共查询到20条相似文献,搜索用时 31 毫秒
1.
The effects of a number of different elicitors on asiaticoside production in whole plant cultures of Centella asiatica were studied, including yeast extract, CdCl2, CuCl2 and methyl jasmonate (MJ). Only MJ and yeast extract stimulated asiaticoside production—1.53 and 1.41-fold, respectively. Maximum asiaticoside production was achieved following treatment with 0.1 mM MJ (116.8 mg/l). The highest asiaticoside production (342.72 mg/l) was obtained after 36 days of elicitation in cultures treated with 0.1 mM MJ and 0.025 mg/l 1-phenyl-3-(1,2,3-thidiazol-5-yl)urea (TDZ). Interestingly, MJ not only stimulated the production of asiaticoside but also had an important role in the senescence of C. asiatica. Although asiaticoside content did not change when TDZ was added to medium containing an elicitor, TDZ did increase shoot growth of C. asiatica. We discuss the interactive roles of MJ and TDZ in secondary metabolic production and biomass in whole plants of C. asiatica 相似文献
2.
3.
We have cloned and characterized a gene for squalene synthase (SQS) fromCentella asiatica (L) Urban, a species that produces a large quantity of triterpene saponins such as asiaticoside and madecassoside. Its full-length
cDNA clone was isolated by RACE PCR. The sequence ofpSQS contains an open reading frame of 1248 nucleotides, which code for 416 amino acids with a molecular mass of 47.3 kDa. Southern
analysis revealed that one copy might exist in the C.asiatica genome. We also determined that 0.1 mM methyl jasmonate was sufficient to up-regulate those levels ofCaSQS mRNA. 相似文献
4.
Summary Cysteme synthase, the key enzyme for fixation of inorganic sulfide, catalyses the formation of cysteine from O-acetylserine and inorganic sulfide. Here we report the cloning of cDNAs encoding cysteine synthase isoforms fromArabidopsis thaliana. The isolated cDNA clones encode for a mitochondrial and a plastidic isoform of cysteine synthase (O-acetylserine (thiol)-lyase, EC 4.2.99.8), designated cysteine synthase C (AtCS-C, CSase C) and B (AtCS-B; CSase B), respectively.AtCS-C andAtCS-B, having lengths of 1569-bp and 1421-bp, respectively, encode polypeptides of 430 amino acids (45.8 kD) and of 392 amino acids ( 41.8 kD), respectively. The deduced amino acid sequences of the mitochondrial and plastidic isoforms exhibit high homology even with respect to the presequences. The predicted presequence of AtCS-C has a N-terminal extension of 33 amino acids when compared to the plastidic isoform. Northern blot analysis showed thatAtCS-C is higher expressed in roots than in leaves whereas the expression ofAtCS-B is stronger in leaves. Furthermore, gene expression of both genes was enhanced by sulfur limitation which in turn led to an increase in enzyme activity in crude extracts of plants. Expression of theAtCS-B gene is regulated by light. The mitochondrial, plastidic and cytosolic (Hesse and Altmann, 1995) isoforms of cysteine synthase ofArabidopsis are able to complement a cysteine synthasedeficient mutant ofEscherichia coli unable to grow on minimal medium without cysteine, indicating synthesis of functional plant proteins in the bacterium. Two lines of evidence proved thatAtCS-C encodes a mitochondrial form of cysteine synthase; first, import ofin vitro translation products derived from AtCS-C in isolated intact mitochondria and second, Western blot analysis of mitochondria isolated from transgenic tobacco plants expressing AtCS-C cDNA/c-myc DNA fusion protein.Abbreviations CSase
cysteine synthase
The nucleotide sequence data reported will appear in the EMBL Database under the accession numbers X81973 forAtCS-C and X81698 forAtCS-B. 相似文献
5.
6.
Nam Hee Yoo Ok Tae Kim Jung Bong Kim Sun Hee Kim Young Chang Kim Kyong Hwan Bang Dong Yun Hyun Seon Woo Cha Min Young Kim Baik Hwang 《Plant biotechnology reports》2011,5(3):283-287
In order to produce centellosides from whole plant cultures of Centella asiatica (L.) Urban, we evaluated the synergistic effects of thidiazuron (TDZ) and methyl jasmonate (MJ) on whole plant growth and
centelloside production. After 4 weeks of treatment with 0.025 mg/L of TDZ coupled with 0.1 mM MJ, the production of madecassoside
and asiaticoside from whole plant cultures was estimated to be 2.40- and 2.44-fold, respectively, above that of MJ elicitation
alone. When whole plants were treated with a growth regulator and an elicitor, the growth of whole plants, as compared to
the controls, did not differ. Additionally, total phytosyterol content in the leaves of whole plants co-treated with MJ and
TDZ was 1.08-fold greater than those of MJ alone. These results demonstrate that combined treatments not only stimulate the
accumulation of centellosides in the leaves but also inhibit the reduction of phytosterol levels caused by MJ elicitation. 相似文献
7.
