Purification, quaternary structure and immunological properties of phosphorylase kinase from chicken skeletal muscle

Phosphorylase kinase was isolated from red and white chicken skeletal muscle in a nearly homogeneous state as judged by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate. The molecular weight of the native enzyme as determined by gel filtration on Sepharose 4B is close to that of rabbit skeletal muscle phosphorylase kinase (i. e., approximately 1300 000). The molecular weights of the subunits determined by SDS gel electrophoresis are: alpha', 140 000 beta, 129 000; gamma', 44 000; delta, 17 000 (cf. the Mr values of the alpha- and gamma-subunits of the rabbit muscle isoenzyme are 146 000 and 42 000). The four subunits, alpha', beta, gamma' and delta, were found to exist in equimolar amounts as shown by a densitometric analysis of acrylamide gels; hence, the subunit formula of the chicken skeletal muscle isoenzyme is (alpha' beta gamma' delta)4. Rabbit antisera against a mixture of alpha'- and beta-subunits of chicken phosphorylase kinase yield a single precipitin line with this enzyme, do not show cross reactions of identity with the rabbit muscle enzyme but strongly inhibit the activity of the chicken enzyme and partially inhibit the activity of the rabbit muscle isoenzyme.     

Effect of anti-mosquito antibodies on the infectivity of the rodent malaria parasite Plasmodium berghei to Anopheles farauti

The effect of mouse anti-mosquito antibodies, present in the bloodmeal, on the infectivity of Plasmodium berghei Vincke to Anopheles farauti Laveran was investigated. Significantly fewer oocysts developed in mosquitoes feeding on mice immunized with sugar-fed mosquito midgut antigens than in mosquitoes feeding on control mice. Mosquitoes feeding on mice immunized with the midgut antigens derived from sugar-fed mosquitoes also showed reduced mortality and had lower infection rates than those fed on unimmunized mice. Blood-fed midgut antigen was less effective in producing these effects than sugar-fed midgut antigen.     

Improved Dot-Blot Hybridization Assay for Large-Scale Detection of Potato Viruses in Crude Potato Tuber Extracts

Abstract A rapid and simple technique has been developed to enhance the sensitivity of virus detection in dot-blot hybridization assay by up to 1000 fold. The procedure generally follows that of B aulcombe et al. (1984) but includes moderate heating of the nitrocellulose filter in 10XSSC, 0.5% SDS solution at 55°C after sample application. Using this procedure, four potato viruses (PVX, PVS, PVM and PVY) were detected with cloned virus-specific ³²P-cDNA probes in 2 μl spots containing 0.2–2 pg of purufied virus (0.1–1 ng/ml). The procedure was also successfully applied for the detection of PVX, PVS, PVM and PVY in crude potato tuber extracts.     

Chemico-enzymatic synthesis and cloning of human angiogenin gene in M13mp8 phage

The nucleotide sequence coding for human angiogenin has been deduced from the published amino acid sequence with the use of codons preferentially utilized in highly expressed E. coli genes. It was divided into forty-three oligonucleotides, which were synthesized by automatic gene assembler and then joined by DNA ligase into three double-stranded blocks, the blocks were consequently cloned and ligated in M13mp8 phage, and the resultant 389-bp DNA sequence coding for human angiogenin was analysed by chain-terminator sequencing technique.     

Molecular biology of wound-inducible proteinase inhibitors in plants

Abstract. The techniques of molecular biology are being employed to investigate at the gene level the systemically mediated, wound-induced accumulation of two defensive proteinase inhibitor proteins in plant leaves. These techniques have added a new dimension to biochemical and physiological studies already underway to understand the mechanism of induction by wounding. The acquisition of cDNAs from the RNAs coding for the two inhibitors facilitated studies of mRNA synthesis in leaves in response to wounding, and provided probes to obtain wound-inducible proteinase inhibitor genes from tomato ( Lycopersicon esculentum ) and potato (Solarium tuberosum) genomes. Successful transformations of tobacco plants with fused genes, containing the 5' and 3' regions of the inhibitor genes with the open reading frame of the chloramphenicol acelyltransferase ( cat ) gene, have provided a wound-inducible chloramphenicol acetyltransferase (CATase) activity with which to seek cis- and transacting elements that regulate wound-inducibility to help to understand the interaction of cytoplasmic and nuclear components of the intracellular communication systems that activate the proteinase inhibitor genes in response to wounding by insect pests.     

Structural and functional analysis of the respiratory burst in the phagocytosing macrophage

The interrelation between structural changes and oxygen consumption by the phagocyting macrophage was studied. The mean number of phagocyted particles was estimated by the method of stereological transformation. It is found that the uptake of yeast particles and CN- -nonsensitive oxygen consumption is related to the concentration of yeast cells in the incubation medium. A positive correlation was established between the oxygen consumption and the mean number of phagocyted particles. The results obtained may suggest that the "respiration burst" takes place in the contact area of the macrophage and the phagocyted material, and its extent probably depends on the surface of that contact area.     

A-like cells of the gastric mucosa as a possible source of prostaglandins

AL cells of the oxyntic stomach area were studied in rats using ultrastructurometric technique. High-threshold, short-term direct electrical vagostimulation (5 V, 4 msec, 30 Hz, 10 sec) was performed in experimental group of 12 animals. Animals were killed 1, 10 and 30 min after stimulation. High post-stimulation lipolytic activity of AL cells and intensification of "granule autophagy" phenomenon were noted. Our findings as well as the literature data suggest a hypothesis on possible prostaglandin production by AL cells. Direct evidence in favour of this hypothesis is difficult to obtain due to the lack of sufficiently reliable methods of their morphological detection in cells.     

Immunoenzyme detection of specific brain antigens as a criterion of the permeability of the hemato-encephalic barrier in rats following acute gamma irradiation

The immunoenzyme detection systems for the measurement of the alpha-2 globulin of the brain (alpha 2M) and glial fibrillary acidic antigens (GFAP) were developed. These systems were used for the study of the penetration through hemato-encephalic barrier in rats subjected to gamma radiation. This method is recommended for the indirect evaluation of the hemato-encephalic barrier functional disorders.     

吗啡耐受大鼠心房心钠素的释放及其基因转录

本工作应用心钠素放射免疫测定和分子杂交技术首次发现,吗啡耐受大鼠血浆心钠素水平显著降低,心房内心钠素含量明显升高,同时心房内心钠素特异性mRNA水平也相应提高,提示在吗啡耐受时大鼠心房内心钠素的合成和贮存增加,释放减少。