scholarly journals Cloning and expression of two ornithine decarboxylase forms from HMOA cells

1995 ◽  
Vol 312 (1) ◽  
pp. 13-16
Author(s):  
R Autelli ◽  
L Persson ◽  
F M Baccino

In HMOA cells [Mamont, Duchesne, Grove and Tardif (1978) Exp. Cell Res. 115, 387-393] the half-life of ornithine decarboxylase (ODC) is 8-14 h instead of 15 min as in the Hepatoma Tissue Culture parental cells, due to a single amino acid substitution [Miyazaki, Matsufuji, Murakami and Hayashi (1993) Eur. J. Biochem. 214, 837-844]. We demonstrate for the first time that HMOA cells possess two forms of ODC mRNA that are translated into two proteins differing greatly in turnover rates. We have cloned and transfected the cDNAs for the two ODC forms into COS-1 cells for a direct measurement of their turnover rate. The variant ODC form was much more stable than the wild-type protein, with a half-life of 14 h as compared with 2.5 h.

Blood ◽  
1961 ◽  
Vol 18 (6) ◽  
pp. 710-716 ◽  
Author(s):  
AARON R. RAUSEN ◽  
ANDRE CRUCHAUD ◽  
CAMPBELL W. McMILLAN ◽  
DAVID GITLIN

Abstract The rate of disappearance from the plasma of intravenously administered I131-labeled fibrinogen was studied in six patients with classical hemophilia and in one patient with congenital afibrinogenemia. The six patients with hemophilia had radioiodinated fibrinogen half-lives ranging from 2.8 to 3.6 days, while the patient with congenital afibrinogenemia had a labeled fibrinogen half-life of 3.0 days. These results compare favorably with fibrinogen turnover rates measured in normal adults by others and were similar to the normal fibrinogen turnover rate determined in the patient with congenital afibrinogenemia in a previous study. This failure to demonstrate a prolongation of survival of fibrinogen in patients with hemophilia suggests that in vivo clotting, if it occurs at all normally, is not a major factor in the turnover of fibrinogen.


1993 ◽  
Vol 295 (1) ◽  
pp. 305-308 ◽  
Author(s):  
Y Murakami ◽  
S Matsufuji ◽  
K Tanaka ◽  
A Ichihara ◽  
S Hayashi

Ornithine decarboxylase (ODC) degradation in a freshly prepared reticulocyte lysate was examined. Immunodepletion of proteasomes from the reticulocyte lysate resulted in almost complete loss of ODC degradation. In contrast with the previously reported degradation in extracts of hepatoma tissue-culture (HTC) and Chinese-hamster ovary (CHO) cells or that by the purified 26 S proteasome, efficient degradation of ODC was observed in the lysate without exogenous antizyme, an ODC protein inhibitor induced by polyamines, owing to the presence of a significant amount of antizyme in the lysate. The degradation of ODC in the lysate was strongly suppressed on inactivation of antizyme in the lysate with antizyme inhibitor, a protein which binds to the antizyme and releases ODC from the ODC-antizyme complex. Thus the main pathway for ODC degradation in a reticulocyte lysate was essentially the same as that characterized previously in extracts of HTC and CHO cells, namely an ATP- and antizyme-dependent 26 S proteasome-catalysed pathway that is presumed to be responsible for ODC degradation in whole cells.


1968 ◽  
Vol 19 (1) ◽  
pp. 129
Author(s):  
PH Springell

Twenty-four steers, comprising British (Hereford and Hereford x Shorthorn), Zebu (Africander), and Zebu cross (British x Brahman or Africander) breeds, were either maintained on pasture, or yarded and fed on diets of a low and a high nutritional value. Tritiated water was injected into the animals on five occasions at intervals of 3 months. The body water content and the water turnover rate were calculated, and some of the sources of variation defined. Observed differences in the water content are attributable to nutritional factors rather than to breed differences. The mean body water content ranged from 615 to 809 ml/kg fasting body weight, where the higher values were associated with a poor diet. The mean half-life of tritiated water was lower in summer (as low as 58 hr) than in winter (up to 128 hr) in grazing and well-fed yarded steers. On a poor diet, however, the half-life in yarded cattle remained high and almost constant throughout the year, dropping to below 100 hr on only a single occasion. Occasionally the half-life was breed dependent, but generally no significant differences between breeds could be found. While mean turnover rates of up to 7.1 ml kg-1 hr-1 were found in better-fed cattle in summer, the value in poorly fed animals was almost constant throughout the year at about 3.3 ml kg-1 hr-1. There was, however, a winter minimum in the well-fed yarded and grazing groups. The turnover rate was also influenced by breed only to a limited extent. The results are interpreted in the light of their possible significance in the adaptation to a tropical environment, and in relation to their value in predicting the body composition.


