In vivo validation of zebrafish first intron promoter
and enhancer activity.
A. LEFT: 5’ deletion series of the zebrafish
5’ homology arm upstream of the transgenic cassette
(lcp1:Cre-P2A-EGFP-CAAX, abbreviated ‘EGFP’).
Constructs are numbered according to the number of bases upstream of the
engineered translation start site (ATG, where
A = +1.) A. RIGHT: Results of
deletion-series injections. Green bars = proportion of injected embryos with
EGFP + EVL cells. Gray lines = 95% confidence interval on the
proportion.
B-F. Animal cap views of injected, EGFP +
embryos collected at 50% epiboly.
G. Annotation of the minimal intronic region (−481
to −169) sufficient for EVL activity. The deletion-construct forward PCR
primers are underlined. The predicted transcript is in
UPPER CASE. TATA = TATA box motif; TSS = transcription
start site; DPE = downstream promoter element. The EST
‘foothill’ (See Figs. 7 and
8) is shaded yellow.