The zebrafish apoA-IV genes have unique expression patterns in the YSL, intestine and liver. Developmental mRNA expression dynamics of the zebrafish apoA-IV genes, as measured by ISH, during somitogenesis [15-20 somite (S)] and at 1-6 dpf. All four apoA-IV genes showed earliest mRNA expression at 15-20 S in the YSL; the mRNAs localize to distinct subregions of the YSL until 5 dpf. All four genes are expressed in the intestine (I) at 4-6 dpf, with weak intestinal expression observed for apoA-IVa, and apoA-IVb.3 is expressed in the liver (L) at 4-6 dpf. No expression was observed for the apoA-IV genes at the eight-cell stage, 30% epiboly or 80-100% epiboly (supplementary material Fig. S4). Larvae from 15-20 S to 5 dpf are wild type (2-5 dpf treated with PTU; 6-dpf larvae are nacre-/-. Experiments were performed in triplicate with ne5 embryos or larvae per probe in every experiment.