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Costa SRD, Monteiro MDC, da Silva Júnior FMR, Sandrini JZ. Methylene blue toxicity in zebrafish cell line is dependent on light exposure. Cell Biol Int 2016; 40:895-905. [PMID: 27238358 DOI: 10.1002/cbin.10629] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 05/20/2016] [Indexed: 12/12/2022]
Abstract
Methylene blue (MB) has been widely applied in the clinical area and is currently being used in aquaculture as biocide. Some recent studies have emphasized the importance of understanding the action mechanism and the MB cellular targets. In this sense, zebrafish is considered a relevant model to study the intrinsic pathway of apoptosis as well as the cellular responses involving DNA damage and repair. So, the aim of the present study was to compare MB action mechanisms in a zebrafish cell line, both in the absence (MB alone; dark toxicity) and in the presence of photosynthetically active radiation (MB+PAR; phototoxicity). There was a significant increase of the levels of reactive oxygen and nitrogen species 3 h after MB treatment, whereas this increase was only observed 12 h after treatment with MB+PAR. All treatments with MB resulted in an increase in DNA damage after 3 and 6 h. However, cell death by apoptosis was observed from 6 h after treatment with MB+PAR and 12 h after treatment with MB alone. The expression of genes related to apoptosis was altered after MB and MB+PAR treatment. Therefore, this zebrafish cell line is sensitive to the photodynamic action of MB; MB is able to generate DNA damage and induce apoptosis in this cell line both alone and in the presence of PAR. However, the pathways leading to apoptosis in this model appear to be dependent on the type of MB exposure (in the presence or absence of PAR).
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Affiliation(s)
- Simone Rutz da Costa
- Programa de Pós-Graduação em Ciências Fisiológicas-Fisiologia Animal Comparada, Universidade Federal do Rio Grande-FURG, Av. Itália km 8, 96203-900, Rio Grande, Rio Grande do Sul, Brazil
| | - Mauricio da Costa Monteiro
- Programa de Pós-Graduação em Ciências Fisiológicas-Fisiologia Animal Comparada, Universidade Federal do Rio Grande-FURG, Av. Itália km 8, 96203-900, Rio Grande, Rio Grande do Sul, Brazil
| | | | - Juliana Zomer Sandrini
- Programa de Pós-Graduação em Ciências Fisiológicas-Fisiologia Animal Comparada, Universidade Federal do Rio Grande-FURG, Av. Itália km 8, 96203-900, Rio Grande, Rio Grande do Sul, Brazil.,Instituto de Ciências Biológicas, Universidade Federal do Rio Grande-FURG, Av. Itália km 8, 96203-900, Rio Grande, Rio Grande do Sul, Brazil
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Abstract
The mitochondrion descends from a bacterium that, about two billion years ago, became endosymbiotic. This organelle represents a Pandora’s box whose opening triggers cytochrome-c release and apoptosis of cells from multicellular animals, which evolved much later, about six hundred million years ago. BCL-2 proteins, which are critical apoptosis regulators, were recruited at a certain time point in evolution to either lock or unlock this mitochondrial Pandora’s box. Hence, particularly intriguing is the issue of when and how the “BCL-2 proteins–mitochondria–apoptosis” triptych emerged. This chapter explains what it takes from an evolutionary perspective to evolve a BCL-2-regulated apoptotic pathway, by focusing on the events occurring upstream of mitochondria.
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Pei Y, Lu X, He L, Wang H, Zhang A, Li Y, Huang R, Liao L, Zhu Z, Wang Y. Expression pattern and transcriptional regulatory mechanism of noxa gene in grass carp (Ctenopharyngodon idella). FISH & SHELLFISH IMMUNOLOGY 2015; 47:861-867. [PMID: 26453794 DOI: 10.1016/j.fsi.2015.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 09/30/2015] [Accepted: 10/02/2015] [Indexed: 06/05/2023]
Abstract
Noxa, a pro-apoptotic protein, plays an important role in cell apoptosis. The researches about noxa gene were concentrated in mammalians, whereas the role and transcriptional regulatory mechanism of noxa in fish were still unclear. In this study, the expression pattern and transcriptional regulatory mechanism of noxa gene in grass carp were analyzed. Noxa was constitutively expressed in all the examined tissues but the relative expression level differed. After exposure to grass carp reovirus (GCRV), mRNA expression level of noxa was down-regulated at the early phase whereas up-regulated at the late phase of infection. Luciferase assays showed that the promoter region -867 ∼ +107 of noxa had high activity and the region -678 ∼ -603 was important in the response to GCRV infection. By deleting the predicted transcription factor binding sites, transcription factors FOXO1 and CEBPβ were found important for noxa in response to GCRV infection. Moreover, the noxa promoter was biotin-labeled and incubated with nuclear extracts from GCRV infected cells. Mass spectrometry analysis showed that transcription factors FOXO1 and CEBPβ were also enriched in the combined proteins. Therefore, the results suggested that transcription factors FOXO1 and CEBPβ may play an important role in the regulation of noxa. Our study would provide new insight into the transcriptional regulatory mechanism of noxa in teleost fish.
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Affiliation(s)
- Yongyan Pei
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaonan Lu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Libo He
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Hao Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Aidi Zhang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yongming Li
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Rong Huang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Lanjie Liao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Zuoyan Zhu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yaping Wang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
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54
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Zhou R, Zhang H, Wang Z, Zhou X, Si J, Gan L, Li J, Liu Y. The developmental toxicity and apoptosis in zebrafish eyes induced by carbon-ion irradiation. Life Sci 2015; 139:114-22. [DOI: 10.1016/j.lfs.2015.08.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 07/28/2015] [Accepted: 08/17/2015] [Indexed: 01/08/2023]
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Abstract
Zebrafish (Danio rerio) have been extensively used to study apoptotic cell death during normal development and under a wide range of experimental manipulations. A number of features make zebrafish a particularly powerful model organism: (1) embryos are small in size, develop rapidly outside the mother, and are optically transparent; (2) tools are readily available for rapid knockdown and overexpression of genes; and (3) embryos can be arrayed into multiwell plates and are permeable to a wide range of drugs and small molecules. The molecular machinery underlying the intrinsic and extrinsic apoptosis pathways appears to be highly conserved between zebrafish and mammals. In this chapter, techniques are described for detecting apoptotic cells in situ in both fixed and live zebrafish embryos. Methods for inducing and inhibiting apoptosis and for functionally manipulating genes involved in apoptotic signaling are also discussed.
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56
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Popgeorgiev N, Prudent J, Bonneau B, Gillet G. The yolk cell of the zebrafish blastula harbors functional apoptosis machinery. Commun Integr Biol 2014. [DOI: 10.4161/cib.16697] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Gioacchini G, Dalla Valle L, Benato F, Fimia GM, Nardacci R, Ciccosanti F, Piacentini M, Borini A, Carnevali O. Interplay between autophagy and apoptosis in the development of Danio rerio follicles and the effects of a probiotic. Reprod Fertil Dev 2014. [PMID: 23195281 DOI: 10.1071/rd12187] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The present study investigated autophagic processes in Danio rerio preovulatory follicles (Stage III and IV). There were more autophagosomes, as revealed by electron microscopy, in follicles from females fed the probiotic Lactobacillus rhamnosus IMC 501. This was confirmed by increased expression of genes involved in the autophagic process, namely ambra1, becn1, lc3 and uvrag. In addition, preovulatory follicles from females fed the probiotic contained more microtubule-associated protein 1 light chain 3 isoform II (LC3-II) and less p62 protein. The increased autophagy in preovulatory follicles from females fed the probiotic was concomitant with a decrease in the apoptotic process in the ovary, as evidenced by terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling analysis and confirmed by lower expression of genes involved in apoptosis (i.e., p53, bax, apaf and cas3) and higher expression as igfII and igf1r. The results of the present study provide preliminary evidence of the involvement of autophagy during follicle development in the zebrafish ovary. In addition, we have demonstrated for the first time that a functional food, such as L. rhamnosus IMC 501, can modulate the balance between apoptosis and autophagy that regulates ovary physiology in zebrafish by inhibiting follicular apoptosis and improving follicular survival.
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Affiliation(s)
- Giorgia Gioacchini
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Via Brecce Bianche, 60131, Ancona, Italy
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58
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Prudent J, Popgeorgiev N, Bonneau B, Thibaut J, Gadet R, Lopez J, Gonzalo P, Rimokh R, Manon S, Houart C, Herbomel P, Aouacheria A, Gillet G. Bcl-wav and the mitochondrial calcium uniporter drive gastrula morphogenesis in zebrafish. Nat Commun 2014; 4:2330. [PMID: 23942336 DOI: 10.1038/ncomms3330] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 07/18/2013] [Indexed: 02/07/2023] Open
Abstract
Bcl-2 proteins are acknowledged as key regulators of programmed cell death. However, increasing data suggest additional roles, including regulation of the cell cycle, metabolism and cytoskeletal dynamics. Here we report the discovery and characterization of a new Bcl-2-related multidomain apoptosis accelerator, Bcl-wav, found in fish and frogs. Genetic and molecular studies in zebrafish indicate that Bcl-wav and the recently identified mitochondrial calcium uniporter (MCU) contribute to the formation of the notochord axis by controlling blastomere convergence and extension movements during gastrulation. Furthermore, we found that Bcl-wav controls intracellular Ca(2+) trafficking by acting on the mitochondrial voltage-dependent anion channel, and possibly on MCU, with direct consequences on actin microfilament dynamics and blastomere migration guidance. Thus, from an evolutionary point of view, the original function of Bcl-2 proteins might have been to contribute in controlling the global positioning system of blastomeres during gastrulation, a critical step in metazoan development.
