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1

A spermine-resistant mutant of Arabidopsis thaliana displays precocious germination

100%
Mirza J. I., Rehman A.
Acta Physiologiae Plantarum
|
1998
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tom 20
|
nr 3
From an ethylmethane sulphonate-mutagenized M₂ population of Arabidopsis thaliana L. var Landsberg erecta, a mutant was isolated on the basis of its ability to germinate in the presence of a germination inhibitory concentration (0.35 mM) of spermine. The mutant produced yellowish green seeds that lacked a mucilaginous sheath, exhibited reduced dormancy and were generally viviparous under ambient conditions. Dose-response assays indicated increased resistance of the mutant to spermine but normal sensitivity to spermidine, putrescine and abscisic acid. The spermine resistance and the associated phenotype of the mutant was inherited as a single recessive nuclear mutation. Following the genetic analysis, spermine-resistant mutant has been designated as spr2. The results suggest a role for spermine in seed dormancy.
2

Effect of gibberellins, kinetin and spermine on dormancy breaking and germination of common ash [Fraxinus excelsior L.] seed

100%
Lewandowska U., Szczotka Z.
Acta Physiologiae Plantarum
|
1992
|
tom 14
|
nr 4
3

The effect of putrescine and spermine on the biochemical activity of Wolffia arrhiza [L.] Wimm. [Lemnaceae]

100%
Czerpak R., Piotrowska A., Kuklo E. S.
Polish Journal of Natural Sciences. Supplement
|
2003
|
tom 01
4
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Role of polyamines in gastroprotection induced by epidermal growth factor

84%
Brzozowski T., Drozdowicz D., Majka J., Polonczyk-Pytko J., Konturek S. J.
Journal of Physiology and Pharmacology
|
1991
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tom 42
|
nr 2
Polyamines have been shown to stimulate cellular growth and differentiation, though their role in the prevention of acute gastric lesion induced by various noxious agents has been little studied. Epidermal growth factor (EGF) exhibits gastroprotective and ulcer healing properties due to its potent mitogenic and growth promoting action. This study was designed to compare the gastroprotective effects of spermine and EGF against gastric damage induced by absolute ethanol, acidified aspirin and stress and to determine the role of endogenous polyamines in EGF-induced gast- troprotection. Spermine and EGF significantly reduced the lesions induced by all three ulcerogens. Oral administration of spermine or subcutaneous infusion of EGF in 24 h fasted rats with chronic gastric fistula resulted in similar inhibition of gastric acid and pepsin secretion. Pretreatment with difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase (ODC), a hey enzyme in the biosynthesis of polyamines, did not affect ethanol lesions, but reversed the protective effect EGF but not spermine, against ethanol. This finding indicates that polyamines mediate, at least in part, EGF-induced gastroprotection. In tests with oral administration of aminoguanidine that is known to suppress the activity of diamino-oxidase (DAO) and to inhibit the degradation of polyamines, EGF showed a markedly enhanced gastroprotective activity against ethanol damage. Since indomethacin failed to affect the gastroprotective effects of spermine and EOF and neither of these agents influenced the mucosal generation of PGE₂ in intact or injured gastric mucosa, we conclude that prostaglandins are not the major factors in spermine- and EGF-induced gastroprotection. This study demonstrates that polyamines are highly effective against gastric lesions induced by various ulcerogens and that they act as primary mediators of EGF-induced gastroprotection.
5

Catalytic activity of mutants of yeast protein kinase CK2alpha

84%
Sajnaga E., Kubinski K., Szyszka R.
Acta Biochimica Polonica
|
2008
|
tom 55
|
nr 4
767-776
Yeast CK2 is a highly conserved member of the protein kinase CGMC subfamily composed of two catalytic (α and α′) and two regulatory (β and β′) subunits. The amino-acid sequences of both catalytic subunits are only 60% homologous. Modelling of the tertiary structure of the CK2α displays additional α-helical structures not present in the CK2α′ subunit, connecting the ATP-binding loop with the catalytic and activation loops. Deletion of this part causes drastic structural and enzymatic changes of the protein (CK2α∆91–128) with characteristics similar to yeast CK2α′ (low sensitivity to salt, heparin and spermine). Additionally, the deletion causes an over 5-fold decrease of the binding affinity for ATP and ATP-competitive inhibitors (TBBt and TBBz). The structural basis for TBBt and TBBz selectivity is provided by the hydrophobic pocket adjacent to the ATP/GTP binding site, which is smaller in CK2 than in the majority of other protein kinases. The importance of hydrophobic interactions in the binding of specific inhibitors was investigated here by mutational analysis of CK2α residues whose side chains contribute to reducing the size of the hydrophobic pocket. Site-directed mutagenesis was used to replace Val67 and Ile213 by Ala. The kinetic properties of the single mutants CK2αVal67Ala and CK2αIle213Ala, and the double mutant CK2Val67Ala Ile213Ala were studied with respect to ATP, and both inhibitors TBBt and TBBz. The Km values for ATP did not change or were very close to those of the parental kinase. In contrast, all CK2α mutants analysed displayed higher Kivalues towards the inhibitors (10 to 12-fold higher with TBBt and 3 to 6-fold with TBBt) comparing to recombinant wild-type CK2α.
6
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Polyamines and cell migration

