Fig. 10. Co-expression of Six3 and bHLH genes. (A) Schematic structure of retroviral vectors. The bHLH genes (Math3, NeuroD) were fused with GFP, and Six3 has three repeats of Myc tag. (B) Retinal explants were infected with CLIG-Six3 (a), CLIG-Six3-Math3 (b) and CLIG-Six3-NeuroD (c). After 2 weeks of culture, the explants were sectioned and subjected to immunohistochemistry for Myc and calbindin. Misexpression of Six3 alone generates some INL cells, but they are negative for calbindin expression (a). Co-expression of Six3 and Math3/NeuroD increases the population of calbindin-positive cells (b,c, arrowheads). Scale bar: 25 µm. (C) Ratios of amacrine (a) and horizontal cells (b). Co-expression of Six3 and NeuroD efficiently generates amacrine cells while co-expression of Six3 and Math3 efficiently generates horizontal cells.