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Affiliation(s)
- Julien Prudent
- Université de Lyon, Centre de recherche en cancérologie de Lyon, U1052 INSERM, UMS 3453 CNRS, Université Lyon I, Centre Léon Bérard, 28 rue Laennec, Lyon 69008, France
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59
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Kotkamp K, Kur E, Wendik B, Polok BK, Ben-Dor S, Onichtchouk D, Driever W. Pou5f1/Oct4 promotes cell survival via direct activation of mych expression during zebrafish gastrulation. PLoS One 2014; 9:e92356. [PMID: 24643012 PMCID: PMC3958507 DOI: 10.1371/journal.pone.0092356] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 02/17/2014] [Indexed: 01/29/2023] Open
Abstract
Myc proteins control cell proliferation, cell cycle progression, and apoptosis, and play important roles in cancer as well in establishment of pluripotency. Here we investigated the control of myc gene expression by the Pou5f1/Oct4 pluripotency factor in the early zebrafish embryo. We analyzed the expression of all known zebrafish Myc family members, myca, mycb, mych, mycl1a, mycl1b, and mycn, by whole mount in situ hybridization during blastula and gastrula stages in wildtype and maternal plus zygotic pou5f1 mutant (MZspg) embryos, as well as by quantitative PCR and in time series microarray data. We found that the broad blastula and gastrula stage mych expression, as well as late gastrula stage mycl1b expression, both depend on Pou5f1 activity. We analyzed ChIP-Seq data and found that both Pou5f1 and Sox2 bind to mych and mycl1b control regions. The regulation of mych by Pou5f1 appears to be direct transcriptional activation, as overexpression of a Pou5f1 activator fusion protein in MZspg embryos induced strong mych expression even when translation of zygotically expressed mRNAs was suppressed. We further showed that MZspg embryos develop enhanced apoptosis already during early gastrula stages, when apoptosis was not be detected in wildtype embryos. However, Mych knockdown alone did not induce early apoptosis, suggesting potentially redundant action of several early expressed myc genes, or combination of several pathways affected in MZspg. Experimental mych overexpression in MZspg embryos did significantly, but not completely suppress the apoptosis phenotype. Similarly, p53 knockdown only partially suppressed apoptosis in MZspg gastrula embryos. However, combined knockdown of p53 and overexpression of Mych completely rescued the MZspg apoptosis phenotype. These results reveal that Mych has anti-apoptotic activity in the early zebrafish embryo, and that p53-dependent and Myc pathways are likely to act in parallel to control apoptosis at these stages.
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Affiliation(s)
- Kay Kotkamp
- Developmental Biology, Institute Biology I, Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Esther Kur
- Developmental Biology, Institute Biology I, Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Björn Wendik
- Developmental Biology, Institute Biology I, Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Bożena K. Polok
- Developmental Biology, Institute Biology I, Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Shifra Ben-Dor
- Biological Services, Weizmann Institute of Science, Rehovot, Israel
| | - Daria Onichtchouk
- Developmental Biology, Institute Biology I, Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
- BIOSS - Centre for Biological Signalling Studies, Freiburg, Germany
| | - Wolfgang Driever
- Developmental Biology, Institute Biology I, Faculty of Biology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
- BIOSS - Centre for Biological Signalling Studies, Freiburg, Germany
- * E-mail:
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60
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Zebrafish Noxa promotes mitosis in early embryonic development and regulates apoptosis in subsequent embryogenesis. Cell Death Differ 2014; 21:1013-24. [PMID: 24608793 PMCID: PMC4013518 DOI: 10.1038/cdd.2014.22] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 01/02/2014] [Accepted: 01/20/2014] [Indexed: 01/16/2023] Open
Abstract
Noxa functions in apoptosis and immune system of vertebrates, but its activities in embryo development remain unclear. In this study, we have studied the role of zebrafish Noxa (zNoxa) by using zNoxa-specifc morpholino knockdown and overexpression approaches in developing zebrafish embryos. Expression pattern analysis indicates that zNoxa transcript is of maternal origin, which displays a uniform distribution in early embryonic development until shield stage, and the zygote zNoxa transcription is initiated from this stage and mainly localized in YSL of the embryos. The zNoxa expression alterations result in strong embryonic development defects, demonstrating that zNoxa regulates apoptosis from 75% epiboly stage of development onward, in which zNoxa firstly induces the expression of zBik, and then cooperates with zBik to regulate apoptosis. Moreover, zNoxa knockdown also causes a reduction in number of mitotic cells before 8 h.p.f., suggesting that zNoxa also promotes mitosis before 75% epiboly stage. The effect of zNoxa on mitosis is mediated by zWnt4b in early embryos, whereas zMcl1a and zMcl1b suppress the ability of zNoxa to regulate mitosis and apoptosis at different developmental stages. In addition, mammalian mouse Noxa (mNoxa) mRNA was demonstrated to rescue the arrest of mitosis when zNoxa was knocked down, suggesting that mouse and zebrafish Noxa might have similar dual functions. Therefore, the current findings indicate that Noxa is a novel regulator of early mitosis before 75% epiboly stage when it translates into a key mediator of apoptosis in subsequent embryogenesis.
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61
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Toruno C, Carbonneau S, Stewart RA, Jette C. Interdependence of Bad and Puma during ionizing-radiation-induced apoptosis. PLoS One 2014; 9:e88151. [PMID: 24516599 PMCID: PMC3916415 DOI: 10.1371/journal.pone.0088151] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 01/05/2014] [Indexed: 11/19/2022] Open
Abstract
Ionizing radiation (IR)-induced DNA double-strand breaks trigger an extensive cellular signaling response that involves the coordination of hundreds of proteins to regulate DNA repair, cell cycle arrest and apoptotic pathways. The cellular outcome often depends on the level of DNA damage as well as the particular cell type. Proliferating zebrafish embryonic neurons are highly sensitive to IR-induced apoptosis, and both p53 and its transcriptional target puma are essential mediators of the response. The BH3-only protein Puma has previously been reported to activate mitochondrial apoptosis through direct interaction with the pro-apoptotic Bcl-2 family proteins Bax and Bak, thus constituting the role of an “activator” BH3-only protein. This distinguishes it from BH3-only proteins like Bad that are thought to indirectly promote apoptosis through binding to anti-apoptotic Bcl-2 family members, thereby preventing the sequestration of activator BH3-only proteins and allowing them to directly interact with and activate Bax and Bak. We have shown previously that overexpression of the BH3-only protein Bad in zebrafish embryos supports normal embryonic development but greatly sensitizes developing neurons to IR-induced apoptosis. While Bad has previously been shown to play only a minor role in promoting IR-induced apoptosis of T cells in mice, we demonstrate that Bad is essential for robust IR-induced apoptosis in zebrafish embryonic neural tissue. Moreover, we found that both p53 and Puma are required for Bad-mediated radiosensitization in vivo. Our findings show the existence of a hierarchical interdependence between Bad and Puma whereby Bad functions as an essential sensitizer and Puma as an essential activator of IR-induced mitochondrial apoptosis specifically in embryonic neural tissue.
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Affiliation(s)
- Cristhian Toruno
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Seth Carbonneau
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Rodney A. Stewart
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Cicely Jette
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
- * E-mail:
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62
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Sorrells S, Toruno C, Stewart RA, Jette C. Analysis of apoptosis in zebrafish embryos by whole-mount immunofluorescence to detect activated Caspase 3. J Vis Exp 2013:e51060. [PMID: 24378359 PMCID: PMC4109746 DOI: 10.3791/51060] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Whole-mount immunofluorescence to detect activated Caspase 3 (Casp3 assay) is useful to identify cells undergoing either intrinsic or extrinsic apoptosis in zebrafish embryos. The whole-mount analysis provides spatial information in regard to tissue specificity of apoptosing cells, although sectioning and/or colabeling is ultimately required to pinpoint the exact cell types undergoing apoptosis. The whole-mount Casp3 assay is optimized for analysis of fixed embryos between the 4-cell stage and 32 hr-post-fertilization and is useful for a number of applications, including analysis of zebrafish mutants and morphants, overexpression of mutant and wild-type mRNAs, and exposure to chemicals. Compared to acridine orange staining, which can identify apoptotic cells in live embryos in a matter of hours, Casp3 and TUNEL assays take considerably longer to complete (2-4 days). However, because of the dynamic nature of apoptotic cell formation and clearance, analysis of fixed embryos ensures accurate comparison of apoptotic cells across multiple samples at specific time points. We have also found the Casp3 assay to be superior to analysis of apoptotic cells by the whole-mount TUNEL assay in regard to cost and reliability. Overall, the Casp3 assay represents a robust, highly reproducible assay in which to analyze apoptotic cells in early zebrafish embryos.