8.
T. Motoyama M. Fujiwara N. Kojima H. Horiuchi A. Ohta M. Takagi 《Molecular & general genetics : MGG》1996,251(4):442-450
We previously isolated three chitin synthase genes (chsA, chsB, andchsC) fromAspergillus nidulans. In the present work, we describe the isolation and characterization of another chitin synthase gene, namedchsD, fromA. nidulans. Its deduced amino acid sequence shows 56.7% and 55.9% amino acid identity, respectively, with Cal1 ofSaccharomyces cerevisiae and Chs3 ofCandida albicans. Disruption ofchsD caused no defect in cell growth or morphology during the asexual cycle and caused no decrease in chitin content in hyphae. However, double disruption ofchsA andchsD caused a remarkable decrease in the efficiency of conidia formation, while double disruption ofchsC andchsD caused no defect. Thus it appears thatchsA andchsD serve redundant functions in conidia formation. 相似文献
9.
Chlorophyll b is a photosynthetic antenna pigment found in prochlorophytes and chlorophytes. In chlorophytes, its biosynthesis regulates the photosynthetic antenna size. Chlorophyll b is synthesized from chlorophyll a in a two-step oxygenation reaction by chlorophyllide a oxygenase (CAO). In this study, we first identified the entire sequence of a prochlorophyte CAO gene from Prochlorothrix hollandica to compare it with those from chlorophytes, and we examined the catalytic activity of the gene product. Southern blot analysis showed that the CAO gene is presented in one copy in the P. hollandica genome. The P. hollandica CAO gene (PhCAO) has a coding capacity for 367 amino acids, which is much smaller than that of Arabidopsis thaliana (537 amino acids) and Oryza sativa (542 amino acids) CAO genes. In spite of the small size, PhCAO catalyzed the formation of chlorophyll b. By comparing these sequences, we classified the land-plant sequences into four parts: the N-terminal sequence predicted to be a transit peptide, the successive conserved sequence unique in land plants (A-domain, 134 amino acids), a less-conserved sequence (B-domain, 30 amino acids) and the C-terminal conserved sequence common in chlorophytes and prochlorophytes (C-domain, 337 to 344 amino acids). We demonstrated that the C-domain is sufficient for catalytic activity by transforming the cyanobacterium Synechocystis sp. PCC6803 with the C-domain from A. thaliana. In this paper, the role of the A-domain is discussed in relation to the formation of light-harvesting chlorophyll a/b–protein complexes in land plants.Abbreviations
CAO
Chlorophyllide a oxygenase
-
CP
Chlorophyll protein
-
HPLC
High-performance liquid chromatography
-
LHC
Light-harvesting complex
-
PCR
Polymerase chain reaction
-
PS
Photosystem 相似文献
10.
A. Sieboldianus (5-leaf aralia) is recalcitrant for micropropagation, but has very good landscaping potential. This research was conducted
with the following objectives: (1) to study effects of BA, TDZ, CPPU, 2iP, kinetin and zeatin in woody plant medium on the
performance of softwood shoot nodal explants produced by field grown 5-leaf aralia plants; (2) to investigate influences of
BA or TDZ in the forcing solution on subsequentin vitro shoot initiation of nodal explants taken from forced softwood growth. Shoot initiation of softwood nodal explants from field-grown
plants was promoted by adding BA, TDZ or CPPU to the culture medium. Kinetin, zeatin and 2iP were ineffective for micropropagation
ofA. Sieboldianus. The forced softwood growth for use as explants was “primed” by forcing dormant stems in solution containing 200 mg 8-HQC
per liter plus 2% sucrose, 44.4, 222, or 444 μM BA, or 45.4, 227, or 454 μM TDZ. BA and TDZ in the forcing solution enhanced
subsequentin vitro axillary shoot initiation of nodal explants taken from forced stems by doubling the number of shoots produced per explant
to 3.3 from 1.65 shoots per explant taken from field grown plants. This forcing solution technique also reduced the time needed
from culture initiation to potted plants to half of the time needed for the conventional micropropagation method (12 to 14
vs. 25 to 27 weeks), thus expediting the micropropagation ofA. Sieboldianus. 相似文献
11.
