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Masayuki Yamamoto - One of the best experts on this subject based on the ideXlab platform.
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GATA2 and pu 1 collaborate to activate the expression of the mouse ms4a2 gene encoding fceriβ through distinct mechanisms
Molecular and Cellular Biology, 2019Co-Authors: Shin'ya Ohmori, Yasushi Ishijima, Masayuki Yamamoto, Suzuka Numata, Mai Takahashi, Masataka Sekita, Taichi Sato, Keisuke Chugun, Kinuko OhnedaAbstract:GATA factors GATA1 and GATA2 and ETS factor PU.1 are known to function antagonistically during hematopoietic development. In mouse mast cells, however, these factors are coexpressed and activate the expression of the Ms4a2 gene encoding the β chain of the high-affinity IgE receptor (FceRI). The present study showed that these factors cooperatively regulate Ms4a2 gene expression through distinct mechanisms. Although GATA2 and PU.1 contributed almost equally to Ms4a2 gene expression, gene ablation experiments revealed that simultaneous knockdown of both factors showed neither a synergistic nor an additive effect. A chromatin immunoprecipitation analysis showed that they shared DNA binding to the +10.4-kbp region downstream of the Ms4a2 gene with chromatin looping factor LDB1, whereas the proximal -60-bp region was exclusively bound by GATA2 in a mast cell-specific manner. Ablation of PU.1 significantly reduced the level of GATA2 binding to both the +10.4-kbp and -60-bp regions. Surprisingly, the deletion of the +10.4-kbp region by genome editing completely abolished the Ms4a2 gene expression as well as the cell surface expression of FceRI. These results suggest that PU.1 and LDB1 play central roles in the formation of active chromatin structure whereas GATA2 directly activates the Ms4a2 promoter.
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mouse tryptase gene expression is coordinately regulated by gata1 and GATA2 in bone marrow derived mast cells
International Journal of Molecular Sciences, 2019Co-Authors: Kinuko Ohneda, Shin'ya Ohmori, Masayuki YamamotoAbstract:Mast cell tryptases have crucial roles in allergic and inflammatory diseases. The mouse tryptase genes represent a cluster of loci on chromosome 16p3.3. While their functional studies have been extensively performed, transcriptional regulation of tryptase genes is poorly understood. In this study, we examined the molecular basis of the tryptase gene expression in bone marrow-derived mast cells (BMMCs) of C57BL/6 mice and in MEDMC-BRC6 mast cells. The expression of the Tpsb2 and Tpsg1 genes, which reside at the 3′-end of the tryptase locus, is significantly decreased by the reduction of the GATA transcription factors GATA1 or GATA2. Chromatin immunoprecipitation assays have shown that the GATA factors bind at multiple regions within the locus, including 1.0 and 72.8 kb upstream of the Tpsb2 gene, and that GATA1 and GATA2 facilitate each other’s DNA binding activity to these regions. Deletion of the −72.8 kb region by genome editing significantly reduced the Tpsb2 and Tpsg1 mRNA levels in MEDMC-BRC6 cells. Furthermore, binding of CTCF and the cohesin subunit Rad21 was found upstream of the −72.8 kb region and was significantly reduced in the absence of GATA1. These results suggest that mouse tryptase gene expression is coordinately regulated by GATA1 and GATA2 in BMMCs.
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spiral ganglion cell degeneration induced deafness as a consequence of reduced gata factor activity
Genes to Cells, 2019Co-Authors: Masayuki Yamamoto, Jun Takai, Tomofumi Hoshino, Tsumoru Terunuma, Satoshi Uemura, Yasuhiro Nakamura, Michito Hamada, Satoru Takahashi, James Douglas EngelAbstract:Zinc-finger transcription factors GATA2 and GATA3 are both expressed in the developing inner ear, although their overlapping versus distinct activities in adult definitive inner ear are not well understood. We show here that GATA2 and GATA3 are co-expressed in cochlear spiral ganglion cells and redundantly function in the maintenance of spiral ganglion cells and auditory neural circuitry. Notably, GATA2 and Gata3 compound heterozygous mutant mice had a diminished number of spiral ganglion cells due to enhanced apoptosis, which resulted in progressive hearing loss. The decrease in spiral ganglion cellularity was associated with lowered expression of neurotrophin receptor TrkC that is an essential factor for spiral ganglion cell survival. We further show that GATA2 null mutants that additionally bear a GATA2 YAC (yeast artificial chromosome) that counteracts the lethal hematopoietic deficiency due to complete GATA2 loss nonetheless failed to complement the deficiency in neonatal spiral ganglion neurons. Furthermore, cochlea-specific GATA2 deletion mice also had fewer spiral ganglion cells and resultant hearing impairment. These results show that GATA2 and GATA3 redundantly function to maintain spiral ganglion cells and hearing. We propose possible mechanisms underlying hearing loss in human GATA2- or GATA3-related genetic disorders.
