Updated project metadata.
Cryopreservation induces differential remodeling of the proteome in mammalian spermatozoa. How these proteome changes relate with the loss of sperm function during cryopreservation remains unsolved. The present study attempted to clarify this issue evaluating differential changes in the proteome of pig spermatozoa retrieved from the cauda epididymis and the ejaculate, with clear differences in cryotolerance, comparing fresh and frozen-thawed cells. Sperm samples were collected from 10 healthy, sexually mature and fertile boars, and cryopreserved using a standard 0.5 mL straw protocol. Total and progressive motility, viability and mitochondria membrane potential were higher and membrane fluidity and reactive oxygen species generation lower in frozen-thawed (FT) cauda epididymal than ejaculated spermatozoa. Quantitative proteomics of fresh and FT sperm samples were analyzed using a LC-ESI-MS/MS-based SWATH approach. Cryopreservation quantitatively altered more proteins in ejaculated than cauda epididymal spermatozoa. Differential protein-protein networks highlighted a set of proteins directly involved in mitochondrial functionality among those quantitatively altered in ejaculated spermatozoa, which would explain the worse post-thaw quality of ejaculated pig spermatozoa.