Mitochondrial behaviors in the vitrified mouse oocyte and its parthenogenetic embryo: effect of Taxol pretreatment and relationship to competence  Chang-Liang Yan, Ph.D., Xiang-Wei Fu, M.S., Guang-Bin Zhou, Ph.D., Xue-Ming Zhao, Ph.D., Lun Suo, M.S., Shi-En Zhu, Ph.D.  Fertility and Sterility  Volume 93, Issue 3, Pages 959-966 (February 2010) DOI: 10.1016/j.fertnstert.2008.12.045 Copyright © 2010 American Society for Reproductive Medicine Terms and Conditions

Figure 1 Mitochondriallocalization in mouse oocytes after different treatments. In the Control group (A–A″), mitochondria with low △ψ were spot-like and distributed homogeneously in the cytoplasm of oocytes, while mitochondria with high △ψ were aggregated in cortical regions (arrow), forming the “J-aggregates.” In the Vit group (C–C″), clustered mitochondria (C, arrowhead) existed in the cytoplasm. In the Tox (B–B″) and Tax (D–D″) groups, the mitochondria localization patterns were similar to those of the Control group. Mitochondria in all treated oocytes were more centered compared with those of control oocytes (two-headed arrow), with fewer J-aggregates in the cortical region (arrow). Green: mitochondria with low △ψ. Red: mitochondria with high △ψ. Yellow: merging of green and red images. Fertility and Sterility 2010 93, 959-966DOI: (10.1016/j.fertnstert.2008.12.045) Copyright © 2010 American Society for Reproductive Medicine Terms and Conditions

Figure 2 Time-lapse images of oocytes with different treatments after bleaching. Bleached areas are circled with red lines. (pb: polar body.) Fertility and Sterility 2010 93, 959-966DOI: (10.1016/j.fertnstert.2008.12.045) Copyright © 2010 American Society for Reproductive Medicine Terms and Conditions

Figure 3 Fluorescence recovery curves of oocytes with different treatments after bleaching. (A) Green and red fluorescence exhibited similar fluorescence recovery curves. (B) Oocytes in the Vit and Tax groups recovered faster than those in the Tox and control groups and showed different recovery curves. Fertility and Sterility 2010 93, 959-966DOI: (10.1016/j.fertnstert.2008.12.045) Copyright © 2010 American Society for Reproductive Medicine Terms and Conditions

Figure 4 Mitochondria localization and fluorescence recovery rate of oocytes with different treatments. (A) The rate of oocytes showing homogeneous or heterogeneous mitochondrial localization patterns are different among treatments. Homogeneous: mitochondria were spot-like and homogeneously distributed in the cytoplasm. Heterogeneous: mitochondria were heterogeneously distributed in the cytoplasm. (B) Fluorescence recovery rate of vitrified oocytes is statistically significantly increased. (C) Perinuclear or nonperinuclear mitochondrial localization pattern of two-cell parthenogenetic embryos from Vit group oocytes is statistically significantly changed. Note: a, b, and c denote a statistically significantly difference within the same bars. Fertility and Sterility 2010 93, 959-966DOI: (10.1016/j.fertnstert.2008.12.045) Copyright © 2010 American Society for Reproductive Medicine Terms and Conditions

Figure 5 Mitochondria localization and fluorescence recovery rate of oocytes with different treatments. In the Control group (A, B), mitochondria were perinuclear localized and formed continuous rings (arrows). In the Tox (C) or Vit (D, E) groups, mitochondria were distributed either in the cortical region (D and E, arrowhead) or through the cytoplasm (E, arrowhead), and unevenly among the blastomeres (E). In the Tax group (F), mitochondria exhibited the perinuclear localization pattern (arrows) but with some mitochondria still localized in the cortical region (arrowhead). Fertility and Sterility 2010 93, 959-966DOI: (10.1016/j.fertnstert.2008.12.045) Copyright © 2010 American Society for Reproductive Medicine Terms and Conditions