Expression of the Atlantic salmon zlg mRNA. A) Expression of the zonadhesin-like gene was analyzed in a variety of tissues. Ten micrograms of total RNA from liver, brain, spleen, kidney, midgut, hindgut, foregut and gonads from male and female Atlantic salmon was blotted on a positively charged nylon membrane and hybridized with radiolabeled probe 1 representing the 3'-end of the Atlantic salmon zlg mRNA. B) Analysis of the Atlantic salmon zlg tissue expression pattern by semi-quantitative reverse transcription PCR. Zlg primers ('probe 1' primer set) were used to test for the presence of the zlg cDNA. The EST to which the primers were designed [GenBank: CK990464] and BAC 722P12 were used as positive controls. The genomic region encompassed by the primers contains two introns of 395 and 441 bp yielding a 1219 bp band upon amplification. C) Ubiquitin primers were used as a positive control for mRNA presence. zlg (ZAN neg) and ubiquitin (Ubi neg) template-free negative controls were included.