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B Brenig

Publications and source records attributed to B Brenig.

At least 127 records · Page 7Linked to original sources
PubMed1996

[The role of proteolipid proteins in the development of congenital tremors type AIII: a review].

During the sixties a sex-specific, hereditary form of congenital tremor type A (CT A) appeared which was classified as CT AIII. The symptoms were the same as in other subtypes and only autopsy and differential diagnosis showed the distinctive signs of this disease. Pigs suffering from CT AIII fail to develop a tight myelin sheath and contain a reduced number of oligodendrocytes in their CNS whereas no pathological changes can be detected in the PNS. The same symptoms as with CT AIII appear in various disorders in animals and humans. The cause for jimpy in mice was traced back to a mutation in the PLP gene. In the course of these findings different mutations in the human PLP gene were identified and shown to be the reason for the rare Pelizaeus-Merzbacher-Disease and the spastic paraplegia type 2. If one considers the clinical and histological similarities between PLP mutants and CT AIII in pigs it is reasonable to assume that this X-linked gene plays a major role in the development of CT AIII. In the following we describe the isolation and characterization of the porcine PLP gene and its possible involvement in congenital tremor type AIII.

Animals↗
PubMed1996

[Muscle specific gene expression during embryonal development].

The myogenic bHLH-proteins play a crucial role in the determination and tissue specific gene expression in skeletal muscle. Being able to regulate themselves and the other members of their family they establish the myogenic lineage in the precursor cells of the skeletal muscle. The precise mechanisms that lead to the manifestation of myogenic cells in vivo are still unknown, but much has been learned from the behaviour of established cell lines and targeted mutations in the myogenic regulatory factors (MRFs). This review will focus on the results of these experiments and outline the major regulatory pathways which lead to the formation of skeletal muscle cells.

Animals↗
PubMed1996

[The problem of breeding for fertility].

The reproductive success in domestic animals is an important factor towards the economical production of livestock. Thus, a lot of energy has been spent on the amelioration of the reproduction by means of genetics but no considerable success was achieved since the additive genetic variance is low. This communication is supposed to elucidate its molecular biological basis in reproduction and furthermore, the article should point out the way in research how to improve reproductive parameters. We propose to characterize all sorts of genes and their gene products that are involved in reproduction. This is to realize a full understanding of the sperm egg interaction and to derive benefit from effects like heterosis.

Animals↗
PubMed1995

Construction of a porcine YAC library and mapping of the cardiac muscle ryanodine receptor gene to chromosome 14q22-q23.

Large-scale physical mapping of the porcine genome has been limited because up to now no suitable genomic libraries for this purpose have been available. Therefore, we have constructed a yeast artificial chromosome (YAC) library from porcine lymphocytes. The library was cloned in the amplifiable vector pCGS966. A total of 10080 YAC clones was obtained and has been ordered into 105 96-well microtiter plates. An average insert size of 300 kb was calculated from the analysis of 78 randomly selected clones, giving a one-fold coverage of the porcine genome. To analyze the complexity, we have screened the library for five different genes and isolated four different clones containing parts of three of these genes. One YAC clone harboring parts of the porcine cardiac muscle ryanodine receptor (RYR2) gene allowed us to assign this locus to Chromosome (Chr) 14q22-q23. The data were confirmed by PCR analysis of a rodent-porcine hybrid cell panel.

Animals↗
PubMed1994

[Biotechnology in veterinary medicine and animal production].

The rapid development of modern biotechnology has introduced a new dimension to veterinary medicine and animal breeding. Genome analysis of important breeding species will ultimately allow to detect and consequently to eliminate any possible genetic disorder. Moreover, infectious diseases may also be detected easier and more reliable. The production of transgenic livestock opens the possibility to generate animals with improved health and productivity without time consuming breeding programmes. In the following review I will focus on the description of recent developments in the application of molecular biological techniques in veterinary medicine and animal production. Special emphasis will be given to the physiological consequences of transgene expression rather than the techniques for the production of transgenic animals.