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reducing inflammatory cytokine production from renal collecting duct cells by inhibiting GATA2 ameliorates acute kidney injury
Molecular and Cellular Biology, 2017Co-Authors: Takashi Moriguchi, Masayuki Yamamoto, Hiroshi Kaneko, Masahiro Nezu, Atsushi Hasegawa, Makiko Hayashi, Hideyuki Saya, Ritsuko ShimizuAbstract:Acute kidney injury (AKI) is a leading cause of chronic kidney disease. Proximal tubules are considered to be the primary origin of pathogenic inflammatory cytokines in AKI. However, it remains unclear whether other cell types, including collecting duct (CD) cells, participate in inflammatory processes. The transcription factor GATA2 is specifically expressed in CD cells and maintains their cellular identity. To explore the pathophysiological function of GATA2 in AKI, we generated renal tubular cell-specific GATA2 deletion (G2CKO) mice and examined their susceptibility to ischemia reperfusion injury (IRI). Notably, G2CKO mice exhibited less severe kidney damage, with reduced granulomacrophagic infiltration upon IRI. Transcriptome analysis revealed that a series of inflammatory cytokine genes were downregulated in GATA2-deficient CD cells, suggesting that GATA2 induces inflammatory cytokine expression in diseased kidney CD cells. Through high-throughput chemical library screening, we identified a potent GATA inhibitor. The chemical reduces cytokine production in CD cells and protects the mouse kidney from IRI. These results revealed a novel pathological mechanism of renal IRI, namely, that CD cells produce inflammatory cytokines and promote IRI progression. In injured kidney CD cells, GATA2 exerts a proinflammatory function by upregulating inflammatory cytokine gene expression. GATA2 can therefore be considered a therapeutic target for AKI.
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Derepression of the DNA Methylation Machinery of the Gata1 Gene Triggers the Differentiation Cue for Erythropoiesis
Molecular and cellular biology, 2017Co-Authors: Jun Takai, James Douglas Engel, Takashi Moriguchi, Mikiko Suzuki, Akihito Otsuki, Fumiki Katsuoka, Saori Katayama, Masahiro Nezu, Masayuki YamamotoAbstract:GATA1 is a critical regulator of erythropoiesis. While the mechanisms underlying the high-level expression of GATA1 in maturing erythroid cells have been studied extensively, the initial activation of the Gata1 gene in early hematopoietic progenitors remains to be elucidated. We previously identified a hematopoietic stem and progenitor cell (HSPC)-specific silencer element (the Gata1 methylation-determining region [G1MDR]) that recruits DNA methyltransferase 1 (Dnmt1) and provokes methylation of the Gata1 gene enhancer. In the present study, we hypothesized that removal of the G1MDR-mediated silencing machinery is the molecular basis of the initial activation of the Gata1 gene and erythropoiesis. To address this hypothesis, we generated transgenic mouse lines harboring a Gata1 bacterial artificial chromosome in which the G1MDR was deleted. The mice exhibited abundant GATA1 expression in HSPCs, in a GATA2-dependent manner. The ectopic GATA1 expression repressed GATA2 transcription and induced erythropoiesis and apoptosis of HSPCs. Furthermore, genetic deletion of Dnmt1 in HSPCs activated Gata1 expression and depleted HSPCs, thus recapitulating the HSC phenotype associated with GATA1 gain of function. These results demonstrate that the G1MDR holds the key to HSPC maintenance and suggest that release from this suppressive mechanism is a fundamental requirement for subsequent initiation of erythroid differentiation.
James Douglas Engel - One of the best experts on this subject based on the ideXlab platform.
