权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Positive and negative regulation of the cytokinesis contractility controller

胞质分裂收缩性控制器的正向和负向调节

基本信息

批准号：
9769504
负责人：
Priyanka Kothari
金额：
$ 2.74万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-07-02 至 2020-02-07
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9769504
关键词：
Actins Acute Affect Affinity Behavior Binding Biochemical Biochemical Pathway Biological Process Biology Cardiac Myosins Cell Shape Cell division Cell physiology Cells Chemicals Complex Contractile Proteins Crosslinker Cytokinesis Cytoskeletal Proteins Data Development Developmental Process Dictyostelium Dimerization Disease Dominant-Negative Mutation Embryonic Development Environment Enzymes Excision Feedback Filament Fluorescence Genetic Goals Hepatocyte Human Biology Image Immunoprecipitation In Vitro Interphase Light Lung Malignant neoplasm of pancreas Mass Spectrum Analysis Measures Mechanics Mediating Mitotic spindle Modeling Molecular Morphogenesis Myoblasts Myosin ATPase Myosin Type II Neoplasm Metastasis Oxidoreductase Post-Translational Protein Processing Process Production Proteins Regulation Resolution Role Scaffolding Protein Shapes Signal Pathway Signal Transduction Signaling Protein Site Spectrum Analysis Stress Structure System Testing Tissues Work biophysical analysis cancer cell cell motility cortexillin I crosslink daughter cell genetic regulatory protein genetic selection human disease in vivo insight loss of function mechanical behavior mechanical force methylmalonate mutant non-muscle myosin overexpression propionyl-coenzyme A recruit response scaffold sensor single molecule

项目摘要

PROJECT SUMMARY Every biological process, ranging from cell migration to embryogenesis and tissue morphogenesis, relies on a cell’s ability to adapt to changing mechanical environments. While we understand many biochemical signaling pathways involved, the mechanisms that are integrated to govern a cell’s response to mechanical forces remain a mystery. Deciphering these interactions will shed light on the mechanical changes that drive both normal and disease state processes. To reveal how the cell responds to various forces, the Robinson lab studies Dictyostelium cytokinesis, a model shape change process by which one cell divides to form two daughter cells. The lab has discovered that cytokinesis is driven by an integrated control system composed of proteins that modulate their behavior in response to both mechanical and biochemical signals. Although we know many of the players involved in the cytokinetic control system, their biochemical interactions that allow force propagation through the cortical network are still unknown. My goal is to characterize the regulatory mechanisms that characterize these interactions, which will be critical to elucidate the mechanisms of a cell’s response to its mechanical environment. To identify the direct interactions that govern a cell’s mechanical response, we performed immunoprecipitation followed by mass spectrometry on two key nodes of the cytokinetic control system, the scaffolding protein IQGAP2 and the actin crosslinker cortexillin I. This approach led to the discovery of potential binding partners of these nodes. Using a combination of Fluorescence Cross- Correlation Spectroscopy (FCCS) and Single Molecule Pulldown (SiMPull), we have discovered a potential mechanism of inhibition by a negative regulator of the system, IQGAP1. To further understand how IQGAP1 mediates inhibition, I will purify key cytoskeletal proteins and use quantitative biochemical approaches to measure binding affinities and implement a chemically-inducible dimerization system to assess the inhibitory activity of IQGAP1. In addition, I will use super-resolution imaging during both interphase and cytokinesis to characterize alterations in complexes formed by these key cytoskeletal proteins that allow force transduction through the network. Moreover, I will determine the cellular role of methylmalonate semialdehyde dehydrogenase (mmsdh), which catalyzes the production of propionyl-coA. Mmsdh was identified as an interactor of cortexillin I, but was also previously identified in a genetic selection in our lab. It is possible that proteins may modified by propionylation, an underappreciated post-translational modification, which may facilitate positive regulation of the cytokinetic control system. Through a combination of genetics, mass spectrometry, and biophysical analyses, I will elucidate the cellular function of mmsdh. The work proposed here will decipher the molecular mechanisms of positive and negative regulation of the contractile network. This information will be critical for understanding the cell’s ability to sense and respond to mechanical forces, yielding insight into both normal developmental processes, as well as disease state progression.

项目总结