Transcription of developmentally important genes is misregulated in spermatid-derived embryos compared to sperm-derived embryos. (A) Schematic representation of paternally derived haploid embryos generated by UV enucleation of eggs followed by intra-cytoplasmic sperm injection (ICSI). (B) Developmental advantage of sperm over spermatid is maintained in haploid embryos. Embryos were scored as the % of embryos reaching a gastrula stage and a swimming tadpole stage to the total number of cleaved embryos (average of n = 3 independent experiments). Numbers of embryos analyzed are indicated above the bars. Error bars: SEM. (*) P-value < 0.05 (χ2 test). (C) Genes important for development are misregulated (mostly up-regulated) in spermatid-derived embryos. Heat map representing log fold-change in expression levels of the 100 genes (rows) misregulated in spermatid versus sperm gastrula embryos (FDR < 0.05; red: up-regulated; blue: down-regulated in spermatid) across seven independent experiments (columns). (D) Developmentally important gene ontology terms enriched in the list of misregulated genes (P-value < 0.05). (E) Up-regulation of genes in spermatid-derived embryos does not correlate with their transcription in spermatid. Density scatter plot showing gene expression in spermatid-derived embryos versus that in spermatids. No correlation is observed between the two parameters for all genes (r = 0.06) as well as for the misregulated genes (red dots, r = −0.17).
