Expression of CCT6A mRNA in chicken granulosa cells is regulated by progesterone

Genome-Wide Differential Expression Profiling of Ovarian circRNAs Associated With Litter Size in Pigs

Circular RNAs (circRNAs) have been emerging as an important regulator in mammalian reproduction via acting as miRNA sponges. However, the circRNAs in porcine ovaries related with litter size remains largely unknown. In this study, porcine ovaries with smaller or larger litter size (LLS) were subjected to high-throughput RNA sequencing. In total, 38,722 circRNAs were identified, of which 1,291 circRNAs were commonly expressed in all samples. There were 56 circRNAs significantly down-regulated and 54 circRNAs up-regulated in LLS pig (|log2 (fold change) | > 1, FDR < 0.05). Bioinformatics predicted that most of circRNAs harbored miRNA binding sites, and the expression patterns of circRNAs and their putative binding miRNAs were validated by qPCR. Moreover, the expression of circ-TCP11/miR-183 was significantly reversely correlated and their direct interaction was confirmed by dual-luciferase assay. Our study indicates that circRNAs may play potential effects on modulating porcine litter size.

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

Background

In previous study, we performed next-gene sequencing to investigate the differentially expressed transcripts of bovine follicular granulosa cells (GCs) at dominant follicle (DF) and subordinate follicle (SF) stages during first follicular wave. Present study is designed to further identify the key regulatory proteins and signaling pathways associated with follicular development using label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) and multi-omics data analysis approach.

Methods

DF and SF from three cattle were collected by daily ultrasonography. The GCs were isolated from each follicle, total proteins were digested by trypsin, and then proteomic analyzed via LC-MS/MS, respectively. Proteins identified were retrieved from Uniprot-COW fasta database, and differentially expressed proteins were used to functional enrichment and KEGG pathway analysis. Proteome data and transcriptome data obtained from previous studies were integrated.

Results

Total 3409 proteins were identified from 30,321 peptides (FDR ≤0.01) obtained from LC-MS/MS analysis and 259 of them were found to be differentially expressed at different stage of follicular development (fold Change > 2, P < 0.05). KEGG pathway analysis of proteome data revealed important signaling pathways associated with follicular development, multi-omics data analysis results showed 13 proteins were identified as being differentially expressed in DF versus SF.

Conclusions

This study represents the first investigation of transcriptome and proteome of bovine follicles and offers essential information for future investigation of DF and SF in cattle. It also will enrich the theory of animal follicular development.

Electronic supplementary material

The online version of this article (10.1186/s12953-019-0152-1) contains supplementary material, which is available to authorized users.

Promoter Identification and Transcriptional Regulation of the Goose AMH Gene

Simple Summary

Anti-Müllerian hormone (AMH) plays a vital role in the development of follicles. We found that the cloning nucleotide sequence of AMH was high homology in geese with other species. Several regulatory elements were identified and transcriptional factors were predicted in the AMH promoter sequence. Through a double-luciferase reporter assay, potential regulatory relationship spanning from −637 to −87 bp were identified. In addition, the mRNA expression of AMH gradually decreased during the development of follicles in geese. In the Chinese hamster ovary (CHO) cell line, the luciferase activity significantly increased by co-expression of AMH and GATA-4. However, when the binding sites of GATA-4 to the promoter of AMH were mutated, the luciferase activity significantly decreased. These results indicated that the transcription of AMH was activated by GATA-4 to inhibit the development of follicles in geese.

Abstract

Anti-Müllerian hormone (AMH) is recognized as a reliable marker of ovarian reserve. However, the regulatory mechanism of goose AMH gene remains poorly understood. In the present study, both the full-length coding sequence (CDS) and promoter sequence of goose AMH have been cloned. Its CDS consisted of 2013 nucleotides encoding 670 amino acids and the amino acid sequence contained two structural domain: AMH-N and transforming growth factor beta (TGF-β) domain. The obtained promoter sequence spanned from the −2386 bp to its transcription start site (ATG). Core promoter regions and regulatory elements were identified as well as transcription factors were predicted in its promoter sequence. The luciferase activity was the highest spanning from the −331 to −1 bp by constructing deletion promoter reporter vectors. In CHO cells, the luciferase activity significantly increased by co-expression of AMH and GATA binding protein 4 (GATA-4), while that significantly decreased by mutating the binding sites of GATA-4 located in the −778 and −1477 bp. Results from quantitative real-time polymerase chain reaction (qPCR) indicated that levels of AMH mRNA in geese granulosa layers decreased gradually with the increasing follicular diameter. Taken together, it could be concluded that the transcriptional activity of AMH was activated by GATA-4 to inhibit the development of small follicles in goose.

