Hedgehog Signal Transduction Across the Cell Membrane

跨细胞膜的刺猬信号转导

• 批准号: 7168011
• 负责人: LAWRENCE LUM
• 金额: $ 29.35万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-01 至 2011-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7168011
• 关键词: Basal cell carcinoma; Biological Assay; Cell membrane; Cells; Classification; Complex; Cultured Cells; Cytoplasmic Protein; Cytoplasmic Tail; Deformity; Detection; Development; Diagnosis; Disease; Disease Progression; Double-Stranded RNA; Drosophila genome; Drosophila genus; Erinaceidae; Face; Genes; Goals; Heparan Sulfate Proteoglycan; Immunoglobulins; Integral Membrane Protein; Intracellular Membranes; Libraries; Malignant Neoplasms; Malignant neoplasm of pancreas; Malignant neoplasm of prostate; Maps; Measures; Mediating; Membrane; Modeling; Mus; Numbers; Pathway interactions; Phosphorylation; Post Translational Modification Analysis; Prevention; Process; Prosencephalon; Protein Family; Proteins; RNA library; Reagent; Recruitment Activity; Regulation; Signal Pathway; Signal Transduction; Technology; Testing; Therapeutic Intervention; base; cell growth; extracellular; gain of function; gene function; hedgehog signal transduction; human SMO protein; insight; member; mouse genome; novel; protein protein interaction; receptor; receptor function; response; tool; transcription factor; transmission process

DESCRIPTION (provided by applicant): The Hedgehog (Hh) family of proteins coordinates cellular growth and differentiation in a number of developmental contexts by eliciting graded responses in the cells surrounding Hh-producing cells. Aberrant Hh pathway activity is associated with developmental deformities of the face and forebrain, and prevalent cancers such as prostate cancer and basal cell carcinoma (BCC). Understanding how the Hh signal is conveyed from the extracellular milieu to intracellular effectors is therefore pivotal to the successful prevention, detection, and treatment of these and other diseases associated with Hh signaling. This proposal focuses on the mechanisms that allow cellular recognition of the secreted Hh protein at the plasma membrane and subsequent transduction of a signal across the membrane to induce specific intracellular responses. Direct interaction of Hh with the twelve transmembrane protein Patched (Ptc) is required for relinquishing Ptc-mediated suppression of the seven transmembrane protein Smoothened (Smo) in target cells. This interaction is facilitated by Dally-like protein (Dlp), a heparan sulfate proteoglycan, and CG9211, a member of the immunoglobulin (Ig) superfamily of receptors. Activated Smo transduces a signal across the membrane in a process that involves recruiting to its cytoplasmic tail a large regulatory complex that includes the transcription factor Cubitus interruptus (Ci). The mechanisms by which Dlp, CG9211, and these cytoplasmic protein-protein interactions contribute to Hh pathway response are unclear. In order to study reception and transmission of the Hh signal at the cell membrane, we have developed novel tools that include cultured cell-based assays for pathway responsiveness, reagents for isolating and detecting Hh signaling complexes, and double-stranded RNA libraries that inhibit specific gene function in Drosophila and mouse by RNA-mediated interference (RNAi). By incorporating these tools in a biochemically- and genetically-based strategy, we propose to: 1) determine how Hh signal is sensed at the cell membrane, 2) determine how Smo transduces the Hh signal to cytoplasmic components, and 3) identify Hh pathway components by systematically testing gene function using RNAi-based technology.

描述（由申请人提供）：刺猬（HH）蛋白质家族在许多发育环境中通过引起产生HH产生细胞周围细胞的分级反应来协调细胞的生长和分化。异常的HH途径活性与面部和前脑的发育畸形有关，并且普遍存在的癌症（如前列腺癌和基底细胞癌（BCC））。因此，了解如何将HH信号从细胞外环境传达到细胞内效应子是对这些与HH信号相关的这些疾病的成功预防，检测和治疗的关键。该建议的重点是允许质膜上分泌的HH蛋白识别细胞识别的机制，并随后在整个膜上转导信号以诱导特定的细胞内反应。 HH与十二个跨膜蛋白（PTC）的直接相互作用是为了放弃对靶细胞中七种跨膜蛋白平滑（SMO）的PTC介导的抑制所必需的。这种相互作用是由硫酸乙酰肝素蛋白聚糖的Dally样蛋白（DLP）和受体超家族超家族的成员CG9211促进的。激活的SMO在一个过程中涉及募集到其细胞质尾部的过程中，将信号转导了整个膜的信号，其中包括转录因子Cubitus Interruptus（CI）。 DLP，CG9211和这些细胞质蛋白 - 蛋白质相互作用的机制尚不清楚。为了研究细胞膜上HH信号的接收和传播，我们开发了新的工具，其中包括基于培养的细胞响应能力的基于细胞的测定，用于隔离和检测HH信号传导复合物的试剂以及通过RNA介导的drosophila和小鼠抑制特定基因功能的双链RNA库，并通过RNA介导的Interference（RNAi）抑制特定的基因功能（RNAI）。通过将这些工具纳入生化和遗传的策略中，我们提出：1）确定在细胞膜处如何感测HH信号，2）确定SMO如何通过基于RNAI的技术来确定HH信号将HH信号转导HH信号到细胞质成分中，并确定HH途径成分。