Article | Published:

A hierarchy of ankyrin-spectrin complexes clusters sodium channels at nodes of Ranvier

Nature Neuroscience volume 17, pages 16641672 (2014) | Download Citation

Abstract

The scaffolding protein ankyrin-G is required for Na+ channel clustering at axon initial segments. It is also considered essential for Na+ channel clustering at nodes of Ranvier to facilitate fast and efficient action potential propagation. However, notwithstanding these widely accepted roles, we show here that ankyrin-G is dispensable for nodal Na+ channel clustering in vivo. Unexpectedly, in the absence of ankyrin-G, erythrocyte ankyrin (ankyrin-R) and its binding partner βI spectrin substitute for and rescue nodal Na+ channel clustering. In addition, channel clustering is also rescued after loss of nodal βIV spectrin by βI spectrin and ankyrin-R. In mice lacking both ankyrin-G and ankyrin-R, Na+ channels fail to cluster at nodes. Thus, ankyrin R–βI spectrin protein complexes function as secondary reserve Na+ channel clustering machinery, and two independent ankyrin-spectrin protein complexes exist in myelinated axons to cluster Na+ channels at nodes of Ranvier.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    et al. Ion channel clustering at the axon initial segment and node of ranvier evolved sequentially in early chordates. PLoS Genet. 4, e1000317 (2008).

  2. 2.

    et al. Three mechanisms assemble central nervous system nodes of Ranvier. Neuron 78, 469–482 (2013).

  3. 3.

    et al. Glial and neuronal isoforms of Neurofascin have distinct roles in the assembly of nodes of Ranvier in the central nervous system. J. Cell Biol. 181, 1169–1177 (2008).

  4. 4.

    et al. A glial signal consisting of gliomedin and NrCAM clusters axonal Na+ channels during the formation of nodes of Ranvier. Neuron 65, 490–502 (2010).

  5. 5.

    , , , & Nodes of Ranvier act as barriers to restrict invasion of flanking paranodal domains in myelinated axons. Neuron 69, 244–257 (2011).

  6. 6.

    , & AnkyrinG. A new ankyrin gene with neural-specific isoforms localized at the axonal initial segment and node of Ranvier. J. Biol. Chem. 270, 2352–2359 (1995).

  7. 7.

    & Spectrin and ankyrin-based pathways: metazoan inventions for integrating cells into tissues. Physiol. Rev. 81, 1353–1392 (2001).

  8. 8.

    , , & βIV spectrin is recruited to axon initial segments and nodes of Ranvier by ankyrinG. J. Cell Biol. 176, 509–519 (2007).

  9. 9.

    et al. An ankyrinG-binding motif is necessary and sufficient for targeting Nav1.6 Na+ channels to axon initial segments and nodes of Ranvier. J. Neurosci. 32, 7232–7243 (2012).

  10. 10.

    et al. Nodes of Ranvier and axon initial segments are ankyrin G-dependent domains that assemble by distinct mechanisms. J. Cell Biol. 177, 857–870 (2007).

  11. 11.

    et al. AnkyrinG is required for clustering of voltage-gated Na channels at axon initial segments and for normal action potential firing. J. Cell Biol. 143, 1295–1304 (1998).

  12. 12.

    et al. A common ankyrin-G-based mechanism retains KCNQ and NaV channels at electrically active domains of the axon. J. Neurosci. 26, 2599–2613 (2006).

  13. 13.

    et al. Neurofascin assembles a specialized extracellular matrix at the axon initial segment. J. Cell Biol. 178, 875–886 (2007).

  14. 14.

    , & Identification of a conserved ankyrin-binding motif in the family of sodium channel alpha subunits. J. Biol. Chem. 278, 27333–27339 (2003).

  15. 15.

    et al. A targeting motif involved in sodium channel clustering at the axonal initial segment. Science 300, 2091–2094 (2003).

  16. 16.

    et al. Neurofascins are required to establish axonal domains for saltatory conduction. Neuron 48, 737–742 (2005).

  17. 17.

    Polarized domains of myelinated axons. Neuron 40, 297–318 (2003).

