OCT4/POU5F1 is indispensable for the lineage differentiation of the inner cell mass in bovine embryos.

The mammalian blastocyst undergoes two lineage segregations, that is, formation of the trophectoderm and subsequently differentiation of the hypoblast (HB) from the inner cell mass, leaving the epiblast (EPI) as the remaining pluripotent lineage. To clarify the expression patterns of markers specific for these lineages in bovine embryos, we analyzed day 7, 9, and 12 blastocysts completely produced in vivo by staining for OCT4, NANOG, SOX2 (EPI), and GATA6, SOX17 (HB) and identified genes specific for these developmental stages in a global transcriptomics approach. To study the role of OCT4, we generated OCT4-deficient (OCT4 KO) embryos via somatic cell nuclear transfer or in vitro fertilization.

Mitochondrial DNA Depletion in Granulosa Cell Derived Nuclear Transfer Tissues.

Somatic cell nuclear transfer (SCNT) is a key technology with broad applications that range from production of cloned farm animals to derivation of patient-matched stem cells or production of humanized animal organs for xenotransplantation. However, effects of aberrant epigenetic reprogramming on gene expression compromise cell and organ phenotype, resulting in low success rate of SCNT. Standard SCNT procedures include enucleation of recipient oocytes before the nuclear donor cell is introduced.

Initiation of Conceptus Elongation Coincides with an Endometrium Basic Fibroblast Growth Factor (FGF2) Protein Increase in Heifers.

Fibroblast growth factors (FGF) play an important role during embryo development. To date, the role of FGF and the respective receptors (FGFR) during the preimplantation phase in cattle are not fully characterized. We examined FGF1, FGF2, FGFR1, FGFR2, and FGFR3 in cyclic and early pregnant heifers at Days 12, 15, and 18 after insemination (Day 0).

Vascular Endothelial Growth Factor A and VEGFR-1 Change during Preimplantation in Heifers.

Vascular endothelial growth factor A (VEGFA) plays a critical angiogenic role in the endometrium of placentalia during preimplantation. The role of VEGFA and its receptors is not fully characterised in bovine reproduction. We analysed the mRNA expression of VEGFA isoforms 121, 165 and 189, and VEGF receptors 1 and 2 in three experimental settings (A, B and C).

Novel sampling procedure to characterize bovine subclinical endometritis by uterine secretions and tissue.

Subclinical endometritis (SE) in cattle is defined as clinically unapparent inflammation of the endometrium. It is reported to impair fertility in affected cows and causes economic loss within the dairy industry. A gold standard for diagnosis of SE has not been set.

The Munich MIDY Pig Biobank - A unique resource for studying organ crosstalk in diabetes.

Objective: The prevalence of diabetes mellitus and associated complications is steadily increasing. As a resource for studying systemic consequences of chronic insulin insufficiency and hyperglycemia, we established a comprehensive biobank of long-term diabetic transgenic pigs, a model of mutant gene-induced diabetes of youth (MIDY), and of wild-type (WT) littermates.

Methods: Female MIDY pigs (n = 4) were maintained with suboptimal insulin treatment for 2 years, together with female WT littermates (n = 5).

Isolation, Structure Elucidation, and (Bio)Synthesis of Haprolid, a Cell-Type-Specific Myxobacterial Cytotoxin.

Myxobacteria are well-established sources for novel natural products exhibiting intriguing bioactivities. We here report on haprolid (1) isolated from Byssovorax cruenta Har1. The compound exhibits an unprecedented macrolactone comprising four modified amino acids and a polyketide fragment.

Isolation, Structure Elucidation, Biosynthesis, and Synthesis of Antalid, a Secondary Metabolite from Polyangium species.

The isolation, structure elucidation, and synthesis of antalid (1), a novel secondary metabolite from Polyangium sp., is described herein. The structure elucidation of 1 was performed with the aid of mass spectrometry, high field NMR experiments, and crystal structure analysis.

Phytohemagglutinin facilitates the aggregation of blastomere pairs from Day 5 donor embryos with Day 4 host embryos for chimeric bovine embryo multiplication.

Multiplication of bovine embryos by the production of aggregation chimeras is based on the concept that few blastomeres of a donor embryo form the inner cell mass (ICM) and thus the embryo proper, whereas cells of a host embryo preferentially contribute to the trophectoderm (TE), the progenitor cells of the embryonic part of the placenta. We aggregated two fluorescent blastomeres from enhanced green fluorescent protein (eGFP) transgenic Day 5 morulae with two Day 4 embryos that did not complete their first cleavage until 27 hours after IVF and tested the effect of phytohemagglutinin-L (PHA) on chimeric embryo formation. The resulting blastocysts were characterized by differential staining of cell lineages using the TE-specific factor CDX2 and confocal laser scanning microscopy to facilitate the precise localization of eGFP-positive cells.

Designation of type strains for seven species of the order Myxococcales and proposal for neotype strains of Cystobacter ferrugineus, Cystobacter minus and Polyangium fumosum.

Ten species of the order Myxococcales with validly published names are devoid of living type strains. Four species of the genus Chondromyces are represented by dead herbarium samples as the type material. For a species of the genus Melittangium and two species of the genus Polyangium, no physical type material was assigned at the time of validation of the names or later on.

Transcriptome changes in the porcine endometrium during the preattachment phase.

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.

Tissue-specific and minor inter-individual variation in imprinting of IGF2R is a common feature of Bos taurus Concepti and not correlated with fetal weight.

