共查询到20条相似文献,搜索用时 15 毫秒
1.
Jiang K Pi Y Hou R Zeng H Huang Z Zhang Z Sun X Tang K 《Molecular biology reports》2009,36(3):487-493
In jasmonate biosynthetic pathway, allene oxide synthase (AOS, EC 4.2.1.92), which is a cytochrome P450 (CYP74A), catalyzes
the first committed step. We herein cloned a novel cDNA from Lonicera japonica Thunb., named LjAOS (GenBank accession: DQ303120), which was homologous to other AOSs. Southern blot analysis revealed that it was a multi-copy gene. Real-time quantitative PCR analysis showed that LjAOS mRNA accumulated most abundantly in alabastrums, in which the content of chlorogenic acid (CA, the major important active
ingredient indicator) was previously proven to be the highest. 相似文献
2.
In the endeavor to enhance the production of pharmaceutically valuable tropane alkaloids including hyoscyamine and scopolamine
in Hyoscyamus niger, methyl jasmonate (MeJA) showed significant stimulation both in tropane biosynthetic pathway enzymes activities and tropane
alkaloids yields. Therefore it was speculated that genetic engineering of jasmonate biosynthetic pathway might enhance the
endogenous jasmonates concentration, followed by stimulating the production of tropane alkaloids. Herein a full-length cDNA
encoding allene oxide synthase (AOS, EC 4.2.1.92), the first committed step enzyme in jasmonate biosynthetic pathway was reported
(named HnAOS, GenBank accession: EF532599). HnAOS was a novel member of the cytochrome P450 (CYP74A) subfamily. Real-time quantitative PCR analysis showed that HnAOS mRNA accumulated mainly in stems, and responded significantly to wounding or methyl jasmonate.
The article is published in the original. 相似文献
3.
Bin Liu Wenguo Wang Jihai Gao Fang Chen Shenghua Wang Ying Xu Lin Tang Yongjiong Jia 《Acta Physiologiae Plantarum》2010,32(3):531-539
Herein, we cloned a full-length cDNA encoding allene oxide cyclase (AOC, EC 5.3.99.6) that is a key enzyme in jasmonates (JAs)
biosynthetic pathway from Jatropha curcas L., an important plant species as its seed is the raw material for biodiesels, named as JcAOC (GenBank accession no. FJ874630). The cDNA was 924 bp in length with a complete open reading frame of 750 bp, which encoded
a polypeptide of 250 amino acids including a putative signal peptide of 65 amino acid residues and a mature protein of 185
amino acids with a predicted molecular mass of 20.7 kDa and a isoelectric point of 6.24. Phylogenetic analysis indicated that
JcAOC belonged to the AOC superfamily. Semi-quantitative RT-PCR analysis revealed that JcAOC mRNA was expressed in roots, stems, leaves, young seeds, endosperms, and flowers, but that the expression level was highest
in leaves and lowest in seeds, and mRNA expression of JcAOC could be induced by salt stress (300 mM NaCl) and low temperature (4°C). Furthermore, the full-length coding region of JcAOC excluding signal peptide sequence was inserted into pET-30a and was successfully expressed in Escherichia coli. Overexpression of JcAOC in E. coli conferred its resistance to salt stress and low temperature. 相似文献
4.
Keji Jiang Zhihua Liao Yan Pi Zhuoshi Huang Rong Hou Ying Cao Qing Wang Xiaofen Sun Kexuan Tang 《Molecular Biology》2008,42(3):381-390
Hyoscyamus niger L. is a medicinal plant which produces a class of jasmonate-responsive pharmaceutical secondary metabolites named tropane
alkaloids. As a family of signaling phytohormones, jasmonates play significant roles in the biosynthesis of many plant secondary
metabolites. In the jasmonate biosynthetic pathway of plants, allene oxide cyclase (AOC, EC 5.3.99.6) catalyzes the most important
step. Here we cloned a cDNA from H. niger, named HnAOC (GenBank accession no.: AY708383), which was 1044 bp long, with a 747-bp open reading frame (ORF) encoding a polypeptide
of 248 amino acid residues. Southern blot analysis indicated that it was a multicopy gene. RT-PCR analysis revealed that the
expression of HnAOC was regulated by various stresses and elicitors, with methyl-jasmonate showing the most prominent inducement. The characterization
of HnAOC would be helpful for improving the production of valuable secondary metabolites by regulating the biosynthesis of jasmonates.
