The effect of removal of the frontal ganglion on growth and protein synthesis in young adults of Locusta migratoria

1974 ◽  
Vol 52 (2) ◽  
pp. 203-208 ◽  
Author(s):  
D. E. Bignell
Keyword(s):  
Young Adults ◽  
Protein Synthesis ◽  
Fat Body ◽  
Locusta Migratoria ◽  
Growth Arrest ◽  
Stomatogastric Nervous System ◽  
Food Passage ◽  
Frontal Ganglion

Removal of the Frontal ganglion in young adult locusts results in growth arrest, disruption of food passage in the gut, reduced faecal out put, and a high mortality. The effects of the operation in young adults differ in degree from those observed in larvae.An in vitro incubation technique was used to make a quantitative estimate of protein synthesis in the fat body after frontal ganglion removal and starvation. A significant reduction of protein synthesis after frontal ganglion removal was observed.The results are discussed in relation to the role of the stomatogastric nervous system in controlling food passage in the gut and the release of neurohormone from the corpora cardiaca.

Studies on the Effects of the Removal of the Frontal Ganglion in Locusta Migratoria L

1967 ◽  
Vol 46 (1) ◽  
pp. 27-34
Author(s):  
KENNETH U. CLARKE ◽  
CEDRIC GILLOTT
Keyword(s):  
Protein Synthesis ◽  
Dna Content ◽  
Fat Body ◽  
Locusta Migratoria ◽  
Fourth Instar ◽  
Monod Model ◽  
Cytoplasmic Rna ◽  
Cytochemical Investigation ◽  
Frontal Ganglion ◽  
And Control

1. A cytochemical investigation was made of the RNA content of the cells of the mid-gut, fat body and epidermis in third- and fourth-instar Locusta migratoria L. from which the frontal ganglion had been removed, in control operated and in starved animals. In operated locusts the nucleus was smaller, the nucleoli small or absent, and the cytoplasmic RNA much less than that found in operated controls. No differences were observed in the DNA content of the cells. 2. Autoradiograph studies were made of the uptake of 3H-uridine into the cells of operated and control operated locusts. In operated locusts the appearance of labelled uridine in the nucleus was delayed, the rate of uptake slower, and the total amount incorporated less (never more than 25%) than in the controls. 3. Studies were made of the uptake of 14C-uridine into the nuclei of operated and control-operated locusts. Nuclei were isolated from locusts killed at known times after the isotope had been injected and their radioactivity was measured. The results confirmed those found in the radioautographic studies. 4. The significance of these results is considered in the light of the Jacob & Monod model of the control of protein synthesis.

Activation of bovine oocytes by protein synthesis inhibitors: new findings on the role of MPF/MAPKs†

2021 ◽  
Author(s):  
Cecilia Valencia ◽  
Felipe Alonso Pérez ◽  
Carola Matus ◽  
Ricardo Felmer ◽  
María Elena Arias
Keyword(s):  
Protein Synthesis ◽  
Kinase Activity ◽  
Cyclin B1 ◽  
Protein Synthesis Inhibitors ◽  
Vitro Fertilization ◽  
New Findings ◽  
Bovine Oocytes ◽  
Dependent Pathway

Abstract The present study evaluated the mechanism by which protein synthesis inhibitors activate bovine oocytes. The aim was to analyze the dynamics of MPF and MAPKs. MII oocytes were activated with ionomycin (Io), ionomycin+anisomycin (ANY) and ionomycin+cycloheximide (CHX) and by in vitro fertilization (IVF). The expression of cyclin B1, p-CDK1, p-ERK1/2, p-JNK, and p-P38 were evaluated by immunodetection and the kinase activity of ERK1/2 was measured by enzyme assay. Evaluations at 1, 4, and 15 hours postactivation (hpa) showed that the expression of cyclin B1 was not modified by the treatments. ANY inactivated MPF by p-CDK1Thr14-Tyr15 at 4 hpa (P < 0.05), CHX increased pre-MPF (p-CDK1Thr161 and p-CDK1Thr14-Tyr15) at 1 hpa and IVF increased p-CDK1Thr14-Tyr15 at 17 hours postfertilization (hpf) (P < 0.05). ANY and CHX reduced the levels of p-ERK1/2 at 4 hpa (P < 0.05) and its activity at 4 and 1 hpa, respectively (P < 0.05). Meanwhile, IVF increased p-ERK1/2 at 6 hpf (P < 0.05); however, its kinase activity decreased at 6 hpf (P < 0.05). p-JNK in ANY, CHX, and IVF oocytes decreased at 4 hpa (P < 0.05). p-P38 was only observed at 1 hpa, with no differences between treatments. In conclusion, activation of bovine oocytes by ANY, CHX, and IVF inactivates MPF by CDK1-dependent specific phosphorylation without cyclin B1 degradation. ANY or CHX promoted this inactivation, which seemed to be more delayed in the physiological activation (IVF). Both inhibitors modulated MPF activity via an ERK1/2-independent pathway, whereas IVF activated the bovine oocytes via an ERK1/2-dependent pathway. Finally, ANY does not activate the JNK and P38 kinase pathways.

scholarly journals Protein Synthesis in Human Leukocytes and Lymphocytes: 1. Effect of Steroids and Sterols

Blood ◽  
1969 ◽  
Vol 34 (3) ◽  
pp. 348-356 ◽  
Author(s):  
SEYMOUR WERTHAMER ◽  
CARL HICKS ◽  
LEONARD AMARAL
Keyword(s):  
Protein Synthesis ◽  
Steroid Hormones ◽  
Plasma Protein ◽  
Human Lymphocytes ◽  
Amino Acid Incorporation ◽  
Binding Factor ◽  
In Vitro Effects ◽  
Physiologic Role

