Genetische Diagnostik der amyotrophen Lateralsklerose

Amyotrophic lateral sclerosis (ALS) is a rapidly progressing disease, which is accompanied by degeneration of both the upper (cortical) and the lower (spinal and bulbar) motoneurons. Clinically it is primarily characterized by a continuously and systematically spreading of muscular paresis and atrophy. The discovery of many novel ALS genes advanced the genetics of ALS rapidly within the past few years. Beyond the well-established superoxide dismutase 1 (SOD1) gene, chromosome 9 open reading frame 72 (C9ORF72), which turned out to be the most frequent ALS gene in Caucasians, TAR DNA binding protein (TARDBP) and fused in sarcoma (FUS) were recently added to the list of ALS genes. In addition, several rare ALS genes have been identified, which are mostly of cell biological and functional interest. The rapidly growing number of known ALS genes as well as the broadened phenotypic variability has increased the complexity of genetic diagnosis and counseling of ALS patients.     

On the toxicokinetics and the metabolism of deoxynivalenol (don) in the pig

Eleven castrated male pigs weighing 88.1?±?3.9?kg on average were adapted to a diet containing DON (4.2?mg DON/kg) over a period of 7 days. Feed was given restrictively with 1.1?kg per meal (two meals per day). On the day of measurement, all pigs were slaughtered at different time intervals following the morning meal containing DON (1, 2, 3, 4, 5, 6, 8, 15, 18 and 24?h after feeding), with the exception of one pig which was slaughtered unfed. DON and de-epoxy-DON were analysed in serum and digesta from consecutive segments of the digestive tract (stomach, small intestine divided into three parts of a similar length, caecum, colon, rectum). DON was rapidly and nearly completely absorbed while passing through the stomach and the proximal small intestine. Maximum serum concentration appeared 4.1?h after the DON-containing meal and half of the systemically absorbed DON was eliminated after 5.8?h. De-epoxy-DON appeared in increasing proportions from the distal small intestine and reached approximately 80% of the sum of DON plus de-epoxy-DON in faeces collected from the rectum. It was concluded that de-epoxydation of DON, which primarily occurs in the hindgut, probably does not contribute much to a detoxification in the pig.     

Plant-derived pharmaceuticals for the developing world

Plant-produced vaccines and therapeutic agents offer enormous potential for providing relief to developing countries by reducing the incidence of infant mortality caused by infectious diseases. Vaccines derived from plants have been demonstrated to effectively elicit an immune response. Biopharmaceuticals produced in plants are inexpensive to produce, require fewer expensive purification steps, and can be stored at ambient temperatures for prolonged periods of time. As a result, plant-produced biopharmaceuticals have the potential to be more accessible to the rural poor. This review describes current progress with respect to plant-produced biopharmaceuticals, with a particular emphasis on those that target developing countries. Specific emphasis is given to recent research on the production of plant-produced vaccines toward human immunodeficiency virus, malaria, tuberculosis, hepatitis B virus, Ebola virus, human papillomavirus, rabies virus and common diarrheal diseases. Production platforms used to express vaccines in plants, including nuclear and chloroplast transformation, and the use of viral expression vectors, are described in this review. The review concludes by outlining the next steps for plant-produced vaccines to achieve their goal of providing safe, efficacious and inexpensive vaccines to the developing world.     

Crystal structure of the p38 alpha-MAPKAP kinase 2 heterodimer

The p38 signaling pathway is activated in response to cell stress and induces production of proinflammatory cytokines. P38alpha is phosphorylated and activated in response to cell stress by MKK3 and MKK6 and in turn phosphorylates a number of substrates, including MAPKAP kinase 2 (MK2). We have determined the crystal structure of the unphosphorylated p38alpha-MK2 heterodimer. The C-terminal regulatory domain of MK2 binds in the docking groove of p38alpha, and the ATP-binding sites of both kinases are at the heterodimer interface. The conformation suggests an extra mechanism in addition to the regulation of the p38alpha and MK2 phosphorylation states that prevents phosphorylation of substrates in the absence of cell stress. Addition of constitutively active MKK6-DD results in rapid phosphorylation of the p38alpha-MK2 heterodimer.     

Specific targeting of a DNA-binding protein to the SPP1 procapsid by interaction with the portal oligomer

The icosahedral procapsid of tailed bacteriophages is composed of a large number of identical subunits and of minor proteins found in a few copies. Proteins present in a very low copy number are targeted to the viral procapsid by an unknown mechanism. Bacteriophage SPP1 procapsids and mature virions contain two copies of gp7 on average. Gp7 forms stable complexes with the SPP1 portal protein gp6. Deletion of the gp6 carboxyl-terminus and the mutation Y467-->C localized in the same region prevent gp6-gp7 complex formation. Gp7 binds double-stranded and single-stranded DNA. Gp6 competes for this interaction, and purified gp6-gp7 complexes do not bind DNA. Procapsid structures assembled in the absence of gp6 or carrying the mutant gp6 Y467-->C lack gp7. The gp6-gp7 interaction thus targets gp7 to the procapsid where the portal protein is localized asymmetrically at a single vertex of the icosahedral structure. The interaction between the two proteins is disrupted during viral assembly. Proteins homologous to gp6 and gp7 are coded by contiguous genes in a variety of phage genomes from Gram-positive bacteria, suggesting that the gp6-gp7 complex is widespread in this group of phages. Transient association with the portal protein, an essential component of tailed bacteriophages and herpes viruses, provides a novel strategy to target minor proteins to the virion structure that might be operative in a large number of viruses.     

Molecular characterization of pig muscle phosphoglucose isomerase

As a corollary to X-ray crystallographic work performed by H. Muirhead, detailed studies on crystalline pig muscle phosphoglucose isomerase have been conducted to establish its basic physical and chemical properties. The enzyme species being investigated by X-ray diffraction has been determined to be isoenzyme III. Its molecular weight in the native state was found to be 132,000, its s⁰₂₀,w value to be 7·25 S. The enzyme is composed of two subunits of equal molecular weight (66,000). Its amino acid composition is largely similar to that of rabbit muscle phosphoglucose isomerase, with the significant exception that the pig muscle isomerase contains only three sulfhydryl groups per polypeptide chain (two of them accessible to titration with p-mercuribenzoate) as compared with twice that number for the rabbit muscle enzyme. This low number of sulfhydryl groups is interpreted as being responsible for the ease with which heavy-atom, isomorphous derivatives could be prepared for the pig muscle enzyme by Shaw & Muirhead (1977).