We investigated the effects of growth regulators on whole-plant cultures derived from nodes ofCentella asiatica. A B5 liquid medium including 0.01 mg L-1 2,4-D resulted in decreased growth and asiaticoside production. Among the cytokinins tested (TDZ, BA, zeatin, and kinetin),
TDZ was the best supplement for the promotion of asiaticoside biosynthesis. To directly estimate this effect, we measured
asiaticoside content in the leaf, the main organ for synthesis. The addition of TDZ did not affect asiaticoside accumulation.
Nevertheless, our results suggest that treatment with exogenous TDZ may enhance the production of asiaticoside in cultures
simply through an increase in biomass. 相似文献
12.
Matthew J. Hills Rachel Dann Derek Lydiate Andrew Sharpe 《Plant molecular biology》1994,25(5):917-920
A cDNA encoding an acyl-CoA-binding protein (ACBP) homologue has been cloned from a gt11 library made from mRNA isolated from developing seeds of oilseed rape (Brassica napus L.). The derived amino acid sequence reveals a protein 92 amino acids in length which is highly conserved when compared with ACBP sequences from yeast, cow, man and fruit fly. Southern blot analysis ofBrassica napus genomic DNA revealed the presence of 6 genes, 3 derived from theBrassica rapa parent and 3 fromBrassica oleracea. Northern blot analysis showed that ACBP genes are expressed strongly in developing embryo, flowers and cotyledons of seedlings and to a lesser extent in leaves and roots. 相似文献
13.
Jayanti Sen Sipra Guha-Mukherjee 《In vitro cellular & developmental biology. Plant》1998,34(4):276-280
Summary Cotyledonary nodes, excised cotyledons, and hypocotyl segments of six varieties ofVigna mungo andV. radiata have been tested for their morphogenic potential on media containing a range of hormonal combinations including benzyladenine,
kinetin, thidiazuron (TDZ), and zeatin. Multiple shoots developed on cotyledonary node explants in all varieties tested on
basal medium containing cytokinin. Presence of both the cotyledons, either full or half, resulted in a maximum number of shoots
produced. Shoot bud regeneration was achieved via meristem formation on excised cotyledons on Murashige-skoog basal medium
with B5 vitamins supplemented with TDZ. Mature plants had normal phenotypes.V. mungo var. PS1 andV. radiata var. Pusa 105 were found to be the most responsive varieties for shoot regneration. The histology ofin vitro organogenesis was studied. 相似文献
14.
A cDNA clone encodingS-adenosyl-L-methionine:trans-caffeoyl-CoA 3-O-methyl-transferase (EC 2.1.1.104; CCoAOMT) fromStellana longipes Goldie (long-stalked chick-weed) was isolated and studied. Structural analysis of both the nucleotide sequence and the predicted
amino acid sequence suggests that our cloned sequence encoded a CCoAOMT enzyme ofStellaria longipes, which shared overall structural similarity with other plant CCoAOMTs but exhibited certain distinct characteristics. Southern
blot hybridization and cloning analyses indicating a small CCoAOMT gene family in theStellana longipes genome and the absence of introns in the coding region of the cDNA-corresponding gene. Sequence variations in the coding
region were found among three genotypes from geographically isolated populations. Higher levels of CCoAOMT mRNA were detected
in stems and leaves than in roots. The cDNA-encoded protein expressed inEschendia coli was shown to utilize caffeoyl-CoA, but not caffeic acid or 5-hydroxy ferulic acid, as its substrate. 相似文献
15.
Tanavat Kaensaksiri Puangpaka Soontornchainaksaeng Noppamas Soonthornchareonnon Sompop Prathanturarug 《Plant Cell, Tissue and Organ Culture》2011,107(2):187-194
Mutational breeding was conducted using in vitro-grown shoot-tips of Centella asiatica (L.) Urban treated with colchicine (0.025–0.400% for 12–36 h) to induce polyploidy. Treated shoot-tips were grown on Murashige
and Skoog (MS) medium supplemented with 4.54 μM thidiazuron (TDZ), and regenerated plantlets were acclimatized and transferred
to soil. Two months following transfer to ex vitro conditions, ploidy levels of regenerated plants were determined by flow
cytometry and by determining chromosome counts. Treating shoot-tips with colchicine concentrations ranging from 0.050–0.200%
for 12–24 h promoted induction of tetraploids. Morphological and growth characteristics and the triterpenoid contents of the
polyploids were also measured. Tetraploid plants demonstrated significantly longer stomata and a higher stomatal index compared
to those of the diploid control plants. Furthermore, a positive trend in both biomass and triterpenoid production was obtained
with the tetraploid and mixoploid plants of C. asiatica. 相似文献
16.
