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1.
Involvement of nitric oxide-induced NADPH oxidase in adventitious root growth and antioxidant defense in Panax ginseng 总被引:1,自引:0,他引:1
Rajesh Kumar Tewari Soohyun Kim Eun-Joo Hahn Kee-Yoeup Paek 《Plant biotechnology reports》2008,2(2):113-122
Nitric oxide (NO) affects the growth and development of plants and also affects plant responses to various stresses. Because
NO induces root differentiation, we examined whether or not it is involved in increased ROS generation. Treatments with sodium
nitroprusside (SNP), an NO donor, 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO), a specific NO scavenger,
and Nω-nitro-l-arginine methyl ester hydrochloride (l-NAME), an NO synthase (NOS) inhibitor, revealed that NO is involved in the adventitious root growth of mountain ginseng.
Supply of an NO donor, SNP, activates NADPH oxidase activity, resulting in increased generation of O2
·−, which subsequently induces growth of adventitious roots. Moreover, treatment with diphenyliodonium chloride (DPI), an NADPH
oxidase inhibitor, individually or with SNP, inhibited root growth, NADPH oxidase activity, and O2
·− anion generation. Supply of the NO donor, SNP, did not induce any notable isoforms of enzymes; it did, however, increase
the activity of pre-existing bands of NADPH oxidase, superoxide dismutase, catalase, peroxidase, ascorbate peroxidase, and
glutathione reductase. Enhanced activity of antioxidant enzymes induced by SNP supply seems to be responsible for a low level
of H2O2 in the adventitious roots of mountain ginseng. It was therefore concluded that NO-induced generation of O2
·− by NADPH oxidase seems to have a role in adventitious root growth of mountain ginseng. The possible mechanism of NO involvement
in O2
·− generation through NADPH oxidase and subsequent root growth is discussed. 相似文献
2.
Nitric oxide (NO) is a highly reactive, membrane-permeable free radical, which has recently emerged as an important signalling
molecule and antioxidant. Here we investigated the protective effect of NO against the toxicity caused by excess CuSO4 (50 μM) in the adventitious roots of mountain ginseng. It was found that NO donor, sodium nitroprusside (SNP), was effective
in reducing Cu-induced toxicity in the mountain ginseng adventitious roots. Protective effect of SNP, as indicated by extent
of lipid peroxidation, was reversed by incorporation of 2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide
(CPTIO), a NO scavenger, in the medium suggesting that the protective effect of SNP is attributable to NO released, which
was revealed from in situ confocal laser scanning microscopic localization of NO in the adventitious roots of mountain ginseng.
Results obtained in the present study suggest that reduction of excess Cu-induced toxicity by SNP is most likely mediated
through the modulation in the activities of antioxidant enzymes involved in H2O2 detoxification (catalase, peroxidase, ascorbate peroxidase) and in the maintenance of cellular redox couples (glutathione
reductase), and contents of molecular antioxidants (particularly non-protein thiol, ascorbate and its redox status). Exogenous
NO supply also improved the activity of superoxide dismutase, an enzyme responsible for O2
·− dismutation, and NADPH oxidase, an enzyme responsible for O2
·− generation, in excess Cu supplied adventitious roots of mountain ginseng. 相似文献
3.
