Unraveling proteome changes and potential regulatory proteins of bovine follicular Granulosa cells by mass spectrometry and multi-omics analysis

Metabolic status is a key factor influencing proteomic changes in ewe granulosa cells induced by chronic BPS exposure

BACKGROUND

Bisphenol S (BPS) is the main substitute for bisphenol A (BPA), a well-known plasticiser and endocrine disruptor. BPS disrupts ovarian function in several species. Moreover, a few studies have reported that the effects of BPS might be modulated by the metabolic status, and none have characterised the granulosa cell (GC) proteome after chronic BPS exposure.

OBJECTIVES

This study aimed to decipher the mechanisms of action of chronic BPS exposure on the proteome of ewe GCs while considering the interaction between a deliberate contrasted metabolism and reproductive function.

METHODS

Forty ewes were split into two groups with contrasted diets: restricted (R, n = 20) and well-fed (WF, n = 20). The R and WF ewes were subdivided according to the dose of BPS administered through the diet (0-50 µg/kg/day), forming four groups: R0, R50, WF0 and WF50. After 3-month BPS daily exposure, GCs were recovered during the pre-ovulatory stage and proteins were analysed by nano-liquid chromatography coupled with tandem mass spectrometry.

RESULTS

Chronic exposure to BPS affected the GC proteome differently according to the ewe metabolic status. Fifty-nine out of 958 quantified proteins were differentially abundant between groups and are mainly involved in carbohydrate and lipid pathways. Unsupervised hierarchical clustering of differentially abundant proteins (DAPs) identified four clusters of 34, 6, 5 and 14 proteins according to the BPS exposure and diet interaction. Pairwise comparisons between groups also revealed a strong effect of BPS exposure and diet interaction. Functional analysis of DAPs highlighted that BPS upregulated β-glucuronidase (GUSB; p = 0.002), a protein especially able to deconjugate bisphenol glucuronides (BP-g). Moreover, among unexposed ewes, GUSB was detected only in well-fed ewes.

DISCUSSION

Conjugation of glucuronides inhibits the oestrogenic activity of bisphenols. Upregulation of GUSB in ewes dosed with BPS would prolong the oestrogenic effects of BPS by deconjugating BPS-g into free BPS. In addition, literature has reported an up-regulation of GUSB in people suffering from obesity. Therefore, people suffering from obesity could be subjected to prolonged and aggravated exposure to BPS. These data highlighted the deleterious effects of BPS and its interaction with metabolic status.

Fibronectin 1 supports oocyte in vitro maturation in pigs

Oocyte in vitro maturation (IVM) based on the follicular fluid (FF) environment can exploit untapped resources, however, what FF factors regulate oocyte maturation remains unclear. This work demonstrated that serum and FF significantly promoted oocyte polar body extrusion (PBE) and subsequent embryo development, and FF was especially effective. Fibronectin 1 (FN1) was predicted as one potential candidate to regulate oocyte maturation by proteomics. FN1 transcription obviously decreased, and the protein expression significantly increased and migrated to plasma membrane or even outside during oocyte IVM. Treatment with 10 ng/mL FN1 significantly improved oocyte PBE rate. FN1 significantly upregulated the percentage of regular spindle morphology, downregulated the γ-H2AX level, decreased the levels of ROS and apoptosis, and increased GSH and mitochondrion contents by ameliorating the expression of corresponding genes. Moreover, FN1 significantly increased the p-PI3K level to enhance the activation of PI3K signaling pathway. In conclusion, this study discovers and confirms that FN1 is one factor in FF that significantly enhances oocyte maturation, and the underlying mechanism is that FN1 ameliorates oocyte nuclear and cytoplasmic maturation by promoting the activation of PI3K signaling pathway.

Comprehensive proteomic profiling of early antral follicles from sheep

The present study evaluates the proteome of early antral follicles from Ovis aries. Fifty follicles were collected from ovaries of adult ewes and extracted proteins were trypsin-digested, desalted and analyzed by LC-MS/MS. Genes were screened for potential modulation by miRNAs and protein data, subjected to functional enrichment analysis. Label-free mass spectrometry allowed the identification of 2503 follicle proteins, confirming vimentin, actin, lamin, heat shock proteins and histones as the most abundant ones. In silico analyses indicated that miRNAs modulate the expression of genes coding proteins of the sheep follicles involved in cell cycle, cell differentiation, aging, apoptosis, cell death, adipocyte differentiation, cell division. The most important biological processes associated with the follicle proteins were innate immune response, translation, adaptive immune response and protein folding, while molecular functions linked to the proteome of sheep antral follicles related to metal ion binding, ATP binding, oxygen binding, RNA binding and GTP binding, among others. Upload of 2503 Uniport accession codes through DAVID platform matched 1274 genes, associated with translation, metabolic process, proteolysis involved in cellular protein catabolic process, zona pellucida receptor complex and others. KEEG pathways analysis indicated genes correlated with ovine follicular development, with major pathways listed as carbon metabolism, biosynthesis of amino acids, glutathione metabolism, oxidative phosphorylation, fatty acid degradation and oocyte meiosis. This represents a comprehensive atlas of proteins expressed in sheep early antral follicles and will contribute to future identification of biomarkers for follicular development and oocyte maturation.

