), IFN-γ is the only Type II interferon identified. Its expression is both positively and negatively controlled by different factors. In this chapter, we will review the transcriptional and post-transcriptional control of IFN-γ expression. In the transcriptional control part, the regular activators and suppressors are summarized, we will also focus on the epigenetic control, such as chromosome access, DNA methylation, and histone acetylation. The more we learn about the control of this regulatory protein will allow us to apply this knowledge in the future to effectively manipulate IFN-γ expression for the treatment of infections, cancer, inflammation, and autoimmune diseases.
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Ramsey J, Martin EC, Purcell OM, Lee KM, MacLean AG. Self-injurious behaviours in rhesus macaques: Potential glial mechanisms. J Intellect Disabil Res 2018; 62:1008-1017. [PMID: 30450801 PMCID: PMC6385863 DOI: 10.1111/jir.12558] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 06/20/2018] [Accepted: 09/28/2018] [Indexed: 06/09/2023]
Abstract
BACKGROUND Self-injurious behaviour (SIB) can be classified as intentional, direct injuring of body tissue usually without suicidal intent. In its non-suicidal form it is commonly seen as a clinical sign of borderline personality disorder, autism, PTSD, depression, and anxiety affecting a wide range of ages and conditions. In rhesus macaques SIB is most commonly manifested through hair plucking, self-biting, self-hitting, and head banging. SIB in the form of self-biting is observed in approximately 5-15% of individually housed monkeys. Recently, glial cells are becoming recognised as key players in regulating behaviours. METHOD The goal of this study was to determine the role of glial activation, including astrocytes, in macaques that had displayed SIB. To this end, we performed immunohistochemistry and next generation sequence of brain tissues from rhesus macaques with SIB. RESULTS Our studies showed increased vimentin, but not nestin, expression on astrocytes of macaques displaying SIB. Initial RNA Seq analyses indicate activation of pathways involved in tissue remodelling, neuroinflammation and cAMP signalling. CONCLUSIONS Glia are most probably activated in primates with self-injury, and are therefore potential novel targets for therapeutics.
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Affiliation(s)
- Joseph Ramsey
- Tulane Program in Neuroscience, Tulane University, New Orleans, LA 70112
| | - Elizabeth C. Martin
- Center for Stem Cell Research and Regenerative Medicine, School of Medicine, Tulane University, New Orleans, LA 70112
| | - Olivia M. Purcell
- Tulane Program in Neuroscience, Tulane University, New Orleans, LA 70112
| | - Kim M. Lee
- Tulane National Primate Research Center, Covington, LA 70433
- Tulane Program in Biomedical Science, Tulane Medical School, New Orleans, LA 70112
| | - Andrew G. MacLean
- Tulane Program in Neuroscience, Tulane University, New Orleans, LA 70112
- Tulane National Primate Research Center, Covington, LA 70433
- Tulane Program in Biomedical Science, Tulane Medical School, New Orleans, LA 70112
- Department of Microbiology & Immunology, Tulane Medical School, New Orleans, LA 70112
- Tulane Center for Aging, Tulane University New Orleans, LA 70112
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25
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Nakashima K, Tsuchiya M, Fukushima S, Abe J, Kanazawa A. Transcription of soybean retrotransposon SORE-1 is temporally upregulated in developing ovules. Planta 2018; 248:1331-1337. [PMID: 30209619 DOI: 10.1007/s00425-018-3005-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 08/27/2018] [Indexed: 06/08/2023]
Abstract
MAIN CONCLUSION Transcription of soybean retrotransposon SORE-1 was temporally upregulated during ovule development. This transcriptional pattern was under intrinsic control conferred by the long terminal repeat of SORE-1. Transcriptionally active retrotransposons are capable of inducing random disruption of genes, providing a powerful tool for mutagenesis. Activation of retrotransposons in reproductive cells, in particular, can lead to heritable changes. Here, we examined developmental control of transcription of soybean retrotransposon SORE-1. Transgenic Arabidopsis plants that contain β-glucuronidase (GUS) reporter gene fused with the SORE-1 long terminal repeat (LTR) had GUS staining in the ovule. Quantitative analysis of transcripts in plants with this DNA construct and those with the full-length SORE-1 element indicated a temporal upregulation of SORE-1 transcription during ovule development. A comparable phenomenon was also observed in soybean plants that had a recent insertion of this element in the GmphyA2 gene. These results provide evidence that the temporal upregulation of SORE-1 in the reproductive organ is sufficiently controlled by its LTR and indicate that the intrinsic expression pattern of SORE-1 is consistent with its mutagenic property.
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Affiliation(s)
- Kenta Nakashima
- Research Faculty of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo, 060-8589, Japan
| | - Mayumi Tsuchiya
- Research Faculty of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo, 060-8589, Japan
| | - Sae Fukushima
- Research Faculty of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo, 060-8589, Japan
| | - Jun Abe
- Research Faculty of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo, 060-8589, Japan
| | - Akira Kanazawa
- Research Faculty of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo, 060-8589, Japan.
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Hawkins LJ, Al-Attar R, Storey KB. Transcriptional regulation of metabolism in disease: From transcription factors to epigenetics. PeerJ 2018; 6:e5062. [PMID: 29922517 PMCID: PMC6005171 DOI: 10.7717/peerj.5062] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 06/04/2018] [Indexed: 12/13/2022] Open
Abstract
Every cell in an individual has largely the same genomic sequence and yet cells in different tissues can present widely different phenotypes. This variation arises because each cell expresses a specific subset of genomic instructions. Control over which instructions, or genes, are expressed is largely controlled by transcriptional regulatory pathways. Each cell must assimilate a huge amount of environmental input, and thus it is of no surprise that transcription is regulated by many intertwining mechanisms. This large regulatory landscape means there are ample possibilities for problems to arise, which in a medical context means the development of disease states. Metabolism within the cell, and more broadly, affects and is affected by transcriptional regulation. Metabolism can therefore contribute to improper transcriptional programming, or pathogenic metabolism can be the result of transcriptional dysregulation. Here, we discuss the established and emerging mechanisms for controling transcription and how they affect metabolism in the context of pathogenesis. Cis- and trans-regulatory elements, microRNA and epigenetic mechanisms such as DNA and histone methylation, all have input into what genes are transcribed. Each has also been implicated in diseases such as metabolic syndrome, various forms of diabetes, and cancer. In this review, we discuss the current understanding of these areas and highlight some natural models that may inspire future therapeutics.
