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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The transcription factors GATA-1, GATA-2, and GATA-3 were found to be expressed in several mouse and rat mast cell lines that contain mast cell carboxypeptidase A (MC-CPA) and other proteases in their cytoplasmic granules. GATA-1 mRNA was not detected in P815 cells, an immature mouse mastocytoma-derived cell line that lacks electron-dense granules and has low levels of secretory granule proteases. Because the 5'-flanking regions of the mouse and human MC-CPA genes contained a conserved GATA-binding motif 51 base pairs upstream of their translation initiation sites, the ability of GATA-binding proteins to regulate the promoter activity of the MC-CPA gene was examined in rat basophilic leukemia cells, mouse P815 cells, and transfected mouse P815 cells that expressed GATA-1. In all three mast cell lines, the promoter activity of the MC-CPA gene depended on the GATA binding site. GATA-1, GATA-2, and GATA-3 are thus the first DNA-binding proteins identified in mast cells which regulate the promoter activity of a gene that encodes a secretory granule protease.
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PMID:GATA-binding transcription factors in mast cells regulate the promoter of the mast cell carboxypeptidase A gene. 174 88

The GATA 'zinc-finger' transcription factors are thought to have important roles in the control of hematopoiesis. GATA-1 and GATA-2 are found in the erythroid, mast cell, and megakaryocytic lineages, and GATA-3 in T lymphocytes. GATA-1 is required for erythroid development and has recently been shown by gene transfer to direct megakaryocytic differentiation of the primitive myeloid cell line 416B. Here we show that enforced expression in 416B cells of either the GATA-2 or GATA-3 gene also induces megakaryocytic differentiation, as assessed by cellular morphology, acetylcholinesterase activity, polyploid DNA content, and loss of Mac-1 expression. No erythroid or mast cell differentiation was found. Unexpectedly, the level of endogenous GATA-1 mRNA had increased 20- to 30-fold among the transfectants, whereas that of GATA-2 mRNA was unaltered and endogenous GATA-3 transcripts remained undetectable. This finding suggests that GATA-2 and GATA-3 lie upstream of GATA-1 in a regulatory hierarchy and that, in 416B cells, GATA-1 may mediate the phenotypic changes induced by GATA-2 or GATA-3. Furthermore, 416B cells treated with the DNA demethylating agent 5-azacytidine underwent megakaryocytic differentiation accompanied by a marked increase in the level of GATA-1 mRNA but not that of GATA-2 or GATA-3. These results strongly implicate GATA factors in megakaryocytic differentiation and suggest that, at least for 416B cells, GATA-1 is a dominant regulator of maturation along this lineage.
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PMID:Megakaryocytic differentiation induced in 416B myeloid cells by GATA-2 and GATA-3 transgenes or 5-azacytidine is tightly coupled to GATA-1 expression. 768 71

The GATA-1 and GATA-2 transcription factors, which each contain two homologous zinc fingers, are important hematopoietic regulators expressed within the erythroid, mast cell, and megakaryocytic lineages. Enforced expression of either factor in the primitive myeloid line 416B induces megakaryocytic differentiation. The features of their structure required for this activity have been explored. The ability of 12 GATA-1 mutants to promote 416B maturation was compared with their DNA-binding activity and transactivation potential. Differentiation did not require any of the seven serine residues that are phosphorylated in vivo, an N-terminal region bearing the major transactivation domain, or a C-terminal segment beyond the fingers. Removal of a consensus nuclear localization signal following the second finger did not block differentiation or nuclear translocation. The N-terminal finger was also dispensable, although its removal attenuated differentiation. In contrast, the C-terminal finger was essential, underscoring its distinct function. Remarkably, only 69 residues spanning the C-terminal finger were required to induce limited megakaryocytic differentiation. Analysis of three GATA-2 mutants led to the same conclusion. Endogenous GATA-1 mRNA was induced by most mutants and may contribute to differentiation. Because the GATA-1 C-terminal finger could bind its target site but not transactivate a minimal reporter, it may direct megakaryocytic maturation by derepressing specific genes and/or by interacting with another protein which provides the transactivation function.
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PMID:The C-terminal zinc finger of GATA-1 or GATA-2 is sufficient to induce megakaryocytic differentiation of an early myeloid cell line. 782 32

