Figure 3

The klar^MW allele does not support normal lipid-droplet transport in embryos. (A) Embryos were fixed and stained with Nile Red to reveal lipid droplets. In all genotypes shown, lipid droplets are spread throughout the periphery in Phase I and move inward in Phase II. In the wild type, lipid droplets shift back into the periphery in Phase III. In klar^YG3 and klar^MW, the bulk of lipid droplets remains in the central yolk in Phase III. (B) Living embryos were placed in halocarbon oil and imaged by bright-field microscopy after Phase III, as described [19, 22]. Embryo transparency reveals global lipid-droplet distribution [19]. Klar^YG3, klar^MW, and GFP-LD klar^YG3 embryos display a transparent periphery, indicating that lipid droplets failed to spread out from their inward accumulation in Phase II. For all other genotypes shown, embryos are opaque, characteristic of normal outward droplet transport. Normal transport in the wild-type strain Tai255.1 has been observed previously [58].