Brevican isoforms associate with neural membranes

Authors

  • Constanze I. Seidenbecher,

    1. AG Molecular Mechanisms of Plasticity, Department of Neurochemistry/Molecular Biology, Leibniz Institute for Neurobiology Magdeburg,Germany
    Search for more papers by this author
  • Karl-Heinz Smalla,

    1. AG Molecular Mechanisms of Plasticity, Department of Neurochemistry/Molecular Biology, Leibniz Institute for Neurobiology Magdeburg,Germany
    2. FAN GmbH, Magdeburg, Germany
    Search for more papers by this author
  • Nora Fischer,

    1. AG Molecular Mechanisms of Plasticity, Department of Neurochemistry/Molecular Biology, Leibniz Institute for Neurobiology Magdeburg,Germany
    Search for more papers by this author
  • Eckart D. Gundelfinger,

    1. AG Molecular Mechanisms of Plasticity, Department of Neurochemistry/Molecular Biology, Leibniz Institute for Neurobiology Magdeburg,Germany
    Search for more papers by this author
  • Michael R. Kreutz

    1. AG Molecular Mechanisms of Plasticity, Department of Neurochemistry/Molecular Biology, Leibniz Institute for Neurobiology Magdeburg,Germany
    Search for more papers by this author

Address correspondence and reprint requests to Constanze I. Seidenbecher, AG Molecular Mechanisms of Plasticity, Department of Neurochemistry/Molecular Biology, Leibniz Institute for Neurobiology, 39118 Magdeburg, Germany. E-mail: seidenc@ifn-magdeburg.de

Abstract

Brevican is a neural-specific proteoglycan of the brain extracellular matrix, which is particularly abundant in the terminally differentiated CNS. It is expressed by neuronal and glial cells, and as a component of the perineuronal nets it decorates the surface of large neuronal somata and primary dendrites. One brevican isoform harbors a glycosylphosphatidylinositol anchor attachment site and, as shown by ethanolamine incorporation studies, is indeed glypiated in stably transfected HEK293 cells as well as in oligodendrocyte precursor Oli-neu cells. The major isoform is secreted into the extracellular space, although a significant amount appears to be tightly attached to the cell membrane, as it floats up in sucrose gradients. Flotation is sensitive to detergent treatment. Brevican is most prominent in the microsomal, light membrane and synaptosomal fractions of rat brain membrane preparations. The association with the particulate fraction is in part sensitive to chondroitinase ABC and phosphatidylinositol-specific phospholipase C treatment. Furthermore, brevican staining on the surface of hippocampal neurons in culture is diminished after hyaluronidase or chondroitinase ABC treatment. Taken together, this could provide a mechanism by which perineuronal nets are anchored on neuronal surfaces.

Ancillary