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63
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Lin HJ, Lee SH, Wu JL, Duann YF, Chen JY. Development of Cre-loxP technology in zebrafish to study the regulation of fish reproduction. FISH PHYSIOLOGY AND BIOCHEMISTRY 2013; 39:1525-1539. [PMID: 23670400 DOI: 10.1007/s10695-013-9806-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 05/08/2013] [Indexed: 06/02/2023]
Abstract
One cannot seek permission to market transgenic fish mainly because there is no field test or any basic research on technological developments for evaluating their biosafety. Infertility is a necessary adjunct to exploiting transgenic fish unless completely secure land-locked facilities are available. In this study, we report the generation of a Cre transgenic zebrafish line using a cytomegalovirus promoter. We also produced fish carrying the Bax1 and Bax2 plasmids; these genes were separated by two loxP sites under a zona pellucida C promoter or were driven by an anti-Müllerian hormone promoter. We inserted a red fluorescent protein gene between the two loxP sites. After obtaining transgenic lines with the two transgenic fish crossed with each other (Cre transgenic zebrafish x loxP transgenic zebrafish), the floxed DNA was found to be specifically eliminated from the female or male zebrafish, and apoptosis gene expressions caused ovarian and testicular growth cessation and degeneration. Overexpression of the Bax1 and Bax2 genes caused various expression levels of apoptosis-related genes. Accordingly, this transgenic zebrafish model system provides a method to produce infertile fish and may be useful for application to genetically modified fish.
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Affiliation(s)
- Heng-Ju Lin
- Graduate Institute of Engineering Technology-Doctoral, National Taipei University of Technology, 1 Chung-Hsiao E. Rd., Sec. 3, Taipei, 10608, Taiwan
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64
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Hu ZY, Zhang QY, Qin W, Tong JW, Zhao Q, Han Y, Meng J, Zhang JP. Gene miles-apart is required for formation of otic vesicle and hair cells in zebrafish. Cell Death Dis 2013; 4:e900. [PMID: 24176858 PMCID: PMC3920936 DOI: 10.1038/cddis.2013.432] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 09/30/2013] [Accepted: 09/30/2013] [Indexed: 12/15/2022]
Abstract
Hearing loss is a serious burden to physical and mental health worldwide. Aberrant development and damage of hearing organs are recognized as the causes of hearing loss, the molecular mechanisms underlining these pathological processes remain elusive. Investigation of new molecular mechanisms involved in proliferation, differentiation, migration and maintenance of neuromast primordium and hair cells will contribute to better understanding of hearing loss pathology. This knowledge will enable the development of protective agents and mechanism study of drug ototoxicity. In this study, we demonstrate that the zebrafish gene miles-apart, a homolog of sphingosine-1-phosphate receptor 2 (s1pr2) in mammals, has an important role in the development of otic vesicle, neuromasts and survival of hair cells. Whole-mount in situ hybridization of embryos showed that miles-apart expression occurred mainly in the encephalic region and the somites at 24 h.p.f. (hour post fertilization), in the midbrain/hindbrain boundary, the brainstem and the pre-neuromast of lateral line at 48 h.p.f. in a strict spatiotemporal regulation. Both up- and downregulation of miles-apart led to abnormal otoliths and semicircular canals, excess or few hair cells and neuromasts, and their disarranged depositions in the lateral lines. Miles-apart (Mil) dysregulation also caused abnormal expression of hearing-associated genes, including hmx2, fgf3, fgf8a, foxi1, otop1, pax2.1 and tmieb during zebrafish organogenesis. Moreover, in larvae miles-apart gene knockdown significantly upregulated proapoptotic gene zBax2 and downregulated prosurvival gene zMcl1b; in contrast, the level of zBax2 was decreased and of zMcl1b enhanced by miles-apart overexpression. Collectively, Mil activity is linked to organization and number decision of hair cells within a neuromast, also to deposition of neuromasts and formation of otic vesicle during zebrafish organogenesis. At the larva stage, Mil as an upstream regulator of bcl-2 gene family has a role in protection of hair cells against apoptosis by promoting expression of prosurvival gene zMcl1b and suppressing proapoptotic gene zBax2.
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Affiliation(s)
- Z-y Hu
- Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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65
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Emmanouilidou A, Karetsou Z, Tzima E, Kobayashi T, Papamarcaki T. Knockdown of prothymosin α leads to apoptosis and developmental defects in zebrafish embryos. Biochem Cell Biol 2013; 91:325-32. [PMID: 24032683 DOI: 10.1139/bcb-2012-0103] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Prothymosin alpha (ProTα) is an abundant nuclear protein involved in cellular processes intricately linked to development, such as cell proliferation and apoptosis. Although it is known that ProTα inhibits the formation of apoptosome and blocks caspase-3 activity, its mechanism of function in the apoptotic machinery is still under investigation. We have studied the cellular role of ProTα by knocking down its expression in HeLa cells with small hairpin RNA (shRNA) in the absence of apoptotic stimuli. Flow cytometric analysis showed that the live cell population was significantly decreased with a concomitant increase of the apoptotic populations. To understand the physiological role of ProTα within the context of embryonic development, we knocked down the Ptmab zebrafish ortholog using 2 specific morpholino oligonucleotides. Ptmab morphants exhibited growth retardation, bended trunks, and curly tails. The frequency of occurrence of the phenotypic defects was increased in a morpholino dose-dependent manner. Co-injection of ptmaa mRNA with ptmab morpholino partially rescued the morphological defects. Immunostaining with the anti-phospho-histone H3 (pH3) antibody suggested that the abnormalities of Ptmab morphants could be due to defective cell proliferation that results in growth imbalances. TUNEL fluorescent labelling and Acridine Orange staining of the morphants showed high rates of cell death in the head and tail regions. Concomitantly, the active form of caspase-3 was detected in Ptmab morphants. Our data suggest a conserved anti-apoptotic role of ProTα between zebrafish and humans, and provide the first evidence that ProTα is important for early embryogenesis.
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Affiliation(s)
- Anastasia Emmanouilidou
- a Laboratory of Biological Chemistry, Medical School, University of Ioannina, 451 10 Ioannina, Greece
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66
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Nishiwaki Y, Yoshizawa A, Kojima Y, Oguri E, Nakamura S, Suzuki S, Yuasa-Kawada J, Kinoshita-Kawada M, Mochizuki T, Masai I. The BH3-only SNARE BNip1 mediates photoreceptor apoptosis in response to vesicular fusion defects. Dev Cell 2013; 25:374-87. [PMID: 23725763 DOI: 10.1016/j.devcel.2013.04.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 03/15/2013] [Accepted: 04/27/2013] [Indexed: 11/25/2022]
Abstract
Intracellular vesicular transport is important for photoreceptor function and maintenance. However, the mechanism underlying photoreceptor degeneration in response to vesicular transport defects is unknown. Here, we report that photoreceptors undergo apoptosis in a zebrafish β-soluble N-ethylmaleimide-sensitive factor attachment protein (β-SNAP) mutant. β-SNAP cooperates with N-ethylmaleimide-sensitive factor to recycle the SNAP receptor (SNARE), a key component of the membrane fusion machinery, by disassembling the cis-SNARE complex generated in the vesicular fusion process. We found that photoreceptor apoptosis in the β-SNAP mutant was dependent on the BH3-only protein BNip1. BNip1 functions as a component of the syntaxin-18 SNARE complex and regulates retrograde transport from the Golgi to the endoplasmic reticulum. Failure to disassemble the syntaxin-18 cis-SNARE complex caused BNip1-dependent apoptosis. These data suggest that the syntaxin-18 cis-SNARE complex functions as an alarm factor that monitors vesicular fusion competence and that BNip1 transforms vesicular fusion defects into photoreceptor apoptosis.
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Affiliation(s)
- Yuko Nishiwaki
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna, Okinawa 904-0412, Japan
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67
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Wang L, Liu T, Xu L, Gao Y, Wei Y, Duan C, Chen GQ, Lin S, Patient R, Zhang B, Hong D, Liu F. Fev regulates hematopoietic stem cell development via ERK signaling. Blood 2013; 122:367-75. [PMID: 23591790 DOI: 10.1182/blood-2012-10-462655] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Reprogramming of somatic cells to desired cell types holds great promise in regenerative medicine. However, production of transplantable hematopoietic stem cells (HSCs) in vitro by defined factors has not yet been achieved. Therefore, it is critical to fully understand the molecular mechanisms of HSC development in vivo. Here, we show that Fev, an ETS transcription factor, is a pivotal regulator of HSC development in vertebrates. In fev-deficient zebrafish embryos, the first definitive HSC population was compromised and fewer T cells were found in the thymus. Genetic and chemical analyses support a mechanism whereby Fev regulates HSC through direct regulation of ERK signaling. Blastula transplant assay demonstrates that Fev regulation of HSC development is cell autonomous. Experiments performed with purified cord blood show that fev is expressed and functions in primitive HSCs in humans, indicating its conserved role in higher vertebrates. Our data indicate that Fev-ERK signaling is essential for hemogenic endothelium-based HSC development.
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Affiliation(s)
- Lu Wang
- State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
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68
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Coffin AB, Rubel EW, Raible DW. Bax, Bcl2, and p53 differentially regulate neomycin- and gentamicin-induced hair cell death in the zebrafish lateral line. J Assoc Res Otolaryngol 2013; 14:645-59. [PMID: 23821348 DOI: 10.1007/s10162-013-0404-1] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 06/20/2013] [Indexed: 12/19/2022] Open
Abstract
Sensorineural hearing loss is a normal consequence of aging and results from a variety of extrinsic challenges such as excessive noise exposure and certain therapeutic drugs, including the aminoglycoside antibiotics. The proximal cause of hearing loss is often death of inner ear hair cells. The signaling pathways necessary for hair cell death are not fully understood and may be specific for each type of insult. In the lateral line, the closely related aminoglycoside antibiotics neomycin and gentamicin appear to kill hair cells by activating a partially overlapping suite of cell death pathways. The lateral line is a system of hair cell-containing sense organs found on the head and body of aquatic vertebrates. In the present study, we use a combination of pharmacologic and genetic manipulations to assess the contributions of p53, Bax, and Bcl2 in the death of zebrafish lateral line hair cells. Bax inhibition significantly protects hair cells from neomycin but not from gentamicin toxicity. Conversely, transgenic overexpression of Bcl2 attenuates hair cell death due to gentamicin but not neomycin, suggesting a complex interplay of pro-death and pro-survival proteins in drug-treated hair cells. p53 inhibition protects hair cells from damage due to either aminoglycoside, with more robust protection seen against gentamicin. Further experiments evaluating p53 suggest that inhibition of mitochondrial-specific p53 activity confers significant hair cell protection from either aminoglycoside. These results suggest a role for mitochondrial p53 activity in promoting hair cell death due to aminoglycosides, likely upstream of Bax and Bcl2.
