Identification of Differentially Expressed Gene Transcripts in Porcine Endometrium during Early Stages of Pregnancy

Abstract

During the early stages of pregnancy, the uterine endometrium undergoes dramatic morphologic and functional changes accompanied with dynamic variation in gene expression. Pregnancy-stage specific differentially expressed gene (DEG)-transcript-probes were investigated and identified by comparing endometrium transcriptome at 9th day (9D), 12th day (12D) and 16th day (16D) of early pregnancy in Polish large-white (PLW) gilts. Endometrium comparisons between 9D-vs-12D, 9D-vs-16D and 12D-vs-16D of early pregnancy identified 6049, 374 and 6034 highly significant DEG-transcript-probes (p < 0.001; >2 FC). GO term enrichment analysis identified commonly shared upregulated endometrial DEG-transcript-probes (p < 0.001; >2 FC), that were regulating the gene functions of anatomic structure development and transport (TG), DNA-binding and methyltransferase activity (ZBTB2), ion-binding and kinase activity (CKM), cell proliferation and apoptosis activity (IL1B). Downregulated DEG-transcript-probes (p < 0.001; >2 FC) were involved in regulating the gene functions of phosphatase activity (PTPN11), TC616413 gene-transcript and Sus-scrofa LOC100525539. Moreover, blastn comparison of microarray-probes sequences against sus-scrofa11 assembly identified commonly shared upregulated endometrial DEG-transcript-probes (E < 0.06; >2 FC), that were regulating the gene functions of reproduction and growth (SELENOP), cytoskeleton organization and kinase activity (CDC42BPA), phosphatase activity (MINPP1), enzyme-binding and cell-population proliferation (VAV3), cancer-susceptibility candidate gene (CASC4), cytoskeletal protein-binding (COBLL1), ion-binding, enzyme regulator activity (ACAP2) Downregulated endometrial DEG-transcript-probes (E < 0.06; >2FC) were involved in regulating the gene functions of signal-transduction (TMEM33), catabolic and metabolic processes (KLHL15). Microarray validation experiment on selected candidate genes showed complementarity to significant endometrial DEG-transcript-probes responsible for the regulation of immune response (IL1B, S100A11), lipid metabolism (FABP3, PPARG), cell-adhesion (ITGAV), angiogenesis (IL1B), intercellular transmission (NMB), cell-adhesion (OPN) and response to stimuli (RBP4) was confirmed by RT-PCR. This study provides a clue that identified pregnancy-stage specific microarray transcript probes could be considered as candidate genes for recognition and establishment of early pregnancy in the pig.

Integrating LCM-Based Spatio-Temporal Transcriptomics Uncovers Conceptus and Endometrial Luminal Epithelium Communication that Coordinates the Conceptus Attachment in Pigs

“…The gene-specific primers are listed in Table S7 . The GAPDH gene was used as a control [ 80 ]. Wilcoxon’s test was performed using R, and p -values < 0.05 were considered statistically significant.…”

“…PCR conditions were as follows: a single cycle of 30 s at 95 • C, followed by 39 cycles of 5 s at 95 • C and 30 s at 60 • C. The gene-specific primers are listed in Table S7. The GAPDH gene was used as a control [80]. Wilcoxon's test was performed using R, and p-values < 0.05 were considered statistically significant.…”

Molecular Characterisation of Uterine Endometrial Proteins during Early Stages of Pregnancy in Pigs by MALDI TOF/TOF

“…The present paper hypothesized that during the peri-implantation period, the dynamic proteome alterations in the uterine fluid could be visible between the 10D and 14D of pregnancy [7,8]. In the first few weeks of pregnancy in the pig, these critical alterations could be defined as the preimplantation period after fertilisation, that is, early pregnancy before maternal recognition of pregnancy (gestation period duration of 1-10 days: in this study the 9D); the peri-implantation period of maternal recognition of pregnancy (gestation period duration of 11-13 days: in this study the 12D) and, the peri-implantation period to determine establishment or failure of pregnancy (gestation period duration of 14-19 days: in this study the 16D) [3]. The proteome profile of the endometrium remains in a close relationship with the uterus condition during the embryo implantation process [9].…”

“…The endometrium layers experience functional cyclical changes regulated by ovarian hormones, growth factors, and cytokines [1]. In recent studies, physiological and molecular examinations of the uterine endometrium during the peri-implantation period have revealed several genes associated with signalling pathways involved in embryo-uterine crosstalk to be differentially expressed [2][3][4][5][6],. The present paper hypothesized that during the peri-implantation period, the dynamic proteome alterations in the uterine fluid could be visible between the 10D and 14D of pregnancy [7,8].…”

“…Besides progesterone (P4) produced by the corpus luteum, estradiol derived from the embryo is also required that stimulates maternal recognition of pregnancy and, also for early pregnancy maintenance [11]. In the pig, at least four fully functional embryos must be present to sustain multifetal pregnancy [3]. The estimated mortality rate of the embryo in the peri-implantation period in swine is about 20-30%, which means that every third fertilised oocyte degenerates before day 35 of pregnancy.…”