1958 ◽  
Vol 194 (3) ◽  
pp. 446-452 ◽  
Author(s):  
Margaret W. Bates

The half-life times of plasma phospholipid and nonphospholipid fatty acids were determined in postabsorptive dogs using C14-carboxyl-labeled palmitic acid. Labeled plasma lipids were introduced into the blood of a recipient dog by cross-circulation with a donor dog that had been fed the radioactive palmitic acid 24 hours previously. Blood samples were taken at various time intervals after the cross-circulation was completed. When the specific activity of the nonphospholipid fatty acids was plotted against time, a semilogarithmic curve was obtained that was resolved into two exponential components with mean half-life times of 22.3 ± 21.9 (S.D.) and 905 ± 182 (S.D.) minutes. A half-life time of 327 ± 81 (S.D.) minutes was found for the phospholipid fatty acids. In one experiment the nonphospholipid fat was further fractionated chromatographically into triglycerides and cholesterol esters. The half-life times of the fatty acids of these two fractions were comparable to the values obtained for the fast and slow components, respectively, found in the preceding experiments. The turnover rate of the triglyceride fatty acids was 1502 ± 505 (S.D.) mg/hr. The rate of appearance of the cholesterol ester fatty acids into the plasma was 29.0 ± 32.7 (S.D.) mg/hr.; the rate of disappearance, 63.4 ± 38.0 (S.D.) mg/hr. A turnover rate of 125.2 ± 49.2 (S.D.) mg/hr. was found for the phospholipid fatty acids in the earlier experiments. The large turnover rate of the plasma triglyceride fatty acids strongly suggests that this fraction is important in the transport of fatty acids in the postabsorptive dog.


1985 ◽  
Vol 225 (3) ◽  
pp. 689-697 ◽  
Author(s):  
Y Murakami ◽  
K Fujita ◽  
T Kameji ◽  
S Hayashi

A new method was developed for the assay of ornithine decarboxylase (ODC)-antizyme complex, in which alpha-difluoromethylornithine (DFMO)-inactivated ODC was used to release active ODC competitively from the complex. ODC-antizyme complex was present in the extracts of hepatoma tissue-culture (HTC) cells and of ODC-stabilized variant HMOA cells, in much larger amounts in the latter. Cellular amounts of the complex fluctuated after a change of medium in a similar manner in HTC and HMOA cells, increasing during the period of ODC decay. After treatment with cycloheximide, the decay of ODC-antizyme complex in HMOA cells was more rapid than the decay of free ODC, but it was much slower than the decay of free ODC or complexed ODC in HTC cells. Administration of putrescine caused a rapid increase in the amount of ODC-antizyme complex in both HTC and HMOA cells, but nevertheless the decay of total ODC (free ODC plus ODC-antizyme complex) was more rapid with putrescine than with cycloheximide. These results suggested the possibility that ODC is degraded through complex-formation with antizyme. In contrast with complexed antizyme, free antizyme was not stabilized in HMOA cells.


eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Fernanda Bajanca ◽  
Vinicio Gonzalez-Perez ◽  
Sean J Gillespie ◽  
Cyriaque Beley ◽  
Luis Garcia ◽  
...  

Dystrophin forms an essential link between sarcolemma and cytoskeleton, perturbation of which causes muscular dystrophy. We analysed Dystrophin binding dynamics in vivo for the first time. Within maturing fibres of host zebrafish embryos, our analysis reveals a pool of diffusible Dystrophin and complexes bound at the fibre membrane. Combining modelling, an improved FRAP methodology and direct semi-quantitative analysis of bleaching suggests the existence of two membrane-bound Dystrophin populations with widely differing bound lifetimes: a stable, tightly bound pool, and a dynamic bound pool with high turnover rate that exchanges with the cytoplasmic pool. The three populations were found consistently in human and zebrafish Dystrophins overexpressed in wild-type or dmdta222a/ta222a zebrafish embryos, which lack Dystrophin, and in Gt(dmd-Citrine)ct90a that express endogenously-driven tagged zebrafish Dystrophin. These results lead to a new model for Dystrophin membrane association in developing muscle, and highlight our methodology as a valuable strategy for in vivo analysis of complex protein dynamics.


