The Experts below are selected from a list of 11196 Experts worldwide ranked by ideXlab platform
Stefan Hoppler - One of the best experts on this subject based on the ideXlab platform.
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wnt β catenin signalling regulates cardiomyogenesis via GATA Transcription Factors
Journal of Anatomy, 2010Co-Authors: Jennifer C. Martin, Boni A. Afouda, Stefan HopplerAbstract:A functioning heart muscle is required continuously throughout life. During embryonic development the heart muscle tissue differentiates from mesoderm that has heart-forming potential. Heart-forming potential in the embryonic mesoderm is regulated by pro-cardiogenic Transcription Factors, such as members of the GATA and NK-2 Transcription factor families. Subsequent heart muscle differentiation involves the expression of cytoskeletal proteins, including myosins and troponins. Different Wnt signalling pathways have various functions in heart development. So-called ‘canonical’ (Wnt/β-catenin-mediated) signalling has a conserved role in vertebrate heart development, regulating and restricting heart development and subsequent heart muscle differentiation. Here we investigated the way in which Wnt/β-catenin signalling functionally interacts with the GATA family of pro-cardiogenic Transcription Factors to regulate subsequent heart muscle differentiation. We used whole Xenopus embryos as an accessible experimental model system for vertebrate heart development. Our experiments confirmed that activation of Wnt signalling results in reduced GATA gene expression, as well as reduced gene expression of other pro-cardiogenic Transcription Factors and heart muscle differentiation markers. Remarkably, we discovered that when GATA function is experimentally restored, the expression of other pro-cardiogenic Transcription Factors and heart muscle differentiation markers is rescued. These findings, obtained from whole-embryo experiments, show that Wnt signalling regulates heart development at the level of GATA Factors, confirming earlier results from tissue-culture experiments. Furthermore, our rescue experiments in Xenopus embryos revealed differences in functional activity between the various GATA Transcription Factors involved in heart development. We discovered that GATA4 is more efficient at reinstating the gene expression of other pro-cardiogenic Transcription Factors, whereas GATA6 is more potent at promoting the expression of genes associated with terminal heart muscle differentiation. In conclusion, our findings show that the inhibition of heart development by Wnt/β-catenin signalling during organogenesis is mediated by the loss of expression of GATA pro-cardiogenic Transcription Factors and reveal functional differences between those GATA Factors in heart development.
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Wnt/β-catenin signalling regulates cardiomyogenesis via GATA Transcription Factors
Journal of anatomy, 2010Co-Authors: Jennifer C. Martin, Boni A. Afouda, Stefan HopplerAbstract:A functioning heart muscle is required continuously throughout life. During embryonic development the heart muscle tissue differentiates from mesoderm that has heart-forming potential. Heart-forming potential in the embryonic mesoderm is regulated by pro-cardiogenic Transcription Factors, such as members of the GATA and NK-2 Transcription factor families. Subsequent heart muscle differentiation involves the expression of cytoskeletal proteins, including myosins and troponins. Different Wnt signalling pathways have various functions in heart development. So-called ‘canonical’ (Wnt/β-catenin-mediated) signalling has a conserved role in vertebrate heart development, regulating and restricting heart development and subsequent heart muscle differentiation. Here we investigated the way in which Wnt/β-catenin signalling functionally interacts with the GATA family of pro-cardiogenic Transcription Factors to regulate subsequent heart muscle differentiation. We used whole Xenopus embryos as an accessible experimental model system for vertebrate heart development. Our experiments confirmed that activation of Wnt signalling results in reduced GATA gene expression, as well as reduced gene expression of other pro-cardiogenic Transcription Factors and heart muscle differentiation markers. Remarkably, we discovered that when GATA function is experimentally restored, the expression of other pro-cardiogenic Transcription Factors and heart muscle differentiation markers is rescued. These findings, obtained from whole-embryo experiments, show that Wnt signalling regulates heart development at the level of GATA Factors, confirming earlier results from tissue-culture experiments. Furthermore, our rescue experiments in Xenopus embryos revealed differences in functional activity between the various GATA Transcription Factors involved in heart development. We discovered that GATA4 is more efficient at reinstating the gene expression of other pro-cardiogenic Transcription Factors, whereas GATA6 is more potent at promoting the expression of genes associated with terminal heart muscle differentiation. In conclusion, our findings show that the inhibition of heart development by Wnt/β-catenin signalling during organogenesis is mediated by the loss of expression of GATA pro-cardiogenic Transcription Factors and reveal functional differences between those GATA Factors in heart development.
