Fig. 2: Analysis of oyster ILPs and Pdx gene expression.

a qPCR survey of gene expression levels in oyster tissues for cgMIP123, cgMIP4, cgMILP7, cgILP and cgPdx. Within each gene, qPCR results were normalised to the average value of the tissue with the highest relative quantification (RQ). Error bars represent 95% confidence intervals around the mean of RQs (n = 1 cDNA sample mixed from three animals). Three (cgILP and cgPdx) or four (cgMIP123, cgMIP4 and cgMILP7) technical replications were conducted. Lpa labial palps, Gil gill, Man mantle, Wam white adductor muscle, Tam transparent adductor muscle, Neu neuron, Hea heart, Hem haemolymph, Mgo male gonad, Fgo female gonad, Hep hepatopancreas, Sto stomach, Int intestine. Broad blue arrows leading from qPCR panels to rows of images indicate in situ hybridisation analysis using the indicated genes (b–m). White arrows point to sites of gene expression. Adjacent sections were used to compare sense controls (b, e, h, k) with antisense tests (c, d, f, g, i, j, l, m), to compare expression between cgMIP123 and cgMIP4, and to compare cgILP and cgPdx gene expression. c, d Adult section showing cgMIP123 expression in a branchial neuron (possibly the cerebro-visceral connective). f, g Adjacent sections showing cgMIP4 expression in identical sites to cgMIP123. i, j Sections showing cgILP expression in the stomach wall and ducts of the hepatopancreas. l, m Adjacent sections showing cgPdx expression in identical sites to cgILP, except for additional staining of cgPdx RNA in parts of the gut wall (compare panel m to j). Abbreviations (pointed by black arrows): st stomach, in intestine, lp labial palps, ma mantle, ne neuron, hp hepatopancreas. Bar under each panel marks, 500 μm (b, c, e, f, h, i, k, l), 250 μm (j, m), 15 μm (d, g). Representative of at least two independent experiments for b–m. Source data are provided as a Source Data file.