Transcription profiling of porcine endometrium from chronological stages of psuedopregnancy and estrogen disrupted psuedopregnancy
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ABSTRACT: Placentation of the conceptus to the surface epithelium is governed through a tightly regulated temporal and spatial window. Premature exogenous steriod exposure causes a shift in the maternal tissue's receptivity and prevents proper placentation. We used Affymetrix microarrays to detail the aberrant changes in uterine gene expression during this window, while removing all conceptus contribution to this dysfunction. Experiment Overall Design: Porcine endometrium was selected at chronological stages of psuedopregnancy and psuedopregnancy post endocrine disrupted early for RNA extraction and hybridization on Affymetrix microarrays. We sought to obtain homogeneous populations of normal endometrium at days 13 and 15 of the pseudo pregnant, and endometrium at days 13 and 15 of the endocrine disrupted pseudo pregnant in order to identify the temporal resolution of expression profiles. In brief, days 13 through 15 accounts for the window of attachment during pregnancy in the pig, so we created pseudo pregnant endometrium and obtained samples from days 13 (PIG13UN_TX)and 15 (PIG15UN_TX) of pseudo pregnancy. In the same, we created pseudo pregnant endometrium that was subjected to endocrine disruption of the pseudo pregnancy and collected samples on days 13 (PIG13_TX)and 15 (PIG15_TX) of pseudo pregnancy.
Project description:The porcine conceptus undergoes rapid differentiation and expansion of its trophoblastic membranes between Days 11 and 12 of gestation. Concomitant with trophoblast elongation, production of conceptus estrogen, the porcine embryonic pregnancy recognition signal increases. Conceptus attachment to the uterine surface epithelium starts after Day 13 initiating epitheliochorial placentation. To analyze the transcriptome changes in the endometrium in the course of maternal recognition of pregnancy (MRP), deep sequencing of endometrial RNA samples of Day 12 pregnant animals (n=4) and corresponding non-pregnant controls (n=4) was performed using Illumina RNA-Seq. Between 30 and 35 million sequence reads per sample were produced and mapped to the porcine genome (Sscrofa10.2). Analysis of read counts revealed 2,593 differentially expressed genes (DEG). Expression of selected genes was validated by the use of quantitative real-time RT-PCR. Bioinformatics analysis identified several functional terms specifically overrepresented for up-regulated or down-regulated genes. Comparison of the RNA-Seq data from Days 12 and 14 of pregnancy was performed at the level of all expressed genes, of the DEG, and at the level of functional categories. This revealed specific gene expression patterns, reflecting the different functions of the endometrium during these stages, i.e. recognition of pregnancy and preparation for conceptus attachment. Genes related to mitosis, immune response, epithelial cell differentiation and development, proteolysis, and prostaglandin signaling and metabolism are discussed in detail. In conclusion, this study identified comprehensive transcriptome changes in porcine endometrium associated with MRP and initiation of implantation and a number of genes and pathways potentially involved in regulation of these processes. In total, 8 samples were analyzed, 4 biological replicates for pregnant animals (samples from 4 different animals) and 4 biological replicates for cyclic controls (samples from 4 different animals)
Project description:In pigs, conceptus attachment to the uterine surface epithelium starts around day 14 of pregnancy preceded by a pronounced vascularization at the implantation zones, initiating the epitheliochorial placentation. To characterize the complex transcriptome changes in the endometrium in the course of initial conceptus attachment deep sequencing of endometrial RNA samples of pregnant animals (n=4) and corresponding cyclic controls (n=4) was performed using Illumina RNA-Seq. The obtained sequence reads were mapped to the porcine genome and relative expression values were calculated for the analysis of differential gene expression. Statistical analysis revealed 1,933 differentially expressed genes (FDR 1%), 1,229 with higher and 704 with lower mRNA concentration in the samples from pregnant animals. Expression of selected genes was validated by the use of quantitative real-time RT-PCR. The RNA-Seq data were compared to results of a microarray study of bovine endometrium on