Cryopreservation Induces Acetylation of Metabolism-Related Proteins in Boar Sperm

Abstract

Cryodamage affects the normal physiological functions and survivability of boar sperm during cryopreservation. Lysine acetylation is thought to be an important regulatory mechanism in sperm functions. However, little is known about protein acetylation and its effects on cryotolerance or cryodamage in boar sperm. In this study, the characterization and protein acetylation dynamics of boar sperm during cryopreservation were determined using liquid chromatography–mass spectrometry (LC-MS). A total of 1440 proteins were identified out of 4705 modified proteins, and 2764 quantifiable sites were elucidated. Among the differentially modified sites, 1252 were found to be upregulated compared to 172 downregulated sites in fresh and frozen sperms. Gene ontology indicated that these differentially modified proteins are involved in metabolic processes and catalytic and antioxidant activities, which are involved in pyruvate metabolism, phosphorylation and lysine degradation. In addition, the present study demonstrated that the mRNA and protein expressions of SIRT5, IDH2, MDH2 and LDHC, associated with sperm quality parameters, are downregulated after cryopreservation. In conclusion, cryopreservation induces the acetylation and deacetylation of energy metabolism-related proteins, which may contribute to the post-thawed boar sperm quality parameters.

Semen quality and frozen semen production in Pasundan bulls: A molecular weight perspective on seminal plasma and spermatozoa protein

“…This involves the removal of ROS produced during mitochondrial metabolism [25] . SIRT5 affects spermatozoa motility, acrosome integrity, and mitochondrial Em, essential parameters for sperm fertility [26] . Furthermore, proteins with an MW of 50–65 kDa in spermatozoa could include the IZUMO1 protein located in the acrosomal membrane.…”

Protein Post-Translational Modifications Based on Proteomics: A Potential Regulatory Role in Animal Science

“…Among 2764 comparable sites, 1252 sites were up-regulated, and only 172 were down-regulated, indicating that freezing promoted the acetylation of sperm proteins. Similarly, knocking down Sirt5 elevates levels of sperm protein acetylation, resulting in morphological impairments similar to those caused by freezing …”