17.
18.
Barbara Kroczynska Rengang Zhou Clifford Wood Jan A. Miernyk 《Plant molecular biology》1996,31(3):619-629
The nucleotide sequence of a cDNA clone fromArabidopsis thaliana ecotype Columbia was determined, and the corresponding amino sequence deduced. The open reading frame encodes a protein, AtJ1, of 368 residues with a molecular mass of 41 471 Da and an isoelectric point of 9.2. The predicted sequence contains regions homologous to the J- and cysteine-rich domains ofEscherichia coli DnaJ, but the glycine/phenylalanine-rich region is not present. Based upon Southern analysis,Arabidopsis appears to have a singleatJ1 structural gene. A single species of mRNA, of 1.5 kb, was detected whenArabidopsis poly(A)+ RNA was hybridized with theatJ1 cDNA. The function ofatJ1 was tested by complementation of adnaJ deletion mutant ofE. coli, allowing growth in minimal medium at 44°C. The AtJ1 protein was expressed inE. coli as a fusion with the maltose binding protein. This fusion protein was purified by amylose affinity chromatography, then cleaved by digestion with the activated factor X protease. The recombinant AtJ1 protein was purified to electrophoretic homogeneity.In vitro, recombinant AtJ1 stimulated the ATPase activity of bothE. coli DnaK and maize endosperm cytoplasmic Stress70. The deduced amino acid sequence of AtJ1 contains a potential mitochondrial targeting sequence at the N-terminus. Radioactive recombinant AtJ1 was synthesized inE. coli and purified. When the labeled protein was incubated with intact pea cotyledon mitochondria, it was imported and proteolytically processed in a reaction that depended upon an energized mitochondrial membrane.Abbreviations MBP
maltose binding protein
- PCR
polymerase chain reaction
- Stress70c
the cytosolic member of the 70 kDA family of stress-related proteins 相似文献
19.
Sawai S Akashi T Sakurai N Suzuki H Shibata D Ayabe S Aoki T 《Plant & cell physiology》2006,47(5):673-677
Sterols, essential eukaryotic constituents, are biosynthesized through either cyclic triterpenes, lanosterol (fungi and animals) or cycloartenol (plants). The cDNA for OSC7 of Lotus japonicus was shown to encode lanosterol synthase (LAS) by the complementation of a LAS-deficient mutant yeast and structural identification of the accumulated lanosterol. A double site-directed mutant of OSC7, in which amino acid residues crucial for the reaction specificity were changed to the cycloartenol synthase (CAS) type, produced parkeol and cycloartenol. The multiple amino acid sequence alignment of a conserved region suggests that the LAS of different eukaryotic lineages emerged from the ancestral CAS by convergent evolution. 相似文献
20.
Akihiro Kubo Hikaru Saji Kiyoshi Tanaka Kunisuke Tanaka Noriaki Kondo 《Plant molecular biology》1992,18(4):691-701
A cDNA clone encoding ascorbate peroxidase (AP, EC 1.11.1.11) was isolated from a phage gt11 library of cDNA fromArabidopsis thaliana by immunoscreening with monoclonal antibodies against the enzyme, and then sequenced. The cDNA insert hybridized to a 1.1 kb poly(A)+ RNA from leaves ofA thaliana. Genomic hybridization suggests that the cDNA obtained here corresponds to a single-copy gene. The N-terminal amino acid sequence ofArabidopsis AP was determined by protein sequencing of the immunochemically purified enzyme, and proved to be homologous to the N-terminal amino acid sequence of the chloroplastic AP of spinach. The predicted amino acid sequence of the mature AP ofA. thaliana, deduced from the nucleotide sequence, consists of 249 amino acid residues, which is 34% homologous with cytochromec peroxidase of yeast, but less homologous with other plant peroxidases. Amino acid residues at the active site of yeast cytochromec peroxidase are conserved in the amino acid sequence ofArabidopsis AP. The poly(dG-dT) sequence, which is a potential Z-DNA-forming sequence, was found in the 3 untranslated region of the cDNA. 相似文献