day 18 of pregnancy and additional related data sets. Bioinformatics analysis revealed for the genes with higher mRNA concentration in pregnant samples strong overrepresentation particularly for immune-related functional terms but also for apoptosis and cell adhesion. Overrepresented terms for the genes with lower mRNA concentration in pregnant samples were related to extracellular region, ion transport, cell adhesion and lipid and steroid metabolic process. In conclusion, RNA-Seq analysis revealed comprehensive transcriptome differences in porcine endometrium between day 14 of pregnancy and corresponding cyclic endometrium and highlighted new processes and pathways probably involved in regulation of non-invasive implantation in the pig. In total, 8 samples were analyzed, 4 biological replicates for pregnant animals (samples from 4 different animals) and 4 biological replicates for cyclic controls (samples from 4 different animals)
Project description:Endometrial receptivity plays a vital role in the success of embryo implantation. However, the temporal proteomic profile of porcine endometrium during embryo implantation is still unclear. In this study, the expression of proteins in endometrium on days 9, 10, 11, 12, 13, 14, 15 and 18 of pregnancy (D9, 10, 11, 12, 13, 14, 15 and 18) was profiled via iTRAQ technology. The results showed that 25, 55, 103, 91, 100, 120, 149 proteins were up-regulated, and 24, 70, 169, 159, 164, 161, 198 proteins were down-regulated in porcine endometrium on D10, 11, 12, 13, 14, 15 and 18 compared with that on D9, respectively. Among these differentially expressed (DE) proteins, MQM results indicated that S100A9, S100A12, HRG and IFI6 were differentially expressed in endometrial tissues during embryo implantation period. Bioinformatics analysis showed that the proteins differentially expressed in the 8 comparisons (D10 vs D9, D11 vs D9, D12 vs D9, D13 vs D9, D14 vs D9, D15 vs D9 and D18 vs D9) were involved in important processes and pathways related to immunization, endometrial remodeling, which have a vital effect on embryonic implantation. Our results reveal that RBP4 could regulate the cell proliferation, migration and apoptosis of endometrial epithelial cells and endometrial stromal cells to affect embryo implantation. This research also provides resources for studies of proteins in endometrium during early pregnancy.
Project description:In an attempt to unveil part of the molecular processes controlling porcine placentation we have investigated the pregnancy induced gene expression in the porcine endometrium at Day 14 after insemination using the Affymetrix GeneChip® Porcine Genome Array. Experiment Overall Design: At Day 14 after insemination, samples were obtained from the endometrium of pregnant sows and sows inseminated with inactivated semen for RNA extraction and hybridization on Affymetrix microarrays. The uteri were removed and each uterine horn was flushed with PBS containing 1% fetal calf serum, and subsequently opened longitudinally at the anti-mesometrial side. The sites of embryonic attachment were macroscopically visual in the endometrium on the mesometrial side in form of hyperemic zones. Samples of the endometrium (lamina epithelialis, lamina propria and tela submucosa, but not tunica muscularis) were isolated from proximal (the end close to the ovaries), intermedial, and distal (next to the corpus uteri)) sections of each uterine horn. Samples were taken from the endometrium of the non-pregnant animals at comparable locations.
Project description:Successful placentation requires delicate communication between endometrium and trophoblasts. The invasion and integration of trophoblasts into the endometrium during early pregnancy is crucial to placentation. Dysregulation of these functions is associated with various pregnancy complications such as miscarriage and preeclampsia. The endometrial microenvironment exerts an important influence on trophoblast cell functions. We hypothesized that the hormonal environment regulates the miRNA profile and secretome of the human endometrial gland, which subsequently modulates trophoblast functions during early pregnancy. By establishing the first secretome profiles and miRNA atlas of these endometrial organoids to the hormonal changes followed by trophoblast functional assays, we demonstrated that sex steroid hormones modulate aquaporins (AQP)1/9 and S100A9 secretions through miR-3194 activation in endometrial epithelial cells, which in turn enhanced trophoblast migration and invasion during early pregnancy.
