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Peri-implantation lethality in mice lacking the PGC-1-related coactivator protein
1Laboratory of Endocrine and Metabolic Diseases, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Shanghai, P. R. China.
Background:
Members of the PPARγ coactivator-1 (PGC-1) family are central transcriptional coactivators that regulate cell metabolic processes ranging from mitochondrial biogenesis to oxidative respiration. PGC-1-related coactivator (PPRC1 or PRC), initially identified as a member of the PGC-1 family, is believed to regulate mitochondria biogenesis, respiration pathways, and cell proliferation. However, its physiological role is not clearly understood. Here, we investigate the biological functions of PPRC1 in vivo using PPRC1 deficient mice generated by gene targeting.
Results:
Homozygous deficient PPRC1 mice failed to form egg cylinders and died after implantation but before embryonic day 6.5, whereas mice heterozygous for PPRC1 were viable, fertile and indistinguishable from their wild-type littermates. Furthermore, PPRC1 mRNA was expressed at the embryonic stage before implantation and was rapidly up-regulated during the first day of embryoid body formation. The PPRC1 mRNA was then subsequently down-regulated, although its precise function at this stage of development was unclear.
Conclusions:
This is the first study to suggest a nonredundant role for PPRC1 in mouse early embryonic development.
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