Project description:GATA-binding protein 3 (GATA3) acts as the master transcription factor for type 2 T helper (Th2) cell differentiation and function. However, it is still elusive how GATA3 function is precisely regulated in Th2 cells. Here, we report that the transcription factor B cell lymphoma 11b (Bcl11b), a previously unknown component of GATA3 transcriptional complex, is involved in GATA3-mediated gene regulation. Bcl11b binds to GATA3 through protein-protein interaction, and they co-localize at many important cis-regulatory elements in Th2 cells. The expression of type 2 cytokines, including IL-4, IL-5 and IL-13, is up-regulated in Bcl11b-deficient Th2 cells both in vitro and in vivo; such up-regulation is completely GATA3-dependent. Genome-wide analyses of Bcl11b- and GATA3-regulated gene (from RNA-Seq), co-binding pattern (from ChIP-Seq), and Bcl11b-mediated epigenetic changes (in H3K27ac and DHSs) suggest that GATA3/Bcl11b complex is involved in limiting Th2 gene expression, as well as in inhibiting non-Th2 gene expression. Thus, Bcl11b controls both GATA3-mediated gene activation and repression in Th2 cells.
Project description:GATA-binding protein 3 (GATA3) acts as the master transcription factor for type 2 T helper (Th2) cell differentiation and function. However, it is still elusive how GATA3 function is precisely regulated in Th2 cells. Here, we report that the transcription factor B cell lymphoma 11b (Bcl11b), a previously unknown component of GATA3 transcriptional complex, is involved in GATA3-mediated gene regulation. Bcl11b binds to GATA3 through protein-protein interaction, and they co-localize at many important cis-regulatory elements in Th2 cells. The expression of type 2 cytokines, including IL-4, IL-5 and IL-13, is up-regulated in Bcl11b-deficient Th2 cells both in vitro and in vivo; such up-regulation is completely GATA3-dependent. Genome-wide analyses of Bcl11b- and GATA3-regulated gene (from RNA-Seq), co-binding pattern (from ChIP-Seq), and Bcl11b-mediated epigenetic changes (in H3K27ac and DHSs) suggest that GATA3/Bcl11b complex is involved in limiting Th2 gene expression, as well as in inhibiting non-Th2 gene expression. Thus, Bcl11b controls both GATA3-mediated gene activation and repression in Th2 cells.
Project description:Naïve CD4+ T-helper cells differentiate into Th2 effector cells during asthma and helminth (worm) infection. Here, we report that mice lacking the transcription factor Bcl11b in mature CD4+ T-cells are incapable of mounting an effective Th2 response in asthma and worm infection, with a major reduction of Th2 cytokine secretion and GATA3 expression. We found that Bcl11b exerts its role in Th2 differentiation through several avenues: (1) association with intronic regions at the Gata3 locus, sustaining GATA3 expression; (2) binding to and restricting chromatin accessibility at the Il4 silencer, located at hypersensitivity site (HS) IV; and (3) restricting Runx3 expression by association with a regulatory region 5’ of Runx3. Thus, in the absence of Bcl11b, the reduction in GATA3 levels combined with increased Runx3 levels and activity at Il4 HS IV silencer and consequently diminished IL-4 expression. This results in reduced chromatin opening at the Th2 locus control region (LCR), Il13 and Il5 promoters, subsequently preventing expression of Th2 cytokine genes and Th2 differentiation. Our results establish a novel role for Bcl11b in the regulatory loop critical for licensing the Th2 program in vivo.
Project description:Naïve CD4+ T-helper cells differentiate into Th2 effector cells during asthma and helminth (worm) infection. Here, we report that mice lacking the transcription factor Bcl11b in mature CD4+ T-cells are incapable of mounting an effective Th2 response in asthma and worm infection, with a major reduction of Th2 cytokine secretion and GATA3 expression. We found that Bcl11b exerts its role in Th2 differentiation through several avenues: (1) association with intronic regions at the Gata3 locus, sustaining GATA3 expression; (2) binding to and restricting chromatin accessibility at the Il4 silencer, located at hypersensitivity site (HS) IV; and (3) restricting Runx3 expression by association with a regulatory region 5’ of Runx3. Thus, in the absence of Bcl11b, the reduction in GATA3 levels combined with increased Runx3 levels and activity at Il4 HS IV silencer and consequently diminished IL-4 expression. This results in reduced chromatin opening at the Th2 locus control region (LCR), Il13 and Il5 promoters, subsequently preventing expression of Th2 cytokine genes and Th2 differentiation. Our results establish a novel role for Bcl11b in the regulatory loop critical for licensing the Th2 program in vivo.
