Fig. 6. Expression of NGF in the E6 chick retina. RT-PCR with NGF- and GAPDH-specific primers was performed as described (see Materials and Methods). The PCR products were separated on a 2% agarose gel and stained with ethidium bromide. NGF is detectable in both control and anti-TGF-ß-treated retinae. NGF, lane 4 (control) and lane 5 (anti-TGF-ß); GAPDH, lane 9 (control) and lane 10 (anti-TGF-ß). PCR with crude RNA preparations revealed no amplification product (lanes 2,3,7,8), ruling out cross contamination with genomic DNA. M, marker lane.