Motor Types Motor Track Functions Myosin F-actin Cell crawling Myosin‖ F-acti Muscle contraction Cell division Phagocytosis Kinesin microtubule Organelle transport Mitosis meiosis Dynein microtubule Flagella cilia Polymerases ds and ssdnA Replication, Repair Helicases Recombination
Motor Types Motor Track Functions Myosin F-actin Cell crawling Myosin II F-actin Muscle contraction Cell division Phagocytosis Kinesin microtubule Organelle transport Mitosis & meiosis Dynein microtubule Flagella & cilia Polymerases, ds and ssDNA Replication, Repair Helicases Recombination 11
Muscle Anatomy Collection of myofibers Z disk Z disk Myosin thick filament Myofiber(single cell) 1000000 Nucleus Plasma membra M lin Myofibril Sarcomere I-band band -band- Sarcomere z disk A band Muscle Types Skeletal: fast Cardiac: fast Smooth slow
Muscle Anatomy Muscle Types: Skeletal: fast Cardiac: fast Smooth: slow 12
Myosin Heads Walk Along Actin Filaments Actin(free) 080068 Myosin (tethered to surface)
Sliding filament assay Myosin Heads Walk Along Actin Filaments
Polar Biopolymer Molecules The Tracks Motor Proteins Walk along Myosin walks along Actin G-Actin(globular) F-Actin(microfilaments) end Image removed due to copyright considerations See [Lodish 4th ed ] Figure 18-2 +end Diameter 6-8nm Persistence length 16m Young s modulus 1.3-2.5X109Pa
Polar Biopolymer Molecules : The Tracks Motor Proteins Walk Along Myosin walks along Actin G-Actin (globular) F-Actin (microfilaments) - end Image removed due to copyright considerations. See [Lodish 4th ed.] Figure 18-2. + end Diameter: 6-8 nm Persistence length: 16 µm Young’s modulus: 1.3-2.5 x 109 Pa 14
Myosin: the actin motor protein All myosins have head, neck, and tail domains with distinct functions Image removed due to copyright considerations See [Lodish 4th ed. Figure 18-20 Viewable online at the pubMed bookshelf http://www.ncbi.nlm.nihgovlentrez/query.fcgi?db=books Figure 18-20
Myosin: the actin motor protein All myosins have head, neck, and tail domains with distinct functions Image removed due to copyright considerations. See [Lodish 4th ed.] Figure 18-20. Viewable online at the PubMed Bookshelf: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=Books 15 Figure 18-20