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Affiliation(s)
- Liam J Hawkins
- Institute of Biochemistry, Department of Biology, Carleton University, Ottawa, ON, Canada
| | - Rasha Al-Attar
- Institute of Biochemistry, Department of Biology, Carleton University, Ottawa, ON, Canada
| | - Kenneth B Storey
- Institute of Biochemistry, Department of Biology, Carleton University, Ottawa, ON, Canada
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Conde J, Otero M, Scotece M, Abella V, Gómez R, López V, Pino J, Mera A, Goldring MB, Gualillo O. E74-Like Factor (ELF3) and Leptin, a Novel Loop Between Obesity and Inflammation Perpetuating a Pro-Catabolic State in Cartilage. Cell Physiol Biochem 2018; 45:2401-2410. [PMID: 29550824 DOI: 10.1159/000488227] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Accepted: 01/30/2018] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS The E74-like factor 3 (ELF3) is an inflammatory mediator that participates in cartilage destruction in osteoarthritis. Leptin and other adipokines negatively impact articular cartilage, triggering catabolic and inflammatory responses in chondrocytes. Here, we investigated whether leptin induces ELF3 expression in chondrocytes and the signaling pathway involved in this process. METHODS We determined mRNA and protein levels of ELF3 by RT-qPCR and Western blotting using cultured human primary chondrocytes and the human T/C-28a2 chondrocyte cell line. Further, we measured luciferase activities of different reporter constructs, and we assessed the contribution of leptin to the induction of ELF3 mRNA by knocking down hLEPR gene expression using siRNA technology. RESULTS Leptin synergizes with IL-1β in inducing ELF3 expression in chondrocytes. We also found that PI3K, p38, and JAK2 signaling pathways are at play in the leptin-driven induction of ELF3. Moreover, we confirm the participation of NFΚB in the leptin/IL-1β synergistic induction of ELF3. CONCLUSION Here we show, for the first time, the regulation of ELF3 expression by leptin, suggesting that this transcription factor likely mediates the inflammatory responses triggered by leptin in articular chondrocytes.
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Affiliation(s)
- Javier Conde
- SERGAS, Santiago University Clinical Hospital, NEIRID Lab (NeuroEndocrine Interaction in Rheumatology and Inflammatory Diseases), Institute of Medical Research (IDIS), Building C, Level-2, Santiago de Compostela, Spain
| | - Miguel Otero
- Orthopaedic Soft Tissue Research Program, The Hospital for Special Surgery, and Department of Cell and Developmental Biology, Weill Cornell Medical College, New York, New York, USA
| | - Morena Scotece
- SERGAS, Santiago University Clinical Hospital, NEIRID Lab (NeuroEndocrine Interaction in Rheumatology and Inflammatory Diseases), Institute of Medical Research (IDIS), Building C, Level-2, Santiago de Compostela, Spain
| | - Vanessa Abella
- SERGAS, Santiago University Clinical Hospital, NEIRID Lab (NeuroEndocrine Interaction in Rheumatology and Inflammatory Diseases), Institute of Medical Research (IDIS), Building C, Level-2, Santiago de Compostela, Spain
| | - Rodolfo Gómez
- Musculoskeletal Pathology Laboratory, Institute IDIS, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Verónica López
- SERGAS, Santiago University Clinical Hospital, NEIRID Lab (NeuroEndocrine Interaction in Rheumatology and Inflammatory Diseases), Institute of Medical Research (IDIS), Building C, Level-2, Santiago de Compostela, Spain
| | - Jesús Pino
- SERGAS, Santiago University Clinical Hospital, Division of Orthopaedic Surgery and Traumatology, Santiago de Compostela, Spain
| | - Antonio Mera
- SERGAS (Servizo Galego de Saude), Division of Rheumatology, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Mary B Goldring
- Orthopaedic Soft Tissue Research Program, The Hospital for Special Surgery, and Department of Cell and Developmental Biology, Weill Cornell Medical College, New York, New York, USA
| | - Oreste Gualillo
- SERGAS, Santiago University Clinical Hospital, NEIRID Lab (NeuroEndocrine Interaction in Rheumatology and Inflammatory Diseases), Institute of Medical Research (IDIS), Building C, Level-2, Santiago de Compostela, Spain
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Abstract
Breast cancer is a collection of distinct tumor subtypes that are driven by unique gene expression profiles. These transcriptomes are controlled by various epigenetic marks that dictate which genes are expressed and suppressed. During carcinogenesis, extensive restructuring of the epigenome occurs, including aberrant acetylation, alteration of methylation patterns, and accumulation of epigenetic readers at oncogenes. As epigenetic alterations are reversible, epigenome-modulating drugs could provide a mechanism to silence numerous oncogenes simultaneously. Here, we review the impact of inhibitors of the Bromodomain and Extraterminal (BET) family of epigenetic readers in breast cancer. These agents, including the prototypical BET inhibitor JQ1, have been shown to suppress a variety of oncogenic pathways while inducing minimal, if any, toxicity in models of several subtypes of breast cancer. BET inhibitors also synergize with multiple approved anti-cancer drugs, providing a greater response in breast cancer cell lines and mouse models than either single agent. The combined findings of the studies discussed here provide an excellent rationale for the continued investigation of the utility of BET inhibitors in breast cancer.
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Affiliation(s)
- Jennifer M Sahni
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH 44106, United States
| | - Ruth A Keri
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH 44106, United States; Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH 44106, United States; Department of General Medical Sciences-Oncology, Case Western Reserve University, Cleveland, OH 44106, United States.
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29
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Abstract
MicroRNAs (miRNAs) are important short endogenous non-coding RNAs that have critical biological roles by acting as post-transcriptional regulators of gene expression. Chromosomal region 9q22.32 encodes the miR-23b/27b/24-1 cluster and produces miR-23b, which is a pleiotropic modulator in many developmental processes and pathological conditions. Expression of miR-23b is actively suppressed and induced in response to many different stimuli. We discuss the biological functions and transcriptional regulation of this multifaceted miRNA in different tumor types, during development, upon viral infection, as well as in various clinical disorders, immune responses, as well as cardiovascular and thyroid functions. The combined body of work suggests that miR-23b expression is modulated by a diverse array of stimuli in cells from different lineages and participates in multiple gene regulatory feedback loops. Elevation of miR-23b levels appears to instruct cells to limit their proliferative and migratory potential, while promoting the acquisition of specialized phenotypes or protection from invading viruses and parasites. In contrast, loss of miR-23b can deregulate normal tissue homeostasis by removing constraints on cell cycle progression and cell motility. Collectively, the findings on miR-23b indicate that it is a very potent post-transcriptional regulator of growth and differentiation during development, multiple cancers and other biological processes. Understanding the regulation and activity of miR-23b has significant diagnostic value in many biological disorders and may identify cellular pathways that are amenable to therapeutic intervention.
