Deciphering Wnt-Ror signaling in cytoskeletal regulation and tissue shape control

解读细胞骨架调节和组织形状控制中的 Wnt-Ror 信号传导

• 批准号: 9749980
• 负责人: Hsin-Yi Henry Ho
• 金额: $ 39.25万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9749980
• 关键词: Adhesions; Biochemical; Biological; Biological Assay; Biology; CRISPR/Cas technology; Caenorhabditis elegans; Cells; Congenital Abnormality; Congenital Disorders; Cytoskeleton; Development; Disease; Equipment and supply inventories; Family; Genetic; Genetic Screening; Genetic Transcription; Human; Kinesin; Knowledge; Link; Measurement; Mediating; Microscopy; Microtubules; Molecular; Morphogenesis; Motor; Mus; Neoplasm Metastasis; Organ; Pathologic; Pathway interactions; Play; Portraits; Process; Protein Biochemistry; Proteomics; Receptor Activation; Regulation; Reporter; Research; Robinow syndrome; Role; Shapes; Signal Pathway; Signal Transduction; Stereotyping; System; Time; Tissues; Ubiquitin; Work; base; cell behavior; cell motility; combat; comparative; embryo tissue; human disease; in vivo; insight; loss of function; member; multicatalytic endopeptidase complex; new therapeutic target; novel; novel marker; novel strategies; programs; signal processing

A long-standing question in biology concerns how tissues and organs acquire their stereotyped shape during development. The Wnt5a-Ror signaling pathway is a master regulator of embryonic tissue morphogenesis, and deregulation of the pathway has been found to cause a broad range of human pathological conditions, including the congenital disorders Robinow syndrome and Brachydactyly Type B, as well as cancer metastasis. In contrast to most well characterized developmental signaling pathways that function via gene transcription, the Wnt5a-Ror pathway functions through cytoskeletal regulation to control key morphogenetic cell behaviors, such as cell migration, polarization and adhesion. However, the molecular mechanisms that underlie Wnt5a- Ror function remain enigmatic. Our research program aims to fill three major gaps in the field: (1) What are the biochemical interactions that mediate Wnt5a-Ror signal processing and propagation within cells? (2) How does Wnt5a-Ror signaling engage the cytoskeleton to control morphogenetic cell behaviors? (3) How do these Wnt5a/Ror-driven processes ultimately control tissue morphogenesis in vivo? To this end, we have integrated mouse genetics and comparative proteomics to construct the first extended inventory of Wnt5a-Ror pathway components. This work not only provided crucial insights into the molecular mechanism of Wnt5a-Ror signal transduction, but also identified Kif26b (a member of the kinesin microtubule motor family) as a critical cytoskeletal effector of the pathway. Through gain- and loss-of-function studies, we demonstrated that Kif26b mediates the ability of the Wnt5a-Ror pathway to control cell migration, and that this function of Kif26b is conserved from C. elegans to humans. Mechanistically, we have established the key finding that Wnt5a-Ror signaling controls the cellular steady-state concentration of Kif26b via a mechanism involving the ubiquitin- proteasome system. Using this novel Wnt5a-Ror-Kif26b signaling paradigm, we have successfully developed a reporter assay that for the first time, allows for quantitative measurement of Wnt5a-Ror signaling activity in live cells. In this application, we propose to use a combination of protein biochemistry, microscopy and genetics to elucidate the molecular mechanism linking Ror receptor activation to Kif26b degradation, the cell biological mechanism underlying Kif26b regulation of cytoskeletal dynamics and cell migration, and the in vivo role of the Wnt5a-Ror-Kif26b signaling cassette in embryonic tissue morphogenesis. Moreover, we will pair our Wnt5a- Ror signaling reporter with large-scale CRISPR/Cas9-based genetic screens to identify additional constituents of the pathway. The successful completion of the project will (1) provide the first detailed molecular portrait of the Wnt5a-Ror signaling network, (2) reveal the cell biological mechanisms by which Wnt5a-Ror signaling regulates cytoskeletal dynamics and tissue morphogenesis, and (3) suggest novel biomarkers and therapeutic targets for Wnt5a-Ror driven diseases.

生物学中一个长期存在的问题是，组织和器官是如何在生理过程中获得它们的定型形状的