Talk:Bovine Development
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Cite this page: Hill, M.A. (2024, April 18) Embryology Bovine Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Bovine_Development |
Bovine development original page
Animation http://www.ansi.okstate.edu/resource-room/reprod/all/animations/pregnancy_cow.htm
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Note - This sub-heading shows an automated computer PubMed search using the listed sub-heading term. References appear in this list based upon the date of the actual page viewing. Therefore the list of references do not reflect any editorial selection of material based on content or relevance. In comparison, references listed on the content page and discussion page (under the publication year sub-headings) do include editorial selection based upon relevance and availability. (More? Pubmed Most Recent)
Bovine Embryology
<pubmed limit=5>Bovine Embryology</pubmed>
Bovine Development
<pubmed limit=5>Bovine Development</pubmed>
2012
Expression of pluripotency master regulators during two key developmental transitions: EGA and early lineage specification in the bovine embryo
PLoS One. 2012;7(3):e34110. Epub 2012 Mar 29.
Khan DR, Dubé D, Gall L, Peynot N, Ruffini S, Laffont L, Le Bourhis D, Degrelle S, Jouneau A, Duranthon V. Source INRA UMR 1198 Biologie du Développement et de la Reproduction, Jouy en Josas, France.
Abstract
Pluripotency genes are implicated in mouse embryonic genome activation (EGA) and pluripotent lineage specification. Moreover, their expression levels have been correlated with embryonic term development. In bovine, however, little information is available about dynamics of pluripotency genes during these processes. In this study, we charted quantitative and/or qualitative spatio-temporal expression patterns of transcripts and proteins of pluripotency genes (OCT4, SOX2 and NANOG) and mRNA levels of some of their downstream targets in bovine oocytes and early embryos. Furthermore, to correlate expression patterns of these genes with term developmental potential, we used cloned embryos, having similar in vitro but different full term development rates. Our findings affirm: firstly, the core triad of pluripotency genes is probably not implicated in bovine EGA since their proteins were not detected during pre-EGA phase, despite the transcripts for OCT4 and SOX2 were present. Secondly, an earlier ICM specification of transcripts and proteins of SOX2 and NANOG makes them pertinent candidates of bovine pluripotent lineage specification than OCT4. Thirdly, embryos with low term development potential have higher transcription rates; nevertheless, precarious balance between pluripotency genes is maintained. This balance presages normal in vitro development but, probably higher transcription rate disturbs it at later stage that abrogates term development.
PMID 22479535
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3315523
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0034110
2010
A small set of extra-embryonic genes defines a new landmark for bovine embryo staging
Reproduction. 2010 Oct 6. [Epub ahead of print]
Degrelle SA, Le Cao KA, Heyman Y, Everts RE, Campion E, Richard C, Ducroix-Crepy C, Tian C, Lewin H, Renard JP, Robert-Granié C, Hue I.
S Degrelle, UMR Biologie du Developpement et Reproduction, INRA, JOUY EN JOSAS, 78350, France. Abstract Axis specification in the mouse is determined by a sequence of reciprocal interactions between embryonic and extra-embryonic tissues so that a few extra-embryonic genes appear as 'patterning' the embryo. Considering these interactions as essential but lacking in most mammals the genetically driven approaches used in the mouse and the corresponding patterning mutants, we examined whether a molecular signature originating from extra-embryonic tissues could relate to the developmental stage of the embryo proper and predict it. To this aim we profiled bovine extra-embryonic tissues at peri-implantation stages, when gastrulation and early neurulation occur, and analysed the subsequent expression profiles through the use of predictive methods as previously reported for tumour classification. A set of 6 genes (CALM1, CPA3, CITED1, DLD, HNRNPDL, TGFB3), half of which had not been previously associated to any extra-embryonic feature, appeared significantly discriminative and mainly dependent on embryonic tissues for its faithful expression. The predictive value of this set of genes for gastrulation and early neurulation stages, as assessed on naïve samples, was remarkably high (93%). In silico connected to the bovine orthologues of the mouse patterning genes, this gene set is proposed as new trait for embryo staging. As such, this will allow saving the bovine embryo proper for molecular or cellular studies. To us, it offers as well new perspectives for developmental phenotyping and modelling of embryonic/extra-embryonic co-differentiation.
