Global proteomic analysis of serum during early pregnancy in the pig using data-independent acquisition mass spectrometry with verification by parallel reaction monitoring

Abstract

Context The current pregnancy diagnosis is generally not ideal in accuracy and efficiency, and the physiological process of early pregnancy in pig remains unclarified. Aims This study aimed to evaluate protein expression profiles and identify typical proteins of early pregnancy for more understanding of physiological processes. Methods Data-independent acquisition-based (DIA) quantitative proteomic analysis was performed to compare the serum proteome profiles on days 0, 5, 12, 16, and 19 of gestation in Tibetan pig. Parallel reaction monitoring (PRM) was subsequently performed to verify relative expression level. Key results 396 proteins were detected, of which 113 differentially expressed proteins (DEPs) were identified. Functional annotation and pathway analysis indicated that the DEPs were mainly involved in catalytic activity, metabolic processes and the proteasome. Four candidate DEPs (talin 1, profilin, carbonic anhydrase, and HGF activator) showed consistent expression trends in both DIA and PRM approaches. Conclusions The DIA based proteomic methods indicate the involvement of numerous serum proteins in early pregnancy physiological function in pigs. The combination of DIA-PRM based global proteomic analysis may provide insights for function study and pregnancy diagnosis biomarkers. Implications The global proteomic analyses performed here have increased the knowledge of early pregnancy in Tibetan swine and provide potential methods for pregnancy detection.