Quiz 4 (ch 37 intracellular movement) current topics of cell bio.txt

  1. studying intracellular motility for slow transport mechanisms
    • Radiolabeling: Insert radioactive labeled aa, and watch movement of labeled protein
    • Photobleaching: Insert fluorescent labeled tubulin, then uniformly fluoresce axon, photobleach zone and zone remains stationary
    • Fluorescent Microscopy: Labeled neurofilaments, can observe them through a bleached zone
  2. cytoplasmic streaming and intracellular localization
    • in plants: dependent on actin cytoskeleton
    • acellular slime mold: cytoplasmic streaming driven by cortical actomyosin contractions
  3. Budding yeast
    transport of vesicles along actin filament cables from mother to bud
  4. Passive vs active mechanism
    • passive: molecules/structures less than 50nm. Mostly individual molecules & complexes, ie ribosomes
    • Active: molecules/structures/ORGANELLES Greater than 50nm. All organelles, many RNAs, viruses. Depend on microtubulues/microfilaments for movement
  5. MicroTUBULE motors activities
    • antero fast axonal 1-2um/s
    • retro fast axonal
    • Chromosome movement
    • SLOW axonal
  6. Microtubule polymerization activity
    ER Elongation 0.1um/s
  7. MicroFILAMENT motors activities
    • Cytoplasmic streaming (Nitella) 60um/s
    • Cytoplasmic streaming (Physarum-slime mold) 500um/s
  8. MicroFILAMENT polymerization activity
    Actin-propelled comet (Listeria) 0.5um/s
  9. DIC mycroscopy
    allows for analysis of unstained living material
  10. Glial cell and RNA
    mRNA granules move through branches to disperse, driven by kinesins and dyneins
  11. General methods of studying Intracellular motility
    • Modern microscopy methods: DIC, fluorescence, confocal
    • Video recording
    • Attaching fluorescent molecules to purified proteins
    • bleaching or photoactivating fluorescent tags
    • Chimeric gene creation for in vivo synthesis of tagged proteins/organelles
    • Developed genetic model systems
Card Set
Quiz 4 (ch 37 intracellular movement) current topics of cell bio.txt
intracellular movement