Effects of a gel culture system made of polysaccharides (xanthan gum and locust bean gum) on in vitro bovine oocyte development and gene expression of the granulosa cells

Xanthan gum (XG) and locust bean gum (LBG) are nontoxic polysaccharides that produce culture substrates. The present study examined the effect of XG-LBG gel on in vitro bovine oocyte growth and gene expression in granulosa cells. Oocytes and granulosa cell complexes (OGCs) were cultured in vitro on plastic culture plate (Plate) or XG-LBG gel for 16 days. OGCs formed a dome-like cavity surrounding the oocytes on plate but formed a spherical follicle structure on XG-LBG gel. The total granulosa cell numbers of the OGCs and their survival rate was greater for OGCs cultured on XG-LBG gel than for those cultured on plate. Oocytes grown on XG-LBG gels had higher lipid and mitochondrial content, as well as a larger diameter, than their plate counterparts. When oocytes grown in vitro were subjected to in vitro maturation and fertilization, the normal fertilization rate was significantly higher for oocytes developed on XG-LBG gel than that of oocytes cultured on the plate counterpart. RNAseq of the granulosa cells revealed that genes associated with focal adhesion, phosphatidylinositol 3'-kinase-Akt and Hippo signaling, and regulation of actin cytoskeleton were upregulated in granulosa cells of OGCs cultured on XG-LBG gel compared with those cultured on plate.

Combined transcriptome and proteome analyses reveal differences in the longissimus dorsi muscle between Kazakh cattle and Xinjiang brown cattle

Objective

With the rapid development of proteomics sequencing and RNA sequencing technology, multi-omics analysis has become a current research hotspot. Our previous study indicated that Xinjiang brown cattle have better meat quality than Kazakh cattle. In this study, Xinjiang brown cattle and Kazakh cattle were used as the research objects.

Methods

Proteome sequencing and RNA sequencing technology were used to analyze the proteome and transcriptome of the longissimus dorsi muscle of the two breeds of adult steers (n = 3).

Results

In this project, 22,677 transcripts and 1,874 proteins were identified through quantitative analysis of the transcriptome and proteome. By comparing the identified transcriptome and proteome, we found that 1,737 genes were identified at both the transcriptome and proteome levels. The results of the study revealed 12 differentially expressed genes and proteins: troponin I1, crystallin alpha B, cysteine, and glycine rich protein 3, phosphotriesterase-related, myosin-binding protein H, glutathione s-transferase mu 3, myosin light chain 3, nidogen 2, dihydropyrimidinase like 2, glutamate-oxaloacetic transaminase 1, receptor accessory protein 5, and aspartoacylase. We performed functional enrichment of these differentially expressed genes and proteins. The Kyoto encyclopedia of genes and genomes results showed that these differentially expressed genes and proteins are enriched in the fatty acid degradation and histidine metabolism signaling pathways. We performed parallel reaction monitoring (PRM) verification of the differentially expressed proteins, and the PRM results were consistent with the sequencing results.

Conclusion

Our study provided and identified the differentially expressed genes and proteins. In addition, identifying functional genes and proteins with important breeding value will provide genetic resources and technical support for the breeding and industrialization of new genetically modified beef cattle breeds.

MiR-660-5p promotes the progression of hepatocellular carcinoma by interaction with YWHAH via PI3K/Akt signaling pathway

Currently, more and more studies show that aberrantly expressed microRNAs (miRNAs) are important driving factors for the pathogenesis of hepatocellular carcinoma (HCC). Based on the TCGA and GEO databases, miR-660-5p was identified as a possible target for HCC in this study.In HCC tissues, miR-660-5pexpressionwasparticularly high, and this was confirmed inHCC cell lines. The upregulatedmiR-660-5p showed correlations with tumor size, tumor number, TNM stage and histological grade. In vitro experimental data, aswellas in vivo evidence showed that miR-660-5p has the ability to significantly enhance the cell proliferation rate, clone formation, migration, invasion, and tumorigenic capacity of HCC cells. YWHAH is validated that targeted by miR-660-5p using dual luciferase reporter assay. Knockdown of YWHAH has been shown to partially reverse the tumor suppressive function of miR-660-5p inhibitor. Furthermore, miR-660-5p/YWHAH axis could activate PI3K/AKT pathway, which promoted EMT and cell cycle processes. In conclusion, this study illustrated the function of miR-660-5p/YWHAH axis in HCC and provided potential targets for treating HCC.