Fig. 1.
Pdx1 induces insulin expression in FH-B-TPN cells. (a) Diagram of the pONY4-Pdx1 viral vector. Transcription of the vector genome is driven by the human cytomegalovirus immediate-early enhancer/promoter (CMVP) fused to the R and U5 regions of the 5′ long terminal repeat of equine infectious anemia virus (EIAV). PGKP, phosphoglycerate kinase 1 promoter; IRES, internal ribosomal entry site; Neo, neomycin resistance gene; WHV posttranscriptional regulatory element of woodchuck hepatitis virus; rev, EIAV gene encoding the Rev protein; Δenv, mutated EIAV env gene. (b–e) Histological analyses of FH-B-TPN cells. (b) Nuclear PDX1 rhodamine-immunofluorescence. (c) Phase contrast image of a ball-shaped cluster formed in a confluent culture. (d) Cytoplasmic insulin Cy2-immunofluorescence. (e) Phase contrast image of the same field shown in d. b and d do not show the same field. FH-B cells were negative for staining for both proteins (data not shown). (Scale bar, 10 μm.)