Project description:Naïve CD4+ T-helper cells differentiate into Th2 effector cells during asthma and helminth (worm) infection. Here, we report that mice lacking the transcription factor Bcl11b in mature CD4+ T-cells are incapable of mounting an effective Th2 response in asthma and worm infection, with a major reduction of Th2 cytokine secretion and GATA3 expression. We found that Bcl11b exerts its role in Th2 differentiation through several avenues: (1) association with intronic regions at the Gata3 locus, sustaining GATA3 expression; (2) binding to and restricting chromatin accessibility at the Il4 silencer, located at hypersensitivity site (HS) IV; and (3) restricting Runx3 expression by association with a regulatory region 5’ of Runx3. Thus, in the absence of Bcl11b, the reduction in GATA3 levels combined with increased Runx3 levels and activity at Il4 HS IV silencer and consequently diminished IL-4 expression. This results in reduced chromatin opening at the Th2 locus control region (LCR), Il13 and Il5 promoters, subsequently preventing expression of Th2 cytokine genes and Th2 differentiation. Our results establish a novel role for Bcl11b in the regulatory loop critical for licensing the Th2 program in vivo.
Project description:Functionally polarized CD4+ T helper (Th) cells such as Th1, Th2 and Th17 cells are central to the regulation of acquired immunity. However, the molecular mechanisms governing the maintenance of the polarized functions of Th cells remain unclear. GATA3, a master regulator of Th2 cell differentiation, initiates the expressions of Th2 cytokine genes and other Th2-specific genes. GATA3 also plays important roles in maintaining Th2 cell function and in continuous chromatin remodeling of Th2 cytokine gene loci. However, it is unclear whether continuous expression of GATA3 is required to maintain the expression of various other Th2-specific genes. In this report, genome-wide DNA gene expression profiling revealed that GATA3 expression is critical for the expression of a certain set of Th2-specific genes. We demonstrated that GATA3 dependency is reduced for some Th2-specific genes in fully developed Th2 cells compared to that observed in effector Th2 cells, whereas it is unchanged for other genes. Moreover, effects of a loss of GATA3 expression in Th2 cells on the expression of cytokine and cytokine receptor genes were examined in detail. A critical role of GATA3 in the regulation of Th2-specific gene expression is confirmed in in vivo generated antigen-specific memory Th2 cells. Therefore, GATA3 is required for the continuous expression of the majority of Th2-specific genes involved in maintaining the Th2 cell identity. Mock-transfected and GATA3 siRNA-transfected Th2 and Th2-4th cells are profiled for mRNA expression
Project description:Functionally polarized CD4+ T helper (Th) cells such as Th1, Th2 and Th17 cells are central to the regulation of acquired immunity. However, the molecular mechanisms governing the maintenance of the polarized functions of Th cells remain unclear. GATA3, a master regulator of Th2 cell differentiation, initiates the expressions of Th2 cytokine genes and other Th2-specific genes. GATA3 also plays important roles in maintaining Th2 cell function and in continuous chromatin remodeling of Th2 cytokine gene loci. However, it is unclear whether continuous expression of GATA3 is required to maintain the expression of various other Th2-specific genes. In this report, genome-wide DNA gene expression profiling revealed that GATA3 expression is critical for the expression of a certain set of Th2-specific genes. We demonstrated that GATA3 dependency is reduced for some Th2-specific genes in fully developed Th2 cells compared to that observed in effector Th2 cells, whereas it is unchanged for other genes. Moreover, effects of a loss of GATA3 expression in Th2 cells on the expression of cytokine and cytokine receptor genes were examined in detail. A critical role of GATA3 in the regulation of Th2-specific gene expression is confirmed in in vivo generated antigen-specific memory Th2 cells. Therefore, GATA3 is required for the continuous expression of the majority of Th2-specific genes involved in maintaining the Th2 cell identity.