Project description:BACKGROUND: Litter size in pigs is a major factor affecting the profitability in the pig industry. The peri-implantation window in pigs is characterized by the coordinated interactions between the maternal uterine endometrium and the rapidly elongating conceptuses and represents a period of time during which a large percentage of the developing conceptuses are lost. However, the gene expression and regulatory networks in the endometrium contributing to the establishment of the maternal: placental interface remain poorly understood. RESULTS: We characterized the endometrial gene expression profile during the peri-implantation stage of development by comparing two breeds that demonstrate very different reproductive efficiencies. We employed the porcine Affymetrix GeneChip® to assay the transcriptomic profiles of genes expressed in the uterine endometrium obtained from Meishan and Yorkshire gilts (n = 4 for each breed) on day 12 of gestation (M12 and Y12, respectively). Total of 17,076 probesets were identified as "present" in at least two arrays. A mixed model-based statistical analysis predicted a total of 2,656 (q < 0.1) transcripts as differentially expressed between Meishan and Yorkshire pigs. Eighteen differentially expressed transcripts of interest were validated by quantitative real-time PCR. Gene ontology (GO) annotation revealed that the known functions of the differentially expressed genes were involved in a series of important biological processes relevant to early pregnancy establishment in the pig. CONCLUSIONS: The results identified endometrial gene expression profiles of two breeds differing in litter size and identified candidate genes that are related to known physiological pathways related to reproductive prolificacy. These findings provide a deeper understanding of molecular pathways differing between two breeds at the critical peri-implantation stage of pregnancy, which can be utilized to better understand the events contributing to pregnancy establishment in the pig. Meishan and Yorkshire breeds endometirum were selected and RNA been extracted and hybridized to the Affymetrix microarray. A number of genes have been shown differently expressed on two breeds.
Project description:Recently, microRNAs (miRNAs), known to modulate gene expression through post-transcriptional mechanisms, were implied in regulation of early pregnancy events including maternal recognition of pregnancy and implantation. To characterize complex transcriptomic changes in expression of miRNAs in pregnant and cyclic endometria collected on days 12, 16 and 20 was analyzed using Illumina deep sequencing. This research showed repertoire of pregnancy-related miRNAs in porcine endometrium during initial stages of conceptus implantation and during the estrous cycle and sheds light on miRNA-mediated gene expression regulation mechanism at the maternal-conceptus interface. miRNAs and isomiRs expression profiles were analyzed in samples collected from porcine endometrium on Days 12, 16 and 20 of pregnancy and estrous cycle. Each group was represented by 4 to 6 samples. Generated libraries were run in multiplex using specific barcodes to differentiate samples. Illumina sequencing was performed in duplicate (two runs) and after demultiplexing, the same samples from two independent runs were concatenated.
Project description:The female reproductive tract provides a unique environment for a successful pregnancy. It is imperative that the non-pregnant uterus be transformed into a capable environment for the establishment and maintenance of pregnancy. To achieve this, intimate cross-communication between the endometrium and the embryo is necessary at an early stage of life (Almiñana et al., 2012) a dialog which further influences subsequent fetal developmental potential (Fleming et al., 2004) and even post-natal performance. Initially, the trophoblast-derived estrogen is one of the most important embryonic signals to activate the maternal uterus for attachment (Pope & First 1985). Once the conceptus has established its position in the uterus (>d15), its development and growth also require many other maternal-embryonic cellular and molecular interactions to ensure substantial vascular changes in the endometrium and the chorioallantois, mainly development of capillaries under the lamina propriae, essential to provide full function to the pig epiteliochorial placenta required for a successful pregnancy. It is during the peri-attachment window between days 12-30 of gestation when most (20-30%) of the embryos produced in pig natural or artificial breeding die (reviewed by Edwards et al., 2012); embryonic death with a substantial impact on pig production efficiency, especially because it significantly limits litter size. Different studies have focused on the elucidation of the complex embryo-maternal communication network to reduce pregnancy loss. Among these, several studies examined gene expression during the peri-implantation stage, when the majority of embryonic losses occur, or have compared the transcriptomic profiles of pregnant and non- pregnant animals. Interestingly, these studies identified changes in the expression of genes that can -directly or indirectly- contribute to reproductive success such genes related to cell proliferation, hormone synthesis and metabolism, cell adhesion or those related to cytokine production and immune local response (Almiñana et al., 2012, Lin et al, 2015; Smolinska et al., 2019; Yang et al., 2020, Martinez et al., 2020, 2022). However, we should not forget that changes in gene expression do not always lead to a corresponding alteration in the expression of proteins, which are crucial components in all biological processes. The knowledge of the proteome is therefore equally relevant to gene expression changes, being able to help detecting both normal and abnormal physiological conditions. Proteome characterization can led to a better understanding of physiological processes and to identify proteins that may serve as potential biomarkers. To date, only a limited number of studies have unfortunately explored the protein expression profiles of the pig endometrium during the crucial period of maternal recognition of pregnancy, which occurs between day 9 and 13 (Jalali et al., 2015; Kaiser et al., 2006) or during mid/last-gestation, from 40 to 93 days of pregnancy (Chae et al., 2011; Wang et al., 2019). These studies have identified several proteins associated with endometrial function, which could play a role in maternal recognition and progression of pregnancy. Therefore, in order to fully understand the molecular interaction between the conceptus and its chorion with the endometrium, we have aimed to characterize the proteome profile of both, the non-pregnant (control) endometrium compared with that of the “pregnant”endometrium with present extraembryonic membranes between the 3rd and the 4th week period, when the major conceptus loss occurs.