The text was submitted by the authors in English. 相似文献
5.
Waleerat Banyai Chalermpol Kirdmanee Masahiro Mii Kanyaratt Supaibulwatana 《Plant Cell, Tissue and Organ Culture》2010,103(2):255-265
Transgenic plants of Artemisia annua L., a medicinal plant that produces the compound artemisinin which has an anti-malarial activity, were developed following
Agrobacterium tumefaciens-mediated transformation of leaf explants. A. tumefaciens strain EHA105 carrying either pCAMBIA1301 or pCAMBIAFPS was used. Both plasmids harbored the hygromycin phosphotransferase
II (hptII) gene as a selectable gene, but the latter plasmid also harbored the gene encoding for farnesyl pyrophosphate synthase
(FPS), a key enzyme for artemisinin biosynthesis. Shoot regeneration was observed either directly from leaf sections or via intervening
callus when explants were incubated on solidified Murashige and Skoog (MS) (1962) medium containing 0.1 mg l−1 α-naphthaleneacetic acid (NAA), 1 mg l−1 N6-benzyladenine (BA), 30 mg l−1 meropenem and 10 mg l−1 hygromycin. Applying vacuum infiltration dramatically increased transformation efficiency up to 7.3 and 19.7% when plasmids
with and without FPS gene were used, respectively. All putative transgenic regenerants showed positive bands of hptII gene following Southern blot analysis. Expression of FPS was observed in all transgenic lines, and FPS over-expressed lines exhibited higher artemisinin content and yield, of 2.5- and 3.6-fold, respectively, than that detected
in wild-type plants. A relatively high correlation (R
2 = 0.78) was observed between level of expression of FPS and artemisinin content. However, gene silencing was detected in some transgenic lines, especially for those lines containing
two copies of the FPS transgene, and with some lines exhibiting reduced growth. 相似文献
6.
Pu Shi Xueqing Fu Meng Liu Qian Shen Weimin Jiang Ling Li Xiaofen Sun Kexuan Tang 《Plant Cell, Tissue and Organ Culture》2017,129(2):251-259
Artemisinin, isolated from an annual herbaceous plant Artemisia annua L., is an effective antimalarial compound. However, artemisinin is accumulated in small amounts (0.01–0.1% leaf dry weight) in A. annua, resulting in constant high artemisinin price. Although metabolic engineering of partial artemisinin metabolic pathway in yeast achieved great success, artemisinin from A. annua is still the important business resource. Here, we report on the generation of transgenic plants with simultaneously overexpressing four artemisinin biosynthetic pathway genes, amorpha-4,11-diene synthase gene (ADS), amorpha-4,11-diene 12-monooxygenase gene (CYP71AV1), cytochrome P450 reductase gene (CPR), and aldehyde dehydrogenase 1 gene (ALDH1) via Agrobacterium-mediated transformation. The qRT-PCR analysis demonstrated that the introduced four genes of the transgenic lines were all highly expressed. Through high-performance liquid chromatography analysis, the artemisinin contents were increased markedly in transformants, with the highest being 3.4-fold higher compared with non-converter. These results indicate that overexpression of multiple artemisinin biosynthetic pathway genes is a promising approach to improve artemisinin yield in A. annua. 相似文献
7.
Characterization of development and artemisinin biosynthesis in self-pollinated <Emphasis Type="Italic">Artemisia annua</Emphasis> plants 总被引:1,自引:0,他引:1
Artemisia annua L. is the only natural resource that produces artemisinin (Qinghaosu), an endoperoxide sesquiterpene lactone used in the
artemisinin-combination therapy of malaria. The cross-hybridization properties of A. annua do not favor studying artemisinin biosynthesis. To overcome this problem, in this study, we report on selection of self-pollinated
A. annua plants and characterize their development and artemisinin biosynthesis. Self-pollinated F2 plants selected were grown under
optimized growth conditions, consisting of long day (16 h of light) and short day (9 h of light) exposures in a phytotron.