PMID: 20926692
Modulation of the maternal immune system by the pre-implantation embryo
BMC Genomics. 2010 Aug 13;11:474.
Walker CG, Meier S, Littlejohn MD, Lehnert K, Roche JR, Mitchell MD.
DairyNZ Ltd,, Hamilton, New Zealand. Caroline.Walker@dairynz.co.nz Abstract BACKGROUND: A large proportion of pregnancy losses occur during the pre-implantation period, when the developing embryo is elongating rapidly and signalling its presence to the maternal system. The molecular mechanisms that prevent luteolysis and support embryo survival within the maternal environment are not well understood. To gain a more complete picture of these molecular events, genome-wide transcriptional profiles of reproductive day 17 endometrial tissue were determined in pregnant and cyclic Holstein-Friesian dairy cattle.
RESULTS: Microarray analyses revealed 1,839 and 1,189 differentially expressed transcripts between pregnant and cyclic animals (with > or = 1.5 fold change in expression; P-value < 0.05, MTC Benjamini-Hochberg) in caruncular and intercaruncular endometrium respectively. Gene ontology and biological pathway analysis of differentially expressed genes revealed enrichment for genes involved in interferon signalling and modulation of the immune response in pregnant animals.
CONCLUSION: The maternal immune system actively surveys the uterine environment during early pregnancy. The embryo modulates this response inducing the expression of endometrial molecules that suppress the immune response and promote maternal tolerance to the embryo. During this period of local immune suppression, genes of the innate immune response (in particular, antimicrobial genes) may function to protect the uterus against infection.
PMID: 20707927
http://www.biolreprod.org/content/79/6/1219.full
"The number of morphologically healthy oocytes in the ovaries of mammals is remarkably variable at birth, ranging, for example, from 350 000 to 1 100 000 in humans [1–3] and approximately 14 000 to 250 000 in cattle [4, 5]"
2006
Dynamics of global transcriptome in bovine matured oocytes and preimplantation embryos
Proc Natl Acad Sci U S A. 2006 Dec 12;103(50):18905-10. Epub 2006 Dec 1.
Misirlioglu M, Page GP, Sagirkaya H, Kaya A, Parrish JJ, First NL, Memili E.
Department of Animal and Dairy Sciences, Mississippi State University, Mississippi State, MS 39762, USA.
Abstract Global activation of the embryonic genome is the most critical event in early mammalian development. After fertilization, a rich supply of maternal proteins and RNAs support development whereas a number of zygotic and embryonic genes are expressed in a stage-specific manner leading to embryonic genome activation (EGA). However, the identities of embryonic genes expressed and the mechanism(s) of EGA are poorly defined in the bovine. Using the Affymetrix bovine-specific DNA microarray as the biggest available array at present, we analyzed gene expression at two key stages of bovine development, matured oocytes (MII) and 8-cell-stage embryos, constituting the ultimate reservoir for life and a stage during which EGA takes place, respectively. Key genes in regulation of transcription, chromatin-structure cell adhesion, and signal transduction were up-regulated at the 8-cell stage as compared with 8-cell embryos treated with alpha-amanitin and MII. Genes controlling DNA methylation and metabolism were up-regulated in MII. These changes in gene expression, related to transcriptional machinery, chromatin structure, and the other cellular functions occurring during several cleavage stages, are expected to result in a unique chromatin structure capable of maintaining totipotency during embryogenesis and leading to differentiation during postimplantation development. Dramatic reprogramming of gene expression at the onset of development also has implications for cell plasticity in somatic cell nuclear transfer, genomic imprinting, and cancer.
PMID: 17142320
