Kinetics and calcium-specificity of polyamine uptake in carrot protoplasts

Amino Acids ◽  
1994 ◽  
Vol 6 (3) ◽  
pp. 301-309 ◽  
Author(s):  
F. Antognoni ◽  
P. Casali ◽  
R. Pistocchi ◽  
N. Bagni
Keyword(s):  
Polyamine Uptake ◽  
Carrot Protoplasts

Effect of auxins on spermidine uptake into carrot protoplasts

1991 ◽  
Vol 82 (1) ◽  
pp. 19-23 ◽  
Author(s):  
Malee Kanchanapoom ◽  
Fabiana Antognoni ◽  
Rossella Pistocchi ◽  
Nello Bagni
Keyword(s):  
Carrot Protoplasts

scholarly journals Overexpression of antizyme in the hearts of transgenic mice prevents the isoprenaline-induced increase in cardiac ornithine decarboxylase activity and polyamines, but does not prevent cardiac hypertrophy

2000 ◽  
Vol 350 (3) ◽  
pp. 645-653 ◽  
Author(s):  
Caroline A. MACKINTOSH ◽  
David J. FEITH ◽  
Lisa M. SHANTZ ◽  
Anthony E. PEGG
Keyword(s):  
Transgenic Mice ◽  
Ornithine Decarboxylase ◽  
Prolonged Exposure ◽  
Constitutive Expression ◽  
Decarboxylase Activity ◽  
Cardiac Growth ◽  
Polyamine Content ◽  
Transgenic Lines ◽  
Response To Stress ◽  
Polyamine Uptake

Two lines of transgenic mice were produced with constitutive expression of antizyme-1 in the heart, driven from the cardiac α-myosin heavy chain promoter. The use of engineered antizyme cDNA in which nucleotide 205 had been deleted eliminated the need for polyamine-mediated frameshifting, normally necessary for translation of antizyme mRNA, and thus ensured the constitutive expression of antizyme. Antizyme-1 is thought to be a major factor in regulating cellular polyamine content, acting both to inhibit ornithine decarboxylase (ODC) activity and to target it for degradation, as well as preventing polyamine uptake. The two transgenic lines had substantial, but different, levels of antizyme in the heart, as detected by Western blotting and by the ability of heart extracts to inhibit exogenous purified ODC. Despite the high levels of antizyme, endogenous ODC activity was not completely abolished, with 10– 39% remaining, depending on the transgenic line. Additionally, a relatively small decrease (30–32%) in cardiac spermidine content was observed, with levels of putrescine and spermine unaffected. Interestingly, although the two lines of transgenic mice had different antizyme expression levels, they had almost identical cardiac polyamine content. When treated with a single acute dose of isoprenaline (isoproterenol), cardiac ODC activity and putrescine content were substantially increased (by 14-fold and 4.7-fold respectively) in non-transgenic littermate mice, but these increases were completely prevented in the transgenic mice from both founder lines. Prolonged exposure to isoprenaline also caused increases in cardiac ODC activity and polyamine content, as well as an increase in cardiac growth, in non-transgenic mice. Although the increases in cardiac ODC activity and polyamine content were prevented in the transgenic mice from both founder lines, the increase in cardiac growth was unaffected. These transgenic mice thus provide a valuable model system in which to study the importance of polyamine levels in cardiac growth and electrophysiology in response to stress.

Unusual aspects of the polyamine transport system affect the design of strategies for use of polyamine analogues in chemotherapy

2007 ◽  
Vol 35 (2) ◽  
pp. 318-321 ◽  
Author(s):  
J.L.A. Mitchell ◽  
T.K. Thane ◽  
J.M. Sequeira ◽  
R. Thokala
Keyword(s):  
Regulatory Protein ◽  
Feedback System ◽  
Uptake System ◽  
Polyamine Synthesis ◽  
Polyamine Analogues ◽  
Binding Partners ◽  
Polyamine Transport ◽  
Polyamine Uptake ◽  
Tumour Cell Growth

One strategy for inhibiting tumour cell growth is the use of polyamine mimetics to depress endogenous polyamine levels and, ideally, obstruct critical polyamine-requiring reactions. Such polyamine analogues make very unusual drugs, in that extremely high intracellular concentrations are required for growth inhibition or cytotoxicity. Cells exposed to even sub-micromolar concentrations of such analogues can achieve effective intracellular levels because these compounds are incorporated by the very aggressive polyamine uptake system. Once incorporated to these levels, many of these analogues induce the synthesis of a regulatory protein, antizyme, which inhibits both polyamine synthesis and the transporter they used to enter the cell. Thus this feedback system allows steady-state maintenance of effective cellular doses of such analogues. Accordingly, effective cellular levels of polyamine analogues are generally inversely related to their capacity to induce antizyme. Antizyme activity is down-regulated by interaction with several binding partners, most notably antizyme inhibitor, and at least a few tumour tissues exhibit deficiencies in antizyme expression. Our studies explore the role of antizyme induction by several polyamine analogues in their physiological response and the possibility that cell-to-cell differences in antizyme expression may contribute to variable sensitivities to these agents.

