Figure 1.

Identification of coiled. Ten kilodalton Texas-Red-labeled dextran was injected into stage 17 embryos of the genotypes indicated. Homozygous mutant embryos were identified using GFP-labeled balancer chromosomes. A–E, Frontal views of ventral nerve cords or trachea (A′–E′). A, No penetration of fluorescently labeled dextran was observed into the nerve cord of stage 17 wild-type embryos. B–E, Fluorescently labeled dextran penetrates into the ventral nerve cord of embryos homozygous for several different chromosomal deficiencies. The trachea in mutant embryos show a convoluted phenotype and are leaky.