Smooth muscle mitogen

摘要

A novel growth factor (BTC-GF) was purified from the conditioned medium of pancreatic beta tumor cells initially derived from transgenic mice (RIPI-Tag2). The purification scheme included BioRex 70 chromatography, phenyl-Sepharose chromatography, TSL-GEL heparin FPLC and C4 reverse phase HPLC. The peptide also stimulated proliferation of bovine smooth muscle cells. It was not inactivated by boiling, by 10 mM dithiothreitol or by exposure to 1M acetic acid. Biological activity of BTC-GF was recovered from a single band of protein which had a molecular weight of 32,000 on SDS-PAGE. The partial N-terminal amino acid sequence of this protein from BTC-3 and BTC-J10 cells was determined with an ABI 470A protein sequencer to be: (SEQ ID NO: 1) An internal region amino acid sequence of BTC-GF was determined to be: (SEQ ID NO: 3)