neuroscience 4 part 2

  1. Actin filaments
    -made up of actin
  2. actin filaments
    actin monomer
  3. Microtubuli
    • -Hollow cylinder, not used as pipe, but track for ex. motor protein to "walk" on
    • -made up of tubuli heterodimers alpha tubuli + beta tubulin
    • -end+ beta tubulin exposed
    • -end - alpha tubulin exposed
  4. Actin filaments
    • -made up of actin monomers
    • -two strands (two strings of pearls), twisted around each other
    • -more flexible than microtubuli
    • -can be crosslinked by other proteins
  5. Intermediate filaments
    • rope-like structure
    • eight tetramers twisted into a ropelike filament
  6. Intermediate filaments
    • -provide mechanical strength, for ex in axons in neurons
    • -individual monomer is a long polypeptide
    • -pair up in dimers
    • -two dimers in a tetramer
    • -tetramers are lined up in a "rope"
  7. Neurofilaments
    • -a type of intermediate filament
    • -high conc in axons
    • -controls diameter of axon
    • .diameter varies between different types of axons
    • .diameter determine speed of electrical signal
  8. ALS
    amyotrpic lateral sclerosis, aka
  9. Lon Geling's disease
    • -accummulation +abnormal assembly of -neurofilaments in motor neurons
    • -motor neurons die
    • -cause -effect unknown
  10. MAPs
    -Microtubuli associated proeins
  11. Hippocaupus
    • neuron from hippocauspus (memory)
    • tau-green, in axon
  12. Map2
    orange, in cellbody+dendrites
  13. Alzheimers disease
    • -aggregates of tau
    • -called neurofibrillary tangles
  14. Tau and Map
    • Tau in axons
    • Map2 in cell body +dendrites
    • -determine how tightly packed microtubuli are
    • -stabalize microtubuli aganist disassembly
    • -tau is shorter-microtubuli more tightly packed
  15. Anterograde transport
    -cellbody to axon terminal
  16. kinesin
    motor protein, anterograde transport
  17. retrograde transport
    • -axon terminal to cell body
    • -motor protein :dynein
    • -no protein synthesis at axon terminal
    • -organelles (mitochordia) synaptic vesicles must be transported there.
  18. Kinesin
    • -made of two heavy chain (heads) + coiled tail-attached to cargo
    • -speed 1 meter in 2-3 days
    • -energy demands 1 ATP/step
  19. List 7 steps of kinesin
    • -leading head contain adp in active site
    • -head binds to microtubli-ADP is exhanged for ATP
    • -necklinker changes conformation
    • -lagging head is thrown forward +binds to microtubuli
    • -first head (now trailing) hydrolyses ATP to ADP + pi
    • .released to microtubuli
    • -leading head exchange ADP for ATP
    • -necklinker changes conformation lagging head thros forward then repeat
Card Set
neuroscience 4 part 2
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