Postfusion incompatibility in Physarum polycephalum: changes in protein pattern of a heterokaryon

1985 ◽  
Vol 31 (9) ◽  
pp. 778-781 ◽  
Author(s):  
J. A. M. Schrauwen
Keyword(s):  
Protein Synthesis ◽  
Physarum Polycephalum ◽  
Protein Pattern ◽  
Two Dimensional ◽  
Polypeptide Patterns ◽  
Lethal Reaction ◽  
Different Strains

The polypeptide patterns of two different strains of Physarum polycephalum, sensitive and killer, showed only minor differences on two-dimensional electrophoretograms. After heterologous fusion of the sensitive and killer plasmodia, newly formed proteins could be demonstrated which were not detectable in homologous fused plasmodia. The lethal reaction did not occur until after the aforementioned protein synthesis.

Changes in patterns of protein synthesis in axolotl oocytes during progesterone-induced maturation

Development ◽  
1986 ◽  
Vol 92 (1) ◽  
pp. 103-113
Author(s):  
Jean Gautier ◽  
Renée Tencer
Keyword(s):  
Protein Synthesis ◽  
Protein Phosphorylation ◽  
Cholera Toxin ◽  
Oocyte Maturation ◽  
Gel Electrophoresis ◽  
De Novo ◽  
Protein Pattern ◽  
Ambystoma Mexicanum ◽  
Two Dimensional ◽  
Two Dimensional Gel Electrophoresis

Patterns of protein phosphorylation and synthesis during axolotl (Ambystoma mexicanum) oocyte maturation were studied by incorporation of [32P]orthophosphate and [35S]methionine into polypeptides, followed by two-dimensional gel electrophoresis. Various alterations were observed after progesterone treatment: de novo appearance of [35S]methionine-labelled polypeptides, a quantitative increase in previously synthesized proteins and a quantitative decrease in or disappearance of other previously synthesized proteins. Changes in 32P- and 35S-labelling were observed very early during maturation. Neither prior oocyte enucleation nor α-amanitin treatment had a significant effect on these changes. Stimulation with MPF provided the same final protein pattern as PG treatment. However, cholera toxin inhibited all the changes seen during maturation. Comparisons between the patterns of [35S]methionine- and [32P]phosphatelabelling provide further information on the biochemical events that take place during oocyte maturation.

scholarly journals An immunological approach to enrich a mitotic stimulator and to reveal G2-phase-specific proteins in Physarum polycephalum.

1985 ◽  
Vol 100 (6) ◽  
pp. 1930-1933 ◽  
Author(s):  
P Gröbner ◽  
P Loidl
Keyword(s):  
Physarum Polycephalum ◽  
Protein Pattern ◽  
Protein A ◽  
S Phase ◽  
Two Dimensional ◽  
Two Dimensional Gel Electrophoresis ◽  
Immunological Approach ◽  
Before And After ◽  
Specific Proteins ◽  
G2 Phase

Purified antibodies from an antiserum against S-phase proteins of the myxomycete Physarum polycephalum were attached to protein-A-Sepharose CL-4B. A late G2-phase extract that contained a mitosis-stimulating protein was applied to this immunoadsorbent, and the mitosis-stimulating protein was enriched by a factor of ten. This protein, which is present in the cell in low amounts, is synthesized in late G2 phase and obviously degraded in a later stage of the cycle. Immunoadsorption of a G2-phase extract with anti-S-antibodies decreased the 700 main proteins to 20 as demonstrated by two-dimensional gel electrophoresis. No difference in protein pattern could be observed on two-dimensional gels between S-phase and G2-phase extracts before and after immunoadsorption with anti-S-antibodies. This indicates that there are no G2-phase-specific proteins among the 700 most abundant proteins of Physarum polycephalum.

Two-dimensional gel electrophoresis of serum specimens from a normal population.

1982 ◽  
Vol 28 (4) ◽  
pp. 890-899 ◽  
Author(s):  
R P Tracy ◽  
R M Currie ◽  
D S Young
Keyword(s):  
Gel Electrophoresis ◽  
Serum Proteins ◽  
Protein Pattern ◽  
Normal Population ◽  
Small Samples ◽  
Two Dimensional ◽  
Silver Stain ◽  
Two Dimensional Gel Electrophoresis ◽  
Finger Stick ◽  
Effects Of Aging

Abstract We examined sera from a normal population by two-dimensional gel electrophoresis, to establish the normal pattern of serum proteins and to investigate genetic polymorphisms. With such information in hand, specimens from patients with certain diseases may be readily evaluated. Towards this goal, we optimized the ISO-DALT system (Proc. Natl, Acad, Sci, USA 74: 5421--5425, 1977) for routine phenotyping of alpha 1-antitrypsin, haptoglobin, GC-globulin, alpha 2-HS-glycoprotein, and transferrin, as well as a previously unknown polymorphic protein. We examined the effects of aging the specimens for 2 h at room temperature (no changes) or at -20 degrees C for several months (small changes), as well as serum/plasma differences and the effect of protease inhibitors. Silver-stain methods were modified to allow simultaneous staining of 10 gels, with reasonably good reproducibility of stain intensity. We quantitated silver-stained gels by densitometry of photographic transparencies. Very small samples suffice with this stain (0.5 microL of serum or plasma), allowing the use of "finger-stick" methods instead of venipuncture, yet the patterns are better resolved and easier to read than those for 10-microL specimens processed on gels stained with Coomassie Blue. Our techniques for rapidly removing albumin and IgG allow the investigator to examine areas on the gel that ordinarily are obscured. The region of haptoglobin has been examined by using serum from an ahaptoglobinemic donor. Finally, we present an expanded "normal" map illustrating the composite protein pattern.

