Probing structural and biophysical mechanisms of mitochondrial membrane ultrastructure

探究线粒体膜超微结构的结构和生物物理机制

• 批准号: 10809205
• 负责人: Luke H. Chao
• 金额: $ 1.43万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-15 至 2026-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10809205
• 关键词: Apoptosis; Autosomal Dominant Optic Atrophy; Beds; Biophysical Process; Calcium Signaling; Cardiac; Cardiac health; Cell physiology; Cells; Complex; Computer Analysis; Crista ampullaris; Cryo-electron tomography; Cryoelectron Microscopy; Dependence; Disease; Elements; Encephalopathies; Environment; Family; Foundations; Goals; Heart Mitochondria; Heterogeneity; Homeostasis; In Vitro; Inner mitochondrial membrane; Knowledge; Leigh Disease; Lipids; Liposomes; Liver diseases; Malignant Neoplasms; Membrane; Membrane Proteins; Metabolic; Metabolism; Mitochondria; Modeling; Molecular Conformation; Morphology; Mutate; Nature; Nerve Degeneration; OPA1 gene; Organelles; Physiological; Physiology; Play; Production; Property; Protein Conformation; Proteins; Regulation; Resolution; Role; Shapes; Structure; System; Testing; Tissues; Visualization; biophysical techniques; computational pipelines; early onset; interest; member; membrane reconstitution; mitochondrial membrane; nervous system disorder; particle; programs; protein complex; protein protein interaction; protein structure; reconstitution; solute; targeted treatment; therapeutic development; tool

PROJECT SUMMARY/ABSTRACT Organelle morphology is specialized for the highly adapted functions found in complex tissues. Mitochondrial ultrastructure is exquisitely tuned to metabolic and physiological state. Abnormal morphology is a hallmark of neurological disorders, cardiac conditions and cancer. With the cryo-EM `resolution revolution', we have developed dramatic new understanding of membrane protein structure and regulation, but our knowledge of organelle structure lags behind. This is due to the pleomorphic nature of organelles, and the challenge of assigning specific morphological features to protein states. The overarching goals of my lab are to understand, at a mechanistic level, how protein conformational change is influenced by subcellular context, how membrane ultrastructure is regulated by protein factors, and the functional interplay of these elements in physiology and disease. Over the next five years, my group will develop a technical platform that combines electron cryo- microscopy (cryo-EM) and biophysical methods to study mitochondrial ultrastructure and its regulation. We will apply our recent developed in vitro reconstitution systems to visualize reconstituted membrane proteins in liposomes and bilayers by single-particle cryo-EM. We will mature our newly established electron cryo- tomography (cryo-ET) pipeline for computational analyses of membrane properties to understand their dependence on protein-protein interactions. We shall develop new structural and biophysical methods to characterize organelle lipid heterogeneity. And finally, we will explore assembly or protein complexes in native contexts. Together these approaches will advance mechanistic understanding of protein conformational state and help us identify the fundamental determinants of organelle shape. We are broadly interested in questions of membrane spacing, composition and curvature. We will develop tools precisely tailored for these questions using mitochondria as a test bed, exploring the structure and function of candidate factors that regulate mitochondrial membrane morphology, which play causal roles in neurodegenerative conditions. Opa1 is the inner-membrane fusogen and cristae remodeler mutated in Dominant Optic Atrophy. SLC25A46 is an outer- membrane member of the solute transporter family that plays important roles in coordinating lipid homeostasis in Leigh Syndrome. MICOS is the stabilizer and regulator of cristae junctions (the `choke-point' to the mitochondrial inner-membrane folds) whose loss results in early-onset fatal mitochondrial encephalopathy with liver disease. This project's immediate impacts include sharing new models to understand mitochondrial shape with cell biologists, equipping pharmacologists with new, highly specific conformational targets for therapeutic development, and providing physiologists with fundamental rules for understanding tissue specialization. The long-term goal is to build an extensible approach generalizable to other organelles, and a foundation for rational control of organelle morphology from first principles.

项目总结/文摘

项目成果

In situ architecture of Opa1-dependent mitochondrial cristae remodeling.

Opa1 依赖性线粒体嵴重塑的原位结构。

• DOI: 10.1101/2023.01.16.524176
• 发表时间: 2023
• 期刊: bioRxiv : the preprint server for biology
• 作者: Fry,MichelleY;Navarro,PaulaP;Hakim,Pusparanee;Ananda,VirlyY;Qin,Xingping;Landoni,JuanC;Rath,Sneha;Inde,Zintis;Lugo,CamilaMakhlouta;Luce,BridgetE;Ge,Yifan;McDonald,JulieL;Ali,Ilzat;Ha,LeillaniL;Kleinstiver,BenjaminP;C
• 通讯作者: C

Absence of Cardiolipin From the Outer Leaflet of a Mitochondrial Inner Membrane Mimic Restricts Opa1-Mediated Fusion.

• DOI: 10.3389/fmolb.2021.769135
• 发表时间: 2021
• 期刊: Frontiers in molecular biosciences
• 影响因子: 5
• 作者: Ge Y;Boopathy S;Nguyen TH;Lugo CM;Chao LH
• 通讯作者: Chao LH