title: Brevican, a chondroitin sulfate proteoglycan of rat brain, occurs as secreted and cell surface glycosylphosphatidylinositol-anchored isoforms.
abstract: cDNA clones encoding proteins related to the aggrecan/versican family of proteoglycan core proteins have been isolated with antisera against rat brain synaptic junctions. Two sets of overlapping cDNAs have been characterized that differ in their 3'-terminal regions. Northern analyses with probes derived from unique regions of each set were found to hybridize with two brain-specific transcripts of 3.3 and 3.6 kilobases (kb). The 3.6-kb transcript encodes a polypeptide that exhibits 82% sequence identity with bovine brevican and is thought to be the rat ortholog of brevican. Interestingly, the polypeptide deduced from the open reading frame of the 3.3-kb transcript is truncated just carboxyl-terminal of the central domain of brevican and instead contains a putative glypiation signal. Antibodies raised against a bacterially expressed glutathione S-transferase-brevican fusion protein have been used to show that both soluble and membrane-bound brevican isoforms exist. Treatment of the crude membrane fraction and purified synaptic plasma membranes with phosphatidylinositol-specific phospholipase C revealed that isoforms of brevican are indeed glycosylphosphatidylinositol-anchored to the plasma membrane. Moreover, digestions with chondroitinase ABC have indicated that rat brevican, like its bovine ortholog, is a conditional chondroitin sulfate proteoglycan. Immunohistochemical studies have shown that brevican is widely distributed in the brain and is localized extracellularly. During postnatal development, amounts of both soluble and phosphatidylinositol-specific phospholipase C-sensitive isoforms increase, suggesting a role for brevican in the terminally differentiating and the adult nervous system.
authors.affiliation: Federal Institute for Neurobiology, Magdeburg, Germany.
authors.forename: C I
authors.initials: CI
authors.lastname: Seidenbecher
authors.forename: K
authors.initials: K
authors.lastname: Richter
authors.forename: U
authors.initials: U
authors.lastname: Rauch
authors.forename: R
authors.initials: R
authors.lastname: Fässler
authors.forename: C C
authors.initials: CC
authors.lastname: Garner
authors.forename: E D
authors.initials: ED
authors.lastname: Gundelfinger
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000378:metabolism*; D058581:Brevican; D002417:Cattle; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D011508:Chondroitin Sulfate Proteoglycans / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D017261:Glycosylphosphatidylinositols / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D037181:Lectins, C-Type; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D054801:Phosphoinositide Phospholipase C; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism; D012313:RNA / Q000235:genetics / Q000378:metabolism; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D012995:Solubility; D014018:Tissue Distribution; D014162:Transfection
chemical_list: C546938:BCAN protein, human; C546939:Bcan protein, rat; D058581:Brevican; D011508:Chondroitin Sulfate Proteoglycans; D018076:DNA, Complementary; D017261:Glycosylphosphatidylinositols; D037181:Lectins, C-Type; D009419:Nerve Tissue Proteins; D011993:Recombinant Fusion Proteins; D012313:RNA; D010727:Phosphoric Diester Hydrolases; D054801:Phosphoinositide Phospholipase C; D043265:Phosphatidylinositol Diacylglycerol-Lyase