  18. 18.

    & The making of a node: a co-production of neurons and glia. Curr. Opin. Neurobiol. 23, 1049–1056 (2013).

  19. 19.

    & Molecular mechanisms of node of Ranvier formation. Curr. Opin. Cell Biol. 20, 616–623 (2008).

  20. 20.

    , & Organization and maintenance of molecular domains in myelinated axons. J. Neurosci. Res. 91, 603–622 (2013).

  21. 21.

    et al. Deletion of PIK3C3/Vps34 in sensory neurons causes rapid neurodegeneration by disrupting the endosomal but not the autophagic pathway. Proc. Natl. Acad. Sci. USA 107, 9424–9429 (2010).

  22. 22.

    , , & Retina- and ventral forebrain-specific Cre recombinase activity in transgenic mice. Genesis 26, 130–132 (2000).

  23. 23.

    , & 440-kD ankyrinB: structure of the major developmentally regulated domain and selective localization in unmyelinated axons. J. Cell Biol. 123, 1463–1473 (1993).

  24. 24.

    , & Morphogenesis of the node of Ranvier: co-clusters of ankyrin and ankyrin-binding integral proteins define early developmental intermediates. J. Neurosci. 17, 7025–7036 (1997).

  25. 25.

    et al. A distal axonal cytoskeleton forms an intra-axonal boundary that controls axon initial segment assembly. Cell 149, 1125–1139 (2012).

  26. 26.

    et al. Spectrins and ankyrinB constitute a specialized paranodal cytoskeleton. J. Neurosci. 26, 5230–5239 (2006).

  27. 27.

    , , & Nervous system defects of AnkyrinB(−/−) mice suggest functional overlap between the cell adhesion molecule L1 and 440-kD AnkyrinB in premyelinated axons. J. Cell Biol. 143, 1305–1315 (1998).

  28. 28.

    & The membrane attachment protein for spectrin is associated with band 3 in human erythrocyte membranes. Nature 280, 468–473 (1979).

  29. 29.

    et al. Hereditary spherocytosis associated with deletion of human erythrocyte ankyrin gene on chromosome 8. Nature 345, 736–739 (1990).

  30. 30.

    et al. Dependence of nodal sodium channel clustering on paranodal axoglial contact in the developing CNS. J. Neurosci. 19, 7516–7528 (1999).

  31. 31.

    et al. Protein kinase CK2 contributes to the organization of sodium channels in axonal membranes by regulating their interactions with ankyrin G. J. Cell Biol. 183, 1101–1114 (2008).

  32. 32.

    et al. Mutant β-spectrin 4 causes auditory and motor neuropathies in quivering mice. Nat. Genet. 29, 61–65 (2001).

  33. 33.

    , , , & βIV spectrins are essential for membrane stability and the molecular organization of nodes of Ranvier. J. Neurosci. 24, 7230–7240 (2004).

  34. 34.

    Node of Ranvier disruption as a cause of neurological diseases. ASN Neuro 5, 209–219 (2013).

  35. 35.

    , , & Determinants of voltage-gated sodium channel clustering in neurons. Semin. Cell Dev. Biol. 22, 171–177 (2011).

  36. 36.

    et al. Ankyrin-G directly binds to kinesin-1 to transport voltage-gated Na+ channels into axons. Dev. Cell 28, 117–131 (2014).

  37. 37.

    & Organizing the fluid membrane bilayer: diseases linked to spectrin and ankyrin. Trends Mol. Med. 14, 28–36 (2008).

  38. 38.

    et al. Assembly and maintenance of nodes of Ranvier rely on distinct sources of proteins and targeting mechanisms. Neuron 73, 92–107 (2012).

  39. 39.

    et al. Glial ankyrins facilitate paranodal axoglial junction assembly. Nat. Neurosci. 10.1038/nn.3858 (2 November 2014).

  40. 40.

    & Restriction of 480/270-kD ankyrin G to axon proximal segments requires multiple ankyrin G-specific domains. J. Cell Biol. 142, 1571–1581 (1998).

  41. 41.