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spiral ganglion cell degeneration induced deafness as a consequence of reduced gata factor activity
Genes to Cells, 2019Co-Authors: Masayuki Yamamoto, Jun Takai, Tomofumi Hoshino, Tsumoru Terunuma, Satoshi Uemura, Yasuhiro Nakamura, Michito Hamada, Satoru Takahashi, James Douglas EngelAbstract:Zinc-finger transcription factors GATA2 and GATA3 are both expressed in the developing inner ear, although their overlapping versus distinct activities in adult definitive inner ear are not well understood. We show here that GATA2 and GATA3 are co-expressed in cochlear spiral ganglion cells and redundantly function in the maintenance of spiral ganglion cells and auditory neural circuitry. Notably, GATA2 and Gata3 compound heterozygous mutant mice had a diminished number of spiral ganglion cells due to enhanced apoptosis, which resulted in progressive hearing loss. The decrease in spiral ganglion cellularity was associated with lowered expression of neurotrophin receptor TrkC that is an essential factor for spiral ganglion cell survival. We further show that GATA2 null mutants that additionally bear a GATA2 YAC (yeast artificial chromosome) that counteracts the lethal hematopoietic deficiency due to complete GATA2 loss nonetheless failed to complement the deficiency in neonatal spiral ganglion neurons. Furthermore, cochlea-specific GATA2 deletion mice also had fewer spiral ganglion cells and resultant hearing impairment. These results show that GATA2 and GATA3 redundantly function to maintain spiral ganglion cells and hearing. We propose possible mechanisms underlying hearing loss in human GATA2- or GATA3-related genetic disorders.
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Derepression of the DNA Methylation Machinery of the Gata1 Gene Triggers the Differentiation Cue for Erythropoiesis
Molecular and cellular biology, 2017Co-Authors: Jun Takai, James Douglas Engel, Takashi Moriguchi, Mikiko Suzuki, Akihito Otsuki, Fumiki Katsuoka, Saori Katayama, Masahiro Nezu, Masayuki YamamotoAbstract:GATA1 is a critical regulator of erythropoiesis. While the mechanisms underlying the high-level expression of GATA1 in maturing erythroid cells have been studied extensively, the initial activation of the Gata1 gene in early hematopoietic progenitors remains to be elucidated. We previously identified a hematopoietic stem and progenitor cell (HSPC)-specific silencer element (the Gata1 methylation-determining region [G1MDR]) that recruits DNA methyltransferase 1 (Dnmt1) and provokes methylation of the Gata1 gene enhancer. In the present study, we hypothesized that removal of the G1MDR-mediated silencing machinery is the molecular basis of the initial activation of the Gata1 gene and erythropoiesis. To address this hypothesis, we generated transgenic mouse lines harboring a Gata1 bacterial artificial chromosome in which the G1MDR was deleted. The mice exhibited abundant GATA1 expression in HSPCs, in a GATA2-dependent manner. The ectopic GATA1 expression repressed GATA2 transcription and induced erythropoiesis and apoptosis of HSPCs. Furthermore, genetic deletion of Dnmt1 in HSPCs activated Gata1 expression and depleted HSPCs, thus recapitulating the HSC phenotype associated with GATA1 gain of function. These results demonstrate that the G1MDR holds the key to HSPC maintenance and suggest that release from this suppressive mechanism is a fundamental requirement for subsequent initiation of erythroid differentiation.
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GATA2 Regulates Body Water Homeostasis through Maintaining Aquaporin 2 Expression in Renal Collecting Ducts
Molecular and cellular biology, 2014Co-Authors: Takashi Moriguchi, James Douglas Engel, Jun Takai, Hironori Satoh, Tomokazu Souma, Naoki Morito, Masayuki YamamotoAbstract:The transcription factor GATA2 plays pivotal roles in early renal development, but its distribution and physiological functions in adult kidney are largely unknown. We examined the GATA2 expression pattern in the adult kidney by tracing green fluorescent protein (GFP) fluorescence in GATA2(GFP/+) mice that recapitulate endogenous GATA2 expression and found a robust GFP expression specifically in the renal medulla. Upon purification of the GFP-positive cells, we found that collecting duct (CD)-specific markers, including aquaporin 2 (Aqp2), an important channel for water reabsorption from urine, were abundantly expressed. To address the physiological function of GATA2 in the CD cells, we generated renal tubular cell-specific GATA2-deficient mice (GATA2-CKO) by crossing GATA2 floxed mice with inducible Pax8-Cre mice. We found that the GATA2-CKO mice showed a significant decrease in Aqp2 expression. The GATA2-CKO mice exhibited high 24-h urine volume and low urine osmolality, two important signs of diabetes insipidus. We introduced biotin-tagged GATA2 into a mouse CD-derived cell line and conducted chromatin pulldown assays, which revealed direct GATA2 binding to conserved GATA motifs in the Aqp2 promoter region. A luciferase reporter assay using an Aqp2 promoter-reporter showed that GATA2 trans activates Aqp2 through the GATA motifs. These results demonstrate that GATA2 regulates the Aqp2 gene expression in CD cells and contributes to the maintenance of the body water homeostasis.