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Affiliation(s)
- Wei Wang
- Department of Orthopeadics, Pu Ai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, China; Department of Orthopedic Surgery & Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | - Yuji Wang
- Department of Orthopedic Surgery & Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA; Department of Orthopaedics, Changzhou No. 2 People's Hospital, Nanjing Medical University, 29 Xinglong Alley, Jiangsu, China
| | - Weijun Liu
- Department of Orthopeadics, Pu Ai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei, China
| | - Andre J van Wijnen
- Department of Orthopedic Surgery & Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA.
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30
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Ingham VA, Pignatelli P, Moore JD, Wagstaff S, Ranson H. The transcription factor Maf-S regulates metabolic resistance to insecticides in the malaria vector Anopheles gambiae. BMC Genomics 2017; 18:669. [PMID: 28854876 PMCID: PMC5577768 DOI: 10.1186/s12864-017-4086-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 08/24/2017] [Indexed: 11/16/2022] Open
Abstract
Background Malaria control in Africa is dependent upon the use insecticides but intensive use of a limited number of chemicals has led to resistance in mosquito populations. Increased production of enzymes that detoxify insecticides is one of the most potent resistance mechanisms. Several metabolic enzymes have been implicated in insecticide resistance but the processes controlling their expression have remained largely elusive. Results Here, we show that the transcription factor Maf-S regulates expression of multiple detoxification genes, including the key insecticide metabolisers CYP6M2 and GSTD1 in the African malaria vector Anopheles gambiae. Attenuation of this transcription factor through RNAi induced knockdown reduced transcript levels of these effectors and significantly increased mortality after exposure to the pyrethroid insecticides and DDT (permethrin: 9.2% to 19.2% (p = 0.015), deltamethrin: 3.9% to 21.6% (p = 0.036) and DDT: 1% to 11.7% (p = <0.01), whilst dramatically decreasing mortality induced by the organophosphate malathion (79.6% to 8.0% (p = <0.01)). Additional genes regulated by Maf-S were also identified providing new insight into the role of this transcription factor in insects. Conclusion Maf-S is a key regulator of detoxification genes in Anopheles mosquitoes. Disrupting this transcription factor has opposing effects on the mosquito’s response to different insecticide classes providing a mechanistic explanation to the negative cross resistance that has been reported between pyrethroids and organophosphates. Electronic supplementary material The online version of this article (10.1186/s12864-017-4086-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Victoria A Ingham
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, England, L35QA.
| | - Patricia Pignatelli
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, England, L35QA
| | - Jonathan D Moore
- Earlham Institute, Norwich Research Park Innovation Centre, Colney Lane, Norwich, England, NR4 7UH
| | - Simon Wagstaff
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, England, L35QA
| | - Hilary Ranson
- Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, England, L35QA.
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31
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Abstract
Protocols have been established that direct differentiation of human pluripotent stem cells into a variety of cell types, including the endoderm and its derivatives. This model of differentiation has been useful for investigating the molecular mechanisms that guide human developmental processes. Using a directed differentiation protocol combined with shRNA depletion we sought to understand the role of GATA6 in regulating the earliest switch from pluripotency to definitive endoderm. We reveal that GATA6 depletion during endoderm formation results in apoptosis of nascent endoderm cells, concomitant with a loss of endoderm gene expression. We show by chromatin immunoprecipitation followed by DNA sequencing that GATA6 directly binds to several genes encoding transcription factors that are necessary for endoderm differentiation. Our data support the view that GATA6 is a central regulator of the formation of human definitive endoderm from pluripotent stem cells by directly controlling endoderm gene expression. Summary: Using the differentiation of huESCs as a model for endoderm formation, we reveal that the transcription factor GATA6 regulates the onset of endoderm gene expression and is required for its viability.
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Affiliation(s)
- J B Fisher
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA.,Blood Center of Wisconsin, Milwaukee, WI 53226, USA
| | - K Pulakanti
- Blood Center of Wisconsin, Milwaukee, WI 53226, USA
| | - S Rao
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA.,Blood Center of Wisconsin, Milwaukee, WI 53226, USA.,Division of Pediatric Hematology, Oncology, and Blood and Marrow Transplant, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - S A Duncan
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA .,Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC 29425, USA
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32
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Wu Z, Wang L, Xu X, Lin G, Mao H, Ran X, Zhang T, Huang K, Wang H, Huang Q, Xu Q, Hu C. Interaction of IRF9 and STAT2 synergistically up-regulates IFN and PKR transcription in Ctenopharyngodon idella. Mol Immunol 2017; 85:273-282. [PMID: 28347954 DOI: 10.1016/j.molimm.2017.03.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 03/10/2017] [Indexed: 02/01/2023]
Abstract
IRF9 is a key factor in the JAK-STAT pathway. Under the stimulation of type I IFN, IRF9 interacts with STAT1 and STAT2 to form the IFN-I-stimulated gene factor 3 (ISGF3) which activates the transcription of ISG. However, many studies also showed that the dimmer IRF9/STAT2 rather than the tripolymer IRF9/STAT1/STAT2 acts as the ISGF3 in cells in response to IFN signals. In the present study, the full-length cDNA sequence of IRF9 (termed CiIRF9, KT601055) and STAT2 (term CiSTAT2, KT781914) from grass carp were cloned and identified. A low level of constitutive expression of CiIRF9 was detected by RT-PCR in grass carp tissues, but it was significantly up-regulated by LPS and poly I:C stimulation. In vitro, a high-affinity interaction between CiIRF9 and the promoter of CiIFN or CiPKR was demonstrated by gel mobility shift assay. In vivo, the promoter activities of CiIFN and CiPKR were not only increased by transient transfection of CiIRF9, but also prominently increased by co-transfection of CiIRF9 and CiSTAT2. Moreover, the interaction of CiIRF9 and CiSTAT2 was further investigated by in vivo and in vitro protein interaction assays. Recombinant CiIRF9 and CiSTAT2, both tagged with FLAG (or HA), were expressed in HEK 293T cells by transient transfection experiment. Co-immunoprecipitation assays showed that CiIRF9 can interact with CiSTAT2 in vivo. Soluble GST-ST2-936 (containing the N-terminal and coiled-coil domain of CiSTAT2) was expressed and purified from E. coli. A GST pull-down assay suggested that GST-tagged ST2-936 efficiently bound to FLAG-tagged IRF9. The data indicated that interaction of IRF9 and STAT2 synergistically up-regulated the transcriptional level of IFN and ISG genes.
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Affiliation(s)
- Zhen Wu
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Liqiang Wang
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Xiaowen Xu
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Gang Lin
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Huiling Mao
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Xiaoqin Ran
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Tao Zhang
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Keyi Huang
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Haizhou Wang
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Qingli Huang
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Qun Xu
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China
| | - Chengyu Hu
- College of Life Science, Key Lab of Aquatic Resources and Utilization of Jiangxi Province, Nanchang University, Nanchang 330031, China.