GATA-1 is a zinc-finger transcription factor believed to play an important role in gene regulation during the development of erythroid cells, megakaryocytes and mast cells. Other members of the GATA family, which can bind to the same DNA sequence motif, are co-expressed in several of these hemopoietic lineages, raising the possibility of overlap in function. To examine the specific roles of GATA-1 in hematopoietic cell differentiation, we have tested the ability of embryonic stem cells, carrying a targeted mutation in the X-linked GATA-1 gene, to contribute to various blood cell types when used to produce chimeric embryos or mice. Previously, we reported that GATA-1- mutant cells failed to contribute to the mature red blood cell population, indicating a requirement for this factor at some point in the erythroid lineage (L. Pevny et al., (1991) Nature 349, 257-260). In this study, we have used in vitro colony assays to identify the stage at which mutant erythroid cells are affected, and to examine the requirement for GATA-1 in other lineages. We found that the development of erythroid progenitors in embryonic yolk sacs was unaffected by the mutation, but that the cells failed to mature beyond the proerythroblast stage, an early point in terminal differentiation. GATA-1- colonies contained phenotypically normal macrophages, neutrophils and megakaryocytes, indicating that GATA-1 is not required for the in vitro differentiation of cells in these lineages. GATA-1- megakaryocytes were abnormally abundant in chimeric fetal livers, suggesting an alteration in the kinetics of their formation or turnover. The lack of a block in terminal megakaryocyte differentiation was shown by the in vivo production of platelets expressing the ES cell-derived GPI-1C isozyme. The role of GATA-1 in mast cell differentiation was examined by the isolation of clonal mast cell cultures from chimeric fetal livers. Mutant and wild-type mast cells displayed similar growth and histochemical staining properties after culture under conditions that promote the differentiation of cells resembling mucosal or serosal mast cells. Thus, the mast and megakaryocyte lineages, in which GATA-1 and GATA-2 are co-expressed, can complete their maturation in the absence of GATA-1, while erythroid cells, in which GATA-1 is the predominant GATA factor, are blocked at a relatively early stage of maturation.
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PMID:Development of hematopoietic cells lacking transcription factor GATA-1. 786 97

We have established a unique variant cell line, MC/9.IL-4, which continuously proliferates in the presence of interleukin-4 (IL-4), from a murine interleukin-3 (IL-3)-dependent mast cell line, MC/9 (referred to as MC/9.IL-3). Compared with MC/9.IL-3 cells, MC/9.IL-4 cells are smaller, lack cytoplasmic granules and metachromasia, carry a very small amount of histamine, and express fewer high-affinity IgE receptors (IgERs) and IL-3 receptors. To further characterize MC/9.IL-4, we developed a novel method to enrich cell type-specific cDNAs by cDNA library subtraction and applied it for MC/9.IL-3 versus MC/9.IL-4. Sequence analysis of cDNA clones isolated by this technique showed that MC/9.IL-4 cells specifically express CD8 alpha and expression of mast cell-specific proteases and major histocompatibility complex class II (MHCII) is considerably decreased. It was also noted that responsiveness to the IL-3-agonistic antibody F9 and expression of the transcription factor GATA-2 is diminished in MC/9.IL-4, indicating that MC/9.IL-4 have lost major characteristics of the bone marrow-derived cultured mast cells. Because other T-cell marker antigens, CD8 beta, CD4, Thy-1, were not detected on MC/9.IL-4 cells, MC/9.IL-4 cells may represent an unknown class of hematopoietic cells that express CD8 alpha. This cell line will be useful in studies of IL-4-mediated signal transduction, as well as transcriptional regulation of mast cell characteristic genes. This study also demonstrates the effective use of the cDNA library subtraction strategy to characterize unknown types of hematopoietic cells at the molecular level.
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PMID:Characterization of cell phenotype by a novel cDNA library subtraction system: expression of CD8 alpha in a mast cell-derived interleukin-4-dependent cell line. 801 17

Interleukin 4 (IL-4), a critical immunoregulatory cytokine, is produced by a subset of T lymphocytes and cells of the mast cell/basophil lineage. There are cell-specific differences in the regulatory elements that control IL-4 transcription in these two cell types. A 683-bp Bgl II fragment, located within the second intron of the murine IL-4 gene, was previously shown to exhibit mast cell-specific enhancer activity. To define critical cis-acting elements that regulate this enhancer, a series of deletions from the 5' and 3' ends of the Bgl II fragment were generated. Their effect on enhancer activity was assessed in IL-4-producing mast cell lines in transient transfection assays. Two functionally independent subregions, E1 and E2, were defined in this analysis. Both are required for full enhancer activity. Sequences identical to previously defined DNA-binding sites for SP1 and GATA are present within E1, and an ets binding site is located within E2. Although mutation of the SP1 sites had no effect on enhancer function, alteration of either the GATA or ets site reduced enhancer activity by 50-60%. Proteins that associate with the IL-4 intronic GATA and ets sites were detected in mast cell nuclear extracts by mobility-shift assays. Specific antibodies identified these factors as GATA-1 and GATA-2 and the ets family member PU.1. GATA-1, GATA-2, and PU.1 exhibit cell-specific expression, suggesting that these proteins play a critical role in the lineage-restricted activity of the IL-4 intronic enhancer in mast cells.
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PMID:PU.1 and GATA: components of a mast cell-specific interleukin 4 intronic enhancer. 805 53