The life cycles of these plants were approximately 3 months long, and final heights of 30–35 cm were achieved. The leaves
on the main stems exhibited obvious morphological changes, from indented single leaves to odd, pinnately compound leaves.
Leaves and flowers formed glandular and T-shaped trichomes on their surfaces. The glandular trichome densities increased from
the bottom to the top leaves. High performance liquid chromatography–mass spectrometry-based metabolic profiling analyses
showed that leaves, flowers, and young seedlings of F2 plants produced artemisinin. In leaves, the levels of artemisinin increased
from the bottom to the top of the plants, showing a positive correlation to the density increase of glandular trichomes. RT-PCR
analysis showed that progeny of self-pollinated plants expressed the amorpha-4, 11-diene synthase (ADS) and cytochrome P450
monooxygenase 71 AV1 (CYP71AV1) genes, which are involved in artemisinin biosynthesis in leaves and flowers. The use of self-pollinated
A. annua plants will be a valuable approach to the study of artemisinin biosynthesis. 相似文献
8.
Gao-Jie Hong Wen-Li Hu Jian-Xu Li Xiao-Ya Chen Ling-Jian Wang 《Plant Molecular Biology Reporter》2009,27(3):334-341
9.
Although crosstalk between cytosolic and plastidic terpenoid pathways has been validated in many plant species, we report
here for the first time a striking elevation of the nucleus-encoded artemisinin biosynthesis relevant DBR2 mRNA following the incubation of plants with fosmidomycin (FM). FM decreased singlet oxygen (1O2) scavengers such as β-carotene and α-tocopherol and subsequently invoked 1O2 burst. The treatment of plants with fluridone (FD) neither decreased α-tocopherol content nor triggered 1O2 emission. In conclusion, FM can up-regulate 1O2-sensitive nuclear genes responsible for artemisinin biogenesis by mitigating the accumulation of plastidic scavenging terpenoids,
thereby eliciting 1O2 generation and initiating 1O2 retrograde signaling. 相似文献
10.
11.
Pajerowska-Mukhtar KM Mukhtar MS Guex N Halim VA Rosahl S Somssich IE Gebhardt C 《Planta》2008,228(2):293-306
Natural variation of plant pathogen resistance is often quantitative. This type of resistance can be genetically dissected in quantitative resistance loci (QRL). To unravel the molecular basis of QRL in potato (Solanum tuberosum), we employed the model plant Arabidopsis thaliana for functional analysis of natural variants of potato allene oxide synthase 2 (StAOS2). StAOS2 is a candidate gene for QRL on potato chromosome XI against the oömycete Phytophthora infestans causing late blight, and the bacterium Erwinia carotovora ssp. atroseptica causing stem black leg and tuber soft rot, both devastating diseases in potato cultivation. StAOS2 encodes a cytochrome P450 enzyme that is essential for biosynthesis of the defense signaling molecule jasmonic acid. Allele non-specific dsRNAi-mediated silencing of StAOS2 in potato drastically reduced jasmonic acid production and compromised quantitative late blight resistance. Five natural StAOS2 alleles were expressed in the null Arabidopsis aos mutant under control of the Arabidopsis AOS promoter and tested for differential complementation phenotypes. The aos mutant phenotypes evaluated were lack of jasmonates, male sterility and susceptibility to Erwinia carotovora ssp. carotovora. StAOS2 alleles that were associated with increased disease resistance in potato complemented all aos mutant phenotypes better than StAOS2 alleles associated with increased susceptibility. First structure models of ‘quantitative resistant’ versus ‘quantitative susceptible’ StAOS2 alleles suggested potential mechanisms for their differential activity. Our results demonstrate how a candidate gene approach in combination with using the homologous Arabidopsis mutant as functional reporter can help to dissect the molecular basis of complex traits in non model crop plants. 相似文献
12.
