Cytomechanics: The Mechanical Basis of Cell Form and Structure

ISBN-13: 9783642728655 / Angielski / Miękka / 2012 / 294 str.

J. Rgen Bereiter-Hahn; O. Roger Anderson; Wolf-Ernst Reif

Opis

Genetic information determines the composition of molecules comprising cytoskeletal elements, membranes and receptors. The supramolecular arrangement of these components represents a self-assembly process controlled by physicochemical and mechanical interactions. This general hypothesis demarcates the aim of studying cellular mechanics. Description and evaluation of mechanical properties of cells and their organelles, as well as of the forces exerted by them, is the scope of this book on Cytomechanics. Emphasis is laid on the role of mechanical properties in the generation of shape and cytoplasmic motion, and on the basic principles and components determining mechanical properties.

Spis treści

I. General Principles.- I.1 Mechanical Principles of Architecture of Eukaryotic Cells.- 1.1 Introduction.- 1.2 Basic Mechanical Parameters of Cells.- 1.3 Cellular Viscosity.- 1.4 Elasticity, Contractile Forces, and Surface Tension.- 1.5 The Structural Basis of Cell Mechanics.- 1.5.1 Actin and Actin-Based Structures.- 1.5.2 Membrane-Associated Actin Fibrils.- 1.5.3 Microtubules and Related Structures.- 1.5.4 Intermediate Filaments and Related Structures.- 1.6 Aspects of Cytoplasmic Architecture.- 1.6.1 Localization of Organelles.- 1.6.2 Interaction of Cytoskeletal Elements in Generating Cell Shape.- 1.6.3 Cytoplasmic Streaming.- 1.7 Physiological Effects of Mechanical Stresses.- 1.7.1 Mechanical Aspects of Morphogenesis During Embryo Development.- 1.7.2 Influences of Mechanical Stresses on Cellular Metabolism.- References.- I.2 Evaluation of Cytomechanical Properties.- 2.1 Introduction.- 2.2 Physical Structure of the Cell.- 2.3 Mechanical Properties of the Cell Surface.- 2.3.1 Relationship Between the Surface Force and the Internal Pressure of the Cell.- 2.3.2 Direct Measurement of the Internal Pressure.- 2.3.3 Indirect Measurements of the Surface Force and the Internal Pressure.- 2.3.3.1 Compression Method.- 2.3.3.2 Suction Method.- 2.3.3.3 Stretching Method.- 2.3.3.4 Sessile Drop Method.- 2.3.4 Elasticity and Viscoelasticity of the Cell Surface.- 2.4 Mechanical Properties of the Endoplasm.- 2.4.1 Measurements of Mechanical Properties of the Endoplasm.- 2.4.1.1 Centrifuge Method.- 2.4.1.2 Magnetic Particle Method.- 2.4.1.3 Capillary Method.- 2.4.1.4 Brownian Movement Method.- 2.4.1.5 Diffusion Method.- 2.4.2 Relationship Between the Mechanical Properties and Submicroscopic Structure of the Endoplasm.- References.- I.3 Use of Finite Element Methods in Cytomechanics: Study of the Mechanical Stability of the Skeletal Basal Plate of Callimitra a Biomineralizing Protozoan.- 3.1 Introduction.- 3.2 Callimitra Architecture.- 3.3 Finite Element Approach.- 3.4 Further Applications of FEM and Their Implications.- References.- I.4 Mechanics and Hydrodynamics of Rotating Filaments.- 4.1 The Molecular Basis of Filament Rotation.- 4.2 Longitudinal (Screw-Mechanical) Effects.- 4.2.1 Waving and Screwing.- 4.2.2 The Oscillation.- 4.2.3 Control of Polymerization and Depolymerization.- 4.2.4 The Translocation of Particles.- 4.2.5 Crossbridges.- 4.3 Lateral (Hydrodynamic) Effects.- 4.3.1 Pattern of Flows.- 4.3.2 Flows Adjacent to a Wall.- 4.3.3 Flows and Molding of an Adjacent Liquid Surface.- 4.3.4 Rolling Motions and Self-Arrangements.- References.- II. The Supramolecular Level.