Comparative Proteomic Analysis of Yak Follicular Fluid during Estrus

Differential proteomic analysis demonstrates follicle fluid participate immune reaction and protein translation in yak

Background

Ovarian follicle fluid (FF) as a microenvironment surrounding oocyte plays critical roles in physio-biochemical processes of follicle development and oocyte maturation. It is hypothesized that proteins in yak FF participate in the physio-biochemical pathways. The primary aims of this study were to find differentially expressed proteins (DEPs) between mature and immature FF, and to elucidating functions of the mature and immature FF in yak.

Results

The mature and immature FF samples were obtained from three healthy yaks that were nonpregnant, aged from four to five years, and free from any anatomical reproductive disorders. The FF samples were subjected to mass spectrometry with the isobaric tags for relative and absolute quantification (iTRAQ). The FF samples went through correlation analysis, principle component analysis, and expression pattern analysis based on quantification of the identified proteins. Four hundred sixty-three DEPs between mature and immature FF were identified. The DEPs between the mature and immature FF samples underwent gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and protein-protein interaction (PPI) analysis. The DEPs highly expressed in the mature FF mainly took parts in the complement and coagulation cascades, defense response, acute-phase response, response to other organism pathways to avoid invasion of exogenous microorganisms. The complement activation pathway contains eight DEPs, namely C2, C5, C6, C7, C9, C4BPA, CFH, and MBL2. The three DEPs, CATHL4, CHGA, and PGLYRP1, take parts in defense response pathway to prevent invasion of exogenetic microorganism. The coagulation cascades pathway involves many coagulation factors, such as F7, F13A1, FGA, FGB, FGG, KLKB1, KNG1, MASP1, SERPINA1, and SERPIND1. While the DEPs highly expressed in the immature FF participated in protein translation, peptide biosynthetic process, DNA conformation change, and DNA geometric change pathways to facilitate follicle development. The translation pathway contains many ribosomal proteins, such as RPL3, RPL5, RPS3, RPS6, and other translation factors, such as EIF3J, EIF4G2, ETF1, MOV10, and NARS. The DNA conformation change and DNA geometric change involve nine DEPs, DDX1, G3BP1, HMGB1, HMGB2, HMGB3, MCM3, MCM5, MCM6, and RUVBL2. Furthermore, the expressed levels of the main DEPs, C2 and SERPIND1, were confirmed by western blot.

Conclusions

The differential proteomics revealed the up-regulated DEPs in mature FF take parts in immunoreaction to prevent invasion of microorganisms and the up-regulated DEPs in immature FF participate in protein synthesis, which may improve our knowledge of the follicular microenvironment and its biological roles for reproductive processes in yak. The DEPs, C2 and SERPIND1, can be considered as protein markers for mature yak follicle.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-021-03097-0.

Salidroside influences the cellular cross-talk of human fetal lung diploid fibroblasts: A proteomic approach

Senescence is a complex multiple factor proces, which is still poorly understood. The purpose of this study was to find the proteome of cultured human fetal lung diploid fibroblasts (2BS) of different population doubling (PD), as well as the altered proteome induced by salidroside (SAL) in 2BS cells. Proteins were identified by two-dimensional electrophoresis (2-DE) combining matrix-assisted laser desorption/ionization-time and flight mass spectrometry (MAL DI-TOF/MS). As a result, we found 16 proteins with two-fold variations in senescent cells or after SAL treatment, some being reduced such as reticulocalbin-1, heat shock protein beta-6, elongation factor 1-delta, F-actin-capping protein subunit alpha-1, and chloride intracellular channel 1. In contrast, 40S ribosomal protein SA, proteasome subunit alpha type-5, and zinc finger BED domain-containing protein 5 increased with cell age. Furthermore, heat shock protein beta-6, Zinc finger BED domain-containing protein 5 was increased in PD30 cells after 10 μM SAL treatment, whereas, elongation factor 1-delta, 6-phosphogluconolactonase, Nucleoside diphosphate kinase A, F-actin-capping protein subunit alpha-1, Probable ATP-dependent RNA helicase DDX41, Chloride intracellular channel 1, and Peroxiredoxin-6 were increased in PD50 cells after 10 μM SAL treatment. Some of these proteins were involved in the protein synthetic and degradative pathways, which emphasizes the metabolic disorder or functional impairment of cell senescence. Moreover, these proteins could be candidate biomarkers for evaluating the SAL anti-senescence effect.