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GATA Transcription Factors integrate wnt signalling during heart development
Journal of Cell Science, 2008Co-Authors: Boni Anatole Afouda, Jennifer L. Martin, Fei Liu, Roger Patient, Aldo Ciauuitz, Stefan HopplerAbstract:1. Afouda et al. 2008. Development doi:10.1242/dev.026443 [OpenUrl][1][Abstract/FREE Full Text][2] [1]: {openurl}?query=rft.jtitle%253DDevelopment%26rft_id%253Dinfo%253Adoi%252F10.1242%252Fdev.026443%26rft_id%253Dinfo%253Apmid%252F18715946%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%
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GATA Transcription Factors integrate Wnt signalling during heart development.
Development (Cambridge England), 2008Co-Authors: Boni Anatole Afouda, Jennifer L. Martin, Fei Liu, Aldo Ciau-uitz, Roger Patient, Stefan HopplerAbstract:Cardiogenesis is inhibited by canonical Wnt/β-catenin signalling and stimulated by non-canonical Wnt11/JNK signalling, but how these two signalling pathways crosstalk is currently unknown. Here, we show that Wnt/β-catenin signalling restricts cardiogenesis via inhibition of GATA gene expression, as experimentally reinstating GATA function overrides β-catenin-mediated inhibition and restores cardiogenesis. Furthermore, we show that GATA Transcription Factors in turn directly regulate Wnt11 gene expression, and that Wnt11 is required to a significant degree for mediating the cardiogenesis-promoting function of GATA Transcription Factors. These results demonstrate that GATA Factors occupy a central position between canonical and non-canonical Wnt signalling in regulating heart muscle formation.
Claus Schwechheimer - One of the best experts on this subject based on the ideXlab platform.
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LLM-domain B-GATA Transcription Factors Play Multifaceted Roles in Controlling Greening in Arabidopsis
The Plant cell, 2018Co-Authors: Emmanouil Bastakis, Boris Hedtke, Carina Klermund, Bernhard Grimm, Claus SchwechheimerAbstract:Chlorophyll accumulation and chloroplast development are regulated at multiple levels during plant development. The paralogous LLM-domain B-GATA Transcription Factors GNC and GNL contribute to chlorophyll biosynthesis and chloroplast formation in light-grown Arabidopsis thaliana seedlings. Whereas there is already ample knowledge about the Transcriptional regulation of GNC and GNL, the identity of their downstream targets is largely unclear. Here, we identified genes controlling greening directly downstream of the GATAs by integrating data from RNA-sequencing and microarray data sets. We found that genes encoding subunits of the Mg-chelatase complex and 3,8-divinyl protochlorophyllide a 8-vinyl reductase (DVR) likely function directly downstream of the GATAs and that DVR expression is limiting in the pale-green gnc gnl mutants. The GATAs also regulate the nucleus-encoded SIGMA (SIG) factor genes, which control Transcription in the chloroplast and suppress the greening defects of sig mutants. Furthermore, GNC and GNL act, at the gene expression level, in an additive manner with the GOLDEN2-LIKE1 (GLK1) and GLK2 Transcription factor genes, which are also important for proper chlorophyll accumulation. We thus reveal that chlorophyll biosynthesis genes are directly controlled by LLM-domain B-GATAs and demonstrate that these Transcription Factors play an indirect role in the control of greening through regulating SIGMA factor genes.