Expression dynamics of gonadotropin-releasing hormone-I and its mutual regulation with luteinizing hormone in chicken ovary and follicles

Gonadotropin-releasing hormone-I (GnRH-I) has been identified in the ovaries of vertebrate species, and this decapeptide is a key regulator of reproductive functions. However, its biological action and regulatory mechanism in the chicken ovary remain to be characterized. In this study, the expression of GnRH-I gene in chicken hypothalamus and ovaries at different developmental stages and different sizes of follicles was investigated, and the effect of GnRH-I mRNA on chicken follicular cells was analyzed in vitro. The results showed that the expression of GnRH-I was dramatically decreased in the hen ovary compared to that in the hypothalamus after sexual maturation. In the mature ovarian follicles, GnRH-I mRNA levels were significantly higher in theca cells than that in granulosa cells. Overexpression of GnRH-I decreased the expression of luteinizing hormone receptor (LHR) mRNA in theca cells from preovulatory follicles but had no effect on granulosa cells. Treatment of theca cells with different concentrations of luteinizing hormone (LH) significantly increased GnRH-I mRNA expression at low doses (50 ng/ml) but significantly decreased it at higher doses (200 ng/ml). Furthermore, GnRH-I inhibited LH-induced LHR expression at the lower dose of LH (50 ng/ml). These findings provide strong evidence indicating that GnRH-I is an important regulator in the chicken ovary.

Bmp4 inhibits goose granulosa cell apoptosis via PI3K/AKT/Caspase-9 signaling pathway

Bone morphogenetic protein 4 (BMP4) has an important role in regulating cellular proliferation, differentiation and apoptosis. It, however, is still unclear as to the mechanisms by which BMP4 regulates the apoptosis of granulosa cells (GCs) in geese. In the present study, there was cloning of the full-length coding sequence of goose BMP4 gene, which consisted of 1212 nucleotides encoding 403 amino acids. Its deduced amino acid sequence comprised one signal peptide, one TGFβ pro-peptide and one mature peptide domain. Results from conducting the quantitative real-time PCR (qPCR) indicated the relative abundances of BMP4 mRNA in geese GCs increased gradually from the relative abundances in pre-hierarchical follicles that were 4 to 6 mm in diameter to that in the fifth largest (F5) follicle and then relative abundances of BMP4 mRNA decreased with further development as the largest (F1) follicle. Results from use of the TUNEL assay indicated that overexpression of the goose BMP4 gene suppressed GC apoptosis and this was confirmed when relative abundances of the CAD, Caspase-9 and Caspase-3 proteins were determined using western blotting. In addition, overexpression of the BMP4 gene induced phosphorylation of AKT, which was inhibited with use of the PI3K inhibitor, LY294002. Co-transfection of BMP4 and LY294002 resulted in increased relative abundances of Caspase-9 and CAD proteins but had no effect on that of Caspase-3. Taken together, these results suggested that expression of the BMP4 gene resulted in a reduction in Caspase-9 protein leading to inhibition of GC apoptosis via the PI3K/AKT signaling pathway in geese.

Comparison of growth characteristics of in vitro cultured granulosa cells from geese follicles at different developmental stages

Granulosa cells (GCs) are essential components of follicles and are involved in regulating the process of follicles development. However, comparative studies on GCs isolated from different staged follicles have not been conducted in goose. The aim of the present study was to identify the growth characteristics of goose GCs from pre-hierarchical (6–10 mm) and hierarchical (F4–F2, F1) follicles. Our results showed that the three cohorts of cells had different tolerance to collagenase and had noticeable morphological differences. The F1 granulosa layers were fully digested by 0.1% collagenase, while higher concentration (0.3%) was used for both F4–F2 and pre-hierarchical granulosa layers. In the state of suspension, the diameter of F1 individual cell was larger than the other two cohorts. However, after adhering to the culture plate, cells of F1 just had changes in the diameter accompanied by small bright spots, while both pre-hierarchical and F4–F2 GCs proliferated rapidly with spreading and irregularly shaped voids. Furthermore, all attached cells could be stained by the follicle-stimulating hormone receptor antibody. Analyses of both growth curve and the mRNA expression profiles of genes related to cellular proliferation, apoptosis, and steroidogenesis suggested that three cohorts of in vitro cultured GCs had different physiological viability and functions. Taken together, the present study not only revealed differences of the growth characteristics among three cohorts of goose GCs from pre-hierarchical, F4–F2 and F1 follicles, but also optimized the in vitro culture system of geese different staged GCs.

