Amino-terminal sequences of a novel heparin-binding protein from human, bovine, rat, and chick brain: high interspecies homology.
Recently, the partial structural characterization of a novel bovine brain protein was reported (1). Because of its mitogenic activity for vascular endothelial cells and its ability to strongly bind heparin it was termed heparin-binding brain mitogen (HBBM). Although HBBM shares these properties with members of the fibroblast growth factor (FGF) family of growth factors, its amino-terminal sequence is not homologous to that of the FGFs. Now, we report the isolation and partial structural characterization of HBBMs from human, rat and chick brain. Proteins were isolated by tissue extraction at pH 4.5, ammonium sulfate precipitation, cation exchange chromatography, heparin-Sepharose affinity chromatography and reverse-phase HPLC. The amino-terminal sequences of the HBBMs from human, bovine and rat brain are identical, whereas that of chick HBBM reveals a single amino acid substitution. The high sequence homology among the HBBMs from different species suggests an important biological role of the protein.
Huber
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D
Biochemisches Institut, Universität Zürich, Switzerland.
Gautschi-Sova
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Böhlen
P
P
D000595:Amino Acid Sequence; D000818:Animals; D001923:Brain Chemistry; D002417:Cattle; D002645:Chickens; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D006133:Growth Substances / Q000302:isolation & purification*; D006493:Heparin / Q000302:isolation & purification*; D006801:Humans; D008934:Mitogens / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D051381:Rats; D012689:Sequence Homology, Nucleic Acid
D006133:Growth Substances; D008934:Mitogens; D006493:Heparin