Suk Young Oh Chun Hua Wu Elena Popova Eun Joo Hahn Kee Yoeup Paek 《Journal of Plant Biology》2009,52(4):348-354
We tested desiccation and/or vitrification procedures to cryopreserve the adventitious roots of Panax ginseng, the source of commercially produced ginsenosides. When only desiccation was applied, the post-freeze survival of 3- to 4-mm
root tips was <14% regardless of the composition of the preculture medium or the explant origin. Callus formation was frequently
observed after cryopreservation. In contrast, 90% survival and 32.5% root formation efficiency were achieved after cryopreservation
when a vitrification protocol was followed. Adventitious root cultures in flasks and bioreactors were reestablished from root
tips cryopreserved by vitrification. A prolonged lag-phase and lower biomass production were recorded in post-freeze-regenerated
cultures compared with control roots that were subcultured four times in flasks. However, biomass accumulations did not differ
between control and regenerated roots at the end of the sixth subculturing period. After 40 days of culture in bioreactors,
a mean value of 12.5 g dw L−1 was recorded for post-freeze-regenerated cultures versus 9.1 g dw L−1 for the control roots. Production of triol and diol ginsenosides in our bioreactor cultures also was enhanced after cryopreservation,
by 41.0% and 89.8%, respectively. These results suggest that the vitrification method is successful for cryopreservation of
P. ginseng adventitious roots. 相似文献
4.
Konstantin V. Kiselev Anna V. Turlenko Galina K. Tchernoded Yuri N. Zhuravlev 《Plant cell reports》2009,28(8):1273-1278
It has been shown previously that the rolC gene from Agrobacterium tumefaciens gene was stably and highly expressed in 15-year-old Panax ginseng transgenic cell cultures. In the present report, we analyze in detail the nucleotide composition of the rolC and nptII (neomycin phosphotransferase) genes, which is the selective marker used for transgenic cell cultures of P.
ginseng. It has been established that the nucleotide sequences of the rolC and nptII genes underwent mutagenesis during cultivation. Particularly, 1–4 nucleotide substitutions were found per sequence in the
540 and 798 bp segments of the complete rolC and nptII genes, respectively. Approximately half of these nucleotide substitutions caused changes in the structure of the predicted
gene product. In addition, we attempted to determine the rate of accumulation of these changes by comparison of DNA extracted
from P.
ginseng cell cultures from 1995 to 2007. It was observed that the frequency of nucleotide substitutions for the rolC and nptII genes in 1995 was 1.21 ± 0.02 per 1,000 nucleotides analyzed, while in 2007, the nucleotide substitutions significantly increased
(1.37 ± 0.07 per 1,000 nucleotides analyzed). Analyzing the nucleotide substitutions, we found that substitution to G or to
C nucleotides significantly increased (in 1.9 times) in the rolC and nptII genes compared with P.
ginseng
actin gene. Finally, the level of nucleotide substitutions in the rolC gene was 1.1-fold higher when compared with the nptII gene. Thus, for the first time, we have experimentally demonstrated the level of nucleotide substitutions in transferred
genes in transgenic plant cell cultures. 相似文献
5.
Two oligosaccharides, a heptasaccharide (HS) and an octasaccharide (OS), isolated from Paris polyphylla var. yunnanensis, stimulated the growth and saponin accumulation of Panax ginseng hairy roots at 5–30 mg l−1. HS and OS at 30 mg l−1, fed separately to hairy root cultures at 10 days post-inoculation, increased the root biomass dry weight by more than 70%
to ∼20 g l−1 from 13 g l−1 and the total saponin content of roots by more than 1-fold to ∼3.5% from 1.6% (w/w). The results suggest that the two oligosaccharides
may have plant growth-regulatory activity in plant tissue cultures. 相似文献
6.
Polyethylene glycol and abscisic acid improve maturation and regeneration of<Emphasis Type="Italic"> Panax ginseng</Emphasis> somatic embryos 总被引:2,自引:0,他引:2
Embryogenic culture was initiated from mature zygotic embryos of Panax ginseng. Multiple somatic embryos formed and proliferated on Murashige and Skoog medium supplemented with 2,4-dichlorophenoxyacetic acid (2.26 M) and kinetin (0.046 M). Mature as well as immature somatic embryos grew into plantlets lacking roots on the same media. Histomorphological analysis of somatic embryos treated with abscisic acid (ABA) and polyethylene glycol (PEG 4000) showed a slight improvement in the root meristem organization of torpedo-stage embryos (embryos were more compact and their cells exhibited a lower degree of vacuolation). Shoot regeneration of non-treated somatic embryos was 31% while that for somatic embryos treated with PEG 4000 and ABA was 70%. Moreover, 75% of plants regenerated from PEG- and ABA-treated embryos formed roots while plants from non-treated embryos did not form roots.Abbreviations
ABA
(±)-Abscisic acid
-
BAP
N
6-Benzyladenine
-
2,4-D
2,4-Dichlorophenoxyacetic acid
-
GA
3
Gibberellic acid
-
Kin
Kinetin
-
MS
Murashige and Skoog medium
-
PEG 4000
Polyethylene glycol 4000
-
PGR
Plant growth regulators
Communicated by H. van Onckelen 相似文献
7.
