Publications by authors named "Bert DE Groef"

The pleomorphic adenoma gene 1 (Plag1) is a transcription factor involved in the regulation of growth and cellular proliferation. Here, we report the spatial distribution and functional implications of PLAG1 expression in the adult mouse brain. We identified Plag1 promoter-dependent β-galactosidase expression in various brain structures, including the hippocampus, cortex, choroid plexus, subcommisural organ, ependymal cells lining the third ventricle, medial and lateral habenulae and amygdala.

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As embryonic development proceeds, numerous organs need to coil, bend or fold in order to establish their final shape. Generally, this occurs so as to maximise the surface area for absorption or secretory functions (e.g.

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The proto-oncogene pleomorphic adenoma gene 1 (Plag1) encodes a zinc finger transcription factor. PLAG1 is part of the high motility group AT hook-2 (HGMA2)-PLAG1-insulin-like growth factor 2 (IGF2) pathway that, when disrupted, leads to Silver-Russell syndrome, a severe form of intrauterine growth restriction. With little known about PLAG1's role in normal physiology, this study is the first to characterise the behavioural phenotype of PLAG1-deficient mice.

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Foetus sterility until parturition is under debate due to reports of microorganisms in the foetal environment and meconium. Sufficient controls to overcome sample contamination and provide direct evidence of microorganism viability in the pre-rectal gastrointestinal tract (GIT) have been lacking. We conducted molecular and culture-based analyses to investigate the presence of a microbiome in the foetal GIT of calves at 5, 6 and 7 months gestation, while controlling for contamination.

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Background: The transcription factor pleomorphic adenoma gene 1 (PLAG1) is required for male fertility. Mice deficient in PLAG1 exhibit decreased sperm motility and abnormal epididymal tubule elongation and coiling, indicating impaired sperm maturation during epididymal transit. However, the downstream transcriptomic profile of the Plag1 knockout (KO; Plag1 ) murine epididymis is currently unknown.

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The highly-conserved Grainyhead-like (Grhl) transcription factors are critical regulators of embryogenesis that regulate cellular survival, proliferation, migration and epithelial integrity, especially during the formation of the craniofacial skeleton. Family member Grhl2 is expressed throughout epithelial tissues during development, and loss of Grhl2 function leads to significant defects in neurulation, abdominal wall closure, formation of the face and fusion of the maxilla/palate. Whereas numerous downstream target genes of Grhl2 have been identified, very little is known about how this crucial developmental transcription factor itself is regulated.

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The laboratory exercise described here aims to provide a relevant context for learning basic DNA techniques in an introductory animal science course at tertiary level. In two 4-hr laboratory sessions, students assess the suitability of bulls for inclusion in a gene-assisted selection program for A2 β-casein by genotyping commercial bull sperm. Sperm cells are lysed to extract the genomic DNA, and PCR with primers for the β-casein gene is performed.

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Mice deficient in the transcription factor pleomorphic adenoma gene 1 (PLAG1) exhibit reproductive issues that are characterized, in part, by decreased progressive sperm motility in the male. However, the underlying cause of this impairment is unknown. As epididymal transit is critical for sperm maturation and motility, the morphology of the epididymis of Plag1-deficient mice was investigated and the spatial expression patterns of PLAG1 protein and mRNA were identified.

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Corticotropin-releasing hormone (CRH) is known to act as a potent thyrotropin-releasing factor in non-mammalian species such as chicken and bullfrog. This interaction is mediated by type 2 CRH receptors (CRHR2) expressed by the thyrotropes in the pituitary gland. However, the response elements (REs) and their corresponding transcription factors (TFs) that control CRHR2 expression in thyrotropes are not known.

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Pleomorphic adenoma gene 1 (PLAG1) is a transcription factor involved in cancer and growth. We discovered a de novo DNA motif containing a PLAG1 binding site in the promoters of genes activated during zygotic genome activation (ZGA) in human embryos. This motif was located within an Alu element in a region that was conserved in the murine B1 element.

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Many G protein-coupled receptors have splice variants, with potentially different pharmaceutical properties, expression patterns and roles. The human brain expresses three functional splice variants of the type 2 corticotropin-releasing hormone: CRHR2α, -β and -γ. CRHR2γ has only been reported in humans, but its phylogenetic distribution, and how and when during mammalian evolution it arose, is unknown.

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Veterinary diagnostic clinicians are increasingly presented with emaciated animals involved in suspected neglect cases. A rise in public awareness and media attention towards animal welfare, combined with changes in legislation and a demand for a higher standard of evidence be presented in animal neglect cases submitted for prosecutions, have created a need for an objective measurement of starvation, particularly given the lack of quantitative assessments at post-mortem examinations. Bone marrow fat (BMF) is the final fat reserve to be mobilised for energy by a calorie-deprived animal during a state of emaciation.

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Knockout of pleomorphic adenoma gene 1 (PLAG1) in mice results in reduced fertility. To investigate whether PLAG1 is involved in reproductive control by the hypothalamo-pituitary system in males, we determined PLAG1 expression sites and compared gene expression between hypothalami and pituitary glands from Plag1 knockout and wildtype animals. Abundant expression of PLAG1 was detected throughout the pituitary gland, including gonadotropes and somatotropes.