Blood ◽  
1965 ◽  
Vol 25 (5) ◽  
pp. 683-692 ◽  
Author(s):  
PETER R. GALBRAITH ◽  
LESLIE S. VALBERG ◽  
MALCOLM BROWN

Abstract Leukokinetic studies were performed using granulocytes labeled in vitro with radioactive diisopropylfluorophosphate (DFP32). The half-time of the granulocytes in the circulation, blood granulocyte mass and granulocyte turnover rates were determined. In control subjects the mean half-life was 6.44 hours with a range of 5.1 to 7.7 hours. The mean blood granulocyte mass was 38 x 109 cells with a range of 19.9 to 36.4 x 109 cells and the granulocyte turnover rate was 4.08 x 109 cells per hour with a range of 2.51 to 5.50 x 109 cells per hour. There was a direct relationship between the half-life and the blood granulocyte mass in the control subjects. In 6 subjects with infection the blood granulocyte mass was uniformly increased. The mean half-life and mean granulocyte turnover rate were both increased above the normal range. In 11 subjects with carcinoma several different leukokinetic patterns were found. The blood granulocyte mass was raised in 5 patients, but in only one of these was the granulocyte turnover rate increased above the normal range. In 6 subjects the blood granulocyte mass was within the normal range and deviations from the mean control value were accompanied by proportionate changes in the granulocyte turnover rate in all but 1 patient. No relation was found between the half-life and the blood granulocyte mass in subjects with infection and/or carcinoma. The possibility that this was due to the establishment of a new steady state of blood granulocyte mass at altered levels of granulocyte production, or that steady state conditions did not exist has been considered. However the data are interpreted no evidence for suppressed granulopoiesis was found in subjects with advanced malignant disease.


1968 ◽  
Vol 19 (1) ◽  
pp. 129
Author(s):  
PH Springell

Twenty-four steers, comprising British (Hereford and Hereford x Shorthorn), Zebu (Africander), and Zebu cross (British x Brahman or Africander) breeds, were either maintained on pasture, or yarded and fed on diets of a low and a high nutritional value. Tritiated water was injected into the animals on five occasions at intervals of 3 months. The body water content and the water turnover rate were calculated, and some of the sources of variation defined. Observed differences in the water content are attributable to nutritional factors rather than to breed differences. The mean body water content ranged from 615 to 809 ml/kg fasting body weight, where the higher values were associated with a poor diet. The mean half-life of tritiated water was lower in summer (as low as 58 hr) than in winter (up to 128 hr) in grazing and well-fed yarded steers. On a poor diet, however, the half-life in yarded cattle remained high and almost constant throughout the year, dropping to below 100 hr on only a single occasion. Occasionally the half-life was breed dependent, but generally no significant differences between breeds could be found. While mean turnover rates of up to 7.1 ml kg-1 hr-1 were found in better-fed cattle in summer, the value in poorly fed animals was almost constant throughout the year at about 3.3 ml kg-1 hr-1. There was, however, a winter minimum in the well-fed yarded and grazing groups. The turnover rate was also influenced by breed only to a limited extent. The results are interpreted in the light of their possible significance in the adaptation to a tropical environment, and in relation to their value in predicting the body composition.


1988 ◽  
Vol 8 (2) ◽  
pp. 531-539 ◽  
Author(s):  
C A Finlay ◽  
P W Hinds ◽  
T H Tan ◽  
D Eliyahu ◽  
M Oren ◽  
...  

The 11-4 p53 cDNA clone failed to transform primary rat fibroblasts when cotransfected with the ras oncogene. Two linker insertion mutations at amino acid 158 or 215 (of 390 amino acids) activated this p53 cDNA for transformation with ras. These mutant cDNAs produced a p53 protein that lacked an epitope, recognized by monoclonal antibody PAb246 (localized at amino acids 88 to 110 in the protein) and preferentially bound to a heat shock protein, hsc70. In rat cells transformed by a genomic p53 clone plus ras, two populations of p53 proteins were detected, PAb246+ and PAb246-, which did or did not bind to this monoclonal antibody, respectively. The PAb246- p53 preferentially associated with hsc70, and this protein had a half-life 4- to 20-fold longer than free p53 (PAb246+). These data suggest a possible functional role for hsc70 in the transformation process. cDNAs for p53 derived from methylcholanthrene-transformed cells transform rat cells in cooperation with the ras oncogene and produce a protein that bound with the heat shock proteins. Recombinant clones produced between a Meth A cDNA and 11-4 were tested for the ability to transform rat cells. A single amino acid substitution at residue 132 was sufficient to activate the 11-4 p53 cDNA for transformation. These studies have identified a region between amino acids 132 and 215 in the p53 protein which, when mutated, can activate the p53 cDNA. These results also call into question what the correct p53 wild-type sequence is and whether a wild-type p53 gene can transform cells in culture.


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