Characterization of Zebrafish von Willebrand Factor Reveals Conservation of Domain Structure, Multimerization, and Intracellular Storage

Figure 4

Developmental expression of vwf mRNA. Wild type zebrafish offspring were isolated from 8 to 120 hpf, fixed, and in situ hybridization was performed (Section 2). (a) Examination at 8 hpf demonstrates weak expression throughout the entire embryo, and staining was completely absent from a sense control. (b) Diffuse expression continues at 12 hpf (staining was completely absent from a sense control), followed by more restricted expression cranially with a stripe that extends caudally at 48 hpf (c). Figure 4(d) is a sense probe as negative control at 48 hpf. (e) 96 hpf shows strong expression in the pharyngeal arches. (f) RT-PCR of cDNA isolated from whole zebrafish embryos and larvae from 8–96 hpf. (g, h) Analysis at 120 hpf shows continued expression in the pharyngeal arches, as well as inner yolk sac layer and intestinal epithelium. Experiments in (a–e) used full length vwf riboprobes. Results in (g, h) are representative of hybridization with exon 28 and exon 47–52 riboprobes (Section 2, Table 1). Abbreviations: p: pharyngeal arches; y: inner layer of yolk sac; i: intestinal epithelium.