Buserelin alleviates chloride transport defect in human cystic fibrosis nasal epithelial cells

Cystic fibrosis (CF) is the most common autosomal recessive disease in Caucasians caused by mutations in the gene encoding the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) chloride (Cl-) channel regulated by protein kinases, phosphatases, divalent cations and by protein-protein interactions. Among protein-protein interactions, we previously showed that Annexin A5 (AnxA5) binds to CFTR and is involved in the channel localization within membranes and in its Cl- channel function. The deletion of phenylalanine at position 508 (F508del) is the most common mutation in CF which leads to an altered protein (F508del-CFTR) folding with a nascent protein retained within the ER and is quickly degraded. We previously showed that AnxA5 binds to F508del-CFTR and that its increased expression due to a Gonadoliberin (GnRH) augments Cl- efflux in cells expressing F508del-CFTR. The aim of the present work was to use the GnRH analog buserelin which is already used in medicine. Human nasal epithelial cells from controls and CF patients (F508del/F508del) were treated with buserelin and we show here that the treatment alleviates Cl- channel defects in CF cells. Using proteomics we highlighted some proteins explaining this result. Finally, we propose that buserelin is a potential new pharmaceutical compound that can be used in CF and that bronchus can be targeted since we show here that they express GnRH-R.

Characterization and Expression Pattern Analysis of the T-Complex Protein-1 Zeta Subunit in Musca domestica L (Diptera)

Chaperonins, belonging to the T-complex protein-1 (TCP-1) family, assist in the correct folding of nascent and misfolded proteins. It is well-known that in mammals, the zeta subunit of the TCP-1 complex (TCP-1ζ) plays a vital role in the folding and assembly of cytoskeleta proteins. This study reported for the first time the cloning, characterization and expression pattern analysis of the TCP-1ζ from Musca domestica, which was named as MdTCP-1ζ. The MdTCP-1ζ cDNA is 1,803 bp long with a 1,596 bp open reading frame that encodes a protein with 531 bp amino acids. The analysis of the transcriptional profile of MdTCP-1ζ using qRT-PCR revealed relatively high expression in the salivary glands and trachea at the tissues while among the developmental stages. The highest expression was observed only in the eggs suggesting that the MdTCP-1ζ may play a role in embryonic development. The expression of MdTCP-1ζ was also significantly induced after exposure to short-term heat shock and infection by Escherichia coli, Staphylococcus aureus, or Candida albicans. This suggested that MdTCP-1ζ may take part in the immune responses of housefly and perhaps contribute to the protection against cellular injury.

Identification and Genetic Effect of Haplotypes in the Distal Promoter Region of Chicken CCT6A Gene Associated with Egg Production Traits

The chaperonin containing TCP-1 complex protein 1 subunit zeta (CCT6A) is the only cytosolic chaperonin in eukaryotes assisting in the folding of cytoplasmic proteins. Previous study revealed that the mRNA expression of chicken CCT6A gene was remarkably elevated in the sexually mature ovaries. However, the mechanism underlying chicken CCT6A expression changes remains largely unknown. In this study, haplotypes caused by two single nucleotide polymorphisms (SNPs) of chicken CCT6A gene promoter (g.−2215 T>C and g.−1959 T>C) were identified and their associations with egg production traits as well as effects on gene expression were analyzed. Altogether four haplotypes including A (C⁻²²¹⁵-T⁻¹⁹⁵⁹), B (C⁻²²¹⁵-C⁻¹⁹⁵⁹), C (T⁻²²¹⁵-T⁻¹⁹⁵⁹) and D (T⁻²²¹⁵-C⁻¹⁹⁵⁹) were detected in all of the five chicken populations. Diplotypes AA, AD and DD were predominant in Xinyang brown hens, among which diplotype AD was associated with higher egg number at the age of 28 weeks old (E28) (P<0.05). In addition, diplotype AD was also predominant in Xinyang brown and Hy-line brown chicken populations with high egg production; whereas in Wenchang and Shouguang chicken populations which are Chinese indigenous chicken breeds and relatively lower in egg production, diplotype AA was predominant. Compared with diplotypes AA and DD, the mRNA expression of CCT6A in diplotype AD birds is the highest in F1, F5, and POF1 follicles of Hy-line brown hens (P<0.05). These results suggest that the two SNPs in chicken CCT6A promoter region are potential DNA marker for improving egg production trait.

