Xenopus sperm is better at supporting development than a spermatid or a somatic cell. (A) Experimental design for the generation of cloned embryos. The somatic nucleus of a gastrula cell is transplanted to a UV-enucleated egg. The resulting embryos are scored at the gastrulation and tadpole stage. (B) Scoring of embryos as % of gastrulae and as % of swimming tadpoles to the total number of cleaved embryos. Average of n = 6 independent experiments (sperm ICSI), and n = 3 independent experiments (embryo cell NT). The total number of embryos analyzed is shown above the graph. Error bars: SEM. (*) P-value < 0.05 (χ2 test). (C) Experimental design for the generation of sperm- and spermatid-derived embryos. Permeabilized sperm or spermatids are injected to the cytoplasm (ICSI) of an unfertilized egg. The resulting embryos are scored at the gastrulation and tadpole stage. (D) Representative images of sperm- and spermatid-embryos. Scale bars = 1 mm. (E) Scoring of embryos as % of gastrula and as % of swimming tadpoles to the total number of cleaved embryos (average of n = 6 independent experiments). The total number of embryos analyzed is shown above the graph. Error bars: SEM. (*) P-value < 0.05 (χ2 test).
