Differential expression of genes associated with prenatal protein under-nutrition by albumen removal in the chicken

Previously, long-term effects on body weight and reproductive performance have been demonstrated in the chicken model of prenatal protein undernutrition by albumen removal. Introduction of such persistent alterations in phenotype suggests stable changes in gene expression. A genome-wide screening for differences in hepatic transcriptome by RNA-Seq was performed in adult Isa Brown hens (55 weeks of age). Albumen-deprived hens were created by removal of 3 ml of the albumen from fertilized eggs and replacement with saline early during embryonic development (embryonic day 1). Results were compared to mock-treated sham hens and non-treated control hens. Correlation between relative expression levels obtained from the RNA-Seq and qPCR results was very high (Pearson’s correlation coefficiënt = 0.85), confirming the validity of the RNA-Seq results. In addition, after expansion of the sample size, 7 out of 15 selected genes demonstrated the same significant gene expression differences in the qPCR as in the RNA-Seq dataset, and were thus biologically confirmed. Grouping of the differentially expressed (DE) genes according to biological functions revealed the involvement of processes such as ‘embryonic and organismal development’, ‘organ morphology’, ‘organ and tissue development’, ‘reproductive system development and function’. Molecular pathways that were altered were ‘amino acid metabolism’, ‘molecular transport’, ‘small molecule biochemistry’, ‘cell death and survival’, ‘cell-to-cell signaling and interaction’, ‘carbohydrate metabolism’ and ‘protein synthesis’. In conclusion, the present results demonstrated for the first time that prenatal protein undernutrition by albumen removal leads to long-term alterations of the hepatic transcriptome in the chicken. Overall design: 3 biological replicates per group (control, sham, albumen-deprived) were analyzed

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Willems E, Guerrero-Bosagna C, Decuypere E, Janssens S, Buyse J, Buys N, Jensen P, Everaert N