RasGRP4-dependent Responses in Mast Cells

肥大细胞中 RasGRP4 依赖性反应

• 批准号: 7554623
• 负责人: Richard L Stevens
• 金额: $ 39.3万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-02-15 至 2011-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7554623
• 关键词: 1,2-diacylglycerol; Acetates; Affinity; Asthma; Basophils; Binding; Bone Marrow; Boxing; C3H/HeJ Mouse; Carboxypeptidase; Cations; Cell Line; Cell Nucleus; Cells; Chromosomes; Complement; Complex; Cytokine Receptors; Cytoplasmic Granules; Cytosol; Data; Deacetylase; Development; Diacylglycerol Kinase; Diglycerides; Disease; Dissociation; Eicosanoids; Event; Exhibits; Expressed Sequence Tags; Extravasation; Figs - dietary; Functional disorder; Genes; Genetic Transcription; Genetic Variation; Guanine Nucleotide Exchange Factors; Guanine Nucleotides; Guanosine Diphosphate; Guanosine Triphosphate; Hematopoietic; Human; Hypersensitivity; IgE; IgE Receptors; Immune; Immunoglobulins; Immunology; Infection; Inflammatory; Interleukins; KITLG gene; Knowledge; Lead; Leukotrienes; Mass Spectrum Analysis; Mediating; Mediator of activation protein; Molecular; Mononuclear; Mus; Neurofibromatosis Type 1 Protein; Pathway interactions; Peptide Hydrolases; Pharmacologic Substance; Play; Post-Transcriptional Regulation; Printing; Prostaglandin D2; Prostaglandins; Protein Family; Protein Isoforms; Proteinase-Activated Receptors; Proteins; RNA; RNA Splicing; Rattus; Receptor Protein-Tyrosine Kinases; Reperfusion Injury; Reverse Transcriptase Polymerase Chain Reaction; Rheumatoid Arthritis; Role; Signal Pathway; Signal Transduction; Signaling Pathway Gene; Signaling Protein; Single Nucleotide Polymorphism; Site; Small Interfering RNA; Stem Cell Factor; Testing; Tissues; Vascular Endothelial Growth Factors; airway hyperresponsiveness; base; cell type; cytokine; embryonic stem cell; in vivo; leukemia; macrophage; mast cell; member; methacholine; microbial; mouse RasGRP4 protein; neurofibroma; neutrophil; phorbol ester receptor; phorbol-12-myristate; progenitor; progesterone 11-hemisuccinate-(2-iodohistamine); prostaglandin R2 D-isomerase; ras Proteins; response; sulfotransferase; transcription factor

DESCRIPTION (provided by applicant): We recently cloned the cDNAs and genes that encode the fourth member of the Ras Guanine Nucleotide Releasing Protein (RasGRP) family of signaling proteins. RasGRP4 is a mast cell (MC) restricted, cation-dependent, guanine nucleotide exchange factor. It also is a diacylglycerol/phorbol ester receptor that plays a prominent role in dictating which protease, cytokine, and eicosanoid mediators are expressed in MC lines. Allelic variants of RasGRP4 have been identified, as well as functionally different isoforms of RasGRP4 that are the result of differential splicing of its gene. Earlier gene-linkage studies of C3H/HeJ mice revealed a prominent site on chromosome 7A3-B1 that controls its intrinsic airway reactivity to methacholine. We recently found that the MCs developed from this hyporesponsive mouse produce a defective isoform of mRasGRP4. The accumulated data suggest that RasGRP4 is of critical importance in MC development and that the expression of abnormal isoforms of RasGRP4 can lead to MC dysfunction. Complementary approaches will be used in the proposed studies to test these hypotheses and to expand our knowledge concerning the recently identified RasGRP family of signaling proteins. In Specific Aim 1, the transcriptional and posttranscriptional mechanisms that regulate the expression of mouse and human RasGRP4 will be identified. In Specific Aim 2, the functional importance of allelic isoforms of RasGRP4 and its different domains will be evaluated. The predominant genes and signaling pathways in MCs that are regulated by RasGRP4 also will be identified, as well as the control mechanisms that dampen RasGRP4- dependent signaling events in MCs. In Specific Aim 3, RasGRP4-deficient, non transformed MCs will be created to evaluate the importance of this signaling protein in MC development and function in vivo. Because RasGRP4 is a MC-restricted signaling protein that appears to act downstream of the tyrosine kinase receptor Kit, it is anticipated that the obtained data will significantly advance our knowledge concerning the poorly defined Kit-dependent pathway that dominantly controls MC development and function. It also is anticipated that targeted disruption of RasGRP4 expression and/or activity in humans using pharmaceutical and other approaches will be beneficial in MC-dependent disorders.

描述（由申请人提供）：我们最近克隆了编码信号蛋白Ras鸟嘌呤核苷酸释放蛋白（RasGRP）家族第四个成员的cDNA和基因。 RasGRP4 是一种肥大细胞 (MC) 限制的、阳离子依赖性的鸟嘌呤核苷酸交换因子。它也是一种二酰甘油/佛波酯受体，在决定 MC 系中表达哪些蛋白酶、细胞因子和类二十烷酸介质方面发挥着重要作用。已鉴定出 RasGRP4 的等位基因变体，以及功能不同的 RasGRP4 亚型，这是其基因差异剪接的结果。早期对 C3H/HeJ 小鼠的基因连锁研究揭示了 7A3-B1 染色体上的一个显着位点，该位点控制着其内在气道对乙酰甲胆碱的反应性。我们最近发现，从这种反应低下的小鼠中发育而来的 MC 产生了有缺陷的 mRasGRP4 亚型。积累的数据表明 RasGRP4 在 MC 发育中至关重要，RasGRP4 异常异构体的表达可导致 MC 功能障碍。在拟议的研究中将使用补充方法来检验这些假设并扩展我们对最近发现的 RasGRP 信号蛋白家族的了解。在具体目标 1 中，将确定调节小鼠和人类 RasGRP4 表达的转录和转录后机制。在具体目标 2 中，将评估 RasGRP4 等位基因亚型及其不同结构域的功能重要性。还将确定 MC 中受 RasGRP4 调节的主要基因和信号传导途径，以及抑制 MC 中 RasGRP4 依赖性信号传导事件的控制机制。在具体目标 3 中，将创建 RasGRP4 缺陷型、未转化的 MC，以评估该信号蛋白在 MC 发育和体内功能中的重要性。 由于 RasGRP4 是一种 MC 限制性信号蛋白，似乎在酪氨酸激酶受体 Kit 的下游起作用，因此预计获得的数据将显着增进我们对主要控制 MC 发育和功能的定义不明确的 Kit 依赖性途径的认识。预计使用药物和其他方法靶向破坏人类 RasGRP4 表达和/或活性将有益于 MC 依赖性疾病。

项目成果

Ancient origin of mast cells.

• DOI: 10.1016/j.bbrc.2014.07.124
• 发表时间: 2014-08-22
• 期刊: BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
• 影响因子: 3.1
• 作者: Wong, G. William;Zhuo, Lisheng;Kimata, Koji;Lam, Bing K.;Satoh, Nori;Stevens, Richard L.
• 通讯作者: Stevens, Richard L.