8.
9.
Propagation by softwood canes and cuttings is preferred as a practical system for vegetative reproduction of many ornamental
plant species, despite the advances in tissue culture techniques. Dracaena purplecompacta L. is a species that has a high demand for exports. Conversely, coconut water (CW) is a rich supplement that naturally contains
plant growth regulators such as indole acetic acid (IAA). The objective of this work was to evaluate the potential of CW extracts
containing natural IAA, on adventitious root development in vegetative propagation of ornamental plant canes of D. purplecompacta L. Five different concentrations (28, 57, 143, 286, 571 μM of natural IAA) of CW extracts were tested. Another set of treatment
was carried out with the same concentrations of authentic IAA hormone for comparison purpose. The 143-μM IAA CW extract recorded
the best root induction and development. It was found that the root expression was faster (5 weeks) with the use of the novel
method. In the conventional method, the canes are propagated by quick dip application of commercial product containing artificial
hormone IAA and placing them on coir fiber dust beds. It takes up to 6 weeks for the canes to develop adventitious roots to
the desired level. Steeping canes in 143-μM IAA CW extract improved rooting in D. purplecompacta L., and it was comparable to the application of 143-μM authentic IAA. The study indicates that adventitious root development,
shoot development, and leaf emergence of D. purplecompacta L. is promoted by IAA CW extracts. 相似文献
10.
Water movement across cellular membranes is regulated largely by a family of water channel proteins called aquaporins (AQPs).
Since several abiotic stresses such as, drought, salinity and freezing, manifest themselves via altering water status of plant
cells and are linked by the fact that they all result in cellular dehydration, we overexpressed an AQP (tonoplast intrinsic
protein) from Panax ginseng, PgTIP1, in transgenic Arabidopsis
thaliana plants to test its role in plant’s response to drought, salinity and cold acclimation (induced freezing tolerance). Under
favorable conditions, PgTIP1 overexpression significantly increased plant growth as determined by the biomass production, and leaf and root morphology.
PgTIP1 overexpression had beneficial effect on salt-stress tolerance as indicated by superior growth status and seed germination
of transgenic plants under salt stress; shoots of salt-stressed transgenic plants also accumulated greater amounts of Na+ compared to wild-type plants. Whereas PgTIP1 overexpression diminished the water-deficit tolerance of plants grown in shallow (10 cm deep) pots, the transgenic plants
were significantly more tolerant to water stress when grown in 45 cm deep pots. The rationale for this contrasting response,
apparently, comes from the differences in the root morphology and leaf water channel activity (speed of dehydration/rehydration)
between the transgenic and wild-type plants. Plants overexpressed with PgTIP1 exhibited lower (relative to wild-type control) cold acclimation ability; however, this response was independent of cold-regulated
gene expression. Our results demonstrate a significant function of PgTIP1 in growth and development of plant cells, and suggest that the water movement across tonoplast (via AQP) represents a rate-limiting
factor for plant vigor under favorable growth conditions and also significantly affect responses of plant to drought, salt
and cold stresses. 相似文献
11.