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Conditional GATA2 inactivation results in HSC loss and lymphatic mispatterning
The Journal of clinical investigation, 2012Co-Authors: Kim Chew Lim, Masayuki Yamamoto, Sally A. Camper, Tomonori Hosoya, William D. Brandt, Sakie Hosoya-ohmura, James Douglas EngelAbstract:The transcription factor GATA-2 plays vital roles in quite diverse developmental programs, including hematopoietic stem cell (HSC) survival and proliferation. We previously identified a vascular endothelial (VE) enhancer that regulates GATA-2 activity in pan-endothelial cells. To more thoroughly define the in vivo regulatory properties of this enhancer, we generated a tamoxifen-inducible Cre transgenic mouse line using the GATA2 VE enhancer (GATA2 VECre) and utilized it to temporally direct tissue-specific conditional loss of GATA2. Here, we report that GATA2 VECre–mediated loss of GATA-2 led to anemia, hemorrhage, and eventual death in edematous embryos. We further determined that the etiology of anemia in conditional GATA2 mutant embryos involved HSC loss in the fetal liver, as demonstrated by in vitro colony-forming and immunophenotypic as well as in vivo long-term competitive repopulation experiments. We further documented that the edema and hemorrhage in conditional GATA2 mutant embryos were due to defective lymphatic development. Thus, we unexpectedly discovered that in addition to its contribution to endothelial cell development, the VE enhancer also regulates GATA-2 expression in definitive fetal liver and adult BM HSCs, and that GATA-2 function is required for proper lymphatic vascular development during embryogenesis.
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ug4 enhancer driven gata 2 and bone morphogenetic protein 4 complementation remedies the cakut phenotype in GATA2 hypomorphic mutant mice
Molecular and Cellular Biology, 2012Co-Authors: Keiko Ainoya, Shin'ya Ohmori, Takashi Moriguchi, Jun Takai, Ritsuko Shimizu, Tomokazu Souma, Masanobu Morita, Kelly J Chandler, Douglas P Mortlock, James Douglas EngelAbstract:During renal development, the proper emergence of the ureteric bud (UB) from the Wolffian duct is essential for formation of the urinary system. Previously, we showed that expression of transcription factor GATA-2 in the urogenital primordium was demarcated anteroposteriorly into two domains that were regulated by separate enhancers. While GATA-2 expression in the caudal urogenital mesenchyme is controlled by the UG4 enhancer, its more-rostral expression is regulated by UG2. We found that anteriorly displaced budding led to obstructed megaureters in GATA2 hypomorphic mutant mice, possibly due to reduced expression of the downstream effector bone morphogenetic protein 4 (BMP4). Here, we report that UG4-driven, but not UG2-driven, GATA-2 expression in the urogenital mesenchyme significantly reverts the uropathy observed in the GATA2 hypomorphic mutant mice. Furthermore, the data show that transgenic rescue by GATA-2 reverses the rostral outgrowth of the UB. We also provide evidence for a GATA-2–BMP4 epistatic relationship by demonstrating that reporter gene expression from a Bmp4 bacterial artificial chromosome (BAC) transgene is altered in GATA2 hypomorphs; furthermore, UG4-directed BMP4 expression in the mutants leads to reduced incidence of megaureters. These results demonstrate that GATA-2 expression in the caudal urogenital mesenchyme as directed by the UG4 enhancer is crucial for proper development of the urinary tract and that its regulation of BMP4 expression is a critical aspect of this function.
Tomofumi Hoshino - One of the best experts on this subject based on the ideXlab platform.
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spiral ganglion cell degeneration induced deafness as a consequence of reduced gata factor activity
Genes to Cells, 2019Co-Authors: Masayuki Yamamoto, Jun Takai, Tomofumi Hoshino, Tsumoru Terunuma, Satoshi Uemura, Yasuhiro Nakamura, Michito Hamada, Satoru Takahashi, James Douglas EngelAbstract:Zinc-finger transcription factors GATA2 and GATA3 are both expressed in the developing inner ear, although their overlapping versus distinct activities in adult definitive inner ear are not well understood. We show here that GATA2 and GATA3 are co-expressed in cochlear spiral ganglion cells and redundantly function in the maintenance of spiral ganglion cells and auditory neural circuitry. Notably, GATA2 and Gata3 compound heterozygous mutant mice had a diminished number of spiral ganglion cells due to enhanced apoptosis, which resulted in progressive hearing loss. The decrease in spiral ganglion cellularity was associated with lowered expression of neurotrophin receptor TrkC that is an essential factor for spiral ganglion cell survival. We further show that GATA2 null mutants that additionally bear a GATA2 YAC (yeast artificial chromosome) that counteracts the lethal hematopoietic deficiency due to complete GATA2 loss nonetheless failed to complement the deficiency in neonatal spiral ganglion neurons. Furthermore, cochlea-specific GATA2 deletion mice also had fewer spiral ganglion cells and resultant hearing impairment. These results show that GATA2 and GATA3 redundantly function to maintain spiral ganglion cells and hearing. We propose possible mechanisms underlying hearing loss in human GATA2- or GATA3-related genetic disorders.