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Affiliation(s)
- Allison B Coffin
- Virginia Merrill Bloedel Hearing Research Center, University of Washington, Box 357923, Seattle, WA, 98195, USA,
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69
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Presenilin1 regulates histamine neuron development and behavior in zebrafish, danio rerio. J Neurosci 2013; 33:1589-97. [PMID: 23345232 DOI: 10.1523/jneurosci.1802-12.2013] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Modulatory neurotransmitters, including the histaminergic system, are essential in mediating cognitive functions affected in Alzheimer's disease (AD). The roles of disease genes associated with AD, most importantly the presenilin1 gene (psen1), are poorly understood. We studied the role of psen1 in plasticity of the brain histaminergic system using a novel psen1 mutant zebrafish, Danio rerio. We found that in psen1(-/-) zebrafish, the histaminergic system is altered throughout life. At 7 d postfertilization (dpf) the histamine neuron number was reduced in psen1(-/-) compared with wild-type (WT) fish; at 2 months of age the histamine neuron number was at the same level as that in WT fish. In 1-year-old zebrafish, the histamine neuron number was significantly increased in psen1(-/-) fish compared with WT fish. These changes in histamine neuron number were accompanied by changes in histamine-driven behaviors. Treatment with DAPT, a γ-secretase inhibitor, similarly interfered with the development of the histaminergic neurons. We also assessed the expression of γ-secretase-regulated Notch1a mRNA and β-catenin at different time points. Notch1a mRNA level was reduced in psen1(-/-) compared with WT fish, whereas β-catenin was slightly upregulated in the hypothalamus of psen1(-/-) compared with WT fish at 7 dpf. The results reveal a life-long brain plasticity in both the structure of the histaminergic system and its functions induced by altered Notch1a activity as a consequence of psen1 mutation. The new histaminergic neurons in aging zebrafish brain may arise as a result of phenotypic plasticity or represent newly differentiated stem cells.
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70
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Foxn1 maintains thymic epithelial cells to support T-cell development via mcm2 in zebrafish. Proc Natl Acad Sci U S A 2012; 109:21040-5. [PMID: 23213226 DOI: 10.1073/pnas.1217021110] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The thymus is mainly comprised of thymic epithelial cells (TECs), which form the unique thymic epithelial microenvironment essential for intrathymic T-cell development. Foxn1, a member of the forkhead transcription factor family, is required for establishing a functional thymic rudiment. However, the molecular mechanisms underlying the function of Foxn1 are still largely unclear. Here, we show that Foxn1 functions in thymus development through Mcm2 in the zebrafish. We demonstrate that, in foxn1 knockdown embryos, the thymic rudiment is reduced and T-cell development is impaired. Genome-wide expression profiling shows that a number of genes, including some known thymopoiesis genes, are dysregulated during the initiation of the thymus primordium and immigration of T-cell progenitors to the thymus. Functional and epistatic studies show that mcm2 and cdca7 are downstream of Foxn1, and mcm2 is a direct target gene of Foxn1 in TECs. Finally, we find that the thymus defects in foxn1 and mcm2 morphants might be attributed to reduced cell proliferation rather than apoptosis. Our results reveal that the foxn1-mcm2 axis plays a central role in the genetic regulatory network controlling thymus development in zebrafish.
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71
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The stat3/socs3a pathway is a key regulator of hair cell regeneration in zebrafish. [corrected]. J Neurosci 2012; 32:10662-73. [PMID: 22855815 DOI: 10.1523/jneurosci.5785-10.2012] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
All nonmammalian vertebrates studied can regenerate inner ear mechanosensory receptors (i.e., hair cells) (Corwin and Cotanche, 1988; Lombarte et al., 1993; Baird et al., 1996), but mammals possess only a very limited capacity for regeneration after birth (Roberson and Rubel, 1994). As a result, mammals experience permanent deficiencies in hearing and balance once their inner ear hair cells are lost. The mechanisms of hair cell regeneration are poorly understood. Because the inner ear sensory epithelium is highly conserved in all vertebrates (Fritzsch et al., 2007), we chose to study hair cell regeneration mechanism in adult zebrafish, hoping the results would be transferrable to inducing hair cell regeneration in mammals. We defined the comprehensive network of genes involved in hair cell regeneration in the inner ear of adult zebrafish with the powerful transcriptional profiling technique digital gene expression, which leverages the power of next-generation sequencing ('t Hoen et al., 2008). We also identified a key pathway, stat3/socs3, and demonstrated its role in promoting hair cell regeneration through stem cell activation, cell division, and differentiation. In addition, transient pharmacological inhibition of stat3 signaling accelerated hair cell regeneration without overproducing cells. Taking other published datasets into account (Sano et al., 1999; Schebesta et al., 2006; Dierssen et al., 2008; Riehle et al., 2008; Zhu et al., 2008; Qin et al., 2009), we propose that the stat3/socs3 pathway is a key response in all tissue regeneration and thus an important therapeutic target for a broad application in tissue repair and injury healing.
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72
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Sorrells S, Carbonneau S, Harrington E, Chen AT, Hast B, Milash B, Pyati U, Major MB, Zhou Y, Zon LI, Stewart RA, Look AT, Jette C. Ccdc94 protects cells from ionizing radiation by inhibiting the expression of p53. PLoS Genet 2012; 8:e1002922. [PMID: 22952453 PMCID: PMC3431329 DOI: 10.1371/journal.pgen.1002922] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 07/13/2012] [Indexed: 01/07/2023] Open
Abstract
DNA double-strand breaks (DSBs) represent one of the most deleterious forms of DNA damage to a cell. In cancer therapy, induction of cell death by DNA DSBs by ionizing radiation (IR) and certain chemotherapies is thought to mediate the successful elimination of cancer cells. However, cancer cells often evolve to evade the cytotoxicity induced by DNA DSBs, thereby forming the basis for treatment resistance. As such, a better understanding of the DSB DNA damage response (DSB–DDR) pathway will facilitate the design of more effective strategies to overcome chemo- and radioresistance. To identify novel mechanisms that protect cells from the cytotoxic effects of DNA DSBs, we performed a forward genetic screen in zebrafish for recessive mutations that enhance the IR–induced apoptotic response. Here, we describe radiosensitizing mutation 7 (rs7), which causes a severe sensitivity of zebrafish embryonic neurons to IR–induced apoptosis and is required for the proper development of the central nervous system. The rs7 mutation disrupts the coding sequence of ccdc94, a highly conserved gene that has no previous links to the DSB–DDR pathway. We demonstrate that Ccdc94 is a functional member of the Prp19 complex and that genetic knockdown of core members of this complex causes increased sensitivity to IR–induced apoptosis. We further show that Ccdc94 and the Prp19 complex protect cells from IR–induced apoptosis by repressing the expression of p53 mRNA. In summary, we have identified a new gene regulating a dosage-sensitive response to DNA DSBs during embryonic development. Future studies in human cancer cells will determine whether pharmacological inactivation of CCDC94 reduces the threshold of the cancer cell apoptotic response. Radiation therapy and most chemotherapies elicit cancer cell death through the induction of excessive DNA damage. However, cancer cells can harbor genetic defects that confer resistance to these therapies. To identify cellular components whose targeted therapeutic inactivation could potentially enhance the sensitivity of treatment-resistant cancer cells to DNA–damaging therapies, we have chosen an unbiased genetic approach in live whole zebrafish embryos to identify genes that normally protect cells from the lethal effects of DNA damage. This approach has yielded the discovery of a novel radioprotective gene called ccdc94. Upon inactivation of ccdc94, cells become more sensitive to radiation-induced cell death. Our further analysis revealed that the Ccdc94 protein functions in the Prp19 complex, which is known to regulate gene expression and repair of damaged DNA. We found that this complex normally represses radiation-induced cell death by inhibiting the expression of the p53 gene, a critical mediator of DNA damage–induced cell death. Future experiments that inactivate Ccdc94 and Prp19 complex proteins in human cancer cells will determine if inactivation of this complex represents a novel therapeutic strategy that could increase p53 expression to enhance sensitivity to DNA damaging therapies in chemo- and radio-resistant cancer cells.