Kyung-Ho Ma Anupam Dixit Young-Chang Kim Dong-Yun Lee Tae-San Kim Eun-Gi Cho Yong-Jin Park 《Conservation Genetics》2007,8(6):1507-1509
Panax ginseng C.A. Meyer, commonly known as Korean or Asian ginseng, is a perennial herb native to Korea and China. Its roots are highly
prized for several medicinal properties. The present study describes development and characterization of twenty-two polymorphic
microsatellite markers for this species. A total of 99 alleles were detected with an average of 4.5 alleles per locus across
20 accessions. Values for observed (H
O
) and expected (H
E
) heterozygosities ranged from 0.05 to 1.00 and from 0.18 to 0.73, respectively. Eleven loci deviated from Hardy–Weinberg
equilibrium (P < 0.001). Significant (P < 0.05) heterozygote deficiency was observed at 13 loci. Exact test for linkage disequilibrium showed significant values
(P < 0.05) between 12 pairs of loci. These microsatellite markers provide powerful tools for understanding population and conservation
genetics of this species and also for genetic differentiation and authentication of different Panax species being used in commercial ginseng products. 相似文献
12.
13.
The chimeras between tuber mustard (Brassica juncea) and red cabbage (B. oleracea) were artificially synthesized in our previous study. Adventitious shoots were induced from nodal segments and leaf discs
of TCC (LI-LII-LIII, LI -the outmost layer of shoot apical meristem; LII -the middle layer; LIII -the innermost layer. T = Tuber
mustard, C = Red cabbage) chimeras. The origin of the shoots was analyzed by histology and molecular biology. As a result,
the frequency of adventitious shoot induction rose with the increase of BA in MS medium in the area of the nodes. However,
there was no different induction frequency of adventitious shoots from nodal segment bases in media with different BA concentrations.
Most adventitious shoots (clustered shoots) arising from the node area were TTT (Tuber mustard- Tuber mustard- Tuber mustard)
and only 4 shoots were chimeras, which indicated that more shoots originated from LI than from LII and LIII. All shoots from
nodal segment bases were CCC (Red cabbage-Red cabbage- Red cabbage), indicating that the shoots originated from LII or LII
and LIII. There were significant differences in the regeneration rate in the margin of the leaf discs among the three combinations
of BA and NAA. Most adventitious shoots from the margin of leaf discs were CCC but 2 out of 70 were chimeras, which indicated
that more shoots originated from LII or LII and LIII than from LI. All chimeras obtained by regeneration were different from
the original explant donor in type in the present study. The origin of the adventitious shoots varied with the site of origin
on the donor plant, and could be multicellular and multihistogenic. 相似文献
14.
Rajesh Kumar Tewari Soo Yeon Lee Eun Joo Hahn Kee Yoeup Paek 《Plant biotechnology reports》2007,1(4):227-235
Nitric oxide (NO) is a diffusible, gaseous signaling molecule. In plants, NO influences growth and development, and it can
also affect plant responses to various stresses. Because NO induces root differentiation and interacts with reactive oxygen
species, we examined the temporal effect of NO elicitation on root growth, saponin accumulation and antioxidant defense responses
in the adventitious roots of mountain ginseng (Panax ginseng). The observations revealed that NO is involved in root growth and saponin production. Elicitation with sodium nitroprusside
(SNP) activated O2
−-generating NADPH oxidase (NOX) activity, which most probably subsequently enhanced growth of adventitious roots of mountain
ginseng. A severe inhibition of NOX activity and decline in dry weight of SNP elicited adventitious roots in the presence
of NOX inhibitor (diphenyl iodonium, DPI), which further supports involvement of NOX in root growth. Enhanced activities of
antioxidant enzymes by SNP appear to be responsible for low H2O2, less lipid peroxidation, and modulation of ascorbate and non-protein thiol statuses in the adventitious roots of mountain
ginseng. Dry mass, saponin content and NOX activity was related with NO content present in adventitious roots of mountain
ginseng. 相似文献
15.