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llm domain b GATA Transcription Factors promote stomatal development downstream of light signaling pathways in arabidopsis thaliana hypocotyls
The Plant Cell, 2016Co-Authors: Carina Klermund, Emmanouil Bastakis, Quirin L. Ranftl, René Richter, Julia Diener, Claus SchwechheimerAbstract:Stomata are pores that regulate the gas and water exchange between the environment and aboveground plant tissues, including hypocotyls, leaves, and stems. Here, we show that mutants of Arabidopsis thaliana LLM-domain B-GATA genes are defective in stomata formation in hypocotyls. Conversely, stomata formation is strongly promoted by overexpression of various LLM-domain B-class GATA genes, most strikingly in hypocotyls but also in cotyledons. Genetic analyses indicate that these B-GATAs act upstream of the stomata formation regulators SPEECHLESS (SPCH), MUTE, and SCREAM/SCREAM2 and downstream or independent of the patterning regulators TOO MANY MOUTHS and STOMATAL DENSITY AND DISTRIBUTION1. The effects of the GATAs on stomata formation are light dependent but can be induced in dark-grown seedlings by red, far-red, or blue light treatments. PHYTOCHROME INTERACTING FACTOR (PIF) mutants form stomata in the dark, and in this genetic background, GATA expression is sufficient to induce stomata formation in the dark. Since the expression of the LLM-domain B-GATAs GNC (GATA, NITRATE-INDUCIBLE, CARBON METABOLISM-INVOLVED) and GNC-LIKE/CYTOKININ-RESPONSIVE GATA FACTOR1 as well as that of SPCH is red light induced but the induction of SPCH is compromised in a GATA gene mutant background, we hypothesize that PIF- and light-regulated stomata formation in hypocotyls is critically dependent on LLM-domain B-GATA genes.
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B-GATA Transcription Factors – insights into their structure, regulation, and role in plant development
Frontiers in plant science, 2015Co-Authors: Carina Behringer, Claus SchwechheimerAbstract:GATA Transcription Factors are evolutionarily conserved Transcriptional regulators that recognize promoter elements with a G-A-T-A core sequence. In comparison to animal genomes, the GATA Transcription factor family in plants is comparatively large with approximately 30 members. In spite of a long-standing interest of plant molecular biologists in GATA Factors, only research conducted in the last years has led to reliable insights into their functions during plant development. Here, we review the current knowledge on B-GATAs, one of four GATA factor subfamilies from Arabidopsis thaliana. We show that B-GATAs can be subdivided based on structural features and their biological function into family members with a C-terminal LLM- (leucine-leucine-methionine) domain or an N-terminal HAN- (HANABA TARANU) domain. The paralogous GNC (GATA, NITRATE-INDUCIBLE, CARBON-METABOLISM INVOLVED) and CGA1/GNL (CYTOKININ-INDUCED GATA1/GNC-LIKE) are introduced as LLM-domain containing B-GATAs from Arabidopsis that control germination, greening, senescence and flowering time downstream from several growth regulatory signals including light and the hormones gibberellin, auxin, and cytokinin. Arabidopsis HAN and its monocot-specific paralogs from rice (NECK LEAF1), maize (TASSEL SHEATH1), and barley (THIRD OUTER GLUME) are HAN-domain-containing B-GATAs with a predominant role in embryo development and floral development. We also review GATA23, a regulator of lateral root initiation from Arabidopsis, that is closely related to GNC and GNL but has a degenerate LLM-domain that is seemingly specific for the Brassicaceae family. The Brassicaceae-specific GATA23 together with the above-mentioned monocot-specific HAN-domain GATAs provide evidence that neofunctionalization of the B-GATAs was used during plant evolution to expand the functional repertoire of these Transcription Factors.