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33
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Guo QL, Su HF, Wang N, Liao SR, Lu YT, Ou TM, Tan JH, Li D, Huang ZS. Synthesis and evaluation of 7-substituted-5,6-dihydrobenzo[c]acridine derivatives as new c-KIT promoter G-quadruplex binding ligands. Eur J Med Chem 2017; 130:458-71. [PMID: 28284084 DOI: 10.1016/j.ejmech.2017.02.051] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 02/18/2017] [Accepted: 02/20/2017] [Indexed: 11/21/2022]
Abstract
It has been shown that treatment of cancer cells with c-KIT G-quadruplex binding ligands can reduce their c-KIT expression levels thus inhibiting cell proliferation and inducing cell apoptosis. Herein, a series of new 7-substituted-5,6-dihydrobenzo[c]acridine derivatives were designed and synthesized. Subsequent biophysical evaluation demonstrated that the derivatives could effectively bind to and stabilize c-KIT G-quadruplex with good selectivity against duplex DNA. It was found that 12-N-methylated derivatives with a positive charge introduced at 12-position of 5,6-dihydrobenzo[c]acridine ring had similar binding affinity but lower stabilizing ability to c-KIT G-quadruplex DNA, compared with those of nonmethylated derivatives. Further molecular modeling studies showed possible binding modes of G-quadruplex with the ligands. RT-PCR assay and Western blot showed that compound 2b suppressed transcription and translation of c-KIT gene in K562 cells, which was consistent with the property of an effective G-quadruplex binding ligand targeting c-KIT oncogene promoter. Further biological evaluation showed that compound 2b could induce apoptosis through activation of the caspase-3 cascade pathway.
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Wang X, Zhang T, Mao H, Mi Y, Zhong B, Wei L, Liu X, Hu C. Grass carp (Ctenopharyngodon idella) ATF6 (activating transcription factor 6) modulates the transcriptional level of GRP78 and GRP94 in CIK cells. Fish Shellfish Immunol 2016; 52:65-73. [PMID: 26988288 DOI: 10.1016/j.fsi.2016.03.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Revised: 03/14/2016] [Accepted: 03/14/2016] [Indexed: 06/05/2023]
Abstract
ATF transcription factors are stress proteins containing alkaline area-leucine zipper and play an important role in endoplasmic reticulum stress. ATF6 is a protective protein which regulates the adaptation of cells to ER stress by modulating the transcription of UPR (Unfolded Protein Response) target genes, including GRP78 and GRP94. In the present study, a grass carp (Ctenopharyngodon idella) ATF6 full-length cDNA (named CiATF6, KT279356) has been cloned and identified. CiATF6 is 4176 bp in length, comprising 159 nucleotides of 5'-untranslated sequence, a 1947 nucleotides open reading frame and 2170 nucleotides of 3'-untranslated sequences. The largest open reading frame of CiATF6 translates into 648 aa with a typical DNA binding domain (BRLZ domain) and shares significant homology to the known ATF6 counterparts. Phylogenetic reconstruction confirmed its closer evolutionary relationship with other fish counterparts, especially with Zebrafish ATF6. RT-PCR showed that CiATF6 was ubiquitously expressed and significantly up-regulated after stimulation with thermal stress in all tested grass carp tissues. In order to know more about the role of CiATF6 in ER stress, recombinant CiATF6N with His-tag was over-expressed in Rosetta Escherichia coli, and the expressed protein was purified by affinity chromatography with Ni-NTA His-Bind Resin. In vitro, gel mobility shift assays were employed to analyze the interaction of CiATF6 protein with the promoters of grass carp GRP78 and GRP94, respectively. The result has shown that CiATF6 could bind to these promoters with high affinity by means of its BRLZ mainly. To further study the transcriptional regulatory mechanism of CiATF6, Dual-luciferase reporter assays were applied. Recombinant plasmids of pGL3-GRP78P and pGL3-CiGRP94P were constructed and transiently co-transfected with pcDNA3.1-CiATF6 (pcDN3.1-CiATF6-nBRLZ, respectively) into C. idella kidney (CIK) cells. The result has shown that CiATF6 could activate CiGRP78 and CiGRP94 promoters.
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Affiliation(s)
- Xiangqin Wang
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang, 330031, China
| | - Tao Zhang
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang, 330031, China
| | - Huiling Mao
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang, 330031, China.
| | - Yichuan Mi
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang, 330031, China
| | - Bin Zhong
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang, 330031, China
| | - Lili Wei
- Jiangxi Agricultural University, Nanchang, 330045, China
| | - Xiancheng Liu
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang, 330031, China
| | - Chengyu Hu
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang, 330031, China.
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35
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Abstract
The insight that the genomic control of developmental process is encoded in the form of gene regulatory networks has profound impacts on many areas of modern bioscience. Most importantly, it affects developmental biology itself, as it means that a causal understanding of development requires knowledge of the architecture of regulatory network interactions. Furthermore, it follows that functional changes in developmental gene regulatory networks have to be considered as a primary mechanism for evolutionary process. We here discuss some of the recent advances in gene regulatory network biology and how they have affected our current understanding of development, evolution, and regulatory genomics.
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Affiliation(s)
- Isabelle S Peter
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA.
| | - Eric H Davidson
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California, USA
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36
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Xu X, Lai Q, Gu M, Liu D, Hou Q, Liu X, Mi Y, Sun Z, Wang H, Lin G, Hu C. Fish IRF3 up-regulates the transcriptional level of IRF1, IRF2, IRF3 and IRF7 in CIK cells. Fish Shellfish Immunol 2015; 47:978-985. [PMID: 26545324 DOI: 10.1016/j.fsi.2015.10.039] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 10/24/2015] [Accepted: 10/27/2015] [Indexed: 06/05/2023]
Abstract
Interferon Regulatory Factors (IRFs) belong to a family of transcription factor involved in transcriptional regulation of type I IFN and IFN-stimulated genes (ISG) in cells. In the present study, an IRF3 full-length cDNA (termed CiIRF3, JX999055) and its promoter sequence were cloned by homology cloning strategy and genome walking from grass carp (Ctenopharyngodon idella). The full-length cDNA sequence of CiIRF3 is comprised of a 5'UTR (195 bp), a 3'UTR (269 bp) and a largest open reading frame (ORF) of 1377 bp encoding a polypeptide of 458 amino acids. CiIRF3 has a conservative DNA-binding domain (DBD) at N-terminal and a relatively conserved interferon regulatory factors association domain (IAD). Phylogenetic tree analysis indicated that CiIRF3 gathers together with other IRF-3 from higher vertebrates in the same branch. The promoter sequence of CiIRF3 (596 bp) consists of three IRF-E, a C/EBP beta, a NF-kappa B and a TATA-BOX. CiIRF3 was constitutively expressed at low level in different grass carp tissues but was rapidly up-regulated with Poly I:C stimulation. To study the molecular mechanism of CiIRF3 regulating the transcription of IRFs, CiIRF3 was expressed in Escherichia coli BL21 and purified by affinity chromatography with the Ni-NTA His-Bind Resin. Gel mobility shift assays revealed the affinity of CiIRF3 protein with promoters of CiIRF1, CiIRF2, CiIRF3 and CiIRF7 respectively. Then, CIK cells were co-transfected with pcDNA3.1-CiIRF3, pGL3-promotor (pGL3-CiIRF1, pGL3-CiIRF2, pGL3-CiIRF3, pGL3-CiIRF7) and luciferase reporter vector respectively. The cotransfection experiment showed that CiIRF3 increased the promoter activity of CiIRF1, CiIRF2, CiIRF3 and CiIRF7. Furthermore, overexpression of CiIRF3 in CIK cells also up-regulated the expressions of CiIRF1, CiIRF2, CiIRF3 and CiIRF7. So, CiIRF3 can improve the transcriptional level of CiIRF1, CiIRF2, CiIRF3 and CiIRF7.
