Protein profile and reactive oxygen species production in mitochondria from pigs divergently selected for residual feed intake

Abstract

Residual feed intake (RFI) is a production efficiency measurement used to account for average daily gain and backfat of an animal. Less efficient animals have greater levels of oxidative stress. A major source of in vivo oxidative stress is the mitochondria. In this study the protein profile of mitochondria was investigated to determine differences between pigs genetically selected for high and low RFI (less and more efficient, respectively). Mitochondria were isolated from the red and white portions of the semitendinosus muscle (STR and STW respectively), from the longissimus dorsi (LD) muscle, and the liver from pigs (n = 24, 12 per line) genetically selected for low or high RFI. Mitochondrial protein differences between lines were determined using 2-D DIGE, and spots were identified using electrospray ionization mass spectroscopy. Heat shock protein (HSP) 60 and HSP70, which have been linked to anti-apoptotic pathways in the mitochondria, were increased in the low RFI line. Endoplasmic reticulum oxidase-1 α (ERO1α) was decreased in LD mitochondria from the low RFI line. The protein profile of mitochondria from the more efficient pigs