Regulation and feedback in Fat/Dachsous signaling

Fat/Dachsous 信号传导的调节和反馈

• 批准号: 10716713
• 负责人: SETH S BLAIR
• 金额: $ 30.94万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-25 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10716713
• 关键词: Adaptor Signaling Protein; Address; Affect; Affinity; Animals; Back; Binding; Binding Proteins; Binding Sites; Biochemistry; C-terminal; Caseins; Cells; Data; Defect; Development; Drosophila Proteins; Drosophila genus; Drosophila melanogaster; Epithelial Cells; Epithelium; F Box Domain; Face; Fatty acid glycerol esters; Feedback; Fetal Development; GOLGA7 gene; Goals; Growth; Homologous Gene; Human; Human Genetics; Human Pathology; In Vitro; Instruction; Investigation; Link; Mediating; Mediator; Membrane; Modeling; Modification; Molecular Genetics; Mutation; Myosin ATPase; Neurologic; Palmitic Acylation Site; Pathology; Pathway interactions; Phosphorylation; Phosphorylation Site; Phosphotransferases; Proliferating; Proteins; Regulation; Role; Route; SH3 Domains; Scaffolding Protein; Signal Pathway; Signal Transduction; Structure; Surface; Syndrome; System; Tail; Tertiary Protein Structure; Testing; Tissues; Ubiquitination; Van Maldergem syndrome; casein kinase; cell behavior; cell type; cofactor; cost effective; in vivo; intercellular communication; mutant; nervous system disorder; novel; palmitoylation; planar cell polarity; polarized cell; scaffold; tool; transmission process; ubiquitin ligase; ubiquitin-protein ligase

The giant Drosophila protocadherins Fat and Dachsous (Ds) form a heterophilic, bidirectional signaling pair that regulates proliferation via the growth-inhibiting Hippo pathway, and planar cell polarity (PCP) both through and independently of the “core” PCP pathway. These functions are shared by their mammalian homologs, and human mutations in Fat and Ds homologs cause the neurological and multisystem defects of Hennekam and Van Maldergem syndromes. Despite its importance, only a little is known about how binding between Fat and Ds change cell behavior, and thus how it regulates development and pathology. Fat, Ds and the effectors of the Hippo and PCP pathways are concentrated in the subapical domain of epithelial cells, and the intracellular domain (ICD) of Fat has strong effects on the subapical levels of two critical proteins. The first is the scaffolding myosin Dachs, which binds and inhibits Warts (Lats1/2), the final effector kinase in the Hippo pathway, and which regulates Sple in the core PCP pathway. The second is the FERM scaffolding protein Expanded, which stimulates Warts activity. Using a combination of protein-binding screens, biochemistry and molecular genetics, we established a link from the Fat ICD to Dachs and Expanded levels and localization via the DHHC palmitoyltransferase Approximated and one of its targets, the SH3 domain protein Dlish. However, Approximated must have additional targets in the pathway, and the details of Approximated and Dlish regulation are poorly understood. In this proposal we outline plans to identify characterize new Approximated targets, including Expanded itself, and further plans to analyze the regulation of Approximated activity and target recognition, first through modification of Approximated and its targets, and second through the previously uncharacterized GOLGA7-like adapter protein CG5447. Fat and Ds are also remarkable in their ability to polarize cells along the epithelial plane via their own cell-by- cell polarization to opposite cell faces. We have initiated studies on the intracellular control and amplification of Fat/Ds polarization. We explore previously unsuspected roles for intracellular pathway components in the regulation of Fat and Ds levels and polarization, including the casein kinse 1 Dco, the ubiquitin ligase Slimb, the myosin Dachs, and the intracellular domain of Fat itself.

巨大的果蝇原钙粘蛋白 Fat 和 Dachsous (Ds) 形成异嗜性双向信号对 通过生长抑制 Hippo 途径和平面细胞极性 (PCP) 调节增殖 并且独立于“核心”PCP 途径。这些功能是其哺乳动物同源物所共有的，并且 Fat 和 Ds 同源物的人类突变导致 Hennekam 和 Ds 的神经系统和多系统缺陷 范马尔德赫姆综合征。尽管它很重要，但人们对脂肪和脂肪之间的结合方式知之甚少。 Ds 改变细胞行为，从而改变其调节发育和病理的方式。 Fat、Ds 以及 Hippo 和 PCP 途径的效应子集中在 上皮细胞和脂肪的细胞内结构域（ICD）对两种细胞的根尖下水平有强烈影响 关键蛋白质。第一个是支架肌球蛋白 Dachs，它结合并抑制疣 (Lats1/2)，最后一个是 Hippo 通路中的效应激酶，在核心 PCP 通路中调节 Sple。第二个是 FERM 支架蛋白 Expanded，可刺激疣活动。 通过结合蛋白质结合筛选、生物化学和分子遗传学，我们建立了一种联系 从 Fat ICD 到 Dachs，并通过 DHHC 棕榈酰转移酶扩展水平和定位 近似的目标之一是 SH3 结构域蛋白 Dlish。然而，近似必须有 该途径中的其他目标，以及 Approximim 和 Dlish 监管的细节知之甚少。 在本提案中，我们概述了确定新近似目标特征的计划，包括扩展本身， 并进一步计划分析近似活动和目标识别的调节，首先通过 修改 Approximated 及其目标，然后通过之前未表征的 GOLGA7 类 接头蛋白CG5447。 Fat 和 Ds 还具有显着的能力，即通过它们自己的逐个细胞沿上皮平面极化细胞。 细胞极化到相对的细胞面。我们已经启动了细胞内控制和扩增的研究 脂肪/Ds 极化。我们探索了细胞内通路成分在以前未曾怀疑过的作用 调节脂肪和 Ds 水平和极化，包括酪蛋白激酶 1 Dco、泛素连接酶 Slimb、 肌球蛋白 Dachs 和脂肪本身的细胞内结构域。