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Affiliation(s)
- Xiaowen Xu
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China
| | - Qinan Lai
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China; Infectious Diseases Hospital of Nanchang University, Nanchang 330006, Jiangxi Province, China
| | - Meihui Gu
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China
| | - Dan Liu
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China
| | - Qunhao Hou
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China
| | - Xiancheng Liu
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China
| | - Yichuan Mi
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China
| | - Zhicheng Sun
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China
| | - Haizhou Wang
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China
| | - Gang Lin
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China
| | - Chengyu Hu
- Department of Bioscience, College of Life Science, Nanchang University, Nanchang 330031, China.
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Regneri J, Volff JN, Schartl M. Transcriptional control analyses of the Xiphophorus melanoma oncogene. Comp Biochem Physiol C Toxicol Pharmacol 2015; 178:116-127. [PMID: 26348392 PMCID: PMC4662873 DOI: 10.1016/j.cbpc.2015.09.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 08/25/2015] [Accepted: 09/01/2015] [Indexed: 02/07/2023]
Abstract
Melanoma development in interspecific hybrids of Xiphophorus is induced by the overexpression of the mutationally activated receptor tyrosine kinase Xmrk in pigment cells. Based on the melanocyte specificity of the transcriptional upregulation, a pigment cell-specific promoter region was postulated for xmrk, the activity of which is controlled in healthy purebred fish by the molecularly still unidentified regulator locus R. However, as yet the xmrk promoter region is still poorly characterized. In order to contribute to a better understanding of xmrk expression regulation, we performed a functional analysis of the entire putative gene regulatory region of the oncogene using conventional plasmid-based reporter systems as well as a newly established method employing BAC-derived luciferase reporter constructs in melanoma and non-melanoma cell lines. Using the melanocyte-specific mitfa promoter as control, we could demonstrate that our in vitro system is able to reliably monitor regulation of transcription through cell type-specific regulatory sequences. We found that sequences within 200kb flanking the xmrk oncogene do not lead to any specific transcriptional activation in melanoma compared to control cells. Hence, xmrk reporter constructs fail to faithfully reproduce the endogenous transcriptional regulation of the oncogene. Our data therefore strongly indicate that the melanocyte-specific transcription of xmrk is not the consequence of pigment cell-specific cis-regulatory elements in the promoter region. This hints at additional regulatory mechanisms involved in transcriptional control of the oncogene, thereby suggesting a key role for epigenetic mechanisms in oncogenic xmrk overexpression and thereby in tumor development in Xiphophorus.
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Affiliation(s)
- Janine Regneri
- Physiological Chemistry, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany
| | - Jean-Nicolas Volff
- Institut de Génomique Fonctionelle de Lyon, Ecole Normale Supérieure de Lyon, 46, allée d'Italie, 69364 Lyon cedex 07, France
| | - Manfred Schartl
- Physiological Chemistry, Biocenter, University of Würzburg, Am Hubland, Würzburg, Germany; Comprehensive Cancer Center Mainfranken, University Clinic Würzburg, Würzburg, Germany.
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Morgan RK, Batra H, Gaerig VC, Hockings J, Brooks TA. Identification and characterization of a new G-quadruplex forming region within the kRAS promoter as a transcriptional regulator. Biochim Biophys Acta 2015; 1859:235-45. [PMID: 26597160 DOI: 10.1016/j.bbagrm.2015.11.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 11/13/2015] [Accepted: 11/17/2015] [Indexed: 10/22/2022]
Abstract
kRAS is one of the most prevalent oncogenic aberrations. It is either upregulated or mutationally activated in a multitude of cancers, including pancreatic, lung, and colon cancers. While a significant effort has been made to develop drugs that target kRAS, their clinical activity has been disappointing due to a variety of mechanistic hurdles. The presented works describe a novel mechanism and molecular target to downregulate kRAS expression--a previously undescribed G-quadruplex (G4) secondary structure within the proximal promoter acting as a transcriptional silencer. There are three distinct guanine-rich regions within the core kRAS promoter, including a previously examined region (G4near). Of these regions, the most distal region does not form an inducible and stable structure, whereas the two more proximal regions (termed near and mid) do form strong G4s. G4near is predominantly a tri-stacked structure with a discontinuous guanine run incorporated; G4mid consists of seven distinct runs of continuous guanines and forms numerous competing isoforms, including a stable three-tetrad stacked mixed parallel and antiparallel loop structures with longer loops of up to 10 nucleotides. Comprehensive analysis of the regulation of transcription by higher order structures has revealed that the guanine-rich region in the middle of the core promoter, termed G4mid, is a stronger repressor of promoter activity than G4near. Using the extensive guanine-rich region of the kRAS core promoter, and particularly the G4mid structure, as the primary target, future drug discovery programs will have potential to develop a potent, specifically targeted small molecule to be used in the treatment of pancreatic, ovarian, lung, and colon cancers.
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Affiliation(s)
- Rhianna K Morgan
- School of Pharmacy, Department of BioMolecular Sciences, Division of Pharmacology, University of Mississippi, University, MS 38677, USA
| | - Harshul Batra
- School of Pharmacy, Department of BioMolecular Sciences, Division of Pharmacology, University of Mississippi, University, MS 38677, USA
| | - Vanessa C Gaerig
- College of Pharmacy, Department of Pharmacology and Toxicology, The University of Arizona, Tucson, AZ 85721, USA
| | - Jennifer Hockings
- School of Pharmacy, Department of BioMolecular Sciences, Division of Pharmacology, University of Mississippi, University, MS 38677, USA
| | - Tracy A Brooks
- School of Pharmacy, Department of BioMolecular Sciences, Division of Pharmacology, University of Mississippi, University, MS 38677, USA.
