Evidence of Enhanced Energy Production and Transfer, Synthesis of Nucleotides, Ribosome Assembly, and Protein Translation in Breast Muscle in High vs Low Feed Efficiency Pedigree Broiler Males: Hypotheses Worth Pursuing?

Global gene (cDNA microarray, RNAseq) and protein expression (shotgun proteomics) analyses have been conducted on breast muscle samples obtained from pedigree broiler males exhibiting high and low feed efficiency (FE) phenotypes. Through carefully cataloging expression analyses, it has been possible to begin to develop a unique proteogenomic picture of FE at the cellular/molecular level in muscle. Predicted activation of electron transport chain activity, and expression of a) adenine nucleotide translocase (ANT) and voltage dependent activated channel (VDAC), proteins that shuttle ADP and ATP in and out of the mitochondria, and b) mitochondrial and cytosolic creatine kinase (CK) suggests energy production and transfer activity is enhanced in high FE muscle. Increased expression of rate limiting enzymes and other components involved in nucleotide (NADH), purine and pyrimidine metabolism indicates that the synthesis of essential building blocks for RNA and DNA may be favored in high FE. Finally, expression of several genes/proteins associated with ribosomal assembly and activity suggest that translation mechanisms may also be enhanced in the high FE breast muscle. We feel these results are important in generating hypotheses to be tested regarding fundamental mechanisms of FE. Funding provided by USDA-NIFA (#2013-01953), Arkansas Biosciences Institute (Little Rock, AR) and the Agricultural Experiment Station (Univ. of Arkansas).