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Affiliation(s)
- Shelly Sorrells
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Seth Carbonneau
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Erik Harrington
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Aye T. Chen
- Department of Hematology/Oncology, Children's Hospital, Boston, Massachusetts, United States of America
| | - Bridgid Hast
- Department of Cell and Developmental Biology, Lineberger Comprehensive Cancer Center, Chapel Hill, North Carolina, United States of America
| | - Brett Milash
- Bioinformatics Shared Resource, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Ujwal Pyati
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Michael B. Major
- Department of Cell and Developmental Biology, Lineberger Comprehensive Cancer Center, Chapel Hill, North Carolina, United States of America
| | - Yi Zhou
- Department of Hematology/Oncology, Children's Hospital, Boston, Massachusetts, United States of America
| | - Leonard I. Zon
- Department of Hematology/Oncology, Children's Hospital, Boston, Massachusetts, United States of America
| | - Rodney A. Stewart
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - A. Thomas Look
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: (ATL); (CJ)
| | - Cicely Jette
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
- * E-mail: (ATL); (CJ)
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73
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Porreca I, De Felice E, Fagman H, Di Lauro R, Sordino P. Zebrafish bcl2l is a survival factor in thyroid development. Dev Biol 2012; 366:142-52. [DOI: 10.1016/j.ydbio.2012.04.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 03/17/2012] [Accepted: 04/04/2012] [Indexed: 10/28/2022]
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74
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Autophagy and apoptosis interplay during follicular atresia in fish ovary: a morphological and immunocytochemical study. Cell Tissue Res 2012; 347:467-78. [DOI: 10.1007/s00441-012-1327-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 01/11/2012] [Indexed: 11/30/2022]
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75
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Predominant requirement of Bax for apoptosis in HCT116 cells is determined by Mcl-1's inhibitory effect on Bak. Oncogene 2011; 31:3177-89. [PMID: 22056880 PMCID: PMC3276724 DOI: 10.1038/onc.2011.497] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The intrinsic mitochondrial apoptotic pathway acts through two core pro-apoptotic proteins Bax (Bcl2-associated X protein) and Bak (Bcl2-antagonist/killer 1). Although Bax and Bak seem to have redundant roles in apoptosis, accumulating evidence also suggests that they might not be interchangeable under certain conditions, at least in some human cell lines. Here we report the generation of Bak knockout as well as BaxBak double knockout HCT116 human colon carcinoma cells. We show that Bak is dispensable for apoptosis induced by a variety of stimuli including ABT-737 but not for fluorouracil-induced apoptosis. In addition, Bax deficiency only provides partial protection against camptothecin and cisplatin-induced apoptosis and no protection against killing by Puma or ABT-737 plus Noxa overexpression. Moreover, Bak is activated normally in response to many chemotherapeutic drugs in the presence of Bax, but remains kept in check by Mcl-1 in the absence of Bax. Our data suggest that Bax and Bak are functionally redundant, but they are counteracted by distinct anti-apoptotic Bcl-2 family proteins in different species.
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76
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Popgeorgiev N, Prudent J, Bonneau B, Gillet G. The yolk cell of the zebrafish blastula harbors functional apoptosis machinery. Commun Integr Biol 2011; 4:549-551. [PMID: 22046458 DOI: 10.4161/cib.4.5.16697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2011] [Accepted: 05/30/2011] [Indexed: 11/19/2022] Open
Abstract
We recently described the implication of the Bcl-2 related antiapoptotic Nrz protein during early zebrafish development. Nrz knock-down induces calcium-dependent cytoskeleton remodeling leading to margin constriction and premature embryo lethality. In the YSL, nrz knock-down embryos exhibit some typical features of apoptosis such as mitochondrial transmembrane potential loss and cytochrome c release. However, downstream caspase-3 activation has not been detected so far. Here, we report that the YSL contains fully functional apoptotic machinery that can activate caspase-3 following zBax ectopic expression. Furthermore, we present evidence that caspase-3 activation is actually detectable in nrz knock-down embryos when premature margin constriction is prevented.
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Affiliation(s)
- Nikolay Popgeorgiev
- CRCL U1052 INSERM; UMS 3453 CNRS-Université Lyon 1; Centre Léon Bérard; Lyon, France
| | - Julien Prudent
- CRCL U1052 INSERM; UMS 3453 CNRS-Université Lyon 1; Centre Léon Bérard; Lyon, France
| | - Benjamin Bonneau
- CRCL U1052 INSERM; UMS 3453 CNRS-Université Lyon 1; Centre Léon Bérard; Lyon, France
| | - Germain Gillet
- CRCL U1052 INSERM; UMS 3453 CNRS-Université Lyon 1; Centre Léon Bérard; Lyon, France
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77
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Liarte S, Chaves-Pozo E, Abellán E, Meseguer J, Mulero V, Canario AVM, García-Ayala A. Estrogen-responsive genes in macrophages of the bony fish gilthead seabream: a transcriptomic approach. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2011; 35:840-849. [PMID: 21420425 DOI: 10.1016/j.dci.2011.03.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Revised: 03/11/2011] [Accepted: 03/12/2011] [Indexed: 05/30/2023]
Abstract
The role of sex steroids in the modulation of fish immune responses has received little attention. Previous studies have demonstrated that 17β-estradiol (E(2)) is able to alter the response of gilthead seabream leukocytes to infectious agents. We have used suppression subtractive hybridization to identify genes upregulated by E(2) (50 ng/ml) in macrophage cultures from gilthead seabream. We isolated 393 up-regulated cDNA fragments that led to the identification of 162 candidate estrogen-responsive genes. Functional analyses revealed the presence of several enriched immune processes and molecular pathways. The E(2) up-regulation of some immune-relevant genes was further confirmed by real time RT-PCR. Bioinformatics analysis revealed the ability of E(2) to orchestrate profound alterations in the macrophage expression profile, especially immune-related processes and pathways. This is the first report on E(2)-dependent modifications of fish macrophage transcriptome and lends weight to a suggested role for estrogen in the immune system, the possible significance of which is discussed.
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Affiliation(s)
- S Liarte
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, Spain
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78
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Opitz R, Maquet E, Zoenen M, Dadhich R, Costagliola S. TSH receptor function is required for normal thyroid differentiation in zebrafish. Mol Endocrinol 2011; 25:1579-99. [PMID: 21737742 DOI: 10.1210/me.2011-0046] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
TSH is the primary physiological regulator of thyroid gland function. The effects of TSH on thyroid cells are mediated via activation of its membrane receptor [TSH receptor (TSHR)]. In this study, we examined functional thyroid differentiation in zebrafish and characterized the role of TSHR signaling during thyroid organogenesis. Cloning of a cDNA encoding zebrafish Tshr showed conservation of primary structure and functional properties between zebrafish and mammalian TSHR. In situ hybridization confirmed that the thyroid is the major site of tshr expression during zebrafish development. In addition, we identified tpo, iyd, duox, and duoxa as novel thyroid differentiation markers in zebrafish. Temporal analyses of differentiation marker expression demonstrated the induction of an early thyroid differentiation program along with thyroid budding, followed by a delayed onset of duox and duoxa expression coincident with thyroid hormone synthesis. Furthermore, comparative analyses in mouse and zebrafish revealed for the first time a thyroid-enriched expression of cell death regulators of the B-cell lymphoma 2 family during early thyroid morphogenesis. Knockdown of tshr function by morpholino microinjection into embryos did not affect early thyroid morphogenesis but caused defects in later functional differentiation. The thyroid phenotype observed in tshr morphants at later stages comprised a reduction in number and size of functional follicles, down-regulation of differentiation markers, as well as reduced thyroid transcription factor expression. A comparison of our results with phenotypes observed in mouse models of defective TSHR and cAMP signaling highlights the value of zebrafish as a model to enhance the understanding of functional differentiation in the vertebrate thyroid.
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Affiliation(s)
- Robert Opitz
- Institute of Interdisciplinary Research in Molecular Human Biology, Université Libre de Bruxelles, Brussels, Belgium
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79
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Gene expression profiling in zebrafish embryos exposed to diclofenac, an environmental toxicant. Mol Biol Rep 2011; 39:2119-28. [DOI: 10.1007/s11033-011-0959-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 05/26/2011] [Indexed: 10/18/2022]
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80
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Monteiro R, Pouget C, Patient R. The gata1/pu.1 lineage fate paradigm varies between blood populations and is modulated by tif1γ. EMBO J 2011; 30:1093-103. [PMID: 21336259 DOI: 10.1038/emboj.2011.34] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 01/03/2011] [Indexed: 02/04/2023] Open
Abstract
Lineage fate decisions underpin much of development as well as tissue homeostasis in the adult. A mechanistic paradigm for such decisions is the erythroid versus myeloid fate decision controlled by cross-antagonism between gata1 and pu.1 transcription factors. In this study, we have systematically tested this paradigm in blood-producing populations in zebrafish embryos, including the haematopoietic stem cells (HSCs), and found that it takes a different form in each population. In particular, gata1 activity varies from autostimulation to autorepression. In addition, we have added a third member to this regulatory kernel, tif1γ (transcription intermediate factor-1γ). We show that tif1γ modulates the erythroid versus myeloid fate outcomes from HSCs by differentially controlling the levels of gata1 and pu.1. By contrast, tif1γ positively regulates both gata1 and pu.1 in primitive erythroid and prodefinitive erythromyeloid progenitors. We therefore conclude that the gata1/pu.1 paradigm for lineage decisions takes different forms in different cellular contexts and is modulated by tif1γ.