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Alves MS, Soares ZG, Vidigal PMP, Barros EG, Poddanosqui AMP, Aoyagi LN, Abdelnoor RV, Marcelino-Guimarães FC, Fietto LG. Differential expression of four soybean bZIP genes during Phakopsora pachyrhizi infection. Funct Integr Genomics 2015; 15:685-96. [PMID: 26013145 DOI: 10.1007/s10142-015-0445-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 05/07/2015] [Accepted: 05/18/2015] [Indexed: 11/26/2022]
Abstract
Asian soybean rust (ASR), caused by the obligate biotrophic fungus Phakopsora pachyrhizi, is one of most important diseases in the soybean (Glycine max (L.) Merr.) agribusiness. The identification and characterization of genes related to plant defense responses to fungal infection are essential to develop ASR-resistant plants. In this work, we describe four soybean genes, GmbZIP62, GmbZIP105, GmbZIPE1, and GmbZIPE2, which encode transcription factors containing a basic leucine zipper (bZIP) domain from two divergent classes, and that are responsive to P. pachyrhizi infection. Molecular phylogenetic analyses demonstrated that these genes encode proteins similar to bZIP factors responsive to pathogens. Yeast transactivation assays showed that only GmbZIP62 has strong transactivation activity in yeast. In addition, three of the bZIP transcription factors analyzed were also differentially expressed by plant defense hormones, and all were differentially expressed by fungal attack, indicating that these proteins might participate in response to ASR infection. The results suggested that these bZIP proteins are part of the plant defense response to P. pachyrhizi infection, by regulating the gene expression related to ASR infection responses. These bZIP genes are potential targets to obtain new soybean genotypes resistant to ASR.
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Affiliation(s)
- Murilo S Alves
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-000, Brazil
| | - Zamira G Soares
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-000, Brazil
| | - Pedro M P Vidigal
- Núcleo de Análise de Biomoléculas, NuBioMol, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-000, Brazil
| | - Everaldo G Barros
- Universidade Católica de Brasília, 70790-160, Brasília, Distrito Federal, Brazil
| | | | | | | | | | - Luciano G Fietto
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-000, Brazil.
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40
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Alves MS, Soares ZG, Vidigal PMP, Barros EG, Poddanosqui AMP, Aoyagi LN, Abdelnoor RV, Marcelino-Guimarães FC, Fietto LG. Differential expression of four soybean bZIP genes during Phakopsora pachyrhizi infection. Funct Integr Genomics 2015. [PMID: 26013145 DOI: 10.1007/s10142-015-0445-440] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2023]
Abstract
Asian soybean rust (ASR), caused by the obligate biotrophic fungus Phakopsora pachyrhizi, is one of most important diseases in the soybean (Glycine max (L.) Merr.) agribusiness. The identification and characterization of genes related to plant defense responses to fungal infection are essential to develop ASR-resistant plants. In this work, we describe four soybean genes, GmbZIP62, GmbZIP105, GmbZIPE1, and GmbZIPE2, which encode transcription factors containing a basic leucine zipper (bZIP) domain from two divergent classes, and that are responsive to P. pachyrhizi infection. Molecular phylogenetic analyses demonstrated that these genes encode proteins similar to bZIP factors responsive to pathogens. Yeast transactivation assays showed that only GmbZIP62 has strong transactivation activity in yeast. In addition, three of the bZIP transcription factors analyzed were also differentially expressed by plant defense hormones, and all were differentially expressed by fungal attack, indicating that these proteins might participate in response to ASR infection. The results suggested that these bZIP proteins are part of the plant defense response to P. pachyrhizi infection, by regulating the gene expression related to ASR infection responses. These bZIP genes are potential targets to obtain new soybean genotypes resistant to ASR.
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Affiliation(s)
- Murilo S Alves
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-000, Brazil
| | - Zamira G Soares
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-000, Brazil
| | - Pedro M P Vidigal
- Núcleo de Análise de Biomoléculas, NuBioMol, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-000, Brazil
| | - Everaldo G Barros
- Universidade Católica de Brasília, 70790-160, Brasília, Distrito Federal, Brazil
| | | | | | | | | | - Luciano G Fietto
- Departamento de Bioquímica e Biologia Molecular, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36570-000, Brazil.
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Kim J, Kim KM, Noh JH, Yoon JH, Abdelmohsen K, Gorospe M. Long noncoding RNAs in diseases of aging. Biochim Biophys Acta 2015; 1859:209-21. [PMID: 26141605 DOI: 10.1016/j.bbagrm.2015.06.013] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 06/13/2015] [Accepted: 06/24/2015] [Indexed: 12/22/2022]
Abstract
Aging is a process during which progressive deteriorating of cells, tissues, and organs over time lead to loss of function, disease, and death. Towards the goal of extending human health span, there is escalating interest in understanding the mechanisms that govern aging-associated pathologies. Adequate regulation of expression of coding and noncoding genes is critical for maintaining organism homeostasis and preventing disease processes. Long noncoding RNAs (lncRNAs) are increasingly recognized as key regulators of gene expression at all levels--transcriptional, post-transcriptional and post-translational. In this review, we discuss our emerging understanding of lncRNAs implicated in aging illnesses. We focus on diseases arising from age-driven impairment in energy metabolism (obesity, diabetes), the declining capacity to respond homeostatically to proliferative and damaging stimuli (cancer, immune dysfunction), and neurodegeneration. We identify the lncRNAs involved in these ailments and discuss the rising interest in lncRNAs as diagnostic and therapeutic targets to ameliorate age-associated pathologies and prolong health. This article is part of a Special Issue entitled: Clues to long noncoding RNA taxonomy1, edited by Dr. Tetsuro Hirose and Dr. Shinichi Nakagawa.
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Affiliation(s)
- Jiyoung Kim
- Laboratory of Genetics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Kyoung Mi Kim
- Laboratory of Genetics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Ji Heon Noh
- Laboratory of Genetics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Je-Hyun Yoon
- Laboratory of Genetics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA
| | - Kotb Abdelmohsen
- Laboratory of Genetics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA.
| | - Myriam Gorospe
- Laboratory of Genetics, National Institute on Aging-Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, USA.
