Multiple molecular weight forms of basic fibroblast growth factor are developmentally regulated in the central nervous system

Basic fibroblast growth factor can mediate the early inductive events in renal development.

“…bovine kidney has been used in the past for purification purposes as an enriched source of both FGF2 (25) and FGF1 (29). In the developing metanephros, an undefined heparinbinding protein of 16-20 kDa with angiogenic activity has been identified in mouse renal rudiments at gdll, which is the developmental equivalent of gdl3 in rat, and represents a preinduction state in renal organogenesis (30 (38), it has also been shown to regulate cell adhesion (39) (43), and (25,43) adult tissues. Although Lombard and Grobstein (44) reported that the ability of brain to serve as an inductor of kidney tubule formation diminished with maturation and that the adult brain was incapable of inducing tubulogenesis, it was also observed that both embryonic and adult brain tissue could induce the formation of condensates of mesenchyme (18) similar to those generated here with FGF2.…”

Fibroblast growth factor 2 up regulates telomerase activity in neural precursor cells

“…These neural stem cells could self renew and di erentiate into cells of all neural lineages via restricted progenitor cells in¯uenced by intrinsic and environmental factors (Cattaneo and McKay, 1990;Qian et al, 1997;Reynolds et al, 1992). FGF2 (®broblast growth factor 2), also known as basic ®broblast growth factor is widely expressed in embryonic CNS (Giordano et al, 1992). There are increasing evidences that FGF2 may be one of the main regulators of CNS development (Dono et al, 1998;Murphy et al, 1994;Ray et al, 1997;Vaccarino et al, 1999).…”

Fibroblast growth factor 2 increases Otx2 expression in precursor cells from mammalian telencephalon

“…These factors are likely to affect the development of the forebrain. Basic Fibroblast growth factor (FGF2) is expressed at early stages of neurogenesis in the developing mammalian forebrain (Powell et al, 1991b;Giordano et al, 1992) where several high affinity FGF receptor types (FGFR-1, FGFR-2, and FGFR-3) are expressed in the proliferative ventricular zone (Heuer et al, 1990;Wanaka et al, 199 1;Orr-Urtreger et al, 1991;Peters et al, 1993). This pattern is strikingly similar to the localization of Otx2, which is localized in the ventricular proliferative layer of the mesencephalon, diencephalon, and telencephalon (Simeone et al, 1993;Frantz et al, 1994), and suggests that Otx2 may be expressed by progenitor cells receptive to FGF2.…”

“…Thus, the striking increase in the number of Otx2-containing cells after FGF2 treatment, and the fact that this FGFZmediated increase correlates with the temporal pattern of expression in vivo, suggest an important role of endogenous FGF2 in the stimulation of Otx2 expression. The expression of FGF2 and its receptors overlap spatially and temporally with the expression of Otx2 (Powell et al, 1991a;Giordano et al, 1992;Nurcombe et al, 1993;Weise et al, 1993). The FGF-Rl, FGF-R2, and FGF-R3 have been localized within the germinal ventricular layer of the telencephalon at-early stages of development (Heuer et al, 1990;Orr-Urtreger et al, 1991;Wanaka et al, 1991;Peters et al, 1993).…”

“…The differential response of dorsal and basal telencephalic cells to FGF2 may be due to a differential distribution of FGF receptor subtypes on their membranes secondary to their regulation by different FGF-related members. For example, FGF-7 is selectively expressed at E14.5 in the ventricular layer of the ganglionic eminence, the parietal and the frontal cortex, whereas Int2 and FGF5 are broadly expressed in germinative layers from earlier stages (E9) (Wilkin-son et al, 1987;Giordano et al, 1992;Mason et al, 1994). It remains to be determined whether Otx2-containing cells also express a particular FGF2 receptor subtype which is differentially distributed in the telencephalon.…”