In vivo levels of diadenosine tetraphosphate and adenosine tetraphospho-guanosine in Physarum polycephalum during the cell cycle and oxidative stress

1986 ◽  
Vol 6 (4) ◽  
pp. 1179-1186
Author(s):  
P N Garrison ◽  
S A Mathis ◽  
L D Barnes
Keyword(s):  
Oxidative Stress ◽  
Cell Cycle ◽  
Physarum Polycephalum ◽  
Fold Increase ◽  
Luciferase Assay ◽  
Diadenosine Tetraphosphate ◽  
Liquid Chromatographic Method ◽  
Different Strains ◽  
Liquid Chromatographic

Cellular levels of diadenosine tetraphosphate (Ap4A) and adenosine tetraphospho-guanosine (Ap4G) were specifically measured during the cell cycle of Physarum polycephalum by a high-pressure liquid chromatographic method. Ap4A was also measured indirectly by a coupled phosphodiesterase-luciferase assay. No cell cycle-specific changes in either Ap4A or Ap4G were detected in experiments involving different methods of assay, different strains of P. polycephalum, or different methods of fixation of macroplasmodia. Our results on Ap4A are in contrast with those reported previously (C. Weinmann-Dorsch, G. Pierron, R. Wick, H. Sauer, and F. Grummt, Exp. Cell Res. 155:171-177, 1984). Weinmann-Dorsch et al. reported an 8- to 30-fold increase in Ap4A in early S phase in P. polycephalum, as measured by the phosphodiesterase-luciferase assay. We also measured levels of Ap4A, Ap4G, and ATP in macroplasmodia treated with 0.1 mM dinitrophenol. Ap4A and Ap4G transiently increased three- to sevenfold after 1 h and then decreased concomitantly with an 80% decrease in the level of ATP after 2 h in the presence of dinitrophenol. These results do not support the hypothesis that Ap4A is a positive pleiotypic activator that modulates DNA replication, but they are consistent with the hypothesis proposed for procaryotes that Ap4A and Ap4G are signal nucleotides or alarmones of oxidative stress (B.R. Bochner, P.C. Lee, S.W. Wilson, C.W. Cutler, and B.N. Ames, Cell 37:225-232, 1984).

Two-dimensional gel electrophoresis of human brain proteins. I. Technique and nomenclature of proteins.

1982 ◽  
Vol 28 (4) ◽  
pp. 782-789 ◽  
Author(s):  
D E Comings
Keyword(s):  
Human Brain ◽  
Gel Electrophoresis ◽  
Urea Solution ◽  
Two Dimensional ◽  
Two Dimensional Gel Electrophoresis ◽  
Polypeptide Patterns ◽  
Normal Individuals ◽  
Molecular Masses ◽  
Group B ◽  
The Individual

Abstract To understand at a molecular level the basis of the normal and pathological genetic differences between individuals it is necessary to begin a detailed two-dimensional gel electrophoretic mapping of the proteins of the human brain in normal individuals and those with various genetic neurological disorders. The present study is an examination of the polypeptide patterns of extracts of the human brain made with 9 mol/L urea solution. Details of the technique and the nomenclature of the patterns obtained are presented. the gels are separated into 20 sub-sections, based on standards with known molecular masses and isoelectric points. Groups of polypeptides within these sub-sections are identified by a number and a letter; the individual proteins are identified by a number. Thus, protein 1 in subsection 8, group b, would be designated 8b: 1. Subsequent papers in this series identify many of these proteins; show which proteins belong to the cytosol, synaptosome, myelin, and other brain fractions; show how these patterns vary between normal individuals and those with different neurological and psychiatric conditions; examine the effect of severe gliosis; and present the results of non-equilibrium gel electrophoresis for the more basic proteins.

scholarly journals LIMITED DNA SYNTHESIS IN THE ABSENCE OF PROTEIN SYNTHESIS IN PHYSARUM POLYCEPHALUM

1966 ◽  
Vol 31 (3) ◽  
pp. 577-583 ◽  
Author(s):  
J. E. Cummins ◽  
H. P. Rusch
Keyword(s):  
Protein Synthesis ◽  
Dna Replication ◽  
Dna Synthesis ◽  
Physarum Polycephalum ◽  
Nuclear Dna ◽  
S Phase ◽  
Early Prophase ◽  
Late Prophase ◽  
Removal Experiments ◽  
Inhibitor Of Protein Synthesis

Actidione (cycloheximide), an antibiotic inhibitor of protein synthesis, blocked the incorporation of leucine and lysine during the S phase of Physarum polycephalum. Actidione added during the early prophase period in which mitosis is blocked totally inhibited the initiation of DNA synthesis. Actidione treatment in late prophase, which permitted mitosis in the absence of protein synthesis, permitted initiation of a round of DNA replication making up between 20 and 30% of the unreplicated nuclear DNA. Actidione treatment during the S phase permitted a round of replication similar to the effect at the beginning of S. The DNA synthesized in the presence of actidione was replicated semiconservatively and was stable through at least the mitosis following antibiotic removal. Experiments in which fluorodeoxyuridine inhibition was followed by thymidine reversal in the presence of actidione suggest that the early rounds of DNA replication must be completed before later rounds are initiated.

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