During the course of our research on new actinobacterial sources, a novel actinomycete strain YIM 63101T was isolated from the surface-sterilized roots of Artemisia annua L. collected from Xishuangbanna, Yunnan province, south-west China and characterized by using a polyphasic approach. The
strain formed well-differentiated aerial and substrate mycelia. Phylogenetic analysis based on 16S rRNA gene sequences showed
that strain YIM 63101T belongs to the genus Pseudonocardia, with highest similarity to “Pseudonocardia artemisiae YIM 63587T” (99.4%). Sequence similarities between strain YIM 63101T and the other Pseudonocardia species ranged from 97.0 (Pseudonocardia saturnea IMSNU 20052T) to 94.0% (Pseudonocardia compacta IMSNU 20111T). The chemotaxonomic characteristics, such as cell wall diaminopimelic acid, whole-cell sugars, fatty acid components and
the major menaquinones suggested that the organism belonged to the genus Pseudonocardia. The G + C content of the genomic DNA was 69.4 mol%. Based on comparative analysis of physiological, biochemical and chemotaxonomic
data, including low DNA–DNA hybridization results, it is proposed that strain YIM 63101T represents a novel species of the genus Pseudonocardia, named Pseudonocardia bannaensis sp. nov. The type strain is YIM 63101T (= CCTCC AA 208077 T = DSM 45300T). 相似文献
13.
Gao-Bin Pu Dong-Ming Ma Jian-Lin Chen Lan-Qing Ma Hong Wang Guo-Feng Li He-Chun Ye Ben-Ye Liu 《Plant cell reports》2009,28(7):1127-1135
This paper provides evidence that salicylic acid (SA) can activate artemisinin biosynthesis in Artemisia annua L. Exogenous application of SA to A. annua leaves was followed by a burst of reactive oxygen species (ROS) and the conversion of dihydroartemisinic acid into artemisinin.
In the 24 h after application, SA application led to a gradual increase in the expression of the 3-hydroxy-3-methylglutaryl
coenzyme A reductase (HMGR) gene and a temporary peak in the expression of the amorpha-4,11-diene synthase (ADS) gene. However, the expression of the farnesyl diphosphate synthase (FDS) gene and the cytochrome P450 monooxygenase (CYP71AV1) gene showed little change. At 96 h after SA (1.0 mM) treatment, the concentration of artemisinin, artemisinic acid and dihydroartemisinic
acid were 54, 127 and 72% higher than that of the control, respectively. Taken together, these results suggest that SA induces
artemisinin biosynthesis in at least two ways: by increasing the conversion of dihydroartemisinic acid into artemisinin caused
by the burst of ROS, and by up-regulating the expression of genes involved in artemisinin biosynthesis. 相似文献
14.
An aerobic, non-motile, catalase-positive, Gram-stain positive actinomycete designated YIM 63233T was isolated from the surface-sterilized leaves of Artemisia annua L. and characterized using a polyphasic taxonomic approach. Optimal growth occurred at 20–28°C, pH 6.0–7.0 and in the presence
of 0–3% (w/v) NaCl. 16S rRNA gene sequence-based phylogenetic analysis showed that strain YIM 63233T clustered with species of the genus Pseudonocardia, displaying ≥1.2% sequence divergence with recognized species of this genus (from 98.8 to 94.0%). Relatively low levels of
DNA–DNA relatedness were found between strain YIM 63233T and Pseudonocardia petroleophila IMSNU 22072T, which supported the classification of strain YIM 63233T within a novel species of the genus Pseudonocardia. The G + C content of genomic DNA was 72.0 mol%. Strain YIM 63233T possessed chemotaxonomic markers that were consistent with classification in the genus Pseudonocardia, i.e. the predominant fatty acids were iso-C16:0 (32.27%), C16:0 10-methyl (8.73%) and C17:1ω8c (8.30%), whilst the predominant
menaquinone was MK-8(H4). The diagnostic diamino acid of the cell-wall peptidoglycan was meso-diaminopimelic acid. The major cell wall sugars were glucose, arabinose, galactose, mannose and rhamnose. The results of
physiological and biochemical tests and DNA–DNA hybridization allowed the phenotypic and genotypic differentiation of strain
YIM 63233T from its closest phylogenetic neighbours. Therefore, the new isolate YIM 63233T represents a novel species of the genus Pseudonocardia, for which the name Pseudonocardia serianimatus sp. nov. is proposed. The type strain is YIM 63233T (=DSM 45302T = CCTCC AA 208079T). 相似文献
15.