Project description:Differentiation of naive CD4 T cells into type 2 helper (Th2) cells is accompanied by chromatin remodeling and increased expression of a set of Th2-specific genes including those encoding Th2 cytokines. IL-4-mediated STAT6 activation induces high levels of transcription of GATA3, a master regulator of Th2 cell differentiation, and enforced expression of GATA3 induces Th2 cytokine expression. However, it remains unclear whether the expression of other Th2-specific genes is induced directly by GATA3. A genome-wide unbiased ChIP-seq analysis revealed that GATA3 bound to 1,279 genes selectively in Th2 cells, and 101 genes in both Th1 and Th2 cells. Simultaneously, we identified 26 highly Th2-specific STAT6-dependent inducible genes by a DNA microarray analysis-based three-step selection processes, and among them 17 genes showed GATA3 binding. We assessed dependency on GATA3 for the transcription of these 26 Th2-specific genes, and 10 genes showed increased transcription in a GATA3-dependent manner while 16 genes showed no significant responses. The transcription of the 16 GATA3-nonresponding genes was clearly increased by the introduction of an active form of STAT6, STAT6VT. Therefore, although GATA3 has been recognized as a master regulator of Th2 cell differentiation, many Th2-specific genes are not regulated by GATA3 itself but in collaboration with STAT6. Th1 and Th2 subsets are profiled for mRNA expression Examination of GATA3-binding and 3 different histone modifications in Th1 and Th2 cells.
Project description:Post-translational modifications of histones are well-established epigenetic modifications that play an important role in gene expression and regulation. These modifications are partly mediated by the Trithorax group (TrxG) complex, which regulates the induction or maintence of gene transcription. We investigated the role of Menin, a component of the TrxG complex, in the acquisition and maintenance of T helper type 2 (Th2) cell identity using T cell-specific Menin-deficient mice. Our gene expression analysis revealed that Menin was involved in the maintenance of the high level expression of the previously identified Th2-specific genes rather than the induction of these genes. This result suggests a role of Menin in the maintenance of Th2 cell identity. Menin directly bound to the Gata3 gene locus, and this Menin-Gata3 axis appeared to form a core unit of the Th2-specific gene regulatory network. Consistent with the phenotype of Menin-deficient Th2 cells observed in vitro, Menin deficiency resulted in the attenuation of effector Th2 cell-induced airway inflammation. In addition, in memory Th2 cells, Menin was found to play an important role in the maintenance of the expression of Th2-specific genes, including Gata3, Il4, and Il13. Consequently, Menin-deficient memory Th2 cells showed an impaired abiliy to recruit eosinophils to the lung, resulting in the attenuation of memory Th2 cell-induced airway inflammation. This study confirmed the critical role of Menin in Th2 cell-mediated immune responses.
Project description:Differentiation of naive CD4 T cells into type 2 helper (Th2) cells is accompanied by chromatin remodeling and increased expression of a set of Th2-specific genes including those encoding Th2 cytokines. IL-4-mediated STAT6 activation induces high levels of transcription of GATA3, a master regulator of Th2 cell differentiation, and enforced expression of GATA3 induces Th2 cytokine expression. However, it remains unclear whether the expression of other Th2-specific genes is induced directly by GATA3. A genome-wide unbiased ChIP-seq analysis revealed that GATA3 bound to 1,279 genes selectively in Th2 cells, and 101 genes in both Th1 and Th2 cells. Simultaneously, we identified 26 highly Th2-specific STAT6-dependent inducible genes by a DNA microarray analysis-based three-step selection processes, and among them 17 genes showed GATA3 binding. We assessed dependency on GATA3 for the transcription of these 26 Th2-specific genes, and 10 genes showed increased transcription in a GATA3-dependent manner while 16 genes showed no significant responses. The transcription of the 16 GATA3-nonresponding genes was clearly increased by the introduction of an active form of STAT6, STAT6VT. Therefore, although GATA3 has been recognized as a master regulator of Th2 cell differentiation, many Th2-specific genes are not regulated by GATA3 itself but in collaboration with STAT6.