Comparative proteomic analysis of Tibetan pig spermatozoa at high and low altitudes

Yanling Zhao,Qiang Fu,Yangzong Qiangba,Zhipeng Cheng,Zili Ren,Mengfang Tian,Xiaoli Lu

doi:10.1186/s12864-019-5873-0

Abstract

BackgroundTo illuminate the mechanisms underlying the high-altitude tolerance of Tibetan pig spermatozoa, proteomes of spermatozoa from Tibetan pigs raised in high and low altitudes were compared using a tandem mass tag (TMT)-labeled quantitative proteomics approach.ResultsA total of 77 differentially expressed proteins (DEPs) were identified. Gene Ontology (GO) analysis revealed DEPs that were predominantly associated with the actin cytoskeleton, the tricarboxylic acid (TCA) cycle, and adenosine triphosphate (ATP) metabolism, and were from 12 enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Three subnetworks were significantly enriched and 10 centric proteins were identified by protein-protein interaction (PPI) network analysis. Relative expression levels of the proteins (ATP5H, CYCS, MYH9 and FN1) were confirmed using Western blotting.ConclusionsOur study is the first to use a tandem mass tag (TMT) approach to analyze Tibetan pig spermatozoa, and provides a foundation to understand the mechanisms underlying the reproductive adaptations of Tibetan pigs to high-altitude environments.

Highlights

To illuminate the mechanisms underlying the high-altitude tolerance of Tibetan pig spermatozoa, proteomes of spermatozoa from Tibetan pigs raised in high and low altitudes were compared using a tandem mass tag (TMT)-labeled quantitative proteomics approach
These results indicate that the male reproductive system of Tibetan pigs was adapted to high-altitude conditions
A total of 1392 proteins were identified from 5625 unique peptides by quantitative proteomic analysis (FDR < 1%)

Summary

Introduction

To illuminate the mechanisms underlying the high-altitude tolerance of Tibetan pig spermatozoa, proteomes of spermatozoa from Tibetan pigs raised in high and low altitudes were compared using a tandem mass tag (TMT)-labeled quantitative proteomics approach. The Qinghai-Tibetan plateau is an extreme environment with an average altitude of more than 4000 m [1]. Tibetan pigs are a unique and geographically isolated pig breed that inhabits high-altitude regions of the QinghaiTibetan plateau. They exhibit heritable adaptations to their high-altitude environments as a result of natural selection [2]. A series of studies have identified distinct physiological traits that contribute to the survival of Tibetan pigs on a high plateau [3, 4]. Transcriptional and proteomic analyses have revealed the expression of hypoxia regulators to enable adaptation to high-altitude conditions [5,6,7,8]

Methods

Results

Discussion

Conclusion