Jun Takai - One of the best experts on this subject based on the ideXlab platform.
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spiral ganglion cell degeneration induced deafness as a consequence of reduced gata factor activity
Genes to Cells, 2019Co-Authors: Masayuki Yamamoto, Jun Takai, Tomofumi Hoshino, Tsumoru Terunuma, Satoshi Uemura, Yasuhiro Nakamura, Michito Hamada, Satoru Takahashi, James Douglas EngelAbstract:Zinc-finger transcription factors GATA2 and GATA3 are both expressed in the developing inner ear, although their overlapping versus distinct activities in adult definitive inner ear are not well understood. We show here that GATA2 and GATA3 are co-expressed in cochlear spiral ganglion cells and redundantly function in the maintenance of spiral ganglion cells and auditory neural circuitry. Notably, GATA2 and Gata3 compound heterozygous mutant mice had a diminished number of spiral ganglion cells due to enhanced apoptosis, which resulted in progressive hearing loss. The decrease in spiral ganglion cellularity was associated with lowered expression of neurotrophin receptor TrkC that is an essential factor for spiral ganglion cell survival. We further show that GATA2 null mutants that additionally bear a GATA2 YAC (yeast artificial chromosome) that counteracts the lethal hematopoietic deficiency due to complete GATA2 loss nonetheless failed to complement the deficiency in neonatal spiral ganglion neurons. Furthermore, cochlea-specific GATA2 deletion mice also had fewer spiral ganglion cells and resultant hearing impairment. These results show that GATA2 and GATA3 redundantly function to maintain spiral ganglion cells and hearing. We propose possible mechanisms underlying hearing loss in human GATA2- or GATA3-related genetic disorders.
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Derepression of the DNA Methylation Machinery of the Gata1 Gene Triggers the Differentiation Cue for Erythropoiesis
Molecular and cellular biology, 2017Co-Authors: Jun Takai, James Douglas Engel, Takashi Moriguchi, Mikiko Suzuki, Akihito Otsuki, Fumiki Katsuoka, Saori Katayama, Masahiro Nezu, Masayuki YamamotoAbstract:GATA1 is a critical regulator of erythropoiesis. While the mechanisms underlying the high-level expression of GATA1 in maturing erythroid cells have been studied extensively, the initial activation of the Gata1 gene in early hematopoietic progenitors remains to be elucidated. We previously identified a hematopoietic stem and progenitor cell (HSPC)-specific silencer element (the Gata1 methylation-determining region [G1MDR]) that recruits DNA methyltransferase 1 (Dnmt1) and provokes methylation of the Gata1 gene enhancer. In the present study, we hypothesized that removal of the G1MDR-mediated silencing machinery is the molecular basis of the initial activation of the Gata1 gene and erythropoiesis. To address this hypothesis, we generated transgenic mouse lines harboring a Gata1 bacterial artificial chromosome in which the G1MDR was deleted. The mice exhibited abundant GATA1 expression in HSPCs, in a GATA2-dependent manner. The ectopic GATA1 expression repressed GATA2 transcription and induced erythropoiesis and apoptosis of HSPCs. Furthermore, genetic deletion of Dnmt1 in HSPCs activated Gata1 expression and depleted HSPCs, thus recapitulating the HSC phenotype associated with GATA1 gain of function. These results demonstrate that the G1MDR holds the key to HSPC maintenance and suggest that release from this suppressive mechanism is a fundamental requirement for subsequent initiation of erythroid differentiation.
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Progenitor stage-specific activity of a cis-acting double GATA motif for Gata1 gene expression.