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b GATA Transcription Factors insights into their structure regulation and role in plant development
Frontiers in Plant Science, 2015Co-Authors: Carina Behringer, Claus SchwechheimerAbstract:GATA Transcription Factors are evolutionarily conserved Transcriptional regulators that recognize promoter elements with a G-A-T-A core sequence. In comparison to animal genomes, the GATA Transcription factor family in plants is comparatively large with approximately 30 members. In spite of a long-standing interest of plant molecular biologists in GATA Factors, only research conducted in the last years has led to reliable insights into their functions during plant development. Here, we review the current knowledge on B-GATAs, one of four GATA factor subfamilies from Arabidopsis thaliana. We show that B-GATAs can be subdivided based on structural features and their biological function into family members with a C-terminal LLM- (leucine-leucine-methionine) domain or an N-terminal HAN- (HANABA TARANU) domain. The paralogous GNC (GATA, NITRATE-INDUCIBLE, CARBON-METABOLISM INVOLVED) and CGA1/GNL (CYTOKININ-INDUCED GATA1/GNC-LIKE) are introduced as LLM-domain containing B-GATAs from Arabidopsis that control germination, greening, senescence and flowering time downstream from several growth regulatory signals including light and the hormones gibberellin, auxin, and cytokinin. Arabidopsis HAN and its monocot-specific paralogs from rice (NECK LEAF1), maize (TASSEL SHEATH1), and barley (THIRD OUTER GLUME) are HAN-domain-containing B-GATAs with a predominant role in embryo development and floral development. We also review GATA23, a regulator of lateral root initiation from Arabidopsis, that is closely related to GNC and GNL but has a degenerate LLM-domain that is seemingly specific for the Brassicaceae family. The Brassicaceae-specific GATA23 together with the above-mentioned monocot-specific HAN-domain GATAs provide evidence that neofunctionalization of the B-GATAs was used during plant evolution to expand the functional repertoire of these Transcription Factors.
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Functional diversification within the family of B-GATA Transcription Factors through the leucine-leucine-methionine domain.
Plant physiology, 2014Co-Authors: Carina Behringer, Emmanouil Bastakis, Quirin L. Ranftl, Klaus F. X. Mayer, Claus SchwechheimerAbstract:The Transcription of the Arabidopsis (Arabidopsis thaliana) GATA Transcription Factors GATA, NITRATE-INDUCIBLE, CARBON METABOLISM-INVOLVED (GNC) and GNC-LIKE (GNL)/CYTOKININ-RESPONSIVE GATA FACTOR1 is controlled by several growth regulatory signals including light and the phytohormones auxin, cytokinin, and gibberellin. To date, GNC and GNL have been attributed functions in the control of germination, greening, flowering time, floral development, senescence, and floral organ abscission. GNC and GNL belong to the 11-member family of B-class GATA Transcription Factors that are characterized to date solely by their high sequence conservation within the GATA DNA-binding domain. The degree of functional conservation among the various B-class GATA family members is not understood. Here, we identify and examine B-class GATAs from Arabidopsis, tomato (Solanum lycopersicon), Brachypodium (Brachypodium distachyon), and barley (Hordeum vulgare). We find that B-class GATAs from these four species can be subdivided based on their short or long N termini and the presence of the 13-amino acid C-terminal leucine-leucine-methionine (LLM) domain with the conserved motif LLM. Through overexpression analyses and by complementation of a gnc gnl double mutant, we provide evidence that the length of the N terminus may not allow distinguishing between the different B-class GATAs at the functional level. In turn, we find that the presence and absence of the LLM domain in the overexpressors has differential effects on hypocotyl elongation, leaf shape, and petiole length, as well as on gene expression. Thus, our analyses identify the LLM domain as an evolutionarily conserved domain that determines B-class GATA factor identity and provides a further subclassification criterion for this Transcription factor family.
Boni Anatole Afouda - One of the best experts on this subject based on the ideXlab platform.
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GATA Transcription Factors integrate wnt signalling during heart development
Journal of Cell Science, 2008Co-Authors: Boni Anatole Afouda, Jennifer L. Martin, Fei Liu, Roger Patient, Aldo Ciauuitz, Stefan HopplerAbstract:1. Afouda et al. 2008. Development doi:10.1242/dev.026443 [OpenUrl][1][Abstract/FREE Full Text][2] [1]: {openurl}?query=rft.jtitle%253DDevelopment%26rft_id%253Dinfo%253Adoi%252F10.1242%252Fdev.026443%26rft_id%253Dinfo%253Apmid%252F18715946%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%
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GATA Transcription Factors integrate Wnt signalling during heart development.
Development (Cambridge England), 2008Co-Authors: Boni Anatole Afouda, Jennifer L. Martin, Fei Liu, Aldo Ciau-uitz, Roger Patient, Stefan HopplerAbstract:Cardiogenesis is inhibited by canonical Wnt/β-catenin signalling and stimulated by non-canonical Wnt11/JNK signalling, but how these two signalling pathways crosstalk is currently unknown. Here, we show that Wnt/β-catenin signalling restricts cardiogenesis via inhibition of GATA gene expression, as experimentally reinstating GATA function overrides β-catenin-mediated inhibition and restores cardiogenesis. Furthermore, we show that GATA Transcription Factors in turn directly regulate Wnt11 gene expression, and that Wnt11 is required to a significant degree for mediating the cardiogenesis-promoting function of GATA Transcription Factors. These results demonstrate that GATA Factors occupy a central position between canonical and non-canonical Wnt signalling in regulating heart muscle formation.