Project description:In pigs, conceptus attachment to the uterine surface epithelium starts around day 14 of pregnancy preceded by a pronounced vascularization at the implantation zones, initiating the epitheliochorial placentation. To characterize the complex transcriptome changes in the endometrium in the course of initial conceptus attachment deep sequencing of endometrial RNA samples of pregnant animals (n=4) and corresponding cyclic controls (n=4) was performed using Illumina RNA-Seq. The obtained sequence reads were mapped to the porcine genome and relative expression values were calculated for the analysis of differential gene expression. Statistical analysis revealed 1,933 differentially expressed genes (FDR 1%), 1,229 with higher and 704 with lower mRNA concentration in the samples from pregnant animals. Expression of selected genes was validated by the use of quantitative real-time RT-PCR. The RNA-Seq data were compared to results of a microarray study of bovine endometrium on day 18 of pregnancy and additional related data sets. Bioinformatics analysis revealed for the genes with higher mRNA concentration in pregnant samples strong overrepresentation particularly for immune-related functional terms but also for apoptosis and cell adhesion. Overrepresented terms for the genes with lower mRNA concentration in pregnant samples were related to extracellular region, ion transport, cell adhesion and lipid and steroid metabolic process. In conclusion, RNA-Seq analysis revealed comprehensive transcriptome differences in porcine endometrium between day 14 of pregnancy and corresponding cyclic endometrium and highlighted new processes and pathways probably involved in regulation of non-invasive implantation in the pig.
Project description:The porcine conceptus undergoes rapid differentiation and expansion of its trophoblastic membranes between Days 11 and 12 of gestation. Concomitant with trophoblast elongation, production of conceptus estrogen, the porcine embryonic pregnancy recognition signal increases. Conceptus attachment to the uterine surface epithelium starts after Day 13 initiating epitheliochorial placentation. To analyze the transcriptome changes in the endometrium in the course of maternal recognition of pregnancy (MRP), deep sequencing of endometrial RNA samples of Day 12 pregnant animals (n=4) and corresponding non-pregnant controls (n=4) was performed using Illumina RNA-Seq. Between 30 and 35 million sequence reads per sample were produced and mapped to the porcine genome (Sscrofa10.2). Analysis of read counts revealed 2,593 differentially expressed genes (DEG). Expression of selected genes was validated by the use of quantitative real-time RT-PCR. Bioinformatics analysis identified several functional terms specifically overrepresented for up-regulated or down-regulated genes. Comparison of the RNA-Seq data from Days 12 and 14 of pregnancy was performed at the level of all expressed genes, of the DEG, and at the level of functional categories. This revealed specific gene expression patterns, reflecting the different functions of the endometrium during these stages, i.e. recognition of pregnancy and preparation for conceptus attachment. Genes related to mitosis, immune response, epithelial cell differentiation and development, proteolysis, and prostaglandin signaling and metabolism are discussed in detail. In conclusion, this study identified comprehensive transcriptome changes in porcine endometrium associated with MRP and initiation of implantation and a number of genes and pathways potentially involved in regulation of these processes.