SWATH-MS quantitative proteomic analysis of deer antler from two regenerating and mineralizing sections

Abstract

Antlers are the only organ in the mammalian body that regenerates each year. Theycan reach growth rates of 1–3 cm/day in length and create more than 20 cm2/day of skin in theantler tips (their growth centers). Previous proteomic studies regarding antlers have focused onantler growth centers (tips) compared to the standard bone to detect the proteins involved in tissuegrowth. However, proteins of cell differentiation and regeneration will be more accurately detectedconsidering more growing tissues. Thus, we set out to compare proteins expressed in antler tips (thehighest metabolism rate and cell differentiation) vs. middle sections (moderate cell growth involvingbone calcification), using ribs as controls. Samples were obtained in mid-June with antlers’ phenologycorresponding to the middle of their growth period. Quantitative proteomic analysis identified259 differentially abundant proteins mainly associated with antioxidant metabolic mechanisms,protein formation and Wnt signalling pathway, meanwhile, the mid antler section was linked toblood proteins. The high metabolic rate and subsequent risk of oxidative stress also seem to haveresulted in strong antioxidant mechanisms. These results suggest that redox regulation of proteins isa key factor in the model of deer antler regeneration.