FGF-18 is a neuron-derived glial cell growth factor expressed in the rat brain during early postnatal development.
We examined the expression of fibroblast growth factor-18 (FGF-18) in the rat brain during postnatal development by in situ hybridization. FGF-18 was transiently expressed at the early postnatal stages in various regions of the rat brain including the cerebral cortex and hippocampus. FGF-18 in the brain was preferentially expressed in neurons but not in glial cells. To elucidate the role of FGF-18 in the brain, we examined the ligand-specificity of FGF-18 by the BIAcore system. FGF-18 was found to bind to FGF receptors (FGFRs)-3c and -2c but not to FGFR-1c, suggesting that FGF-18 acts on glial cells but not on neurons. Therefore, we examined the mitogenic activity of FGF-18 for cultured rat astrocytes and microglia. FGF-18 was found to have mitogenic activity for both astrocytes and microglia. We also examined the neurotrophic activity of FGF-18 for cultured rat cortical neurons. FGF-18 was found to have no neurotrophic activity. The present findings indicated that FGF-18 is a unique FGF that plays a role as a neuron-derived glial cell growth factor in early postnatal development when gliogenesis occurs.
Hoshikawa
Masamitsu
M
Department of Genetic Biochemistry, Kyoto University Graduate School of Pharmaceutical Sciences, Yoshida-Shimoadachi, Sakyo, Kyoto 606-8501, Japan.
Yonamine
Akiko
A
Konishi
Morichika
M
Itoh
Nobuyuki
N
D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D001921:Brain / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D005346:Fibroblast Growth Factors / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000502:physiology*; D017628:Microglia / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009457:Neuroglia / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011505:Protein-Tyrosine Kinases; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D051498:Receptor, Fibroblast Growth Factor, Type 3; D017468:Receptors, Fibroblast Growth Factor / Q000187:drug effects / Q000378:metabolism
D008869:Microtubule-Associated Proteins; D012333:RNA, Messenger; D017468:Receptors, Fibroblast Growth Factor; C113569:fibroblast growth factor 18; D005346:Fibroblast Growth Factors; D011505:Protein-Tyrosine Kinases; D051498:Receptor, Fibroblast Growth Factor, Type 3