Feng Yue - One of the best experts on this subject based on the ideXlab platform.
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systematic integration of GATA Transcription Factors and epigenomes via ideas paints the regulatory landscape of hematopoietic cells
Iubmb Life, 2020Co-Authors: Ross C Hardison, Yu Zhang, Cheryl A Keller, Guanjue Xiang, Elisabeth F Heuston, Jens Lichtenberg, Belinda Giardine, David M Bodine, Shaun Mahony, Feng YueAbstract:Members of the GATA family of Transcription Factors play key roles in the differentiation of specific cell lineages by regulating the expression of target genes. Three GATA Factors play distinct roles in hematopoietic differentiation. In order to better understand how these GATA Factors function to regulate genes throughout the genome, we are studying the epigenomic and Transcriptional landscapes of hematopoietic cells in a model-driven, integrative fashion. We have formed the collaborative multi-lab VISION project to conduct ValIdated Systematic IntegratiON of epigenomic data in mouse and human hematopoiesis. The epigenomic data included nuclease accessibility in chromatin, CTCF occupancy, and histone H3 modifications for 20 cell types covering hematopoietic stem cells, multilineage progenitor cells, and mature cells across the blood cell lineages of mouse. The analysis used the Integrative and Discriminative Epigenome Annotation System (IDEAS), which learns all common combinations of features (epigenetic states) simultaneously in two dimensions-along chromosomes and across cell types. The result is a segmentation that effectively paints the regulatory landscape in readily interpretable views, revealing constitutively active or silent loci as well as the loci specifically induced or repressed in each stage and lineage. Nuclease accessible DNA segments in active chromatin states were designated candidate cis-regulatory elements in each cell type, providing one of the most comprehensive registries of candidate hematopoietic regulatory elements to date. Applications of VISION resources are illustrated for the regulation of genes encoding GATA1, GATA2, GATA3, and Ikaros. VISION resources are freely available from our website http://usevision.org.
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systematic integration of GATA Transcription Factors and epigenomes via ideas paints the regulatory landscape of mouse hematopoietic cells
bioRxiv, 2019Co-Authors: Ross C Hardison, Yu Zhang, Cheryl A Keller, Guanjue Xiang, Elisabeth F Heuston, Jens Lichtenberg, Belinda Giardine, David M Bodine, Shaun Mahony, Feng YueAbstract:Summary Members of the GATA family of Transcription Factors play key roles in the differentiation of specific cell lineages by regulating the expression of target genes. Three GATA Factors play distinct roles in hematopoietic differentiation. In order to better understand how these GATA Factors function to regulate genes throughout the genome, we are studying the epigenomic and Transcriptional landscapes of hematopoietic cells in a model-driven, integrative fashion. We have formed the collaborative multi-lab VISION project to conduct ValIdated Systematic IntegratiON of epigenomic data in mouse and human hematopoiesis. The epigenomic data included nuclease accessibility in chromatin, CTCF occupancy, and histone H3 modifications for twenty cell types covering hematopoietic stem cells, multilineage progenitor cells, and mature cells across the blood cell lineages of mouse. The analysis used the Integrative and Discriminative Epigenome Annotation System (IDEAS), which learns all common combinations of features (epigenetic states) simultaneously in two dimensions - along chromosomes and across cell types. The result is a segmentation that effectively paints the regulatory landscape in readily interpretable views, revealing constitutively active or silent loci as well as the loci specifically induced or repressed in each stage and lineage. Nuclease accessible DNA segments in active chromatin states were designated candidate cis-regulatory elements in each cell type, providing one of the most comprehensive registries of candidate hematopoietic regulatory elements to date. Applications of VISION resources are illustrated for regulation of genes encoding GATA1, GATA2, GATA3, and Ikaros. VISION resources are freely available from our website http://usevision.org.
