5.6 Interaction Between Protein and Lipid . . . . . . . . . . . . . . . . . . . . . 76
5.6.1
Peripheral Enzyme and Integral Enzyme . . . . . . . . . . . . . 76
5.6.2
Synthesis of Membrane Protein and Signal Peptide . . . . . 77
5.6.3
Study of Interaction in Membrane Model System . . . . . . . 78
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
6 Physical Properties of Biomembranes and Cellular Functions . . . . . . 81
6.1 Diffusion Controlled Process by Fluidity of Biomembranes . . . . . . 81
6.2 Phase Separation of Biomembranes and Biological Functions
of Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
6.3 Micro Domain of Biomembranes (Lipid Raft) . . . . . . . . . . . . . . . . 83
6.4 Conversion of Membrane Lipid with Receiving Stimulus
and Functions of a Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
6.5 Non-bilayer Forming Lipids and Function of Biomembrane . . . . . . 87
6.5.1
Membrane Structure Formed by Non-bilayer Forming
Lipids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
6.5.2
Non-bilayer Membrane Structure in Membrane Fusion . . . 88
6.5.3
Regulation of Biomembrane Formation by Non-bilayer
Structure as Lipid Storeroom in Biomembrane Lipid . . . . 90
6.5.4
Changes of Structure and Physical Property
and Biological Function in Biomembranes . . . . . . . . . . . . 90
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
7 Moving Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
7.1
Biological Movements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
7.1.1
Muscle Contraction and Mechano-Enzyme . . . . . . . . . . 96
7.1.2
Muscle Contraction at the Molecular Level . . . . . . . . . . 99
7.1.3
Single-Molecule Measurement for the Motor Function
of Myosin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
7.2
Cellular Movements Other Than Muscle Contraction . . . . . . . . . 102
7.2.1
Three Filament Systems Supporting the Dynamism
in the Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
7.2.2
Non-muscle Myosins and Organelle Transport . . . . . . . . 103
7.3
Actin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
7.3.1
Actin Monomer Structure . . . . . . . . . . . . . . . . . . . . . . . 106
7.3.2
Actin Filament Structure . . . . . . . . . . . . . . . . . . . . . . . . 107
7.3.3
Actin Polymerization and Depolymerization . . . . . . . . . 109
7.4
Kinetics of Actin Polymerization . . . . . . . . . . . . . . . . . . . . . . . . 113
7.5
Treadmill Phenomenon: Actin Polymerization Under
the Non-equilibrium Condition . . . . . . . . . . . . . . . . . . . . . . . . . 114
7.6
Microtubule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
7.6.1
Structure of Microtubule . . . . . . . . . . . . . . . . . . . . . . . . 116
7.6.2
Microtubule Polymerization and Depolymerization . . . . . 117
Contents
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