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Affiliation(s)
- Rui Monteiro
- Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford University, Oxford, UK
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81
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Repression of Puma by scratch2 is required for neuronal survival during embryonic development. Cell Death Differ 2011; 18:1196-207. [PMID: 21252910 DOI: 10.1038/cdd.2010.190] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Although Snail factors promote cell survival in development and cancer, the tumor-suppressor p53 promotes apoptosis in response to stress. p53 and Snail2 act antagonistically to regulate p53 upregulated modulator of apoptosis (Puma) and cell death in hematopoietic progenitors following DNA damage. Here, we show that this relationship is conserved in the developing nervous system in which Snail genes are excluded from vertebrate neurons and they are substituted by Scratch, a related but independent neural-specific factor. The transcription of scratch2 is induced directly by p53 after DNA damage to repress puma, thereby antagonizing p53-mediated apoptosis. In addition, we show that scratch2 is required for newly differentiated neurons to survive by maintaining Puma levels low during normal embryonic development in the absence of damage. scratch2 knockdown in zebrafish embryos leads to neuronal death through the activation of the intrinsic and extrinsic apoptotic pathways. To compensate for neuronal loss, the proliferation of neuronal precursors increases in scratch2-deficient embryos, reminiscent of the activation of progenitor/stem cell proliferation after damage-induced apoptosis. Our data indicate that the regulatory loop linking p53/Puma with Scratch is active in the vertebrate nervous system, not only controlling cell death in response to damage but also during normal embryonic development.
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82
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Bresciani E, Confalonieri S, Cermenati S, Cimbro S, Foglia E, Beltrame M, Di Fiore PP, Cotelli F. Zebrafish numb and numblike are involved in primitive erythrocyte differentiation. PLoS One 2010; 5:e14296. [PMID: 21179188 PMCID: PMC3001437 DOI: 10.1371/journal.pone.0014296] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Accepted: 11/11/2010] [Indexed: 11/29/2022] Open
Abstract
Background Notch signaling is an evolutionarily conserved regulatory circuitry implicated in cell fate determination in various developmental processes including hematopoietic stem cell self-renewal and differentiation of blood lineages. Known endogenous inhibitors of Notch activity are Numb-Nb and Numblike-Nbl, which play partially redundant functions in specifying and maintaining neuronal differentiation. Nb and Nbl are expressed in most tissues including embryonic and adult hematopoietic tissues in mice and humans, suggesting possible roles for these proteins in hematopoiesis. Methodology and Principal Findings We employed zebrafish to investigate the possible functional role of Numb and Numblike during hematopoiesis, as this system allows a detailed analysis even in embryos with severe defects that would be lethal in other organisms. Here we describe that nb/nbl knockdown results in severe reduction or absence of embryonic erythrocytes in zebrafish. Interestingly, nb/nbl knocked-down embryos present severe downregulation of the erythroid transcription factor gata1. This results in erythroblasts which fail to mature and undergo apoptosis. Our results indicate that Notch activity is increased in embryos injected with nb/nbl morpholino, and we show that inhibition of Notch activation can partially rescue the hematopoietic phenotype. Conclusions and Significance Our results provide the first in vivo evidence of an involvement of Numb and Numblike in zebrafish erythroid differentiation during primitive hematopoiesis. Furthermore, we found that, at least in part, the nb/nbl morphant phenotype is due to enhanced Notch activation within hematopoietic districts, which in turn results in primitive erythroid differentiation defects.
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Affiliation(s)
- Erica Bresciani
- Dipartimento di Biologia, Università degli Studi di Milano, Milano, Italy
| | - Stefano Confalonieri
- The FIRC Institute for Molecular Oncology Foundation (IFOM) at the IFOM-IEO Campus, Milano, Italy
| | - Solei Cermenati
- Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Milano, Italy
| | - Simona Cimbro
- Dipartimento di Biologia, Università degli Studi di Milano, Milano, Italy
| | - Efrem Foglia
- Dipartimento di Biologia, Università degli Studi di Milano, Milano, Italy
| | - Monica Beltrame
- Dipartimento di Scienze Biomolecolari e Biotecnologie, Università degli Studi di Milano, Milano, Italy
| | - Pier Paolo Di Fiore
- The FIRC Institute for Molecular Oncology Foundation (IFOM) at the IFOM-IEO Campus, Milano, Italy
- European Institute of Oncology (IEO), Milano, Italy
- Dipartimento di Medicina, Chirurgia ed Odontoiatria, Università degli Studi di Milano, Milano, Italy
- * E-mail: (FC); (PPDF)
| | - Franco Cotelli
- Dipartimento di Biologia, Università degli Studi di Milano, Milano, Italy
- * E-mail: (FC); (PPDF)
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83
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Gerety SS, Wilkinson DG. Morpholino artifacts provide pitfalls and reveal a novel role for pro-apoptotic genes in hindbrain boundary development. Dev Biol 2010; 350:279-89. [PMID: 21145318 PMCID: PMC3111810 DOI: 10.1016/j.ydbio.2010.11.030] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 11/02/2010] [Accepted: 11/25/2010] [Indexed: 12/16/2022]
Abstract
Morpholino antisense oligonucleotides (MOs) are widely used as a tool to achieve loss of gene function, but many have off-target effects mediated by activation of Tp53 and associated apoptosis. Here, we re-examine our previous MO-based loss-of-function studies that had suggested that Wnt1 expressed at hindbrain boundaries in zebrafish promotes neurogenesis and inhibits boundary marker gene expression in the adjacent para-boundary regions. We find that Tp53 is highly activated and apoptosis is frequently induced by the MOs used in these studies. Co-knockdown of Tp53 rescues the decrease in proneural and neuronal marker expression, which is thus an off-target effect of MOs. While loss of gene expression can be attributed to cell loss through apoptotic cell death, surprisingly we find that the ectopic expression of hindbrain boundary markers is also dependent on Tp53 activity and its downstream apoptotic effectors. We examine whether this non-specific activation of hindbrain boundary gene expression provides insight into the endogenous mechanisms underlying boundary cell specification. We find that the pro-apoptotic Bcl genes puma and bax-a are required for hindbrain boundary marker expression, and that gain of function of the Bcl-caspase pathway leads to ectopic boundary marker expression. These data reveal a non-apoptotic role for pro-apoptotic genes in the regulation of gene expression at hindbrain boundaries. In light of these findings, we discuss the precautions needed in performing morpholino knockdowns and in interpreting the data derived from their use.
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Affiliation(s)
- Sebastian S Gerety
- Division of Developmental Neurobiology, MRC National Institute for Medical Research, London, UK
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84
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Prykhozhij SV. In the absence of Sonic hedgehog, p53 induces apoptosis and inhibits retinal cell proliferation, cell-cycle exit and differentiation in zebrafish. PLoS One 2010; 5:e13549. [PMID: 21042410 PMCID: PMC2958845 DOI: 10.1371/journal.pone.0013549] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2010] [Accepted: 09/30/2010] [Indexed: 11/25/2022] Open
Abstract
Background Sonic hedgehog (Shh) signaling regulates cell proliferation during vertebrate development via induction of cell-cycle regulator gene expression or activation of other signalling pathways, prevents cell death by an as yet unclear mechanism and is required for differentiation of retinal cell types. Thus, an unsolved question is how the same signalling molecule can regulate such distinct cell processes as proliferation, cell survival and differentiation. Methodology/Principal Findings Analysis of the zebrafish shh−/− mutant revealed that in this context p53 mediates elevated apoptosis during nervous system and retina development and interferes with retinal proliferation and differentiation. While in shh−/− mutants there is activation of p53 target genes and p53-mediated apoptosis, an increase in Hedgehog (Hh) signalling by over-expression of dominant-negative Protein Kinase A strongly decreased p53 target gene expression and apoptosis levels in shh−/− mutants. Using a novel p53 reporter transgene, I confirm that p53 is active in tissues that require Shh for cell survival. Proliferation assays revealed that loss of p53 can rescue normal cell-cycle exit and the mitotic indices in the shh−/− mutant retina at 24, 36 and 48 hpf. Moreover, generation of amacrine cells and photoreceptors was strongly enhanced in the double p53−/−shh−/− mutant retina suggesting the effect of p53 on retinal differentiation. Conclusions Loss of Shh signalling leads to the p53-dependent apoptosis in the developing nervous system and retina. Moreover, Shh-mediated control of p53 activity is required for proliferation and cell cycle exit of retinal cells as well as differentiation of amacrine cells and photoreceptors.
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Affiliation(s)
- Sergey V Prykhozhij
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.
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85
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Hu SY, Lin PY, Liao CH, Gong HY, Lin GH, Kawakami K, Wu JL. Nitroreductase-mediated gonadal dysgenesis for infertility control of genetically modified zebrafish. MARINE BIOTECHNOLOGY (NEW YORK, N.Y.) 2010; 12:569-578. [PMID: 19941022 DOI: 10.1007/s10126-009-9244-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2009] [Accepted: 09/22/2009] [Indexed: 05/28/2023]
Abstract
Genetically modified (GM) fish with desirable features such as rapid growth, disease resistance, and cold tolerance, among other traits, have been established in aquaculture. However, commercially available GM fish are restricted because of global concerns over the incomplete assessments of food safety and ecological impact. The ecological impact concerns include gene flow and escape of the GM fish, which may cause extinction of wild natural fish stocks. Infertility control is a core technology for overcoming this obstacle. Although polyploidy technology, GnRH-specific antisense RNA, and RNAi against GnRH gene expression have been used to cause infertility in fish, these approaches are not 100% reliable and are not heritable. In the present study, zebrafish was used as a model to establish an inducible platform of infertility control in GM fish. Nitroreductase, which converts metronidazole substrate into cytotoxin, was fused with EGFP and expressed specifically by oocytes in the Tg(ZP:NTR-EGFP) by a zona pellucida promoter. Through consecutive immersion of metronidazole from 28 to 42 days posthatching, oocyte-specific EGFP expression was eliminated, and atrophy of the gonads was detected by anatomical analysis. These findings reveal that oocyte-specific nitroreductase-mediated catalysis of metronidazole blocks oogenesis and leads to an undeveloped oocyte. Furthermore, oocyte cell death via apoptosis was detected by a TUNEL assay. We found that the gonadal dysgenesis induced by metronidazole resulted in activation of the ovarian killer gene bok, which is a proapoptotic gene member of the Bcl-2 family and led to infertility. These results show that oocyte-specific nitroreductase-mediated catalysis of metronidazole can cause reliable infertility in zebrafish and could potentially be used as a model for other aquaculture fish species.
