Neurochemical Research

, Volume 38, Issue 12, pp 2535–2541 | Cite as

Localization of Mitochondrial Carnitine/Acylcarnitine Translocase in Sensory Neurons from Rat Dorsal Root Ganglia

  • Annamaria TonazziEmail author
  • Cristina Mantovani
  • Matilde Colella
  • Giorgio Terenghi
  • Cesare Indiveri
Original Paper


The carnitine/acylcarnitine transporter is a transport system whose function is essential for the mitochondrial β-oxidation of fatty acids. Here, the presence of carnitine/acylcarnitine carrier (CACT) in nervous tissue and its sub-cellular localization in dorsal root ganglia (DRG) neurons have been investigated. Western blot analysis using a polyclonal anti-CACT antibody produced in our laboratory revealed the presence of CACT in all the nervous tissue extracts analyzed. Confocal microscopy experiments performed on fixed and permeabilized DRG neurons co-stained with the anti-CACT antibody and the mitochondrial marker MitoTracker Red clearly showed a mitochondrial localization for the carnitine/acylcarnitine transporter. The transport activity of CACT from DRG extracts reconstituted into liposomes was about 50 % in respect to liver extracts. The experimental data here reported represent the first direct evidence of the expression of the carnitine/acylcarnitine transporter in sensory neurons, thus supporting the existence of the β-oxidation pathway in these cells.


Sensory neurons DRG Mitochondria Carnitine/acylcarnitine transporter Immunohistochemistry β-Oxidation 



This work was partially supported by founds from Programma Operativo Nazionale 01_00937-MIUR.

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

Supplementary movie 1  Three-dimensional reconstruction of the mitochondrial network close to the cell body of the same sensory neuron depicted in Supplementary Figure 1 (ROI). Z-stack confocal images were 3D-projected with the Fiji plugin “3D viewer”. Video shows 360° view of image reconstruction. (MPG 3,188 kb)

11064_2013_1168_MOESM2_ESM.tif (7.2 mb)
Supplementary figure 1  Maximum-intensity projections of confocal laser scanning image stacks of a DRG preparation. (A) CACT labeled with a polyclonal antibody and visualized with an Alexa Fluor 488 conjugated anti-rabbit antibody, (B) mitochondria stained with MitoTracker Red CMXRos, (C) nuclear counterstaining with Hoechst 33,258, (D) overlay of the three images. Scale bar = 25 μm. The region of interest (ROI) depicted in panel D was subjected to three-dimensional image reconstruction with the Fiji plugin “3D viewer” [43] (see also the Supplementary Movie 1). (TIFF 7,355 kb)


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Annamaria Tonazzi
    • 1
    • 2
    Email author
  • Cristina Mantovani
    • 3
    • 4
  • Matilde Colella
    • 2
  • Giorgio Terenghi
    • 3
  • Cesare Indiveri
    • 5
  1. 1.CNR Institute of Biomembranes and BioenergeticsBariItaly
  2. 2.Department of Biosciences, Biotechnology and BiopharmaceuticsUniversity of Bari “Aldo Moro”BariItaly
  3. 3.Blond McIndoe Research Laboratory, Regenerative BiomedicineUniversity of ManchesterManchesterUK
  4. 4.Department of Pharmacological and Biomolecular SciencesUniversity of MilanMilanItaly
  5. 5.Unit of Biochemistry and Molecular Biotechnology, Department of BEST (Biologia, Ecologia e Scienze della Terra)University of CalabriaArcavacata di RendeItaly

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