    & Postmitotic expression of ankyrinR and beta R-spectrin in discrete neuronal populations of the rat brain. J. Neurosci. 13, 3725–3735 (1993).

  42. 42.

    & Distinct ankyrin isoforms at neuron cell bodies and nodes of Ranvier resolved using erythrocyte ankyrin-deficient mice. J. Cell Biol. 114, 1243–1259 (1991).

  43. 43.

    et al. Purkinje cell degeneration associated with erythroid ankyrin deficiency in nb/nb mice. J. Cell Biol. 114, 1233–1241 (1991).

  44. 44.

    & Spinal cord disease in hereditary spherocytosis: report of two cases with a hypothesized common mechanism for neurologic and red cell abnormalities. Blood 48, 259–263 (1976).

  45. 45.

    et al. E-cadherin polarity is determined by a multifunction motif mediating lateral membrane retention through ankyrin-G and apical-lateral transcytosis through clathrin. J. Biol. Chem. 288, 14018–14031 (2013).

  46. 46.

    , , , & The lethal hemolytic mutation in beta I sigma 2 spectrin Providence yields a null phenotype in neonatal skeletal muscle. Lab. Invest. 74, 1117–1129 (1996).

  47. 47.

    et al. betaIV spectrin, a new spectrin localized at axon initial segments and nodes of ranvier in the central and peripheral nervous system. J. Cell Biol. 151, 985–1002 (2000).

  48. 48.

    et al. A rat brain Na+ channel alpha subunit with novel gating properties. Neuron 1, 449–461 (1988).

  49. 49.

    , , , & Does paranode formation and maintenance require partitioning of neurofascin 155 into lipid rafts? J. Neurosci. 24, 3176–3185 (2004).

  50. 50.

    , , , & Membrane domain organization of myelinated axons requires betaII spectrin. J. Cell Biol. 203, 437–443 (2013).

  51. 51.

    et al. Guideline to reference gene selection for quantitative real-time PCR. Biochem. Biophys. Res. Commun. 313, 856–862 (2004).

Download references

Acknowledgements

We thank K. Susuki for discussions. This research was supported by US National Institutes of Health grants NS044916 (MNR), NS069688 (MNR), NS49119 (ECC), the Dr. Miriam and Sheldon G. Adelson Medical Research Foundation, and CURE (Citizens United for Research on Epilepsy). V.B. is an investigator of the Howard Hughes Medical Institute.

Author information

Affiliations

  1. Program in Developmental Biology, Baylor College of Medicine, Houston, Texas, USA.

    • Tammy Szu-Yu Ho
    • , Kae-Jiun Chang
    •  & Matthew N Rasband
  2. Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA.

    • Daniel R Zollinger
    • , Edward C Cooper
    •  & Matthew N Rasband
  3. Department of Neurology, Baylor College of Medicine, Houston, Texas, USA.

    • Mingxuan Xu
    •  & Edward C Cooper
  4. Department of Pathology, Yale University, New Haven, Connecticut, USA.

    • Michael C Stankewich
  5. Department of Cell Biology, Duke University, Durham, North Carolina, USA.

    • Vann Bennett

Authors

  1. Search for Tammy Szu-Yu Ho in:

  2. Search for Daniel R Zollinger in:

  3. Search for Kae-Jiun Chang in:

  4. Search for Mingxuan Xu in:

  5. Search for Edward C Cooper in:

  6. Search for Michael C Stankewich in:

  7. Search for Vann Bennett in:

  8. Search for Matthew N Rasband in:

Contributions

M.N.R. and T.S.-Y.H. conceived the project, designed the experiments and wrote the manuscript. D.R.Z. performed the electrophysiology experiments and analyzed the data. M.N.R. performed intravitreal injections of AAV. T.S.-Y.H. performed all other experiments and analyzed the data. K.-J.C. supervised the RT-qPCR experiments. K.-J.C., M.X., E.C.C., M.C.S. and V.B. provided crucial reagents, mice and support.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Matthew N Rasband.

Integrated supplementary information

Supplementary information

About this article

Publication history

Received

Accepted

Published

DOI

https://doi.org/10.1038/nn.3859

Further reading