Fig. 4

Fgf8a Stimulates Notch Signaling and MG Quiescence

(A) mCherry and glutaminesynthetase (GS) immunofluorescence in tp1:mCherry transgenic fish treated with or without the Notch signaling inhibitors DAPT or RO 4929097. Scale bar, 100 μm.

(B) mCherry and BrdU immunofluorescence in tp1:mCherry transgenic fish at various times post-retinal injury. Arrowheads point to areas of reduced mCherry expression in the INL. Asterisk indicates injury site (central retina, 6-month-old fish). Scale bar, 100 μm.

(C) BrdU immunofluorescence in WT fish retina 4 days after intravitreal injection of DMSO or DAPT. Scale bar, 100 μm.

(D) mCherry and BrdU immunofluorescence in injured (Inj) retinas from tp1:mCherry and hsp70:fgf8a;tp1:mCherry transgenic fish that received HS from 1–2 dpi. Asterisk indicates injury site (central retina, 6-month-old fish); arrows point to BrdU+/mCherry− cells. Scale bar, 100 μm.

(E) BrdU immunofluorescence at 4 dpi in WT and hsp70:fgf8a fish that were immersed in fish water with or without DAPT and received HS over 4 days. Asterisk indicates injury site (central retina, 6-month-old fish). Scale bar, 100 μm. Graph shows quantification of BrdU+ cells; n = 3 individual experiments. Error bars indicate SD. ^∗∗p < 0.01.

(F) RT-PCR analysis of indicated RNAs in uninjured (Uninj) and injured (6 hpi) retinas from WT fish (1, 2, and 3 are triplicate samples).

(G) qPCR quantification of dll4 and hey1 gene expression in WT and hsp70:fgf8a fish that received a 1-hr HS at the time of injury and were sacrificed 5 hr later; n = 3 individual experiments. Error bars indicate SD. ^∗p < 0.05.

(H) pPCR as in (G), but HS was for 2 days, and gene expression was assayed 2 days later; n = 3 individual experiments. Error bars indicate SD. ^∗p < 0.05.

See also Figure S4.