Molecular and cellular biology, 2014Co-Authors: Takashi Moriguchi, Kinuko Ohneda, Jun Takai, Mikiko Suzuki, Masayuki YamamotoAbstract:GATA1 is a master regulator of erythropoiesis, expression of which is regulated by multiple discrete cis-acting elements. In this study, we examine the activity of a promoter-proximal double GATA (dbGATA) motif, using a Gata1 bacterial artificial chromosome (BAC)-transgenic green fluorescent protein (GFP) reporter (G1BAC-GFP) mouse system. Deletion of the dbGATA motif led to significant reductions in GFP expression in hematopoietic progenitors, while GFP expression was maintained in erythroblasts. Consistently, in mice with a germ line deletion of the dbGATA motif (Gata1(ΔdbGATA) mice), GATA1 expression in progenitors was significantly decreased. The suppressed GATA1 expression was associated with a compensatory increase in GATA2 levels in progenitors. When we crossed Gata1(ΔdbGATA) mice with GATA2 hypomorphic mutant mice (GATA2(fGN/fGN) mice), the Gata1(ΔdbGATA)::GATA2(fGN/fGN) compound mutant mice succumbed to a significant decrease in the progenitor population, whereas both groups of single mutant mice maintained progenitors and survived to adulthood, indicating the functional redundancy between GATA1 and GATA2 in progenitors. Meanwhile, the effects of the dbGATA site deletion on Gata1 expression were subtle in erythroblasts, which showed increased GATA1 binding and enhanced accumulation of active histone marks around the 1st-intron GATA motif of the ΔdbGATA locus. These results thus reveal a novel role of the dbGATA motif in the maintenance of Gata1 expression in hematopoietic progenitors and a functional compensation between the dbGATA site and the 1st-intron GATA motif in erythroblasts.
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GATA2 Regulates Body Water Homeostasis through Maintaining Aquaporin 2 Expression in Renal Collecting Ducts
Molecular and cellular biology, 2014Co-Authors: Takashi Moriguchi, James Douglas Engel, Jun Takai, Hironori Satoh, Tomokazu Souma, Naoki Morito, Masayuki YamamotoAbstract:The transcription factor GATA2 plays pivotal roles in early renal development, but its distribution and physiological functions in adult kidney are largely unknown. We examined the GATA2 expression pattern in the adult kidney by tracing green fluorescent protein (GFP) fluorescence in GATA2(GFP/+) mice that recapitulate endogenous GATA2 expression and found a robust GFP expression specifically in the renal medulla. Upon purification of the GFP-positive cells, we found that collecting duct (CD)-specific markers, including aquaporin 2 (Aqp2), an important channel for water reabsorption from urine, were abundantly expressed. To address the physiological function of GATA2 in the CD cells, we generated renal tubular cell-specific GATA2-deficient mice (GATA2-CKO) by crossing GATA2 floxed mice with inducible Pax8-Cre mice. We found that the GATA2-CKO mice showed a significant decrease in Aqp2 expression. The GATA2-CKO mice exhibited high 24-h urine volume and low urine osmolality, two important signs of diabetes insipidus. We introduced biotin-tagged GATA2 into a mouse CD-derived cell line and conducted chromatin pulldown assays, which revealed direct GATA2 binding to conserved GATA motifs in the Aqp2 promoter region. A luciferase reporter assay using an Aqp2 promoter-reporter showed that GATA2 trans activates Aqp2 through the GATA motifs. These results demonstrate that GATA2 regulates the Aqp2 gene expression in CD cells and contributes to the maintenance of the body water homeostasis.
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the gata1 5 region harbors distinct cis regulatory modules that direct gene activation in erythroid cells and gene inactivation in hscs
Blood, 2013Co-Authors: Jun Takai, Kinuko Ohneda, Takashi Moriguchi, Mikiko Suzuki, Masayuki YamamotoAbstract:GATA1 is a master regulator of hematopoietic differentiation, but Gata1 expression is inactivated in hematopoietic stem cells (HSCs). Using a bacterial artificial chromosome containing the Gata1 gene modified with green fluorescent protein (GFP) reporter, we explored the function of the 3.7-kb Gata1 upstream region (GdC region) that harbors 3 core cis-elements: Gata1 hematopoietic enhancer, double GATA-motif, and CACCC-motif. Transgenic GFP expression directed by the Gata1-BAC faithfully recapitulated the endogenous Gata1 expression pattern. However, deletion of the GdC-region eliminated reporter expression in all hematopoietic cells. To test whether the combination of the core cis-elements represents the regulatory function of the GdC-region, we replaced the region with a 659-bp minigene that linked the three cis-elements (MG-GFP). The GFP reporter expression directed by the MG-GFP BAC fully recapitulated the erythroid-megakaryocytic Gata1 expression. However, the GFP expression was aberrantly increased in the HSCs and was associated with decreases in DNA methylation and abundant GATA2 binding to the transgenic MG-GFP allele. The 3.2-kb sequences interspaced between the Gata1 hematopoietic enhancer and the double GATA-motif were able to recruit DNA methyltransferase 1, thereby exerting a cis-repressive function in the HSC-like cell line. These results indicate that the 3.2-kb interspacing sequences inactivate Gata1 by maintaining DNA-methylation in the HSCs.
