Real-time imaging of axonal transport of quantum dot-labeled BDNF in primary neurons

J Vis Exp. 2014 Sep 15:(91):51899. doi: 10.3791/51899.

Abstract

BDNF plays an important role in several facets of neuronal survival, differentiation, and function. Structural and functional deficits in axons are increasingly viewed as an early feature of neurodegenerative diseases, including Alzheimer's disease (AD) and Huntington's disease (HD). As yet unclear is the mechanism(s) by which axonal injury is induced. We reported the development of a novel technique to produce biologically active, monobiotinylated BDNF (mBtBDNF) that can be used to trace axonal transport of BDNF. Quantum dot-labeled BDNF (QD-BDNF) was produced by conjugating quantum dot 655 to mBtBDNF. A microfluidic device was used to isolate axons from neuron cell bodies. Addition of QD-BDNF to the axonal compartment allowed live imaging of BDNF transport in axons. We demonstrated that QD-BDNF moved essentially exclusively retrogradely, with very few pauses, at a moving velocity of around 1.06 μm/sec. This system can be used to investigate mechanisms of disrupted axonal function in AD or HD, as well as other degenerative disorders.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Video-Audio Media

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Axonal Transport / physiology*
  • Brain-Derived Neurotrophic Factor / analysis*
  • Brain-Derived Neurotrophic Factor / metabolism
  • Computer Systems
  • HEK293 Cells
  • Hippocampus / cytology
  • Hippocampus / physiology
  • Humans
  • Image Processing, Computer-Assisted
  • Microfluidic Analytical Techniques
  • Molecular Sequence Data
  • Neurons / physiology*
  • Quantum Dots / analysis*
  • Quantum Dots / metabolism
  • Rats

Substances

  • Brain-Derived Neurotrophic Factor
  • BDNF protein, human