- II.1 Mechanical Concepts of Membrane Dynamics: Diffusion and Phase Separation in Two Dimensions.- 1.1 Introduction.- 1.2 Translational Diffusion in Fluid Phase Membranes.- 1.2.1 Net Transport by Diffusion: The Einstein-Smoluchowski Equation.- 1.2.2 Diffusion Modeled as a Stochastic Random Walk: The Free Volume Model.- 1.2.3 Diffusion Modeled by Continuum Hydromechanics: The Saffman-Delbrück Model.- 1.2.4 Diffusion in Biological Membranes.- 1.3 Fluid-Solid Phase Separation in Two Dimensions.- 1.3.1 Effective Medium and Percolation Theory.- 1.3.2 Phase Separation in Lipid Monolayers.- 1.3.3 Phase Separation in Biological Membranes.- 1.4 Concluding Comments.- References.- II.2 Implications of Microtubules in Cytomechanics: Static and Motile Aspects.- 2.1 Microtubule Structure: Statics and Elasticity.- 2.1.1 Substructure of Microtubules.- 2.1.2 Rigidity of Microtubules.- 2.1.3 Integration of Microtubules into the Cytoskeleton.- 2.2 Microtubule-Associated Dynamics: Motion and Tension.- 2.2.1 Elongation of Microtubules.- 2.2.2 Shortening of Microtubules.- 2.2.3 Treadmilling of Microtubules.- 2.2.4 Organelle Movement Along Microtubules.- 2.2.5 Gliding of Microtubules.- 2.2.6 Sliding of Microtubules.- 2.2.7 Movement of Axostyle Microtubules.- 2.2.8 Complex Interactions of Microtubules.- 2.2.9 Contraction of Microtubule Arrays.- 2.3 Conclusions.- References.- II.3 The Nature and Significance of ATP-Induced Contraction of Microtubule Gels.- 3.1 Introduction.- 3.2 Microtubule Gelation-Contraction.- 3.2.1 In Vitro Experiments.- 3.2.2 Significance of Microtubule Gelation-Contraction in Living Cells.- 3.2.2.1 Mitotic Spindle.- 3.2.2.2 Axonal Transport.- References.- II.4 Generation of Propulsive Forces by Cilia and Flagella.- 4.1 Introduction.- 4.2 Hydrodynamic Interactions.- 4.3 Passive Elastic Properties.- 4.4 Active Mechanical Properties.- 4.5 Conclusions.- References.- II.5 The Cortical Cytoplasmic Actin Gel.- 5.1 Historical Background.- 5.2 The Assembly of Actin and Actin-Binding Proteins Regulating Actin Assembly.- 5.3 The Rheology of Actin and Its Modulation by Actin-Binding Proteins and Other Factors.- 5.4 Actin Gelation in the Cell.- 5.5 Regulation of the Actin Sol/Gel Transformation in the Cell.- References.- II.6 Dynamic Organization and Force Production in Cytoplasmic Strands.- 6.1 Nature and Locomotory Phenomena of Physarum Plasmodia.- 6.2 The Generation of Hydrostatic Pressure Flow.- 6.3 Contractile Activities as Measured by Tensiometry.- 6.4 Analysis of Morphological Alterations Induced by Stretch Experiments.- 6.5 Nature and Implications of the Contraction Cycle.- 6.6 The Widely Unknown Regulation.- 6.7 Cytomechanical Implications.- References.- III. Mechanical Factors Determining Morphogenesis of Protists.- III.1 Determination of Body Shape in Protists by Cortical Structures.- 1.1 Introduction.- 1.2 Intracellular Cortex Structures.- 1.3 Extracellular Cortex Structures.- 1.4 Concluding Remarks.- References.- III.2 Morphogenetic Forces in Diatom Cell Wall Formation.- 2.1 Introduction.- 2.2 Possible Functions of the Diatom Cell Wall.- 2.3 Preconditions of Valve Formation.- 2.3.1 Mitosis and Cleavage.- 2.3.2 The Molding Surface: The Plasmalemma.- 2.3.3 The Mold for the Valve Outline.- 2.4 Valve Formation.- 2.4.1 The Silica Deposition Vesicle (SDV).- 2.4.2 The Role of the Nucleus, Microtubule Center, and Microtubules.- 2.4.3 The Molding System for the Valve Pattern.- 2.4.4 Mechanisms for Mechanical Stabilization of the Valve.- 2.4.5 The Organic Coat and Valve Release.- 2.5 Conclusions.- References.