Although GATA-binding transcription factors (GATA-1 and GATA-2) are strongly expressed in cultured mast cells (CMCs), their expression in mast cells within tissues has not been reported. We examined the expression of GATA-1 and GATA-2 in skin tissues of mice using Northern blot analysis and in situ hybridization. mRNA for GATA-2 but not for GATA-1 was expressed in skin mast cells of WB-+/+ embryos between days 15 and 17 postcoitum (pc). The expression was downregulated on and after day 18 pc. Skin mast cells did not express GATA-2 after birth either. When the number of skin mast cells was compared with the number of GATA-2 mRNA-expressing cells, GATA-2 mRNA appeared to be expressed by mast cells only when the number was increasing. When the mRNA expression of high-affinity IgE receptor beta-subunit and mast cell carboxypeptidase A was used as differentiation markers, the expression of these mRNAs continued even after the downregulation of GATA-2 expression. To clarify the relationship of the proliferation and GATA-2 expression, proliferating CMCs derived from WBB6F1-+/+ mice were transplanted into the peritoneal cavity of mast cell-deficient WBB6F1-W/Wv mice. The CMCs stopped both the proliferation and GATA-2 expression after the transplantation, suggesting the association of these two parameters in mast cells within tissues of mice.
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PMID:Abundant expression of transcription factor GATA-2 in proliferating but not in differentiated mast cells in tissues of mice: demonstration by in situ hybridization. 856 71

Phenotype of P815 mouse mast cells changes markedly during culture in the peritoneal cavity of syngenic BDF1 mice. The cells, cultured for 1 week in the peritoneal cavity of syngenic BDF1 mice, proliferate and express high levels of L-histidine decarboxylase (HDC) and mouse mast cell protease (MMCP)-6 mRNAs, indicating the ability of P815 cells to differentiate toward mature connective tissue mast cells. Peritoneal fluid aspirated from P815-inoculated BDF1 mouse and added to cultured P815 cells in vitro was also found to induce HDC mRNA expression, suggesting that at least some of the humoral factors in the peritoneal fluid induce HDC mRNA transcription. Among the erythroid transcription factors, P815 cells expressed GATA-2 but not GATA-1 mRNA before and after the intraperitoneal incubation. In contrast, the expression of NF-E2 subunit p45 disappeared, while expression of subunit mafK was markedly reduced after incubation. Cotransfection assays using HDC-luciferase reporter and p45 and/or mafK expression constructs showed that NF-E2 affects the transactivation of HDC gene. These results suggest that NF-E2 is also an important transcription factor in mast cell differentiation.
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PMID:Histidine decarboxylase expression in mouse mast cell line P815 is induced by mouse peritoneal cavity incubation. 891 Apr 69

PU.1 and GATA transcription factors appear to antagonize each other's function in the development of distinct lineages of the hematopoietic system. In contrast, we demonstrate that PU.1, like GATA-2, is essential for the generation of mast cells. PU.1-/- hematopoietic progenitors can be propagated in IL-3 and differentiate into mast cells or macrophages upon restoration of PU.1 activity. Using these progenitors and a conditionally activatable PU.1 protein, we show that PU.1 can negatively regulate expression of the GATA-2 gene. In the absence of GATA-2, PU.1 promotes macrophage but not mast cell differentiation. Reexpression of GATA-2 in such progenitors enables the generation of mast cells. We propose a developmental model in which cooperative function or antagonistic crossregulation by PU.1 of GATA-2 promotes distinct myeloid cell fates.
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PMID:Cooperative and antagonistic interplay between PU.1 and GATA-2 in the specification of myeloid cell fates. 1243 72

Transcription factor GATA-2 is a member of GATA family which binds a common DNA sequence motif [T/A (GATA) A/G] through an evolutionarily conserved zinc finger domain. An essential role for GATA-2 in the development of hematopoietic cells has recently been shown in gene knockout experiments in mice. GATA-2 gene disruption makes reduction in all hematopoietic precursors, whereas enforced expression of GATA-2 blocks normal hematopoiesis. GATA-2 exerts regulation in early embryo and cooperates with other GATA transcription factors in proliferation and differentiation of myeloid, erythroid, megakaryocytic and mast cell lineages. GATA-2 mRNA and protein could be detected in human myelogenous leukemia cell lines and in most patients with primary leukemias. Some data revealed that GATA-2 could transactivate the Cas-Br-E and graffi retroviruses, which can induce myelogenous leukemia in mice. However, the role of GATA-2 in pathogenesis of leukemia is still not well understood.
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PMID:The Role of Transcription Factor GATA-2 in Early Hematopoiesis. 1257 22


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