Biomedical Engineering Reference
In-Depth Information
4
Molecular
Motors
Timothy D. Riehlman, Zachary T. Olmsted, and Janet L. Paluh
CONTENTS
4.1. Introduction........................................................................................................................... 73
4.2. Molecular.Motors:.“Life.Is.Motion”................................................................................... 74
4.2.1. Molecular.Motors.of.the.Cellular.Cytoskeleton................................................... 76
4.2.2. Myosins:.Actin-Dependent.Motors........................................................................ 76
4.2.3. Microtubule.Workhorses:.Conventional.Kinesin.and.Klps............................... 78
4.2.4. Force.Generation.and.Processivity.of.Myosins,.Kinesin,.and.Klps.................. 79
4.2.5. Motor.Folding.as.a.Means.of.Regulation.............................................................. 86
4.2.6. Dynein:.A.Multiprotein.Microtubule.Motor........................................................ 89
4.2.7. Non-Tracking.Cellular.Molecular.Motors............................................................. 89
4.2.8. Chemical.Motors....................................................................................................... 90
4.3. Cellular.Cytoskeleton.......................................................................................................... 91
4.3.1. A.Restless.Architecture........................................................................................... 91
4.3.2. Actin.Microilaments............................................................................................... 92
4.3.3. Microtubules............................................................................................................. 93
4.4. Application.of.Molecular.Motors.in.Nanotechnology.................................................... 93
4.4.1. Ingenuity.through.Dynamics.in.Nanodevices.................................................... 93
4.4.2. Reverse.Engineering.Nature................................................................................... 94
4.4.3. Molecular.Motors.in.Transport.Designs............................................................... 95
4.4.4. Directional.Guidance............................................................................................... 96
4.4.5. Tracks......................................................................................................................... 98
4.4.6. Cargo.Attachment.and.Release.............................................................................. 99
4.4.7. Designer.Motor.Proteins....................................................................................... 101
4.4.8. Controlling.Motion................................................................................................ 102
4.5. Conclusions.and.Perspectives.......................................................................................... 102
References..................................................................................................................................... 103
4.1 Introduction
The.remarkably.dynamic.and.complex.manufacturing.environment.of.the.eukaryotic.cell.
is. currently. unrivaled. by. man-made. systems. (Mann,. 2008).. Perhaps. most. recognized. in.
its. assemblage. of. cellular. machinery. are. devices. to. control. signaling. from. the. environ-
ment,. regulate. cytoplasmic. to. nuclear. import. through. specialized. nuclear. pores,. direct.
the. unwinding,. replication,. and. repair. of. deoxyribonucleic. acid. (DNA),. drive. selective.
genomic. expression. through. epigenetic,. transcriptional,. and. translational. machineries,.
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