Abstract The in vitro effects of sterols, cholesterol and 3-methyl cholanthrene and steroids, cortisol, prednisolone and testosterone on protein synthesis in separate popultions of human lymphocytes and leukocytes has been investigated. It has been shown that all agents used result in the inhibition of protein synthesis under these conditions. It has also been shown that the inhibitory mechanism of the steroid hormones requires the presence of plasma, presumably as a protein binding factor in order to achieve its effect. The sterol, cholesterol and 3-methyl cholanthrene, in the absence of plasma, still inhibit amino acid incorporation. However, in the case of cholesterol, the magnitude of inhibition is lower than that observed in the presence of plasma, perhaps indicating a partial plasma dependence. The results presented therefore support the hypothesis that the inhibition of lymphocyte protein synthesis by steroid hormones occurs only when the steroid is bound to a plasma protein. The physiologic role of the plasma protein-cortisol complex and its relation to the condition of lymphopenia in man is discussed.

Heat-shock-induced grey crescent formation in axolotl eggs and oocytes: the role of gravity

Development ◽  
1987 ◽  
Vol 100 (4) ◽  
pp. 599-609
Author(s):  
J.-C. Beetschen ◽  
J. Gautier
Keyword(s):  
Protein Synthesis ◽  
Heat Shock ◽  
Synergistic Action ◽  
Nuclear Factor ◽  
Crescent Formation ◽  
Animal Pole ◽  
Grey Crescent ◽  
Cytoskeletal Structure

Axolotl eggs were heat shocked (36.8°C, 10min) inside their jelly layers. Heat shock (HS) was shown to induce the precocious appearance of a grey crescent (GC) in a number of eggs immediately after fertilization (Benford & Namenwirth, 1974). It was also demonstrated that this phenomenon occurs in fertilized or artificially activated eggs only when they are shocked within 11/2h after spawning. The GC forms still later in heated unfertilized, nonactivated eggs. The role of the jelly layers is considered to be mechanical: a proportion of eggs is maintained in a tilted position until the egg is able to orient animal pole upwards under the influence of gravity as a late consequence of activation. The jelly layers are not essential if the eggs are artificially tilted or rotated during HS. GC formation can also be induced in in vitro maturing oocytes, provided they are tilted during HS. Gravity thus plays an essential role in the cytoplasmic rearrangements leading to HS-induced GC formation. Our results indicate a synergistic action between heat and gravity in this process. The cytological appearance of the GC formed in those experiments is that of a ‘Born's crescent’ with a conspicuous ‘vitelline wall’ (Pasteels, 1964). When oocytes are enucleated before maturation, HS has no effect on GC formation. A nuclear factor is therefore essential, as has been demonstrated in early GC formation induced by inhibitors of protein synthesis. Finally, incorporation of amino acids into oocyte proteins appears to be rapidly inhibited by HS (from 5 min). However, we cannot conclude that GC formation is in fact triggered by inhibition of protein synthesis. It is also likely that HS disrupts cytoskeletal structure, hence facilitating cytoplasmic rearrangements. Nevertheless, these results are in agreement with the scheme we recently proposed for GC formation in the rotated axolotl oocyte (Gautier & Beetschen, 1985).

Inhibitory effect of β-ecdysone on protein synthesis by blowfly fat body in vitro

1979 ◽  
Vol 35 (11) ◽  
pp. 1449-1451 ◽  
Author(s):  
R. Pau ◽  
L. Levenbook ◽  
A. C. Bauer
Keyword(s):  
Protein Synthesis ◽  
Fat Body ◽  
Inhibitory Effect

Effect of enucleation on protein synthesis during maturation of bovine oocytes in vitro

1997 ◽  
Vol 9 (6) ◽  
pp. 603 ◽  
Author(s):  
J. C. Bell ◽  
L. C. Smith ◽  
R. Rumpf ◽  
A. K. Goff
Keyword(s):  
Protein Synthesis ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Germinal Vesicle ◽  
Uv Exposure ◽  
One Dimensional ◽  
Repair Mechanisms ◽  
Bovine Oocytes

The role of the nucleus in protein synthesis reprogramming during oocyte maturation was examined in immature or mature bovine oocytes, enucleated at the germinal vesicle (GV) stage or the metaphase II (MII) stage. Cumulusoocyte complexes (COCs) were denuded before or after maturationin vitro. Denuded oocytes were (i) enucleated at the GV or MII stage (after DNA staining and ultraviolet (UV) exposure), (ii) stained and exposed to UV but not enucleated, or (iii) used as controls. After treatment, oocytes were labelled for 4 h with35S-methionine or were matured for 24 h before labelling. GV- or MII- karyoplasts and small portions of cytoplasm (cytoplasts), removed during enucleation, were also labelled. Labelled oocytes, karyoplasts or cytoplasts were prepared for one-dimensional polyacrylamide gel electrophoresis. Incorporation of labelled methionine into oocyte protein was measured. Enucleation did not affect protein synthesis reprogramming, but incorporation of 35S-methionine in immature UV-stained oocytes was high-possibly due to nuclear repair mechanisms. Protein proles of GV- and MII- karyoplasts differed from those of immature and mature oocytes. In conclusion, normal protein synthesis reprogramming in the cytoplasm can occur in the absence of the nucleus, and specic proteins are synthesized in the nuclear region.

Role of germinal vesicle on protein synthesis in rat oocyte during in vitro maturation

1996 ◽  
Vol 43 (2) ◽  
pp. 228-235 ◽  
Author(s):  
Li Meng ◽  
Jean Rutledge ◽  
Ying Zhu ◽  
Gerald M. Kidder ◽  
Firouz Khamsi ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
In Vitro Maturation ◽  
Germinal Vesicle
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