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Mukai M, Hira S, Nakamura K, Nakamura S, Kimura H, Sato M, Kobayashi S. H3K36 Trimethylation-Mediated Epigenetic Regulation is Activated by Bam and Promotes Germ Cell Differentiation During Early Oogenesis in Drosophila. Biol Open 2015; 4:119-24. [PMID: 25572421 PMCID: PMC4365480 DOI: 10.1242/bio.201410850] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Epigenetic silencing is critical for maintaining germline stem cells in Drosophila ovaries. However, it remains unclear how the differentiation factor, Bag-of-marbles (Bam), counteracts transcriptional silencing. We found that the trimethylation of lysine 36 on histone H3 (H3K36me3), a modification that is associated with gene activation, is enhanced in Bam-expressing cells. H3K36me3 levels were reduced in flies deficient in Bam. Inactivation of the Set2 methyltransferase, which confers the H3K36me3 modification, in germline cells markedly reduced H3K36me3 and impaired differentiation. Genetic analyses revealed that Set2 acts downstream of Bam. Furthermore, orb expression, which is required for germ cell differentiation, was activated by Set2, probably through direct H3K36me3 modification of the orb locus. Our data indicate that H3K36me3-mediated epigenetic regulation is activated by bam, and that this modification facilitates germ cell differentiation, probably through transcriptional activation. This work provides a novel link between Bam and epigenetic transcriptional control.
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Affiliation(s)
- Masanori Mukai
- Department of Biology, Faculty of Science and Engineering, Konan University, Okamoto, Higashinada, Kobe 658-8501, Japan Graduate School of Natural Science, Konan University, Okamoto, Higashinada, Kobe 658-8501, Japan Institute for Integrative Neurobiology, Konan University, Okamoto, Higashinada, Kobe 658-8501, Japan
| | - Seiji Hira
- Graduate School of Natural Science, Konan University, Okamoto, Higashinada, Kobe 658-8501, Japan Research Fellow of Japan Society for the Promotion of Science, Tokyo 102-0083, Japan
| | - Katsuhiro Nakamura
- Graduate School of Natural Science, Konan University, Okamoto, Higashinada, Kobe 658-8501, Japan
| | - Shoichi Nakamura
- Department of Biology, Faculty of Science and Engineering, Konan University, Okamoto, Higashinada, Kobe 658-8501, Japan
| | - Hiroshi Kimura
- Department of Biological Sciences, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, 226-8501, Japan
| | - Masanao Sato
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, Higashiyama, Myodaiji, Okazaki 444-8787, Japan
| | - Satoru Kobayashi
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, National Institutes of Natural Sciences, Higashiyama, Myodaiji, Okazaki 444-8787, Japan Life Science Center, Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
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Hale MA, Swift GH, Hoang CQ, Deering TG, Masui T, Lee YK, Xue J, MacDonald RJ. The nuclear hormone receptor family member NR5A2 controls aspects of multipotent progenitor cell formation and acinar differentiation during pancreatic organogenesis. Development 2014; 141:3123-33. [PMID: 25063451 DOI: 10.1242/dev.109405] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The orphan nuclear receptor NR5A2 is necessary for the stem-like properties of the epiblast of the pre-gastrulation embryo and for cellular and physiological homeostasis of endoderm-derived organs postnatally. Using conditional gene inactivation, we show that Nr5a2 also plays crucial regulatory roles during organogenesis. During the formation of the pancreas, Nr5a2 is necessary for the expansion of the nascent pancreatic epithelium, for the subsequent formation of the multipotent progenitor cell (MPC) population that gives rise to pre-acinar cells and bipotent cells with ductal and islet endocrine potential, and for the formation and differentiation of acinar cells. At birth, the NR5A2-deficient pancreas has defects in all three epithelial tissues: a partial loss of endocrine cells, a disrupted ductal tree and a >90% deficit of acini. The acinar defects are due to a combination of fewer MPCs, deficient allocation of those MPCs to pre-acinar fate, disruption of acinar morphogenesis and incomplete acinar cell differentiation. NR5A2 controls these developmental processes directly as well as through regulatory interactions with other pancreatic transcriptional regulators, including PTF1A, MYC, GATA4, FOXA2, RBPJL and MIST1 (BHLHA15). In particular, Nr5a2 and Ptf1a establish mutually reinforcing regulatory interactions and collaborate to control developmentally regulated pancreatic genes by binding to shared transcriptional regulatory regions. At the final stage of acinar cell development, the absence of NR5A2 affects the expression of Ptf1a and its acinar specific partner Rbpjl, so that the few acinar cells that form do not complete differentiation. Nr5a2 controls several temporally distinct stages of pancreatic development that involve regulatory mechanisms relevant to pancreatic oncogenesis and the maintenance of the exocrine phenotype.
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Affiliation(s)
- Michael A Hale
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
| | - Galvin H Swift
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
| | - Chinh Q Hoang
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
| | - Tye G Deering
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
| | - Toshi Masui
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
| | - Youn-Kyoung Lee
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9041, USA
| | - Jumin Xue
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
| | - Raymond J MacDonald
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
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Hoffmann SA, Hos D, Küspert M, Lang RA, Lovell-Badge R, Wegner M, Reiprich S. Stem cell factor Sox2 and its close relative Sox3 have differentiation functions in oligodendrocytes. Development 2014; 141:39-50. [PMID: 24257626 PMCID: PMC3865748 DOI: 10.1242/dev.098418] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 09/29/2013] [Indexed: 11/20/2022]
Abstract
Neural precursor cells of the ventricular zone give rise to all neurons and glia of the central nervous system and rely for maintenance of their precursor characteristics on the closely related SoxB1 transcription factors Sox1, Sox2 and Sox3. We show in mouse spinal cord that, whereas SoxB1 proteins are usually downregulated upon neuronal specification, they continue to be expressed in glial precursors. In the oligodendrocyte lineage, Sox2 and Sox3 remain present into the early phases of terminal differentiation. Surprisingly, their deletion does not alter precursor characteristics but interferes with proper differentiation. Although a direct influence on myelin gene expression may be part of their function, we provide evidence for another mode of action. SoxB1 proteins promote oligodendrocyte differentiation in part by negatively controlling miR145 and thereby preventing this microRNA from inhibiting several pro-differentiation factors. This study presents one of the few cases in which SoxB1 proteins, including the stem cell factor Sox2, are associated with differentiation rather than precursor functions.