Atsushi Tanabe - One of the best experts on this subject based on the ideXlab platform.
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critical roles for pu 1 gata1 and GATA2 in the expression of human fceri on mast cells pu 1 and gata1 transactivate fcer1a and GATA2 transactivates fcer1a and ms4a2
Journal of Immunology, 2014Co-Authors: Eisuke Inage, Yosuke Baba, Takuya Yashiro, Kazumi Kasakura, Ryuyo Suzuki, Mutsuko Hara, Nobuhiro Nakano, Atsushi TanabeAbstract:The high-affinity IgE receptor, FceRI, which is composed of α-, β-, and γ-chains, plays an important role in IgE-mediated allergic responses. In the current study, involvement of the transcription factors, PU.1, GATA1, and GATA2, in the expression of FceRI on human mast cells was investigated. Transfection of small interfering RNAs (siRNAs) against PU.1, GATA1, and GATA2 into the human mast cell line, LAD2, caused significant downregulation of cell surface expression of FceRI. Quantification of the mRNA levels revealed that PU.1, GATA1, and GATA2 siRNAs suppressed the α transcript, whereas the amount of β mRNA was reduced in only GATA2 siRNA transfectants. In contrast, γ mRNA levels were not affected by any of the knockdowns. Chromatin immunoprecipitation assay showed that significant amounts of PU.1, GATA1, and GATA2 bind to the promoter region of FCER1A (encoding FceRIα) and that GATA2 binds to the promoter of MS4A2 (encoding FceRIβ). Luciferase assay and EMSA showed that GATA2 transactivates the MS4A2 promoter via direct binding. These knockdowns of transcription factors also suppressed the IgE-mediated degranulation activity of LAD2. Similarly, all three knockdowns suppressed FceRI expression in primary mast cells, especially PU.1 siRNA and GATA2 siRNA, which target FceRIα and FceRIβ, respectively. From these results, we conclude that PU.1 and GATA1 are involved in FceRIα transcription through recruitment to its promoter, whereas GATA2 positively regulates FceRIβ transcription. Suppression of these transcription factors leads to downregulation of FceRI expression and IgE-mediated degranulation activity. Our findings will contribute to the development of new therapeutic approaches for FceRI-mediated allergic diseases.
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Critical Roles for PU.1, GATA1, and GATA2 in the Expression of Human FcεRI on Mast Cells: PU.1 and GATA1 Transactivate FCER1A , and GATA2 Transactivates FCER1A and MS4A2
Journal of immunology (Baltimore Md. : 1950), 2014Co-Authors: Eisuke Inage, Yosuke Baba, Takuya Yashiro, Kazumi Kasakura, Ryuyo Suzuki, Mutsuko Hara, Atsushi Tanabe, Nobuhiro Nakano, Keisuke Oboki, Kenji MatsumotoAbstract:The high-affinity IgE receptor, FceRI, which is composed of α-, β-, and γ-chains, plays an important role in IgE-mediated allergic responses. In the current study, involvement of the transcription factors, PU.1, GATA1, and GATA2, in the expression of FceRI on human mast cells was investigated. Transfection of small interfering RNAs (siRNAs) against PU.1, GATA1, and GATA2 into the human mast cell line, LAD2, caused significant downregulation of cell surface expression of FceRI. Quantification of the mRNA levels revealed that PU.1, GATA1, and GATA2 siRNAs suppressed the α transcript, whereas the amount of β mRNA was reduced in only GATA2 siRNA transfectants. In contrast, γ mRNA levels were not affected by any of the knockdowns. Chromatin immunoprecipitation assay showed that significant amounts of PU.1, GATA1, and GATA2 bind to the promoter region of FCER1A (encoding FceRIα) and that GATA2 binds to the promoter of MS4A2 (encoding FceRIβ). Luciferase assay and EMSA showed that GATA2 transactivates the MS4A2 promoter via direct binding. These knockdowns of transcription factors also suppressed the IgE-mediated degranulation activity of LAD2. Similarly, all three knockdowns suppressed FceRI expression in primary mast cells, especially PU.1 siRNA and GATA2 siRNA, which target FceRIα and FceRIβ, respectively. From these results, we conclude that PU.1 and GATA1 are involved in FceRIα transcription through recruitment to its promoter, whereas GATA2 positively regulates FceRIβ transcription. Suppression of these transcription factors leads to downregulation of FceRI expression and IgE-mediated degranulation activity. Our findings will contribute to the development of new therapeutic approaches for FceRI-mediated allergic diseases.
