Myosin drives retrograde F-actin flow in neuronal growth cones

Neuron. 1996 Apr;16(4):769-82. doi: 10.1016/s0896-6273(00)80097-5.


Actin filaments assembled at the leading edge of neuronal growth cones are centripetally transported via retrograde F-actin flow, a process fundamental to growth cone guidance and other forms of directed cell motility. Here we investigated the role of myosins in retrograde flow, using two distinct modes of myosin inhibition: microinjection of NEM inactivated myosin S1 fragments, or treatment with 2,3-butanedione-2-monoxime, and inhibitor of myosin ATPase. Both treatments resulted in dose-dependent attenuation of retrograde F-actin flow and growth of filopodia. Growth was cytochalasin sensitive and directly proportional to the degree of myosin inhibition, suggesting that retrograde flow results from superimposition of two independent processes: actin assembly and myosin-based filament retraction. These results provide the first direct evidence for myosin involvement in neuronal growth cone function.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Actins / metabolism*
  • Animals
  • Axonal Transport
  • Biological Transport
  • Chickens
  • Cytoskeleton / drug effects
  • Cytoskeleton / ultrastructure
  • Diacetyl / analogs & derivatives
  • Diacetyl / pharmacology
  • Enzyme Inhibitors / pharmacology
  • Ethylmaleimide / pharmacology
  • Microinjections
  • Muscle, Skeletal / chemistry
  • Myosin Subfragments / pharmacology
  • Myosins / antagonists & inhibitors
  • Myosins / physiology*
  • Neurons / metabolism*
  • Neurons / ultrastructure*


  • Actins
  • Enzyme Inhibitors
  • Myosin Subfragments
  • diacetylmonoxime
  • Myosins
  • Diacetyl
  • Ethylmaleimide