Distribution of small roots (diameter between 2 mm and 5 mm) was studied in 19 pits with a total of 72 m2 trench profile walls in pure stands of Fagus sylvatica and Picea abies. Root positions within the walls were marked and transformed into x-coordinates and y-coordinates. In a GIS-based evaluation, zones of potential influence around each root were calculated. The total potential
influence produced isoline maps of relative root influence zones, thus indicating small root clustering. The questions studied
were (1) whether there were marked clusters of small roots in the soil and (2) whether trees surrounding the pit (defined
as tree density) correlate with the root abundance and distribution on the trench profile walls. Small roots of both species
showed maximum abundance in the top 20 cm of the soil, where pronounced root clusters occurred next to areas with only low
root accumulation. The area of root clusters did not differ significantly between the two stands. Weighted clumping, WC, calculated
as a product of root class, and its area was used as an index of root clustering, which again did not differ between beech
and spruce stands. However, evaluations on a single root level showed that beech achieved the same degree of clustering with
lower number of roots. Regardless of soil properties related to root clusters, a significantly higher clustering acquired
per root for beech than for spruce suggests beech to be more efficient in belowground acquisition of space. Because none of
the parameters describing root clustering were correlated with tree density around the investigated soil profiles, clusters
of small roots are inherently present within the tree stands. 相似文献
16.
We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan. 相似文献
17.
Filipendula ulmaria (L.) Maxim (meadowsweet) is a medicinal plant that is claimed to have several biological activities, including anti-tumor,
anti-carcinogenic, anti-oxidant, anti-coagulant, anti-ulcerogenic, anti-microbial, anti-arthritic, and immunomodulatory properties.
This report describes, for the first time, an efficient plant regeneration system for F. ulmaria via adventitious shoot development from leaf, petiole, and root explants cultured on Murashige and Skoog’s minimal organics
medium containing different concentrations of thidiazuron (TDZ), benzyladenine, and kinetin either alone or in combination
with different auxins. Relatively extensive/prolific shoot regeneration was observed in all three explant types with TDZ in
combination with indole-3-acetic acid (IAA). Gibberellic acid (GA3), TDZ, and IAA combinations were also tested. The best shoot proliferation was observed among root explants cultured on media
supplemented with 0.45 μM TDZ + 2.85 μM IAA + 1.44 μM GA3. Regenerated shoots were transferred to rooting media containing different concentrations of either IAA, indole-3-butyric
acid (IBA), naphthalene acetic acid, or 2,4-dichlorophenoxyacetic acid. Most shoots developed roots on medium with 2.46 μM
IBA. Rooted explants were transferred to vermiculite in Magenta containers for a 2-wk acclimatization period and then finally
to plastic pots containing potting soil. The plantlets in soil were kept in growth chambers for 2 wk before transferring to
greenhouse conditions. 相似文献
18.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae. 相似文献
19.
Innocenti G Pucciariello C Le Gleuher M Hopkins J de Stefano M Delledonne M Puppo A Baudouin E Frendo P 《Planta》2007,225(6):1597-1602
Glutathione (GSH) is one of the main antioxidants in plants. Legumes have the specificity to produce a GSH homolog, homoglutathione
(hGSH). We have investigated the regulation of GSH and hGSH synthesis by nitric oxide (NO) in Medicago truncatula roots. Analysis of the expression level of gamma-glutamylcysteine synthetase (γ-ECS), glutathione synthetase (GSHS) and homoglutathione
synthetase (hGSHS) after treatment with sodium nitroprusside (SNP) and nitrosoglutathione (GSNO), two NO-donors, showed that
γ-ecs and gshs genes are up regulated by NO treatment whereas hgshs expression is not. Differential accumulation of GSH was correlated to gene expression in SNP-treated roots. Our results provide
the first evidence that GSH synthesis pathway is regulated by NO in plants and that there is a differential regulation between
gshs and hgshs in M. truncatula.
G. Innocenti and C. Pucciariello have contributed equally to the work. 相似文献