- III.3 The Cytoskeletal and Biomineralized Supportive Structures in Radiolaria.- 3.1 Introduction.- 3.2 Cytoskeletal Organization of the Axopodia.- 3.3 Biomineralization and Skeletal Morphogenesis.- 3.3.1 Analysis of Growth Phases.- 3.3.2 Finite Element Analysis.- 3.3.2.1 FEM Descriptors.- 3.3.2.2 FEM Results.- 3.3.2.3 Limitations and Implications of FEM Analysis with Radiolaria.- References.- IV. Mechanical Factors Determining Plant Cell Morphogenesis.- IV. 1 Mechanical and Hydraulic Aspects of Plant Cell Growth.- 1.1 Introduction.- 1.2 Directionality of Cell Growth.- 1.2.1 Patterns of Expansion.- 1.2.2 Wall Architecture.- 1.2.3 Multinet Growth.- 1.2.4 The Wall Matrix.- 1.3 Wall Loosening and Expansion.- 1.3.1 Physics of Wall Expansion.- 1.3.2 Stress Relaxation.- 1.3.3 Molecular Models of Wall Loosening.- 1.4 Water Uptake and Turgor Maintenance.- 1.4.1 Physics of Water Uptake.- 1.4.2 Restriction of Growth by Water Transport.- 1.4.3 Solute Uptake.- 1.5 Summary.- References.- IV.2 Plant Cytomechanics and Its Relationship to the Development of Form.- 2.1 Introduction.- 2.2 The Logic of Development.- 2.2.1 The Role of the Genome in the Development of Form.- 2.2.2 The Role of the Environment in the Development of Form.- 2.3 The Architecture of Plant Form.- 2.3.1 Division and Growth. The Basic Events.- 2.3.2 Growth as a Source of Mechanical Stress.- 2.3.3 Factors Affecting Stress Distribution in Embryonic Plant Organs.- 2.3.4 The Role of Stress in the Generation of Form.- 2.4 The Ultrastructural Basis of Cell Behavior.- 2.4.1 The Role of Cytomechanics in the Development of Form.- 2.5 Other Responses to Mechanical Stimuli. Reaction Wood.- 2.5.1 Tropic Responses.- 2.6 Meiosis as a Mechanically-Induced Process.- 2.6.1 The Sporangium as a Stress-Focusing Device.- 2.6.2 Isotropic Stress as a Developmental Effector.- References.- IV.3 Mechanical Properties of the Cyclamen Stalk and Their Structural Basis.- 3.1 Anatomy of the Cyclamen Persicum Flower Stalk.- 3.2 Internal Hydrostatic Pressure.- 3.3 Behavior Under Ultimate Load.- 3.4 Summary.- References.- V. Mechanical Forces Determining the Shape of Metazoan Cells.- V.I Forces Shaping an Erythrocyte.- 1.1 Introduction.- 1.2 Membrane Elasticity.- 1.2.1 Shear Elasticity.- 1.2.1.1 Molecular Basis of Shear Elasticity.- 1.2.1.2 Metabolic, pH, and Ionic Effects.- 1.2.2 Area Elasticity.- 1.2.2.1 Molecular Basis of Area Elasticity.- 1.2.3 Bending Elasticity.- 1.2.3.1 Molecular Basis of Bending Rigidity.- 1.3 Membrane Viscosity.- 1.3.1 Molecular Basis of Membrane Viscosity.- 1.4 Erythrocyte Shape.- References.- V.2 Hydrostatic Pressure in Metazoan Cells in Culture: Its Involvement in Locomotion and Shape Generation.- 2.1 Introduction.- 2.2 Osmotic Equations Applied to Cells.- 2.3 Physical State of Cell Water.- 2.4 Solute Leakage.- 2.5 Osmotic Behavior of Cytogel.- 2.6 Generation of Intracellular Hydrostatic Pressure.- 2.6.1 Osmotic Behavior of Cells in Culture.- 2.6.2 Determination of Hydrostatic Pressure in Culture Cells.- 2.6.3 “Visualization” of Tension in the Cortical Fibrillar-Meshwork-Plasma Membrane Complex.- 2.7 Functional Significance of Hydrostatic Pressure in Wall-Free Cells.- 2.7.1 Cell Shape.- 2.7.2 Cell Locomotion.- 2.7.3 Integration of Cells into Tissues.- 2.7.4 Hydraulic Interaction of Organelles.- References.- V.3 The Transmission of Forces Between Cells and Their Environment.- 3.1 Introduction.- 3.2 Focal Contact: Subcellular Level.- 3.3 Traction: Cellular Level.- 3.4 Adhesion: Supracellular Level.- 3.5 Conclusions.- References.