(A–B) Analysis of lateral mesodermal cell migration defects in cxcr4a mutant embryos by in situ hybridization for fn1a. Mesodermal cell migration is normal in stable cxcr4a single mutants. toddler;cxcr4a double mutants show mesodermal cell migration defects that resemble toddler single mutant siblings. (C) Representative images of embryos analyzed in D and E. In situ hybridization for sox17 at 75% epiboly; dorsal to the right. Cxcr4a morphants and cxcr4a mutants have excessive animal pole-directed migration of vegetal endoderm. Endoderm patterning in toddler;cxcr4a double mutants resembles wild-type embryos more than toddler single mutant siblings. (D) Measurement of frequency with which cells were found at a given location in an embryo of a certain genotype. A cell at the animal pole corresponds to 100% embryo height, while a cell at the vegetal pole corresponds to 0%. AP = Animal pole=100%; VP = vegetal pole=0%. (E) The number of lateral endodermal cells is unchanged between toddler single and toddler;cxcr4a double mutants. Each point represents a single embryo. Red bars are averages. (B and E) ns: p>0.46; *p<0.05; **p<0.0005; unpaired two-tailed t-test. N = number of independent experiments; n = number of embryos.
