Distribution of functional Magp1-mRFP protein during early development. DNA encoding the Magp1-mRFP fusion construct was injected into wild-type embryos, yielding a mosaic distribution of the fusion protein as observed at 12 hours after fertilization (data not shown). By 24 hours, the Magp1-mRFP fusion protein exhibited localized tissue distribution. (A) Coinjection of the Magp1-mRFP fusion construct alleviated the vascular defects in magp1 morphant embryos (compare columns 2 and 1). Error bars indicate SEM. (B) Bright-field image of a wild-type embryo at 24 hours after fertilization. (C) Wild-type embryo injected with 12 pg Magp1-mRFP fusion construct under rhodamine illumination, showing enrichment of the Magp1 protein around the notochord (arrowheads) and in the dorsal connective tissues (arrows). (D) Tg(fli1/EGFP) embryo injected with 12 pg Magp1-mRFP fusion construct, showing the endothelium-lined vasculature under FITC illumination. (E) Distribution of Magp1-mRFP fusion protein is visualized under the rhodamine filter. (F) Overlay of panels D and E, showing the enrichment of the Magp1-mRFP fusion protein around the developing vasculature. (G) Inset from panel F, as indicated by the rectangle in panel F, showing the Magp1-mRFP fusion protein to be in close association with the endothelial cells (arrows). Anterior is to the left for all panels. (B-G) Original magnifications, 5 ×.