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Affiliation(s)
- Shao-Yang Hu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
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86
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Nadzialek S, Pigneur LM, Wéron B, Kestemont P. Bcl-2 and Caspase 3 mRNA levels in the testes of gudgeon, Gobio gobio, exposed to ethinylestradiol (EE2). AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2010; 98:304-310. [PMID: 20356636 DOI: 10.1016/j.aquatox.2010.02.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2009] [Revised: 02/19/2010] [Accepted: 02/23/2010] [Indexed: 05/29/2023]
Abstract
Apoptosis inhibition has been reported in the male reproductive tract of teleost fish exposed to 17beta-estrogen or estrogen-like compounds. In order to understand the molecular mechanisms of cell death inhibition, this study examined 2 genes involved in the apoptotic pathway, Bcl-2 and Caspase 3, an anti-apoptotic and a pro-apoptotic genes, respectively. Partial cDNA sequences of Bcl-2 and Caspase 3 were cloned from gudgeon (Gobio gobio), a common European cyprinid fish. To follow mRNA levels of Bcl-2 and Caspase 3 under xenoestrogen exposure, we first performed an in vitro experiment on fish testis exposed to the most potent xenoestrogen found in the environment, ethinylestradiol (EE2). We further studied mRNA expression of both genes in the testis of fish exposed to xenoestrogens in situ. In the in vitro experiment, fragments of gudgeon testis were exposed for 21 days to 10(-3), 10(-2), 10(-1), 1 and 10 microg/L of EE2, as well as to positive (10(-1) microg/L of E2) and ethanol control medium. Results showed a significant induction of Bcl-2 mRNA at 10(-1) microg/L (p<0.05). Surprisingly, Caspase 3, a cell death effector, displayed the same profile as observed for the anti-apoptotic gene Bcl-2. In the experiment on wild gudgeon exposed from birth to an estrogenic sewage treatment plant effluent, the mRNA expression of Bcl-2 and Caspase 3 in feminized fish (ovotestis) was not significantly different due to high variability of expression between individuals. At the current state of knowledge on spermatogenesis disruption in teleost fish, in vitro studies seem better adapted than in situ investigations to enlighten the molecular pathway of apoptosis inhibition in testis exposed to xenoestrogens.
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Affiliation(s)
- Stéphanie Nadzialek
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium
| | - Lise-Marie Pigneur
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium
| | - Benjamin Wéron
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium
| | - Patrick Kestemont
- The University of Namur (FUNDP), Unité de Recherche en Biologie des Organismes (URBO), 61 rue de Bruxelles, B-5000 Namur, Belgium.
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87
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Zhao X, Zhao L, Tian T, Zhang Y, Tong J, Zheng X, Meng A. Interruption of cenph causes mitotic failure and embryonic death, and its haploinsufficiency suppresses cancer in zebrafish. J Biol Chem 2010; 285:27924-34. [PMID: 20573960 DOI: 10.1074/jbc.m110.136077] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Kinetochore proteins associate with centromeric DNA and spindle microtubules and play essential roles in chromosome segregation during mitosis. In this study, we uncovered a zebrafish mutant, stagnant and curly (stac), that carries the Tol2 transposon element inserted at the kinetochore protein H (cenph) locus. Mutant embryos exhibit discernible cell death as early as 20 hours postfertilization, extensive apoptosis, and upward curly tail during the pharyngula period and deform around 5 days postfertilization. The stac mutant phenotype can be rescued by cenph mRNA overexpression and mimicked by cenph knockdown with antisense morpholinos, suggesting the responsibility of cenph deficiency for stac mutants. We demonstrate that the intrinsic apoptosis pathway is hyperactivated in stac mutants and that p53 knockdown partially blocks excess apoptosis in stac mutants. Mitotic cells in stac mutants show chromosome missegregation and are usually arrested in G(2)/M phase. Furthermore, compared with wild type siblings, heterozygous stac fish develop invasive tumors at a dramatically reduced rate, suggesting a reduced cancer risk. Taken together, our findings uncover an essential role of cenph in mitosis and embryonic development and its association with tumor development.
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Affiliation(s)
- Xinyi Zhao
- Protein Science Laboratory of the Ministry of the Education, College of Life Sciences, Tsinghua University, Beijing 100084, China
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88
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Podrabsky JE, Krumschnabel G. Cell death beyond worms, flies and humans: unusual model systems for cell death research. Apoptosis 2010; 15:243-8. [DOI: 10.1007/s10495-009-0450-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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89
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Tuba1a gene expression is regulated by KLF6/7 and is necessary for CNS development and regeneration in zebrafish. Mol Cell Neurosci 2010; 43:370-83. [PMID: 20123021 DOI: 10.1016/j.mcn.2010.01.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 12/24/2009] [Accepted: 01/19/2010] [Indexed: 11/21/2022] Open
Abstract
We report that knockdown of the alpha1 tubulin isoform Tuba1a, but not the highly related Tuba1b, dramatically impedes nervous system formation during development and RGC axon regeneration following optic nerve injury in adults. Within the tuba1a promoter, a G/C-rich element was identified that is necessary for tuba1a induction during RGC differentiation and optic axon regeneration. KLF6a and 7a, which we previously reported are essential for optic axon regeneration (Veldman et al., 2007), bind this G/C-rich element and transactivate the tuba1a promoter. In vivo knockdown of KLF6a and 7a attenuate regeneration-dependent activation of the endogenous tuba1a and p27 genes. These results suggest tuba1a expression is necessary for CNS development and regeneration and that KLF6a and 7a mediate their effects, at least in part, via transcriptional control of tuba1a promoter activity.
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90
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Feng CY, Rise ML. Characterization and expression analyses of anti-apoptotic Bcl-2-like genes NR-13, Mcl-1, Bcl-X1, and Bcl-X2 in Atlantic cod (Gadus morhua). Mol Immunol 2010; 47:763-84. [DOI: 10.1016/j.molimm.2009.10.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Revised: 10/07/2009] [Accepted: 10/13/2009] [Indexed: 12/16/2022]
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91
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92
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Piñon JD, Labi V, Egle A, Villunger A. Bim and Bmf in tissue homeostasis and malignant disease. Oncogene 2009; 27 Suppl 1:S41-52. [PMID: 19641506 DOI: 10.1038/onc.2009.42] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Among all BH3-only proteins known to date, most information is available on the biological role and function of Bim (Bcl-2 interacting mediator of cell death)/BOD (Bcl-2 related ovarian death agonist), whereas little is still known about its closest relative, Bcl-2 modifying factor (Bmf). Although Bim has been implicated in the regulation of cell death induction in multiple cell types and tissues in response to a large number of stimuli, including growth factor or cytokine deprivation, calcium flux, ligation of antigen receptors on T and B cells, glucocorticoid or loss of adhesion, Bmf seems to play a more restricted role by supporting Bim in some of these cell death processes. This review aims to highlight similarities between Bim and Bmf function in apoptosis signaling and their role in normal development and disease.
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Affiliation(s)
- J D Piñon
- Laboratory for Immunological and Molecular Cancer Research, University Hospital Salzburg, Salzburg, Austria
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93
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Guillemin Y, Lalle P, Gillet G, Guerin JF, Hamamah S, Aouacheria A. Oocytes and early embryos selectively express the survival factor BCL2L10. J Mol Med (Berl) 2009; 87:923-40. [DOI: 10.1007/s00109-009-0495-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 05/26/2009] [Accepted: 05/28/2009] [Indexed: 12/01/2022]
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94
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Sakamaki K, Satou Y. Caspases: evolutionary aspects of their functions in vertebrates. JOURNAL OF FISH BIOLOGY 2009; 74:727-53. [PMID: 20735596 PMCID: PMC2779465 DOI: 10.1111/j.1095-8649.2009.02184.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Caspases (cysteine-dependent aspartyl-specific protease) belong to a family of cysteine proteases that mediate proteolytic events indispensable for biological phenomena such as cell death and inflammation. The first caspase was identified as an executioner of apoptotic cell death in the worm Caenorhabditis elegans. Additionally, a large number of caspases have been identified in various animals from sponges to vertebrates. Caspases are thought to play a pivotal role in apoptosis as an evolutionarily conserved function; however, the number of caspases that can be identified is distinct for each species. This indicates that species-specific functions or diversification of physiological roles has been cultivated through caspase evolution. Furthermore, recent studies suggest that caspases are also involved in inflammation and cellular differentiation in mammals. This review highlights vertebrate caspases in their universal and divergent functions and provides insight into the physiological roles of these molecules in animals.
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Affiliation(s)
- K Sakamaki
- Department of Animal Development and Physiology, Graduate School of Biostudies, Kyoto University, Kyoto, Japan.