scholarly journals GSTΠ stimulates caveolin-1-regulated polyamine uptake via actin remodeling

Oncotarget ◽  
2019 ◽  
Vol 10 (55) ◽  
pp. 5713-5723 ◽  
Author(s):  
Takeshi Uemura ◽  
George Tsaprailis ◽  
Eugene W. Gerner
Keyword(s):  
Actin Remodeling ◽  
Caveolin 1 ◽  
Polyamine Uptake

Calcium/Calmodulin Affects Microtubule Stability in Lysed Protoplasts

1991 ◽  
Vol 100 (2) ◽  
pp. 311-317
Author(s):  
RICHARD J. CYR
Keyword(s):  
Cell Cycle ◽  
Dynamic Behavior ◽  
Growth And Development ◽  
Higher Plants ◽  
Plant Cells ◽  
Microtubule Stability ◽  
A Cell ◽  
Cycle Dependent ◽  
Carrot Protoplasts

Microtubules (Mts) are found in four distinct arrays appearing sequentially in a cell-cycle-dependent fashion within the cells of higher plants. Additionally, the cortical Mts of non-cycling cells are spatially altered in a variety of differentiated states. Information regarding the molecular details underlying these Mt-reorientation events in plant cells is scarce. Moreover, it is unclear how cytoskeletal behavior integrates with the myriad of other cellular activities that are altered concomitantly in both differentiating and cycling cells. Data are presented herein to indicate that calcium, in the form of a Ca2+/calmodulin complex, can alter the behavior of Mts in lysed carrot protoplasts. Mechanistically, we show that Ca2+/calmodulin most likely interacts with Mts via associations with microtubule associated pro- teins (MAPS). These results are discussed with reference to how Ca2+ may alter the dynamic behavior of Mts during growth and development.

scholarly journals The involvement of polyamine uptake and synthesis pathways in the proliferation of neonatal astrocytes

Amino Acids ◽  
2020 ◽  
Vol 52 (8) ◽  
pp. 1169-1180
Author(s):  
Christian J. Malpica-Nieves ◽  
David E. Rivera-Aponte ◽  
Flavia A. Tejeda-Bayron ◽  
Angel M. Mayor ◽  
Otto Phanstiel ◽  
...  
Keyword(s):  
Polyamine Uptake

scholarly journals polyamine uptake transporter 2 (put2) and decaying seeds enhance phyA-mediated germination by overcoming PIF1 repression of germination

PLoS Genetics ◽  
2019 ◽  
Vol 15 (7) ◽  
pp. e1008292 ◽  
Author(s):  
Woohyun Kim ◽  
Sanja Ćavar Zeljković ◽  
Urszula Piskurewicz ◽  
Christian Megies ◽  
Petr Tarkowski ◽  
...  
Keyword(s):  
Polyamine Uptake

scholarly journals Transport systems for polyamines in the established renal cell line LLC-PK1. Polarized expression of an Na+-dependent transporter

1990 ◽  
Vol 265 (2) ◽  
pp. 609-612 ◽  
Author(s):  
L Van Den Bosch ◽  
H De Smedt ◽  
L Missiaen ◽  
J B Parys ◽  
R Borghgraef
Keyword(s):  
Cell Line ◽  
Renal Cell ◽  
The Other ◽  
Transport Systems ◽  
Present Evidence ◽  
Cell Monolayers ◽  
Other Hand ◽  
Basolateral Side ◽  
Renal Cell Line ◽  
Polyamine Uptake

We present evidence for the existence of an Na(+)-dependent transporter and an Na(+)-independent transporter for polyamines in LLC-PK1 cells. Both transporters could be discriminated by their sensitivity to inhibitors, particularly rho-chloromercuriphenyl sulphate and various polycationic molecules. By using cell monolayers grown on a permeable filter support, we have found that the Na(+)-dependent polyamine uptake occurred preferentially from the basolateral side. The Na(+)-independent uptake, on the other hand, occurred to the same extent from either the apical or the basolateral side.

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