Low-oxygen conditions abolish developmental defects induced by Sirt3 knockdown.
(A) Intracytoplasmic injection of Sirt3 siRNA did not affect 2-cell and blastocyst formation rates in low-oxygen (5% O2) conditions. Data are derived from 4 independent experiments. (B) Effects of siRNA-mediated Sirt3 knockdown on intracellular ROS levels, as estimated by CM-H2DCFDA fluorescence intensity, in 20% and 5% O2 conditions. Sirt3 knockdown–induced ROS increases were canceled in 5% O2 conditions. Data are derived from 3 independent experiments. Statistical assessments were performed by applying Games-Howell test. *P < 0.05. (C) Representative images of CM-H2DCFDA fluorescence in embryos analyzed in B. Scale bar: 100 μm.