Fig. 5.

Phenotype rescue by transgenic MSX2A expression. a Construct A contains a 5.6 kb genomic fragment that includes the two exons of MSX2A (yellow) and surrounding non-coding DNA (blue). An eGFP reporter with lens-specific promoter is included to help identify transgenics. b Construct B expresses both eGFP and MSX2A under the control of the MSX2A-CNE (cloned as five concatenated copies) and an inducible hsp70 promoter. The 2A peptide linker allows expression of two products from a single transcript. c Results from three experiments in which the marine MSX2A allele was expressed in transgenic freshwater fish (PAXB population). The first two experiments compare GFP-expressing mosaic transgenics injected with construct A to sibling controls that either were not injected or showed no expression. The third experiment results from the cross of a construct B founder transgenic fish to a wild-type PAXB fish. GFP-expressing fish (carriers of the stable transgene) were compared to siblings lacking the transgene. Length measurements are the residuals of DS2 length from a linear regression on standard length. P-values are from Welch’s t-test. eGFP enhanced green fluorescent protein, PAXB Paxton Lake benthic population