Transcriptional profiling of equine conceptuses reveals new aspects of embryo-maternal communication in the horse.
Abstract: Establishment and maintenance of pregnancy are critically dependent on embryo-maternal communication during the preimplantation period. The horse is one of the few domestic species in which the conceptus-derived pregnancy recognition signal has not been identified. To gain new insights into the factors released by the equine conceptus, transcriptional profiling analyses of conceptuses retrieved 8, 10, 12, and 14 days after ovulation were performed using a whole-genome microarray. Selected array data were confirmed using quantitative PCR, and the expression of proteins of interest was confirmed using immunohistochemistry and Western blotting. Gene ontology classification of differentially regulated transcripts underlines the ongoing embryo-maternal dialogue. Transcript showing higher expression levels as conceptus' development proceeds mainly localizes to the extracellular environment, thereby having the potential to act upon the uterine environment. Genes involved in the positive regulation of the immune system are enriched among transcripts displaying decreased expression, reflecting the need of the semiallograft conceptus to be protected from the immune system. A subset of differentially expressed genes, such as BRCA1 and FGF2, has previously been described to be expressed by early stages of embryonic development, whereas other transcripts are apparently unique to equine conceptuses, as their expression has not been reported in other species. These transcripts include fibrinogen subunits, the expressions of which were confirmed at the mRNA and protein level. Furthermore, results indicate the counteraction of trophoblast invasion, and that the conceptus appears to regulate changes in sialic acid content of its capsule, an event suggested to be essential for successful establishment of pregnancy.
Publication Date: 2011-01-05 PubMed ID: 21209420DOI: 10.1095/biolreprod.110.088732Google Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
- Validation Study
Summary
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The research article investigates the process of embryo-maternal communication in horses, during the preimplantation period of pregnancy, by conducting transcriptional profiling analyses. The researchers analyze the various transcripts and proteins expressed by the developing equine conceptus, revealing new insights into how the horse embryo may signal pregnancy recognition and interact with the uterine environment.
Methodology
- The study performed transcriptional profiling analyses on equine conceptuses, or embryos, obtained 8, 10, 12, and 14 days after ovulation. This was done using a whole-genome microarray, a chip that carries an array of sequences representing the genome.
- Selected data from the array were then confirmed through quantitative PCR, a method that measures the amount of a specific RNA.
- Immunohistochemistry and Western blotting were also used to investigate the expression of certain proteins of interest.
Findings
- The gene ontology classification, which groups genes based on their shared biological characteristics, highlighted the ongoing dialogue between the embryo and the mother. This largely happens through genes that express more as the embryo develops, particularly those located in the extracellular environment. These genes can potentially impact the uterine environment.
- The study found that genes responsible for positively regulating the immune system were enriched among the transcripts that exhibited decreased expression levels. This reflects the need for the embryo, which is technically a semiallograft, to protect itself from the mother’s immune system.
- A subset of the differentially expressed genes, including BRCA1 and FGF2, have been previously identified in early stages of embryonic development in other studies. But there are still other transcripts unique to horse embryos, such as fibrinogen subunits, whose expressions were confirmed at both the mRNA and protein level in this study.
Implications
- The study’s findings indicate that the conceptus, or early embryo, counters the invasion of the trophoblast, the outer layer of the embryo that provides nutrients from the mother to the fetus and develops into a large part of the placenta.
- The research suggests that the conceptus regulates changes in its capsule’s sialic acid content—an event considered essential for the successful establishment of pregnancy. This insight could be critical for further investigations into equine reproduction biology.
Cite This Article
APA
Klein C, Troedsson MH.
(2011).
Transcriptional profiling of equine conceptuses reveals new aspects of embryo-maternal communication in the horse.
Biol Reprod, 84(5), 872-885.
https://doi.org/10.1095/biolreprod.110.088732 Publication
Researcher Affiliations
- Gluck Equine Research Center, Department of Veterinary Science, University of Kentucky, Lexington, KY 40546, USA. claudia.klein@uky.edu
MeSH Terms
- Animals
- BRCA1 Protein / genetics
- BRCA1 Protein / metabolism
- Blastocyst / metabolism
- DNA Probes
- Embryonic Development
- Extraembryonic Membranes / cytology
- Extraembryonic Membranes / metabolism
- Female
- Fibrinogen / genetics
- Fibrinogen / metabolism
- Fibroblast Growth Factor 2 / genetics
- Fibroblast Growth Factor 2 / metabolism
- Gene Expression Profiling
- Gene Expression Regulation, Developmental
- Horses / embryology
- Horses / genetics
- Horses / metabolism
- Immune System / embryology
- Immunohistochemistry
- Male
- Maternal-Fetal Exchange
- N-Acetylneuraminic Acid / metabolism
- Polymerase Chain Reaction
- Pregnancy
- RNA, Messenger / metabolism
- Trophoblasts / metabolism
Citations
This article has been cited 22 times.- Haslin E, Pettigrew EJ, Hickson RE, Kenyon PR, Gedye KR, Lopez-Villalobos N, Jayawardana JMDR, Morris ST, Blair HT. Genome-Wide Association Studies of Live Weight at First Breeding at Eight Months of Age and Pregnancy Status of Ewe Lambs.. Genes (Basel) 2023 Mar 27;14(4).
- Vegas AR, Podico G, Canisso IF, Bollwein H, Fröhlich T, Bauersachs S, Almiñana C. Dynamic regulation of the transcriptome and proteome of the equine embryo during maternal recognition of pregnancy.. FASEB Bioadv 2022 Dec;4(12):775-797.
- Gibson C, de Ruijter-Villani M, Stout TAE. Insulin-like growth factor system components expressed at the conceptus-maternal interface during the establishment of equine pregnancy.. Front Vet Sci 2022;9:912721.
