BK1 - AN FGF-RESPONSIVE CENTRAL NERVOUS SYSTEM-DERIVED CELL-LINE

Fibroblast growth factors (FGF) are expressed at high levels in the ce ntral nervous system (CNS), however their function in the CNS is not w ell understood. The immortalized neuronal cell line (BK1), derived fro m a transgenic mouse central nervous system tumor, expresses high leve ls of FGF receptor 1 (FGFR1) and demonstrates both morphologic and bio chemical changes when treated with basic FGF (FGF-2). We have derived subclones of BK1 cells with varying degrees of FGF responsiveness by t ransfecting either a wild type (FRW) or a truncated (FRX) form of FGFR 1. Cells expressing high levels of FGFR1 rapidly and uniformly respond to FGF, while cells expressing FRX fail to respond to FGF, either mor phologically or by the expression of molecular markers. These BK1 subc lones will prove useful to study FGFR mediated signal transduction and FGFR responsive genes in a Ch'S derived cell. These studies also demo nstrate that a dominant negative FGF receptor can be used as a tool to elucidate the function of FGF in the central nervous system.