Expression of GH/IGFI axis genes during larval development. Gene expression levels (linear), from 1 to 33 dph, of S. solea transcripts codifying key genes of the GH/IGFI pathway. A. S. solea GH and GHRH transcripts; B. S. solea IGFI and IGFIR transcripts. Graphics show mean gene expression measured with microarray, bars indicate standard deviation (SD) across biological replicates. Statistical significance (p < 0.05) when comparing one larval stage against the previous one is indicated by asterisk (*).