JAK2 MEDIATED SIGNAL TRANSDUCTION

JAK2 介导的信号转导

• 批准号: 6173911
• 负责人: NICHOLAS A CARPINO
• 金额: $ 3.75万
• 依托单位: ST. JUDE CHILDREN'S RESEARCH HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-10 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6173911
• 关键词: JAK kinase; Retroviridae; biological signal transduction; complementary DNA; cytokine; enzyme activity; enzyme structure; enzyme substrate; gene expression; genetically modified animals; hematopoiesis; hematopoietic stem cells; immunocytochemistry; in situ hybridization; laboratory mouse; molecular site; mutant; northern blottings; phosphorylation; polymerase chain reaction; protein protein interaction; protein sequence; tissue /cell culture; transcription factor; transfection /expression vector

The long term objectives of this research proposal are to characterize the signaling pathways downstream of the tyrosine kinase Jak2 which are critical for hematopoietic cell development. That Jak2 plays a critical role in hematopoiesis is demonstrated by the complete absence of several myeloid lineages in mice lacking a functional JAK2 gene. Furthermore, its importance in hematological development is underscored by the recent discovery that leukemic cells of several patients with different hematological malignancies contain an abnormal fusion protein comprised of the transcription factor TEL fused to the catalytic domain of JAK2. Although the signaling cascades activated by Jak2 are not well characterized, recent data suggests that tyrosine autophosphorylation of Jak2 is functionally important. One critical goal of this proposal is to analyze the autophosphorylation sites of JAK2. This will be accomplished, in part, by reconstituting Jak2-/- fetal liver cells with either wild-type or tyrosine-to-phenylalanine point mutants of Jak2, and functionally analyzing the cells by in vitro colony formation or in vivo reconstitution ability. Another important goal will be to identify and characterize molecules which interact directly with phosphorylated Jak2. Such molecules are good candidate Jak2 effector molecules. Thus, this study approaches the problem of studying Jak2 signaling on two fronts: firstly by analyzing Jak2 itself, and secondly, by analyzing the molecules which interact with Jak2.

这项研究计划的长期目标是表征酪氨酸激酶Jak 2下游的信号通路，这对造血细胞发育至关重要。在缺乏功能性JAK 2基因的小鼠中，几种骨髓谱系的完全缺失证明了JAK 2在造血中起着关键作用。此外，其在血液学发展中的重要性被最近的发现所强调，即患有不同血液学恶性肿瘤的几个患者的白血病细胞含有异常融合蛋白，所述异常融合蛋白由融合到JAK 2的催化结构域的转录因子TEL组成。 虽然信号级联激活的Jak 2没有得到很好的表征，最近的数据表明，酪氨酸自磷酸化的Jak 2是功能上的重要。 该提案的一个关键目标是分析JAK 2的自磷酸化位点。这将部分地通过用野生型或酪氨酸-苯丙氨酸突变体Jak 2重建Jak 2-/-胎肝细胞，并通过体外集落形成或体内重建能力功能分析细胞来实现。另一个重要的目标是鉴定和表征与磷酸化Jak 2直接相互作用的分子。这样的分子是良好的候选Jak 2效应分子。因此，本研究从两个方面研究Jak 2信号传导的问题：首先分析Jak 2本身，其次分析与Jak 2相互作用的分子。