Animal Husbandry↗
PubMed1993

Genomic organization of the porcine skeletal muscle ryanodine receptor (RYR1) gene coding region 4624 to 7929.

Excitation-contraction coupling in skeletal muscle is mediated by two calcium channels located in the membranes of the transverse tubule and the sarcoplasmic reticulum. Calcium is released from the terminal cisternae of the sarcoplasmic reticulum via the ryanodine receptor. Abnormal increases in myoplasmic free calcium caused by a defect in the ryanodine receptor have been reported in malignant hyperthermia. Malignant hyperthermia is a life-threatening pharmacogenetic disorder in a variety of species and is triggered by volatile anesthetics and depolarizing muscle relaxants. To study the genomic organization of the porcine skeletal muscle ryanodine receptor gene, we have isolated six genomic fragments spanning approximately 80 kb of chromosomal DNA. In this report, we describe the genomic organization of a 15.5-kb genomic fragment comprising 18 exons coding for region 4624 to 7929 of the porcine skeletal muscle ryanodine receptor gene.

Animals↗
PubMed1992

Transgenic pigs carrying cDNA copies encoding the murine Mx1 protein which confers resistance to influenza virus infection.

An important aspect of gene transfer into farm animals is the improvement of disease resistance. The mouse Mx1 protein is known to be sufficient to confer resistance to influenza viruses. Gene constructs containing the mouse Mx1 cDNA controlled by the human metallothionein IIA promoter (hMTIIA::Mx), the SV40 early enhancer/promoter region (SV40::Mx) and the mouse Mx1 promoter (mMx::Mx) were transferred into pigs. The results of the gene transfer experiments with the hMTIIA::Mx and the SV40::Mx constructs indicate that the permanent high-level synthesis of Mx1 might be deleterious to the organism: the gene transfer efficiency was surprisingly low, and all transgenic piglets born had rearrangements in their transgene copies that abolished protein synthesis. The use of the interferon (IFN)- and virus-inducible mMx::Mx construct resulted in normal gene transfer efficiency. Two transgenic pig lines could be established which expressed IFN-inducible mouse Mx1 mRNA. Extensive protein analysis did not detect mouse Mx1 in IFN-treated transgenic animals.

Animals↗
PubMed1992

Genomic organization and analysis of the 5' end of the porcine ryanodine receptor gene (ryr1).

In this study we describe the isolation of genomic clones of the 5' region of the porcine ryanodine receptor gene, a candidate for malignant hyperthermia in pigs and humans. The recombinants were isolated from a porcine liver, genomic DNA library in phage EMBL3A after screening with PCR amplified DNA fragments. The exon/intron structure of the ryanodine receptor gene was determined by DNA sequencing. Based on the sequence data it was possible to develop a simple test for the detection of malignant hyperthermia susceptible and normal pigs.

Animals↗
PubMed1991

Human VNTR sequences in porcine HTF-islands.

Mapping of complex genomes has been influenced substantially by the isolation of locus-specific, but repetitive DNA elements known as VNTRs. Since a high GC-content is characteristic of most of these elements one might expect them to be clustered at least partially in CpG-islands. To address this question we have constructed a porcine liver DNA NotI-linkage library in pUC18 using isolated HTF-islands. HpaII tiny fragments ranging from less than 100 bp to 1 kb in length were randomly selected and analysed by sequencing. As expected from the source of DNA the clones were rich in CpG-, C- and G-content. Several clones exhibiting a repetitive (GGC)n-motif and sequences originally present in human VNTR-markers were shown to detect DNA fingerprints in different species (Homo sapiens, Sus scrofa domestica, Gallus domesticus, Glycine max, Saccharomyces cerevisiae). A subset of clones was used for hybridization experiments with porcine DNA and were shown to detect single-copy linkage fragments.