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The Mexican axolotl (Ambystoma mexicanum) is a salamander species that does not undergo metamorphosis, resulting in the retention of juvenile characteristics in the mature breeding stage (paedomorphosis). Here we review the endocrinological studies investigating the proximate cause of axolotl paedomorphosis with a focus on the hypothalamo-pituitary-thyroid (HPT) axis. It is well established that axolotl paedomorphosis is a consequence of low activity of the HPT axis.

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In chicken, corticotropin-releasing hormone (CRH) acts as a thyrotropin (TSH)-releasing factor, mediated by the type 2 CRH receptor (CRHR2) on the thyrotropes of the pituitary gland. It is not known whether CRH also controls TSH release in non-precocial avian species that have a different pattern of thyroidal activity during their life cycle. Therefore, we investigated the TSH-releasing capacity of CRH in an altricial species, the zebra finch (Taeniopygia guttata).

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Background: Canids are definitive hosts of the apicomplexan parasite Neospora caninum, the leading cause of abortion in cattle worldwide. For horizontal transmission from canids to occur, oocysts of N. caninum must be shed by the definitive host into the environment of susceptible intermediate hosts such as cattle.

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Deficiency in pleomorphic adenoma gene 1 (PLAG1) leads to reduced fertility in male mice, but the mechanism by which PLAG1 contributes to reproduction is unknown. To investigate the involvement of PLAG1 in testicular function, we determined (i) the spatial distribution of PLAG1 in the testis using X-gal staining; (ii) transcriptomic consequences of PLAG1 deficiency in knock-out and heterozygous mice compared to wild-type mice using RNA-seq; and (iii) morphological and functional consequences of PLAG1 deficiency by determining testicular histology, daily sperm production and sperm motility in knock-out and wild-type mice. PLAG1 was sparsely expressed in germ cells and in Sertoli cells.

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In chicken embryos, intravenous injection of corticotropin-releasing hormone (CRH) causes the release of both corticosteroids and thyroid hormones. These hormones initiate and enhance the hatching process, raising the possibility that CRH treatment of the late chicken embryo could accelerate hatching and/or decrease the spread of hatching. We performed a series of exploratory tests to investigate whether in ovo delivery methods of CRH other than intravenous injection that are more practical in a commercial setting, affect hatching time in broilers.

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Several short-term whole-organism bioassays based on transgenic aquatic models are now under validation by the OECD (Organization for Economic Co-operation and Development) to become standardized test guidelines for the evaluation of the endocrine activity of substances. Evaluation of the endocrine disrupting capacity of pesticides will be a domain of applicability of these future reference tests. The herbicide linuron and the insecticide fenoxycarb are two chemicals commonly used in agricultural practices.

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Like all vertebrates, marsupials respond to stressors with the activation of the hypothalamo-pituitary-adrenal axis. However, peptides operating at the higher regulatory levels of this hormonal system, i.e.

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Urocortin 3 (UCN3) is a neuropeptide believed to regulate stress-coping responses by binding to type 2 corticotropin-releasing hormone receptors. Here, we report the cloning and brain distribution of UCN3 mRNA in a sauropsid-the chicken, Gallus gallus. Mature chicken UCN3 is predicted to be a 40-amino acid peptide showing high sequence similarity to human (93%), mouse (93%), and Xenopus (88%) UCN3.

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The use of bone marrow fat percentage has been recommended in assessing body condition at the time of death in wild and domestic ruminants, but few studies have looked at the effects of time and exposure on animal bone marrow. We investigated the utility of bone marrow fat extraction as a tool for establishing antemortem body condition in postmortem specimens from sheep and cattle, particularly after exposure to high heat, and compared different techniques of fat extraction for this purpose. Femora were collected from healthy and "skinny" sheep and cattle.

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Hormones, particularly thyroid hormones and corticosteroids, play critical roles in vertebrate life stage transitions such as amphibian metamorphosis, hatching in precocial birds, and smoltification in salmonids. Since they synergistically regulate several metabolic and developmental processes that accompany vertebrate life stage transitions, the existence of extensive cross-communication between the adrenal/interrenal and thyroidal axes is not surprising. Synergies of corticosteroids and thyroid hormones are based on effects at the level of tissue hormone sensitivity and gene regulation.

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Pleomorphic adenoma gene 1 (PLAG1) belongs to the PLAG family of zinc finger transcription factors along with PLAG-like 1 and PLAG-like 2. The PLAG1 gene is best known as an oncogene associated with certain types of cancer, most notably pleomorphic adenomas of the salivary gland. While the mechanisms of PLAG1-induced tumorigenesis are reasonably well understood, the role of PLAG1 in normal physiology is less clear.

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Microbial communities are affected by diet and play a role in the successful transition from milk to a solid diet. The response of microorganisms in the gastrointestinal tract of Holstein bull calves to the uptake of milk with solid feed (control treatment; CT), or milk without solid feed (milk-only treatment; MT) during the first 3 weeks of life was investigated. Samples were collected from the rumen (fluid and tissue), abomasum (fluid), cecum (fluid and tissue) and feces at 7, 14 and 20 days of age.

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