The insulin-like growth factor 2 receptor (IGF2R) is essential for prenatal growth regulation and shows gene dosage effects on fetal weight that can be affected by in-vitro embryo culture. Imprinted maternal expression of murine Igf2r is well documented for all fetal tissues excluding brain, but polymorphic imprinting and biallelic expression were reported for IGF2R in human. These differences have been attributed to evolutionary changes correlated with specific reproductive strategies.

Isolation, biological activity evaluation, structure elucidation, and total synthesis of eliamid: a novel complex I inhibitor.

Eliamid is a secondary metabolite isolated from two bacterial strains. This molecule features a linear polyketide backbone terminated by a tetramic acid amide moiety. Among other biological activities, eliamid shows a high and specific cytostatic action on human lymphoma and cervix carcinoma cell lines.

Comparison of the effects of early pregnancy with human interferon, alpha 2 (IFNA2), on gene expression in bovine endometrium.

Interferon tau (IFNT), a type I IFN similar to alpha IFNs (IFNA), is the pregnancy recognition signal produced by the ruminant conceptus. To elucidate specific effects of bovine IFNT and of other conceptus-derived factors, endometrial gene expression changes during early pregnancy were compared to gene expression changes after intrauterine application of human IFNA2. In experiment 1, endometrial tissue samples were obtained on Day (D) 12, D15, and D18 postmating from nonpregnant or pregnant heifers.

Cell arrest and cell death in mammalian preimplantation development: lessons from the bovine model.

Background: The causes, modes, biological role and prospective significance of cell death in preimplantation development in humans and other mammals are still poorly understood. Early bovine embryos represent a very attractive experimental model for the investigation of this fundamental and important issue.

Methods And Findings: To obtain reference data on the temporal and spatial occurrence of cell death in early bovine embryogenesis, three-dimensionally preserved embryos of different ages and stages of development up to hatched blastocysts were examined in toto by confocal laser scanning microscopy.

Reduced amino acids in the bovine uterine lumen of cloned versus in vitro fertilized pregnancies prior to implantation.

Fetal overgrowth and placental abnormalities frequently occur in pregnancies following somatic cell nuclear transfer (SCNT). An optimal intrauterine supply of amino acids (AA) is of specific importance for the development of the bovine preimplantation embryo, and a defective regulation of AA supply might contribute to pregnancy failures. Thus, we analyzed 41 AA and derivatives by liquid chromatography-tandem mass spectrometry in uterine flushings of day 18 pregnant heifers carrying in vitro fertilized (IVF) or SCNT embryos, which were cultured under identical conditions until transfer to recipients.

Immunological mechanisms to establish embryo tolerance in early bovine pregnancy.

A well-balanced immunological interaction between mother and the semi-allogenic embryo is of particular importance. The objective of the present study was to analyse mechanisms of immune tolerance in bovine pregnancy during peri-implantation. Simmental heifers inseminated with either cryopreserved spermatozoa or seminal plasma were killed 12, 15 or 18 days after oestrus.

Increase of essential amino acids in the bovine uterine lumen during preimplantation development.

Amino acids (AAs) are crucial for the developing conceptus prior to implantation. To provide insights into the requirements of the bovine embryo, we determined the AA composition of the uterine fluid. At days 12, 15, and 18 post-estrus, the uteri of synchronized pregnant and non-pregnant Simmental heifers were flushed for the analysis of 41 AAs and their derivatives by liquid chromatography-tandem mass spectrometry.

New cytogenetically visible copy number variant in region 8q21.2.

Background: Cytogenetically visible unbalanced chromosomal abnormalities (UBCA), reported for >50 euchromatic regions of almost all human autosomes, are comprised of a few megabases of DNA, and carriers are in many cases clinically healthy. It may be speculated, that some of the UBCA may be similar or identical to copy number variants (CNV) of the human genome.

Results: Here we report on a yet unreported cytogenetically visible copy number variant (CNV) in the long arm of chromosome 8, region 8q21.

Bovine endometrial metallopeptidases MMP14 and MMP2 and the metallopeptidase inhibitor TIMP2 participate in maternal preparation of pregnancy.

Early embryonic development is critically dependent on both maternal preparation and embryonic signalling of pregnancy. Matrix metallopeptidases (MMP) contribute to spatial and temporal matrix remodeling in the bovine endometrium. In this study we observed distinct changes in expression of MMP2, MMP14, and the metallopeptidase inhibitor TIMP2 between different phases of the estrous cycle indicating an endocrine regulation.

Quantification of leukocyte genomic 5-methylcytosine levels reveals epigenetic plasticity in healthy adult cloned cattle.

Successful somatic cell nuclear transfer (SCNT) requires epigenetic reprogramming of a differentiated donor cell nucleus. Incorrect reprogramming of epigenetic markings such as DNA methylation is associated with compromised prenatal development and postnatal abnormalities. Clones that survive into adulthood, in contrast, are assumed to possess a normalized epigenome corresponding to their normal phenotype.

Foetal stress responses to euthanasia of pregnant sheep.

The study was designed to evaluate foetal stress responses in midgestational (G1) and near-term (G2) pregnant ewes euthanized either by intravenous administration of pentobarbital (group P) or electrical current (group E). After the ewe's death foetal lambs were delivered by caesarean section and remained attached to the ewe by the umbilical cord. Foetal vitality, reflexes, heart rate, blood pressure, rectal body temperature, venous pCO2, pH and lactic acid were monitored.