Animals↗
PubMed1991

[Unexpected transgene expression of a mammary-specific growth hormone gene construct in Bergmann glial cells of the mouse].

Pronuclear microinjection was used to produce transgenic mice harboring gene constructs, in which 110 base pairs (WAP1) or 2.4 kilobases (WAP2) of the 5' flanking sequences of the whey acidic protein (WAP) gene were fused to human growth hormone (hGH)-coding sequences. Female WAP-hGH transgenic mice expressed the transgenes in the mammary gland, the expression of the WAP2-hGH transgene mirroring that of the endogenous WAP gene. When other organs were examined, high level expression of hGH was observed in the brains of WAP2-hGH transgenic mice. Using in situ hybridization and immunohistochemistry, hGH expression from the transgene was seen to occur specifically in Bergmann glia cells. While normally neither WAP nor hGH is expressed in this type of cell, it appears that a combination of the regulatory region of the WAP gene and the hGH structural gene results in a novel tissue specificity in Bergmann glia cells.

Animals↗
PubMed1989

Multiple consequences of human growth hormone expression in transgenic mice.

Transgenic mice harbouring growth hormone gene constructs have been produced by DNA microinjection into pronuclei of fertilized oocytes. We examined transgenic mice carrying a mouse metallothionein I-human growth hormone (mMT I-hGH) fusion gene. Here, we present our results concerning gene integration, gene expression, and phenotypical, clinical and pathomorphological alterations found in mice expressing the hGH transgene. Body and organ growth was significantly increased in transgenic mice, whereas fertility was found to be reduced. The life-span was markedly shortened indicating detrimental side-effects of the high levels of circulating hGH. Lesions of kidneys, liver and heart were the predominant pathological findings. Our own results are compared with those obtained by other authors who have investigated mice carrying rat, bovine or ovine growth hormone fusion genes. GH-transgenic mice may serve as a model system to investigate ectopic expression of hormone genes thus circumventing endogenous feedback control mechanisms in complex hormonal cascades.

Animals↗
PubMed1989

[The structure of eukaryotic genes].

The structure of eukaryotic transcription units and already known DNA elements which influence gene expression and eukaryotic gene regulation are described. In recent years molecular genetics approaches have been used to identify and characterize the molecular anatomy of protein-coding eukaryotic genes. Within these genes there are modular sequences, consisting of arrays of short, highly conserved recognition elements that are essential for the initiation of transcription, translation, and tissue-specificity of gene expression. The skillful combination of promoters, enhancers and other regulatory sequences allows the expression of every gene in every organ or tissue of a transgenic animal.

Animals↗
PubMedDate not supplied

Mapping of QTL for Body Conformation and Behavior in Cattle.

Genome scans for quantitative trait loci (QTL) in farm animals have concentrated on primary production and health traits, and information on QTL for other important traits is rare. We performed a whole genome scan in a granddaughter design to detect QTL affecting body conformation and behavior in dairy cattle. The analysis included 16 paternal half-sib families of the Holstein breed with 872 sons and 264 genetic markers. The markers were distributed across all 29 autosomes and the pseudoautosomal region of the sex chromosomes with average intervals of 13.9 cM and covering an estimated 3155.5 cM. All families were analyzed jointly for 22 traits using multimarker regression and significance thresholds determined empirically by permutation. QTL that exceeded the experiment-wise significance threshold (5% level) were detected on chromosome 6 for foot angle, teat placement, and udder depth, and on chromosome 29 for temperament. QTL approaching experiment-wise significance (10% level) were located on chromosome 6 for general quality of feet and legs and general quality of udder, on chromosome 13 for teat length, on chromosome 23 for general quality of feet and legs, and on chromosome 29 for milking speed. An additional 51 QTL significant at the 5% chromosome-wise level were distributed over 21 chromosomes. This study provides the first evidence for QTL involved in behavior of dairy cattle and identifies QTL for udder conformation on chromosome 6 that could form the basis of recently reported QTL for clinical mastitis.

Animals↗