REGULATING MITF'S ACTIVATION OF OSTEOCLAST TARGET GENES

调节 MITF 破骨细胞靶基因的激活

• 批准号: 7132706
• 负责人: Kim Carpenter Mansky
• 金额: $ 14.68万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-15 至 2008-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7132706
• 关键词: osteoclasts; proteins

DESCRIPTION (provided by applicant): Microphthalmia-associated transcription factor (Mitf) and Tfe3 are basic helix-loop-helix leucine zipper transcription factors that are expressed in osteoclasts. We have demonstrated that Mitf and Tfe3 colloborate to activate genes important for osteoclast differentiation. Evidence that Mitf and Tfe3 are necessary for osteoclast differentiation is demonstrated by the fact that mice null for expression of Mitf and Tfe3 are osteopetrotic. Using a yeast two hybrid screen, we identified Cdc25C-associated kinase 1 (C-TAK1) and POH1, a component of the proteasome lid, as interacting with the amino terminus of Mitf. This proposal attempts to 1) determine how Mitf is translocated to the nucleus in osteoclasts and 2) to identify proteins that affect Mitfs stability in osteoclasts. To define the interaction between C-TAK1 and Mitf (aim 1), we will determine which amino acid residue of Mitf is phosphorylated by C-TAK1, determine which Mitf amino acid residues are critical for binding to 14-3-3 proteins and determine what effect C-TAK1 and 14-3-3 interaction has on Mitfs cellular location. 14-3-3 are a family of proteins that recognize specific phosphorylated serines and bind to and sequester a protein in the cytoplasm. To determine the effect of Mitf and POH1's interaction (aim 2), we will determine if Mitf's stability is affected by CSF-1 and RANKL signaling, map the region of Mitf that interacts with POH1 and determine the effect of POH1's interaction with Mitf on Mitfs activation of osteoclast target genes. By understanding how Mitf activates ostoeclast specific genes, drug targets may be suggested that will lead to therapies to control the differentiation and activation of osteoclasts.

描述（由申请人提供）：小眼症相关转录因子（Mitf）和Tfe 3是在破骨细胞中表达的碱性螺旋-环-螺旋亮氨酸拉链转录因子。我们已经证明，Mitf和Tfe 3共同激活破骨细胞分化的重要基因。Mitf和Tfe 3是破骨细胞分化所必需的证据由以下事实证明，即Mitf和Tfe 3表达缺失的小鼠是骨硬化性的。使用酵母双杂交筛选，我们确定Cdc 25 C相关激酶1（C-TAK 1）和POH 1，蛋白酶体盖的一个组成部分，作为与Mitf的氨基末端相互作用。该建议试图1）确定Mitf如何在破骨细胞中移位到细胞核和2）鉴定影响Mitf在破骨细胞中稳定性的蛋白质。为了确定C-TAK 1和Mitf之间的相互作用（目的1），我们将确定Mitf的哪个氨基酸残基被C-TAK 1磷酸化，确定哪些Mitf氨基酸残基对于结合14-3-3蛋白至关重要，并确定C-TAK 1和14-3-3相互作用对Mitf细胞定位的影响。14-3-3是识别特异性磷酸化丝氨酸并结合并隔离细胞质中的蛋白质的蛋白质家族。为了确定Mitf和POH 1相互作用的影响（目的2），我们将确定Mitf的稳定性是否受到CSF-1和RANKL信号传导的影响，绘制Mitf与POH 1相互作用的区域，并确定POH 1与Mitf相互作用对Mitf激活破骨细胞靶基因的影响。通过了解Mitf如何激活破骨细胞特异性基因，可以提出药物靶点，这将导致控制破骨细胞分化和激活的治疗。