Microarray and qPCR Analysis of Mitochondrial Metabolism Activation during Prenatal and Early Postnatal Development in Rats and Humans with Emphasis on CoQ10 Biosynthesis

During the mammalian ontogenesis, a rapid switch from glycolytic metabolism to oxidative phosphorylation must proceed during postnatal adaptation to extra-uterine conditions. It was proposed that in the course of intra-uterine fetal development, expression changes proceed to cover all metabolic demands all along this critical and extremely fast period. Using microarray techniques, quantitative PCR, enzyme activities’ and coenzyme Q content measurements, we describe perinatal mitochondrial metabolism acceleration in rat liver and skeletal muscle between the 16th day of gestation and the first days of life and possible correlation with results in human. Out of 1546 mitochondrial genes, 72% and 53% were significantly changed in liver and skeletal muscle, respectively. The most important expression shift occurred in the liver at least two days before parturition. We used microarrays to detail the orchestration of gene expression underlying perinatal metabolic shift and identified up- and down-regulated genes during this process. Rattus norvegicus perinatal liver and skeletal muscle tissues were selected as a model of mammalian adaptation to extra-uterine conditions. To study gene expression, we used Affymetrix microarrays. Analysis wasperformed by The Centre for Applied Genomics, The Hospital for Sick Children, Toronto, Canada. For analysis we used tissues at five time-points: fetal day 16 (F16), fetal day 20 (F20), last day before parturition - fetal day 22 (F22), first postnatal day (P1) and 4th postnatal day (P4). We obtained also data from fetal day 18 (in skeletal muscle) and 90th day of life (liver, “adult” control), which were not used in analysis, but are part of this data submission. For liver tissue analysis, we used four biological replicates per time-point. For skeletal muscle analysis, five biological replicates were used.