84%
McCormack S. A., Johnson L. R.
Journal of Physiology and Pharmacology
|
2001
|
tom 52
|
nr 3
7
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The effect of spermine on regulation of antioxidant defense system under salinity in Arabidopsis thaliana

67%
Yildizoglu P., Sekmen A., Kusano T., Turkan I.
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
|
2013
|
tom 94
|
nr 2
8
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Arginine metabolism during NO- and polyamines-induced dormancy removal and germination of apple embryos

67%
Budnicka K., Krasuska U., Bogatek R., Gniazdowska A.
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
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2013
|
tom 94
|
nr 3
9

Polyamines and scavenging system: influence of exogenous spermidine on catalase and guaiacol peroxidase activities, and free polyamine level in barley leaves under water deficit

67%
Kubis J.
Acta Physiologiae Plantarum
|
2003
|
tom 25
|
nr 4
10

Spermine protects in vivo the antioxidant enzymes in transiently hypoperfused rat brain

67%
Farbiszewski R., Bielawski K., Bielawska A., Sobaniec W.
Acta Neurobiologiae Experimentalis
|
1995
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tom 55
|
nr 4
11

Spermine and putrescine enhance oxidative stress tolerance in maize leaves

67%
Durmus N., Kadioglu A.
Acta Physiologiae Plantarum
|
2005
|
tom 27
|
nr 4A
The protective effects of spermine (SPM) and putrescine (PUT) against paraquat (PQ), a herbicide in agriculture and oxidative stress inducer, were investigated in the leaves of maize. Maize leaves were pretreated to SPM and PUT at concentrations of 0.2 and 1 mM and treated with PQ afterwards. Pretreatment with 1 mM of SPM and PUT significantly prevented the losses in chlo rophyll and carotenoid levels induced by PQ. Ascorbic acid content in the leaves pretreated with both polyamines was found to be higher than those of the leaves pretreated with water. Also, pretreatment with SPM and PUT was determined to have some effects on the activities of superoxide dismutase (SOD) and peroxidase (POD). 1 mM of SPM increased SOD activity, but PUT has no significant effect on SOD activity. On the other hand, POD activity was rer corded to increase slightly in response to both concentrations of SPM and 1 mM of PUT. The results showed that such polyamine pretreated plants may become more tolerant to oxidative stress due to increases in the antioxidative enzymes and antioxidants.
12

Proteins and polyamines during dormancy breaking of European beech [Fagus sylvatica L.] seeds

67%
Szczotka Z., Pawlowski T., Krawiarz K.
Acta Physiologiae Plantarum
|
2003
|
tom 25
|
nr 4
13
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Biochemical activity of di- and polyamines in the green alga Chlorella vulgaris Beijerinck [Chlorophyceae]

67%
Czerpak R., Bajguz A., Piotrowska A., Dobrogowska R., Matejczyk M., Wieslawski W.
Acta Societatis Botanicorum Poloniae
|
2003
|
tom 72
|
nr 1
This study concerns on the influence of diamines (agmatine, putrescine) and polyamines (spermine, spermidine) upon the growth and the content of chlorophyll a and b, monosaccharides and proteins in the cells of alga Chlorella vulgaris Beijerinck (Chlorophyceae). In the experiments agmatine, putrescine, spermine and spermidine in the range of concentrations 10-6-10-3 M were used. At the concentration 10-3 M and the 1st day of cultivation, they have a toxic effect on growth of the algae. It was found that di- and polyamines used within the range of concentration 10-6-10-4 M stimulate the growth and the contents of analysed biochemical parameters in the cells of C. vulgaris. The most stimulating influence on metabolism of the alga was demonstrated by spermidine and putrescine at concentration of 10-4 M. Agmatine and spermine were characterised by a lower biological activity than spermidine and putrescine demonstrated the most stimulating influence.
14

Up-regulation of spermidine-spermine N1-acetyltransferase [SSAT] expression is a part of proliferative but not anabolic response of mouse kidney

59%
Dudkowska M., Stachurska A., Grzelakowska-Sztabert B., Manteuffel-Cymborowska M.
Acta Biochimica Polonica
|
2002
|
tom 49
|
nr 4
A differential expression pattern of spermidine/spermine N1-acetyltransferase (SSAT), the enzyme critical to proper homeostasis of cellular polyamines, is reported in mouse kidney undergoing hyperplasia and hypertrophy. We have shown that SSAT activity and SSAT mRNA are significantly induced by antifolate CB 3717 and folate that evoke a drug-injury-dependent hyperplasia. In contrast, SSAT activity is down-regulated in the testosterone-induced hypertrophic kidney, while SSAT mRNA is positively controlled by this androgen. Catecholamine depletion evoked by reser- pine drastically decreases the folate-induced activity of «S-adenosylmethionine decar- boxylase (AdoMetDC), which limits polyamine biosynthesis, but has no effect on SSAT activity augmented by CB 3717. Our results document that the increased SSAT expression solely accompanies the proliferative response of mouse kidney, and sug­gest the importance of post-transcriptional regulation to the control of SSAT activity in both hyperplastic and hypertrophic experimental models.
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