Research Paper Volume 11, Issue 7 pp 1965—1976

SIRT6 participates in the quality control of aged oocytes via modulating telomere function

Figure 2. Telomere dysfunction and DNA damage in aged oocytes and embryos. (A) Relative telomere length in oocytes and two-cell embryos is expressed as a T/S ratio determined by quantitative RT-PCR analysis. Data are expressed as mean percentage ± SD of three independent experiments (oocytes: n=114 young, n=106 old; embryos: n=85 young, n=86 old). (B) Representative images of oocytes/two-cell embryos stained with antibodies against TRF1 (red) and γH2AX (green), and co-stained with Hoechst 33342 for chromosomes (blue). PB, polar body. Scale bars, 25 µm. (CD) Quantification of DNA damage-induced foci (TIFs) from (B). TIFs were detected by co-localization of TRF1 and γ-H2AX, and cells with at least 3 TIFs were scored. Data represent averages of 3–10 fields. Error bars indicate SD (oocytes: n=24 young, n=26 old; embryos: n=35 young, n=38 old). Statistical analyses were performed with Student’s t-test. *P <0.05, **P <0.01.