Axonal membrane proteins are transported in distinct carriers: a two-color video microscopy study in cultured hippocampal neurons

Christoph Kaether, Paul Skehel, Carlos G Dotti

Research output: Contribution to journalArticlepeer-review

Abstract

Neurons transport newly synthesized membrane proteins along axons by microtubule-mediated fast axonal transport. Membrane proteins destined for different axonal subdomains are thought to be transported in different transport carriers. To analyze this differential transport in living neurons, we tagged the amyloid precursor protein (APP) and synaptophysin (p38) with green fluorescent protein (GFP) variants. The resulting fusion proteins, APP-yellow fluorescent protein (YFP), p38-enhanced GFP, and p38-enhanced cyan fluorescent protein, were expressed in hippocampal neurons, and the cells were imaged by video microscopy. APP-YFP was transported in elongated tubules that moved extremely fast (on average 4.5 micrometer/s) and over long distances. In contrast, p38-enhanced GFP-transporting structures were more vesicular and moved four times slower (0.9 micrometer/s) and over shorter distances only. Two-color video microscopy showed that the two proteins were sorted to different carriers that moved with different characteristics along axons of doubly transfected neurons. Antisense treatment using oligonucleotides against the kinesin heavy chain slowed down the long, continuous movement of APP-YFP tubules and increased frequency of directional changes. These results demonstrate for the first time directly the sorting and transport of two axonal membrane proteins into different carriers. Moreover, the extremely fast-moving tubules represent a previously unidentified type of axonal carrier.
Original languageEnglish
Pages (from-to)1213-24
Number of pages12
JournalMolecular Biology of the Cell
Volume11
Issue number4
DOIs
Publication statusPublished - Apr 2000

Keywords

  • Amyloid beta-Protein Precursor
  • Animals
  • Axonal Transport
  • Bacterial Proteins
  • Cells, Cultured
  • Fluorescent Antibody Technique
  • Green Fluorescent Proteins
  • Hippocampus
  • Kinesin
  • Luminescent Proteins
  • Membrane Proteins
  • Microscopy, Video
  • Microtubules
  • Neurons
  • Oligonucleotides, Antisense
  • Rats
  • Recombinant Fusion Proteins
  • Synaptophysin

Fingerprint Dive into the research topics of 'Axonal membrane proteins are transported in distinct carriers: a two-color video microscopy study in cultured hippocampal neurons'. Together they form a unique fingerprint.

Cite this