Nlrp2 is Required for Early Embryonic Development Statistical analysis The results are presented as the mean 6 SEM. Data were analyzed by one-way ANOVA and LSD tests using the SPSS 13.0 software (SPSS Inc., Chicago, IL, USA). The difference was considered statistically significant at P,0.05. Author Contributions Conceived and designed the experiments: HP YZ. Performed the experiments: HP BHC CLL JMS YYW PL YSW JL FSQ ZKG. Analyzed the data: HP BHC YZ. Contributed reagents/materials/analysis tools: HP BHC. Wrote the paper: HP YZ. Editorial assistance: BW Z. Acknowledgments The authors thank Prof. Suzhu Qing for helpful discussion. We are also thankful to Dr. Yuan Yu, Guangdong Hu and Yuanyuan Yang for their generous technical assistance. References 1. Latham KE (1999) Mechanisms and control of embryonic genome activation in mammalian embryos. Int Rev Cytol 193: 71–124. 2. Christians E, Davis AA, Thomas SD, Benjamin IJ (2000) Maternal effect of Hsf1 on reproductive success. 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