- Rudolf Vegas A, Hamdi M, Podico G, Bollwein H, Fröhlich T, Canisso IF, Bauersachs S, Almiñana C. Uterine extracellular vesicles as multi-signal messengers during maternal recognition of pregnancy in the mare.. Sci Rep 2022 Sep 16;12(1):15616.
- Perera TRW, Skerrett-Byrne DA, Gibb Z, Nixon B, Swegen A. The Future of Biomarkers in Veterinary Medicine: Emerging Approaches and Associated Challenges.. Animals (Basel) 2022 Aug 26;12(17).
- Shen Y, Ren H, Davshilt T, Tian S, Wang X, Yi M, Ulaangerel T, Li B, Dugarjav M, Bou G. The transcriptome landscapes of allantochorion and vitelline-chorion in equine day 30 conceptus.. Front Cell Dev Biol 2022;10:958205.
- Lawson EF, Grupen CG, Baker MA, Aitken RJ, Swegen A, Pollard CL, Gibb Z. Conception and early pregnancy in the mare: lipidomics the unexplored frontier.. Reprod Fertil 2022 Jan 1;3(1):R1-R18.
- Rivera Del Alamo MM, Reilas T, Lukasik K, Galvão AM, Yeste M, Katila T. Inflammatory Markers in Uterine Lavage Fluids of Pregnant, Non-Pregnant, and Intrauterine Device Implanted Mares on Days 10 and 15 Post Ovulation.. Animals (Basel) 2021 Dec 8;11(12).
- Klein C, Bruce P, Hammermueller J, Hayes T, Lillie B, Betteridge K. Transcriptional profiling of equine endometrium before, during and after capsule disintegration during normal pregnancy and after oxytocin-induced luteostasis in non-pregnant mares.. PLoS One 2021;16(10):e0257161.
- Swegen A. Maternal recognition of pregnancy in the mare: does it exist and why do we care?. Reproduction 2021 May 5;161(6):R139-R155.
- Camacho CA, Santos GO, Caballeros JE, Cazales N, Ramirez CJ, Vidigal PMP, Ramos HJO, Barros E, Mattos RC. Uterine infusion of conceptus fragments changes the protein profile from cyclic mares.. Anim Reprod 2020 Nov 25;17(4):e20200552.
- Martí A, Serrano A, Pastor J, Rigau T, Petkevičiuté U, Calvo MÀ, Arosemena EL, Yuste A, Prandi D, Aguilar A, Rivera Del Alamo MM. Endometrial Status in Queens Evaluated by Histopathology Findings and Two Cytological Techniques: Low-Volume Uterine Lavage and Uterine Swabbing.. Animals (Basel) 2021 Jan 5;11(1).
- Camacho CA, Estradé MJ, Cazales N, Caballeros JE, Fiala-Rechsteiner SM, Neves AP, Mattos RC. Histomorphometric and vascular changes in equine endometrium after the infusion of conceptus fragments.. Anim Reprod 2020 Jun 29;17(2):e20200006.
- Gibson C, de Ruijter-Villani M, Bauersachs S, Stout TAE. Asynchronous Embryo Transfer Followed by Comparative Transcriptomic Analysis of Conceptus Membranes and Endometrium Identifies Processes Important to the Establishment of Equine Pregnancy.. Int J Mol Sci 2020 Apr 7;21(7).
- Smits K, Gansemans Y, Tilleman L, Van Nieuwerburgh F, Van De Velde M, Gerits I, Ververs C, Roels K, Govaere J, Peelman L, Deforce D, Van Soom A. Maternal Recognition of Pregnancy in the Horse: Are MicroRNAs the Secret Messengers?. Int J Mol Sci 2020 Jan 9;21(2).
- Read JE, Cabrera-Sharp V, Offord V, Mirczuk SM, Allen SP, Fowkes RC, de Mestre AM. Dynamic changes in gene expression and signalling during trophoblast development in the horse.. Reproduction 2018 Oct 1;156(4):313–330.
- Read JE, Cabrera-Sharp V, Offord V, Mirczuk SM, Allen SP, Fowkes RC, de Mestre AM. Dynamic changes in gene expression and signalling during trophoblast development in the horse.. Reproduction 2018 Oct 1;156(4):313-330.
- Smits K, Willems S, Van Steendam K, Van De Velde M, De Lange V, Ververs C, Roels K, Govaere J, Van Nieuwerburgh F, Peelman L, Deforce D, Van Soom A. Proteins involved in embryo-maternal interaction around the signalling of maternal recognition of pregnancy in the horse.. Sci Rep 2018 Mar 27;8(1):5249.
- Aurich C, Budik S. Early pregnancy in the horse revisited - does exception prove the rule?. J Anim Sci Biotechnol 2015;6:50.
- Tachibana Y, Sakurai T, Bai H, Shiota K, Nambo Y, Nagaoka K, Imakawa K. RNA-seq analysis of equine conceptus transcripts during embryo fixation and capsule disappearance.. PLoS One 2014;9(12):e114414.
- Iqbal K, Chitwood JL, Meyers-Brown GA, Roser JF, Ross PJ. RNA-seq transcriptome profiling of equine inner cell mass and trophectoderm.. Biol Reprod 2014 Mar;90(3):61.
- Almiñana C, Heath PR, Wilkinson S, Sanchez-Osorio J, Cuello C, Parrilla I, Gil MA, Vazquez JL, Vazquez JM, Roca J, Martinez EA, Fazeli A. Early developing pig embryos mediate their own environment in the maternal tract.. PLoS One 2012;7(3):e33625.
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