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Affiliation(s)
- Stephanie A. Hoffmann
- Institut für Biochemie, Emil-Fischer-Zentrum, Universität Erlangen-Nürnberg, D-91054 Erlangen, Germany
| | - Deniz Hos
- Institut für Biochemie, Emil-Fischer-Zentrum, Universität Erlangen-Nürnberg, D-91054 Erlangen, Germany
| | - Melanie Küspert
- Institut für Biochemie, Emil-Fischer-Zentrum, Universität Erlangen-Nürnberg, D-91054 Erlangen, Germany
| | - Richard A. Lang
- Division of Pediatric Ophthalmology, Cincinnati Children’s Hospital Research Foundation, Cincinnati, OH 45229-3026, USA
| | | | - Michael Wegner
- Institut für Biochemie, Emil-Fischer-Zentrum, Universität Erlangen-Nürnberg, D-91054 Erlangen, Germany
| | - Simone Reiprich
- Institut für Biochemie, Emil-Fischer-Zentrum, Universität Erlangen-Nürnberg, D-91054 Erlangen, Germany
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Misra JR, Lam G, Thummel CS. Constitutive activation of the Nrf2/Keap1 pathway in insecticide-resistant strains of Drosophila. Insect Biochem Mol Biol 2013; 43:1116-24. [PMID: 24099738 PMCID: PMC3852162 DOI: 10.1016/j.ibmb.2013.09.005] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 09/20/2013] [Accepted: 09/23/2013] [Indexed: 05/13/2023]
Abstract
Pesticide resistance poses a major challenge for the control of vector-borne human diseases and agricultural crop protection. Although a number of studies have defined how mutations in specific target proteins can lead to insecticide resistance, much less is known about the mechanisms by which constitutive overexpression of detoxifying enzymes contributes to metabolic pesticide resistance. Here we show that the Nrf2/Keap1 pathway is constitutively active in two laboratory-selected DDT-resistant strains of Drosophila, 91R and RDDTR, leading to the overexpression of multiple detoxifying genes. Disruption of the Drosophila Nrf2 ortholog, CncC, or overexpression of Keap1, is sufficient to block this transcriptional response. In addition, a CncC-responsive reporter is highly active in both DDT-resistant strains and this response is dependent on the presence of an intact CncC binding site in the promoter. Microarray analysis revealed that ∼20% of the genes differentially expressed in the 91R strain are known CncC target genes. Finally, we show that CncC is partially active in these strains, consistent with the fitness cost associated with constitutive activation of the pathway. This study demonstrates that the Nrf2/Keap1 pathway contributes to the widespread overexpression of detoxification genes in insecticide-resistant strains and raises the possibility that inhibitors of this pathway could provide effective synergists for insect population control.
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Misra JR, Lam G, Thummel CS. Constitutive activation of the Nrf2/Keap1 pathway in insecticide-resistant strains of Drosophila. Insect Biochem Mol Biol 2013; 43:1116-1124. [PMID: 24099738 DOI: 10.1016/jjbmb.2013.09.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 09/20/2013] [Accepted: 09/23/2013] [Indexed: 05/24/2023]
Abstract
Pesticide resistance poses a major challenge for the control of vector-borne human diseases and agricultural crop protection. Although a number of studies have defined how mutations in specific target proteins can lead to insecticide resistance, much less is known about the mechanisms by which constitutive overexpression of detoxifying enzymes contributes to metabolic pesticide resistance. Here we show that the Nrf2/Keap1 pathway is constitutively active in two laboratory-selected DDT-resistant strains of Drosophila, 91R and RDDTR, leading to the overexpression of multiple detoxifying genes. Disruption of the Drosophila Nrf2 ortholog, CncC, or overexpression of Keap1, is sufficient to block this transcriptional response. In addition, a CncC-responsive reporter is highly active in both DDT-resistant strains and this response is dependent on the presence of an intact CncC binding site in the promoter. Microarray analysis revealed that ∼20% of the genes differentially expressed in the 91R strain are known CncC target genes. Finally, we show that CncC is partially active in these strains, consistent with the fitness cost associated with constitutive activation of the pathway. This study demonstrates that the Nrf2/Keap1 pathway contributes to the widespread overexpression of detoxification genes in insecticide-resistant strains and raises the possibility that inhibitors of this pathway could provide effective synergists for insect population control.
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Affiliation(s)
- Jyoti R Misra
- Department of Human Genetics, University of Utah School of Medicine, 15 North 2030 East, Room 2100, Salt Lake City, UT 84112-5330, USA
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Hložková K, Suman J, Strnad H, Ruml T, Paces V, Kotrba P. Characterization of pbt genes conferring increased Pb2+ and Cd2+ tolerance upon Achromobacter xylosoxidans A8. Res Microbiol 2013; 164:1009-18. [PMID: 24125695 DOI: 10.1016/j.resmic.2013.10.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 09/03/2013] [Indexed: 10/26/2022]
Abstract
The cluster of pbtTFYRABC genes is carried by plasmid pA81. Its elimination from Achromobacter xylosoxidans A8 resulted in increased sensitivity towards Pb(2+) and Cd(2+). Predicted pbtTRABC products share strong similarities with Pb(2+) uptake transporter PbrT, transcriptional regulator PbrR, metal efflux P1-ATPases PbrA and CadA, undecaprenyl pyrophosphatase PbrB and its signal peptidase PbrC from Cupriavidus metallidurans CH34. Expression of pbtABC or pbtA in a metal-sensitive Escherichia coli GG48 rendered the strain Pb(2+)-, Cd(2+)- and Zn(2+)-tolerant and caused decreased accumulation of the metal ions. Accumulation of Pb(2+), but not of Cd(2+) or Zn(2+), was promoted in E. coli expressing pbtT. Additional genes of the pbt cluster are pbtF and pbtY, which encode the cation diffusion facilitator (CDF)-like transporter and a putative fatty acid hydroxylase of unknown function, respectively. Expression of pbtF did not confer increased metal tolerance upon E. coli GG48, although the protein showed measurable Pb(2+)-efflux activity. Unlike the pbtT promoter, promoters of pbtABC, pbtF and pbtY contain features characteristic of promoters controlled by metal-responsive transcriptional regulators of the MerR family. Upregulation of pbtABC, pbtF and pbtY upon Pb(2+), Cd(2+) and Zn(2+) exposure was confirmed in wild-type Achromobacter xylosoxidans A8. Gel shift assays proved binding of purified PbtR to the respective promoters.
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Affiliation(s)
- Kateřina Hložková
- Department of Biochemistry and Microbiology, Institute of Chemical Technology, Prague, Technická 3, CZ-166 28 Prague, Czech Republic.
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Abstract
DNA methylation is a type of epigenetic modification in the human genome, which means that gene expression is regulated without altering the DNA sequence. Methylation and the relationship between methylation and cancer have been the focus of molecular biology researches. Methylation represses gene expression and can influence embryogenesis and tumorigenesis. In different tissues and at different stages of life, the level of methylation of DNA varies, implying a fundamental but distinct role for methylation. When genes are repressed by abnormal methylation, the resulting effects can include instability of that gene and inactivation of a tumor suppressor gene. MicroRNAs have some aspects in common with this regulation of gene expression. Here we reviewed the influence of gene methylation on cancer and analyzed the methods used to profile methylation. We also assessed the correlation between methylation and other epigenetic modifications and microRNAs. About 55 845 research papers have been published about methylation, and one-fifth of these are about the appearance of methylation in cancer. We conclude that methylation does play a role in some cancer types.
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