Protective Effects of Scutellarin on Human Cardiac Microvascular Endothelial Cells against Hypoxia-Reoxygenation Injury and Its Possible Target-Related Proteins

Scutellarin (SCU) is one of the main components of traditional Chinese medicine plant Erigeron breviscapus (Vant.) Hand.-Mazz. In this paper, we studied the protective effects of SCU on human cardiac microvascular endothelial cells (HCMECs) against hypoxia-reoxygenation (HR) injury and its possible target-related proteins. Results of MTT assay showed that pretreatment of SCU at doses of 1, 5, and 10 μM for 2 h could significantly inhibit the decrease in cell viability of HCMECs induced by HR injury. Subcellular fractions of cells treated with vehicle control, 1 μM SCU, HR injury, or 1 μM SCU + HR injury were separated by ultracentrifugation. The protein expression profiles of cytoplasm and membrane/nuclei fractions were checked using protein two-dimensional electrophoresis (2-DE). Proteins differentially expressed between control and SCU-treated group, control and HR group, or HR and SCU + HR group were identified using mass spectrometry (MS/MS). Possible interaction network of these target-related proteins was predicted using bioinformatic analysis. The influence of SCU on the expression levels of these proteins was confirmed using Western blotting assay. The results indicated that proteins such as p27BBP protein (EIF6), heat shock 60 kDa protein 1 (HSPD1), and chaperonin containing TCP1 subunit 6A isoform (CCT6A) might play important roles in the effects of SCU.

Progesterone regulates chicken embryonic germ cell meiotic initiation independent of retinoic acid signaling

The signaling molecule retinoic acid (RA) is known to trigger germ cells to enter meiosis. However, RA may not be the only secreted inducer of meiosis. Our previous data indicate that luteinizing hormone also promotes germ cell meiotic initiation by upregulating 3βHSDII transcription. Here, using chicken embryos, we investigate the role of progesterone (P4) in regulating germ cell meiotic initiation. Progesterone treatment at embryonic Day 9.5 accelerated germ cell meiosis entry in the female chicken embryos. However, P4 treatment in vivo did no influence on testicular germ cells but triggered their meiotic initiation in the cultured testes. As treatment with an RA receptor (RAR) inhibitor did not block the stimulatory effect of P4 on germ cell meiotic initiation, this P4 stimulatory effect seems to be independent of RAR-mediated signaling. The abundance of RA metabolism-related enzymes and RAR (RARβ) mRNAs did not differ significantly between P4-treated and control individuals. The RA concentration in the ovaries remained unchanged by P4 treatment in vivo. Because no inhibition by the P4 receptor (PR) nuclear receptor antagonist mifepristone on P4 effect was observed in either in vitro or in vivo experiments, the effect of P4 on germ cell meiotic initiation is probably mediated by membrane PRs (mPR). The mPRα, mPRβ, and mPRγ mRNAs were all expressed in the embryonic ovaries. The expression of mPRα and mPRβ was higher than that of mPRγ. Immunohistochemical results showed that mPRα-positive cells were mainly scattered in the ovarian cortex area where most germ cells were distributed. The mPRβ-positive cells were widely distributed in the ovaries, and positive cells were clustered with a similar morphology to that of germ cell clusters. In conclusion, P4 may regulate embryonic germ cell meiotic initiation independent of RA signaling through the membrane PRs. This study provides a new insight into the mechanisms of germ cell meiotic initiation in the chicken.

Rapid impact of progesterone on the neuronal growth cone

In the last two decades, sensory neurons and Schwann cells in the dorsal root ganglia (DRG) were shown to express the rate-limiting enzyme of the steroid synthesis, cytochrome P450 side-chain cleavage enzyme (P450scc), as well as the key enzyme of progesterone synthesis, 3β-hydroxysteroid dehydrogenase (3β-HSD). Thus, it was well justified to consider that DRG neurons similarly are able to synthesize progesterone de novo from cholesterol. Because direct progesterone effects on axonal outgrowth in peripheral neurons have not been investigated up to now, the present study provides the first insights into the impact of exogenous progesterone on axonal outgrowth in DRG neurons. Our studies including microinjection and laser scanning microscopy demonstrate morphological changes especially in the neuronal growth cones after progesterone treatment. Furthermore, we were able to detect a distinctly enhanced motility only a few minutes after the start of progesterone treatment using time-lapse imaging. Investigation of the cytoskeletal distribution in the neuronal growth cone before, during, and after progesterone incubation revealed a rapid reorganization of actin filaments. To get a closer idea of the underlying receptor mechanisms, we further studied the expression of progesterone receptors in DRG neurons using RT-PCR and immunohistochemistry. Thus, we could demonstrate for the first time that classical progesterone receptor (PR) A and B and the recently described progesterone receptor membrane component 1 (PGRMC1) are expressed in DRG neurons. Antagonism of the classical progesterone receptors by mifepristone revealed that the observed progesterone effects are transmitted through PR-A and PR-B.