Identification of versican as an isolectin B4-binding glycoprotein from mammalian spinal cord tissue.
Nociceptors are specialized nerve fibers that transmit noxious pain stimuli to the dorsal horn of the spinal cord. A subset of nociceptors, the nonpeptidergic C-fibers, is characterized by its reactivity for the plant isolectin B4 (IB4) from Griffonia simplicifolia. The molecular nature of the IB4-reactive glycoconjugate, although used as a neuroanatomical marker for more than a decade, has remained unknown. We here present data which strongly suggest that a splice variant of the extracellular matrix proteoglycan versican is the IB4-reactive glycoconjugate associated with these nociceptors. We isolated (by subcellular fractionation and IB4 affinity chromatography) a glycoconjugate from porcine spinal cord tissue that migrated in SDS/PAGE as a single distinct protein band at an apparent molecular mass of > 250 kDa. By using MALDI-TOF/TOF MS, we identified this glycoconjugate unambiguously as a V2-like variant of versican. Moreover, we demonstrate that the IB4-reactive glycoconjugate and the versican variant can be co-released from spinal cord membranes by hyaluronidase, and that the IB4-reactive glycoconjugate and the versican variant can be co-precipitated by an anti-versican immunoglobulin and perfectly co-migrate in SDS/PAGE. Our findings shed new light on the role of the extracellular matrix, which is thought to be involved in plastic changes underlying pain-related phenomena such as hyperalgesia and allodynia.
Bogen
Oliver
O
Freie Universität Berlin, Institut für Chemie-Biochemie, Thielallee, Berlin, Germany.
Dreger
Mathias
M
Gillen
Clemens
C
Schröder
Wolfgang
W
Hucho
Ferdinand
F
D000595:Amino Acid Sequence; D000818:Animals; D011508:Chondroitin Sulfate Proteoglycans / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D002846:Chromatography, Affinity; D006023:Glycoproteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D006821:Hyaluronoglucosaminidase / Q000378:metabolism; D037102:Lectins / Q000378:metabolism*; D037181:Lectins, C-Type; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000378:metabolism; D011509:Proteoglycans / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013116:Spinal Cord / Q000737:chemistry / Q000378:metabolism*; D013347:Subcellular Fractions; D013552:Swine; D053675:Versicans
D011508:Chondroitin Sulfate Proteoglycans; D006023:Glycoproteins; D037102:Lectins; D037181:Lectins, C-Type; D010446:Peptide Fragments; D011509:Proteoglycans; D053675:Versicans; D006821:Hyaluronoglucosaminidase