Cell and Tissue Research

, Volume 365, Issue 1, pp 13–27 | Cite as

Super-resolution structured illumination fluorescence microscopy of the lateral wall of the cochlea: the Connexin26/30 proteins are separately expressed in man

  • Wei Liu
  • Fredrik Edin
  • Hans Blom
  • Peetra Magnusson
  • Annelies Schrott-Fischer
  • Rudolf GlueckertEmail author
  • Peter A. Santi
  • Hao Li
  • Göran Laurell
  • Helge Rask-AndersenEmail author
Regular Article


Globally 360 million people have disabling hearing loss and, of these, 32 million are children. Human hearing relies on 15,000 hair cells that transduce mechanical vibrations to electrical signals in the auditory nerve. The process is powered by the endo-cochlear potential, which is produced by a vascularized epithelium that actively transports ions in conjunction with a gap junction (GJ) system. This “battery” is located “off-site” in the lateral wall of the cochlea. The GJ syncytium contains the GJ protein genes beta 2 (GJB2/connexin26 (Cx26)) and 6 (GJB6/connexin30 (Cx30)), which are commonly involved in hereditary deafness. Because the molecular arrangement of these proteins is obscure, we analyze GJ protein expression (Cx26/30) in human cochleae by using super-resolution structured illumination microscopy. At this resolution, the Cx26 and Cx30 proteins were visible as separate plaques, rather than being co-localized in heterotypic channels, as previously suggested. The Cx26 and Cx30 proteins thus seem not to be co-expressed but to form closely associated assemblies of GJ plaques. These results could assist in the development of strategies to treat genetic hearing loss in the future.


Human cochlea Connexin (as elsewhere) 26/30 Structured illumination microscopy 







Gap junction


Tight junction


Transmission electron microscopy


Endocochlear potential


Maximal intensity projection


Super-resolution structured illumination microscopy




GJ protein gene beta 2


GJ protein gene beta 6


Stria vascularis


Gene encoding a member of the inward rectifier-type K+ channel family Kir4.1


Gene encoding the furosemide-sensitive Na+/K+/2Cl- membrane co-transporter


Gene encoding the voltage-gated potassium channel Kv7.1 (KvLQT1)



Supplementary material

441_2016_2359_MOESM1_ESM.pptx (72 kb)
ESM 1 Image and data precision were evaluated by means of an EMCCD camera and SIM focus from ZEN calibration on 40-nm beads. A lateral precision of approximately 80 nm and 250 nm axially was obtained. (PPTX 72.4 kb)
441_2016_2359_MOESM2_ESM.wmv (7.8 mb)
ESM 2 3-D video recording of the SR-SIMZ-stacks of Cx26 and Cx30 protein expression in the lateral cochlear wall demonstrating the separate expression. (WMV 7.80 mb)
441_2016_2359_MOESM3_ESM.pptx (2 mb)
ESM 3 Confocal IHC show basal cells identified by their expression of Claudin (green), a TJ protein expressed selectively in the basal cells and type I fibrocytes. These TJs help to maintain the particular electrochemical environment of the intrastrial space. Marginal and intermediate cells express Na+−K+−ATPase (red). (PPTX 2.01 mb)


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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Wei Liu
    • 1
  • Fredrik Edin
    • 1
  • Hans Blom
    • 2
  • Peetra Magnusson
    • 3
  • Annelies Schrott-Fischer
    • 4
  • Rudolf Glueckert
    • 4
    Email author
  • Peter A. Santi
    • 5
  • Hao Li
    • 1
  • Göran Laurell
    • 1
  • Helge Rask-Andersen
    • 1
    Email author
  1. 1.Department of Surgical Sciences, Head and Neck Surgery, Section of Otolaryngology, Department of OtolaryngologyUppsala University HospitalUppsalaSweden
  2. 2.Science for Life laboratory, Department of Applied PhysicsRoyal Institute of TechnologySolnaSweden
  3. 3.Department of Immunology, Genetics and PathologyClinical ImmunologyUppsalaSweden
  4. 4.Department of OtolaryngologyMedical University of InnsbruckInnsbruckAustria
  5. 5.Department of OtolaryngologyUniversity of MinnesotaMinneapolisUSA

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