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GATA2 is a critical transactivator for the human il1rl1 st2 promoter in mast cells basophils opposing roles for GATA2 and gata1 in human il1rl1 st2 gene expression
Journal of Biological Chemistry, 2012Co-Authors: Yosuke Baba, Keiko Maeda, Takuya Yashiro, Eisuke Inage, Kazumi Kasakura, Ryuyo Suzuki, Francois Niyonsaba, Mutsuko Hara, Atsushi Tanabe, Hideoki OgawaAbstract:The IL1RL1/ST2 gene encodes a receptor for IL-33. Signaling from IL1RL1/ST2 induced by IL-33 binding was recently identified as a modulator of the Th2 response. The target cells for IL-33 are restricted in some hematopoietic lineages, including mast cells, basophils, eosinophils, Th2 cells, natural killer cells, and dendritic cells. To clarify the molecular mechanisms of cell type-specific IL1RL1/ST2 expression in mast cells and basophils, transcriptional regulation of the human IL1RL1/ST2 promoter was investigated using the mast cell line LAD2 and the basophilic cell line KU812. Reporter assays suggested that two GATA motifs just upstream of the transcription start site in the ST2 promoter are critical for transcriptional activity. These two GATA motifs possess the capacity to bind GATA1 and GATA2 in EMSA. ChIP assay showed that GATA2, but not GATA1, bound to the ST2 promoter in LAD2 cells and that histone H3 at the ST2 promoter was acetylated in LAD2 cells, whereas binding of GATA1 and GATA2 to the ST2 promoter was detected in KU812 cells. Knockdown of GATA2 mRNA by siRNA reduced ST2 mRNA levels in KU812 and LAD2 cells and ST2 protein levels in LAD2 cells; in contrast, GATA1 siRNA transfection up-regulated ST2 mRNA levels in KU812 cells. The ST2 promoter was transactivated by GATA2 and repressed by GATA1 in coexpression analysis. When these siRNAs were introduced into human peripheral blood basophils, GATA2 siRNA reduced ST2 mRNA, whereas GATA1 siRNA up-regulated ST2 mRNA. These results indicate that GATA2 and GATA1 positively and negatively control human ST2 gene transcription, respectively.
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GATA2 Is a Critical Transactivator for the Human IL1RL1/ST2 Promoter in Mast Cells/Basophils OPPOSING ROLES FOR GATA2 and GATA1 IN HUMAN IL1RL1/ST2 GENE EXPRESSION
The Journal of biological chemistry, 2012Co-Authors: Yosuke Baba, Keiko Maeda, Takuya Yashiro, Eisuke Inage, Kazumi Kasakura, Ryuyo Suzuki, Francois Niyonsaba, Mutsuko Hara, Atsushi Tanabe, Hideoki OgawaAbstract:The IL1RL1/ST2 gene encodes a receptor for IL-33. Signaling from IL1RL1/ST2 induced by IL-33 binding was recently identified as a modulator of the Th2 response. The target cells for IL-33 are restricted in some hematopoietic lineages, including mast cells, basophils, eosinophils, Th2 cells, natural killer cells, and dendritic cells. To clarify the molecular mechanisms of cell type-specific IL1RL1/ST2 expression in mast cells and basophils, transcriptional regulation of the human IL1RL1/ST2 promoter was investigated using the mast cell line LAD2 and the basophilic cell line KU812. Reporter assays suggested that two GATA motifs just upstream of the transcription start site in the ST2 promoter are critical for transcriptional activity. These two GATA motifs possess the capacity to bind GATA1 and GATA2 in EMSA. ChIP assay showed that GATA2, but not GATA1, bound to the ST2 promoter in LAD2 cells and that histone H3 at the ST2 promoter was acetylated in LAD2 cells, whereas binding of GATA1 and GATA2 to the ST2 promoter was detected in KU812 cells. Knockdown of GATA2 mRNA by siRNA reduced ST2 mRNA levels in KU812 and LAD2 cells and ST2 protein levels in LAD2 cells; in contrast, GATA1 siRNA transfection up-regulated ST2 mRNA levels in KU812 cells. The ST2 promoter was transactivated by GATA2 and repressed by GATA1 in coexpression analysis. When these siRNAs were introduced into human peripheral blood basophils, GATA2 siRNA reduced ST2 mRNA, whereas GATA1 siRNA up-regulated ST2 mRNA. These results indicate that GATA2 and GATA1 positively and negatively control human ST2 gene transcription, respectively.