ZSCAN4 Regulates Zygotic Genome Activation and Telomere Elongation in Porcine Parthenogenetic Embryos.

Zinc finger and SCAN domain-containing 4 (), a DNA-binding protein, maintains telomere length and plays a key role in critical aspects of mouse embryonic stem cells, including maintaining genomic stability and defying cellular senescence. However, the effect of in porcine parthenogenetic embryos remains unclear. To investigate the function of and the underlying mechanism in porcine embryo development, was knocked down via dsRNA injection in the one-cell stage. was highly expressed in the four- and five- to eight-cell stages in porcine embryos. The percentage of four-cell stage embryos, five- to eight-cell stage embryos, and blastocysts was lower in the knockdown group than in the control group. Notably, depletion of induced the protein expression of and 5-Methylcytosine (5mC, a methylated form of the DNA base cytosine) in the four-cell stage. The H3K27ac level and ZGA genes expression decreased following knockdown. Furthermore, knockdown led to DNA damage and shortened telomere compared with the control. Additionally, -dsRNA was injected to reduce DNA hypermethylation in knockdown embryos. knockdown rescued telomere shortening and developmental defects caused by knockdown. In conclusion, is involved in the regulation of transcriptional activity and is essential for maintaining telomere length by regulating expression in porcine ZGA.