Tissue and developmental expression of zebrafish gpia and gpib. (A) Northern analysis of gpia and gpib mRNA in adult tissues. The positions of 28S and 18S rRNA are indicated. (B) Northern analysis of gpia mRNA at various stages of zebrafish development. (C, D) RT-PCR analysis showing the expression of gpia and gpib in adult tissues (C) and at various developmental stages (D). Marker, 100 bp marker with the brightest band at 800 bp; -, negative control using water as template. PCR amplified 683 bp, 402 bp, and 492 bp fragments from gpia, gpib and β-actin cDNA, respectively. β-Actin was used as a reference gene for control of the amount of RNA input and sensitivity of RT-PCR analysis.

Differential expression patterns of gpia and gpib during zebrafish embryonic development. Whole-mount in situ hybridized embryos showing gpia (A–H), gpib (I–Q) mRNA expression, and a control embryo hybridized with gpia sense probe (R). The hour post fertilization for each embryo is shown at the bottom corner. (D′, H′, N′, Q′) are higher magnification views of (D, H, N, Q) respectively. (G′, H″, H′″, O′) are transverse cryosections through the embryos in (G, H, O) at the levels indicated by dotted lines, respectively. Section in (H″) was counterstained with Nuclear Fast Red. Abbreviations: gu, primitive gut; h, heart; p, pectoral fin; ph, pharyngeal arches; sb, smooth muscle cell layer of developing swim bladder; l, liver; i, intestinal epithelia; t, tectum; g, ganglion cell layer; n, inner nuclear layer of the retina; ysn, yolk syncytial nuclei; 1–7 ph, the first to the seventh pharyngeal arch.