Noel H. Holmgren 《Brittonia》2018,70(1):115-139
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations. 相似文献
16.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes. 相似文献
17.
Changlong Shu Guixin Yan Rongyan Wang Jie Zhang Shuliang Feng Dafang Huang Fuping Song 《Applied microbiology and biotechnology》2009,84(4):701-707
A new polymerase chain reaction–restriction fragment length polymorphism method for the identification of cry8-type genes from Bacillus thuringiensis has been established by designing a pair of new universal primers. By this method, a novel gene, cry8Ga1, encoding a polypeptide of 1,157 amino acids with a deduced molecular mass of 131.2 kDa was identified and cloned from B. thuringiensis HBF-18. Recombinant B. thuringiensis strain HD8G, harboring cry8Ga1, has insecticidal activity against larvae of Melolonthidae pests: Holotrichia oblita and Holotrichia parallela. This is the first report of a Cry toxin that has insecticidal activity to Melolonthidae pest H. oblita. 相似文献
18.
The foodborne pathogen Bacillus cereus can form biofilms on various food contact surfaces, leading to contamination of food products. To study the mechanisms of
biofilm formation by B. cereus, a Tn5401 library was generated from strain UW101C. Eight thousand mutants were screened in EPS, a low nutrient medium. One mutant
(M124), with a disruption in codY, developed fourfold less biofilm than the wild-type, and its defective biofilm phenotype was rescued by complementation.
Addition of 0.1% casamino acids to EPS prolonged the duration of biofilms in the wild-type but not codY mutant. When decoyinine, a GTP synthesis inhibitor, was added to EPS, biofilm formation was decreased in the wild-type but
not the mutant. The codY mutant produced three times higher protease activity than the wild-type. Zymogram and SDS-PAGE data showed that production
of the protease (∼130 kDa) was repressed by CodY. Addition of proteinase K to EPS decreased biofilm formation by the wild-type.
Using a dpp-lacZ fusion reporter system, it was shown that that the B. cereus CodY can sense amino acids and GTP levels. These data suggest that by responding to amino acids and intracellular GTP levels
CodY represses production of an unknown protease and is involved in biofilm formation. 相似文献
19.
20.
Characterization of the horse (<Emphasis Type="Italic">Equus caballus</Emphasis>)<Emphasis Type="Italic"> IGHA</Emphasis> gene 总被引:1,自引:0,他引:1
Nucleotide sequences of the immunoglobulin constant heavy chain genes of the horse have been described for IGHM, IGHG and IGHE genes, but not for IGHA. Here, we provide the nucleotide sequence of the genomic IGHA gene of the horse (Equus caballus), including its secretion region and the transmembrane exon. The equine IGHA gene shows the typical structure of a mammalian IGHA gene, with only three exons, separated by two introns of similar size. The hinge exon is located at the 5 end of the CH2 exon and encodes a hinge region of 11 amino acids, which contains five proline residues. The coding nucleotide sequence of the secreted form of the equine IGHA gene shares around 72% identity with the human IGHA1 and IGHA2 genes, as well as the bovine, ovine, porcine and canine IGHA genes, without distinct preference for any of these species. The same species also cluster together in a phylogenetic tree of the IGHA coding regions of various mammals, whereas rodent, rabbit, marsupial and monotreme IGHA genes each build a separate cluster.The nucleotide sequences reported in this paper have been assigned the EMBL/GenBank accession numbers AY247966 and AY351982 相似文献