Eric N Olson - One of the best experts on this subject based on the ideXlab platform.
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target gene specific modulation of myocardin activity by GATA Transcription Factors
Molecular and Cellular Biology, 2004Co-Authors: Jiyeon Oh, Chingling Lien, Weibing Xing, Dazhi Wang, Zhigao Wang, Eric N OlsonAbstract:Myocardin is a Transcriptional coactivator that regulates cardiac and smooth muscle gene expression by associating with serum response factor. We show that GATA Transcription Factors can either stimulate or suppress the Transcriptional activity of myocardin, depending on the target gene. Modulation of myocardin activity by GATA4 is mediated by the physical interaction of myocardin with the DNA binding domain of GATA4 but does not require binding of GATA4 to DNA. Paradoxically, the Transcription activation domain of GATA4 is dispensable for the stimulatory effect of GATA4 on myocardin activity but is required for repression of myocardin activity. The ability of GATA Transcription Factors to modulate myocardin activity provides a potential mechanism for fine tuning the expression of serum response factor target genes in a gene-specific manner.
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Direct Activation of a GATA6 Cardiac Enhancer by Nkx2.5: Evidence for a Reinforcing Regulatory Network of Nkx2.5 and GATA Transcription Factors in the Developing Heart
Developmental biology, 2000Co-Authors: Jeffery D. Molkentin, Christopher L. Antos, Brian Mercer, Tyler Taigen, Joseph M. Miano, Eric N OlsonAbstract:Abstract The zinc finger Transcription Factors GATA4, -5, and -6 and the homeodomain protein Nkx2.5 are expressed in the developing heart and have been shown to activate a variety of cardiac-specific genes. To begin to define the regulatory relationships between these cardiac Transcription Factors and to understand the mechanisms that control their expression during cardiogenesis, we analyzed the mouse GATA6 gene for regulatory elements sufficient to direct cardiac expression during embryogenesis. Using β-galactosidase fusion constructs in transgenic mice, a 4.3-kb 5′ regulatory region that directed Transcription specifically in the cardiac lineage, beginning at the cardiac crescent stage, was identified. Thereafter, transgene expression became compartmentalized to the outflow tract, a portion of the right ventricle, and a limited region of the common atrial chamber of the embryonic heart. Further dissection of this regulatory region identified a 1.8-kb cardiac-specific enhancer that recapitulated the expression pattern of the larger region when fused to a heterologous promoter and a smaller 500-bp subregion that retained cardiac expression, but was quantitatively weaker. The GATA6 cardiac enhancer contained a binding site for Nkx2.5 that was essential for cardiac-specific expression in transgenic mice. These studies demonstrate that GATA6 is a direct target gene for Nkx2.5 in the developing heart and reveal a mutually reinforcing regulatory network of Nkx2.5 and GATA Transcription Factors during cardiogenesis.
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FOG-2, a Heart- and Brain-Enriched Cofactor for GATA Transcription Factors
Molecular and cellular biology, 1999Co-Authors: Timothy A. Mckinsey, Dazhi Wang, James A. Richardson, Eric N OlsonAbstract:Members of the GATA family of zinc finger Transcription Factors have been shown to play important roles in the control of gene expression in a variety of cell types. GATA-1, -2, and -3 are expressed primarily in hematopoietic cell lineages and are required for proliferation and differentiation of multiple hematopoietic cell types, whereas GATA-4, -5, and -6 are expressed in the heart, where they activate cardiac muscle structural genes. Friend of GATA-1 (FOG) is a multitype zinc finger protein that interacts with GATA-1 and serves as a cofactor for GATA-1-mediated Transcription. FOG is coexpressed with GATA-1 in developing erythroid and megakaryocyte cell lineages and cooperates with GATA-1 to control erythropoiesis. We describe a novel FOG-related factor, FOG-2, that is expressed predominantly in the developing and adult heart, brain, and testis. FOG-2 interacts with GATA Factors, and interaction of GATA-4 and FOG-2 results in either synergistic activation or repression of GATA-dependent cardiac promoters, depending on the specific promoter and the cell type in which they are tested. The properties of FOG-2 suggest its involvement in the control of cardiac and neural gene expression by GATA Transcription Factors.