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95
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Chen J, Ng SM, Chang C, Zhang Z, Bourdon JC, Lane DP, Peng J. p53 isoform delta113p53 is a p53 target gene that antagonizes p53 apoptotic activity via BclxL activation in zebrafish. Genes Dev 2009; 23:278-90. [PMID: 19204115 DOI: 10.1101/gad.1761609] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
p53 is a well-known tumor suppressor and is also involved in processes of organismal aging and developmental control. A recent exciting development in the p53 field is the discovery of various p53 isoforms. One p53 isoform is human Delta133p53 and its zebrafish counterpart Delta113p53. These N-terminal-truncated p53 isoforms are initiated from an alternative p53 promoter, but their expression regulation and physiological significance at the organismal level are not well understood. We show here that zebrafish Delta113p53 is directly transactivated by full-length p53 in response to developmental and DNA-damaging signals. More importantly, we show that Delta113p53 functions to antagonize p53-induced apoptosis via activating bcl2L (closest to human Bcl-x(L)), and knockdown of Delta113p53 enhances p53-mediated apoptosis under stress conditions. Thus, we demonstrate that the p53 genetic locus contains a new p53 response gene and that Delta113p53 does not act in a dominant-negative manner toward p53 but differentially modulates p53 target gene expression to antagonize p53 apoptotic activity at the physiological level in zebrafish. Our results establish a novel feedback pathway that modulates the p53 response and suggest that modulation of the p53 pathway by p53 isoforms might have an impact on p53 tumor suppressor activity.
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Affiliation(s)
- Jun Chen
- Functional Genomics Laboratory, Institute of Molecular and Cell Biology, Proteos, Singapore
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96
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Feng CY, Johnson SC, Hori TS, Rise M, Hall JR, Gamperl AK, Hubert S, Kimball J, Bowman S, Rise ML. Identification and analysis of differentially expressed genes in immune tissues of Atlantic cod stimulated with formalin-killed, atypical Aeromonas salmonicida. Physiol Genomics 2009; 37:149-63. [PMID: 19240301 DOI: 10.1152/physiolgenomics.90373.2008] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Physiological changes, elicited in animal immune tissues by exposure to pathogens, may be studied using functional genomics approaches. We created and characterized reciprocal suppression subtractive hybridization (SSH) cDNA libraries to identify differentially expressed genes in spleen and head kidney tissues of Atlantic cod (Gadus morhua) challenged with intraperitoneal injections of formalin-killed, atypical Aeromonas salmonicida. Of 4,154 ESTs from four cDNA libraries, 10 genes with immune-relevant functional annotations were selected for QPCR studies using individual fish templates to assess biological variability. Genes confirmed by QPCR as upregulated by A. salmonicida included interleukin-1 beta, interleukin-8, a small inducible cytokine, interferon regulatory factor 1 (IRF1), ferritin heavy subunit, cathelicidin, and hepcidin. This study is the first large-scale discovery of bacteria-responsive genes in cod and the first to demonstrate upregulation of IRF1 in fish immune tissues as a result of bacterial antigen stimulation. Given the importance of IRF1 in vertebrate immune responses to viral and bacterial pathogens, the full-length cDNA sequence of Atlantic cod IRF1 was obtained and compared with putative orthologous sequences from other organisms. Functional annotations of assembled SSH library ESTs showed that bacterial antigen stimulation caused changes in many biological processes including chemotaxis, regulation of apoptosis, antimicrobial peptide production, and iron homeostasis. Moreover, differences in spleen and head kidney gene expression responses to the bacterial antigens pointed to a potential role for the cod spleen in blood-borne pathogen clearance. Our data show that Atlantic cod immune tissue responses to bacterial antigens are similar to those seen in other fish species and higher vertebrates.
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Affiliation(s)
- Charles Y Feng
- Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, Newfoundland
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97
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Misumi I, Yada T, Leong JAC, Schreck CB. The effect of in vitro exposure to tributyltin on the immune competence of Chinook salmon (Oncorhynchus tshawytscha) leukocytes. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2009; 56:229-237. [PMID: 18629429 DOI: 10.1007/s00244-008-9187-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2008] [Accepted: 05/31/2008] [Indexed: 05/26/2023]
Abstract
We evaluated the direct effects of in vitro exposures to tributyltin (TBT), a widely used biocide, on the cell-mediated immune system of Chinook salmon (Oncorhynchus tshawytscha). Splenic and pronephric leukocytes isolated from juvenile Chinook salmon were exposed to TBT (0, 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6 mg/l) in cell cultures for 24 h. Effects of TBT on cell viability, induction of apoptosis, and mitogenic responses were measured by flow cytometry. Splenic and pronephric leukocytes in the presence of TBT experienced a concentration-dependent decrease in viability in cell cultures. Apoptosis was detected as one of the mechanisms of cell death after TBT exposure. In addition, pronephric lymphocytes exhibited a greater sensitivity to TBT exposure than pronephric granulocytes. The functional ability of splenic B-cells to undergo blastogenesis upon lipopolysaccharide stimulation was also significantly inhibited in the presence of 0.05, 0.07, or 0.10 mg/l of TBT in the cell cultures. Flow cytometric assay using a fluorescent conjugated monoclonal antibody against salmon surface immunoglobulin was employed for the conclusive identification of B-cells in the Chinook salmon leukocytes. Our findings suggest that adverse effects of TBT on the function or development of fish immune systems could lead to an increase in disease susceptibility and its subsequent ecological implications.
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Affiliation(s)
- Ichiro Misumi
- Department of Microbiology, Oregon State University, Corvallis, OR 97331, USA.
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98
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Krumschnabel G, Podrabsky JE. Fish as model systems for the study of vertebrate apoptosis. Apoptosis 2008; 14:1-21. [PMID: 19082731 DOI: 10.1007/s10495-008-0281-y] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Accepted: 11/17/2008] [Indexed: 01/18/2023]
Abstract
Apoptosis is a process of pivotal importance for multi-cellular organisms and due to its implication in the development of cancer and degenerative disease it is intensively studied in humans and mammalian model systems. Invertebrate models of apoptosis have been well-studied, especially in C. elegans and D. melanogaster, but as these are evolutionarily distant from mammals the relevance of findings for human research is sometimes limited. Presently, a non-mammalian vertebrate model for studying apoptosis is missing. However, in the past few years an increasing number of studies on cell death in fish have been published and thus new model systems may emerge. This review aims at highlighting the most important of these findings, showing similarities and dissimilarities between fish and mammals, and will suggest topics for future research. In addition, the outstanding usefulness of fish as research models will be pointed out, hoping to spark future research on this exciting, often underrated group of vertebrates.
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Affiliation(s)
- Gerhard Krumschnabel
- Division of Developmental Immunology, Biocenter, Innsbruck Medical University, 6020 Innsbruck, Austria.
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99
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Nguyen N, Zhu Y. Prolactin functions as a survival factor during zebrafish embryogenesis. Comp Biochem Physiol A Mol Integr Physiol 2008; 153:88-93. [PMID: 19032987 DOI: 10.1016/j.cbpa.2008.10.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2008] [Revised: 10/20/2008] [Accepted: 10/22/2008] [Indexed: 10/21/2022]
Abstract
Prolactin is a multifaceted hormone that is capable of modulating hundreds of physiological processes in adult vertebrates. However, the physiological functions of prolactin in embryonic development are still controversial. One of these biological functions of prolactin is to promote survival of the cells. Almost all studies on the anti-apoptotic action of prolactin have been focused on a variety of mammalian cell lines and tissues, while no study has been reported on prolactin's anti-apoptotic role in the embryo. In order to determine whether prolactin acts as a survival factor for embryonic cells during development, prolactin protein was knocked-down in zebrafish embryos by microinjection of prolactin-morpholino antisense (PRL-MO). Significant increase in the number of apoptotic cells was observed in embryos treated with PRL-MO compared to control embryos injected with control morpholino or non-injected controls. The number of apoptotic cells increased more significantly between 15 and 35 h post-fertilization in the PRL-MO treated group than that of the control. Interestingly, apoptotic cells were restricted to the central nervous system, particularly in the eyes and brain. Apoptosis of these cells was further demonstrated using the comet assay to detect DNA damage, a hallmark of apoptosis. It was found that the level of DNA damage was dose-dependent on the concentration of PRL-MO injected and consistent with higher levels of nick ends detected by the TUNEL assay in PRL-MO embryos. Further examination of apoptotic genes indicated the transcript of caspase-8, a representative caspase gene of the extrinsic pathway, was much higher in prolactin knockdown embryos than the non-injected control. Together, these results suggest that prolactin acts as a survival factor during zebrafish embryogenesis.
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Affiliation(s)
- Nhu Nguyen
- Department of Biology, East Carolina University, Greenville, NC 27858, USA
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100
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Langenau DM, Keefe MD, Storer NY, Jette CA, Smith ACH, Ceol CJ, Bourque C, Look AT, Zon LI. Co-injection strategies to modify radiation sensitivity and tumor initiation in transgenic Zebrafish. Oncogene 2008; 27:4242-8. [PMID: 18345029 PMCID: PMC2680704 DOI: 10.1038/onc.2008.56] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2007] [Revised: 01/16/2008] [Accepted: 02/01/2008] [Indexed: 12/19/2022]
Abstract
The zebrafish has emerged as a powerful genetic model of cancer, but has been limited by the use of stable transgenic approaches to induce disease. Here, a co-injection strategy is described that capitalizes on both the numbers of embryos that can be microinjected and the ability of transgenes to segregate together and exert synergistic effects in forming tumors. Using this mosaic transgenic approach, gene pathways involved in tumor initiation and radiation sensitivity have been identified.
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Affiliation(s)
- D M Langenau
- Stem Cell Program and Division of Hematology/Oncology, Children's Hospital Boston and Dana-Farber Cancer Institute, Boston, MA 2115, USA.
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