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1.
Summary The generation of transgenic Cucumis sativus cv. Greenlong plants resistant to phosphinothricin (PPT) was obtained using Agrobacterium tumefaciens-mediated gene transfer. The protocol relied on the regeneration of shoots from cotyledon explants. Transformed shoots were
obtained on Murashige and Skoog medium supplemented with 4.4 μM 6-benzylaminopurine 3.8 μM abscisic acid, 108.5 μM adenine sulfate, and 2 mg l−1 phosphinothricin. Cotyledons were inoculated with the strain EHA105 harboring the neomycin phosphotransferase II (npt II), and phosphinothricin resistance (bar) genes conferring resistance to kanamycin and PPT. Transformants were selected by using increasing concentrations of PPT
(2–6 mg l−1). Elongation and rooting of putative transformants were performed on PPT-containing (2 mg l−1) medium with 1.4 μM gibberellic acid and 4.9 μM indolebutyric acid, respectively. Putative transformants were confirmed for transgene insertion through PCR and Southern
analysis. Expression of the bar gene in transformed plants was demonstrated using a leaf painting test with the herbicide Basta. Pre-culture of explants
followed by pricking, addition of 50 μM acetosyringone during infection, and selection using PPT rather than kanamycin were found to enhance transformation frequency
as evidenced by transient β-glucuronidase assay. Out of 431 co-cultivated explants, 7.2% produced shoots that rooted and grew
on PPT, and five different plants (1.1%) were demonstrated to be transgenic following Southern hybridization. 相似文献
2.
Evolutionary patterns of sequence divergence were analyzed in genes from the conifer genus Taxus (yew), encoding paclitaxel biosynthetic enzymes taxadiene synthase (TS) and 10-deacetylbaccatin III-10β-O-acetyltransferase
(DBAT). N-terminal fragments of TS, full-length DBAT and internal transcribed spacer (ITS) were amplified from 15 closely related Taxus species and sequenced. Premature stop codons were not found in TS and DBAT sequences. Codon usage bias was not found, suggesting that synonymous mutations are selectively neutral. TS and DBAT gene trees are not consistent with the ITS tree, where species formed monophyletic clades. In fact, for both genes, alleles
were sometimes shared across species and parallel amino acid substitutions were identified. While both TS and DBAT are, overall, under purifying selection, we identified a number of amino acids of TS under positive selection based on inference using maximum likelihood models. Positively selected amino acids in the N-terminal
region of TS suggest that this region might be more important for enzyme function than previously thought. Moreover, we identify
lineages with significantly elevated rates of amino acid substitution using a genetic algorithm. These findings demonstrate
that the pattern of adaptive paclitaxel biosynthetic enzyme evolution can be documented between closely related Taxus species, where species-specific taxane metabolism has evolved recently. 相似文献
3.
Ophiodothella caseariae sp. nov. from leaves of Casearia tremula in Venezuela is described and illustrated.
Received: February 19, 2002 / Accepted: April 30, 2002 相似文献
4.
5.
A new species of Erysiphe sect. Uncinula is described and illustrated from Patagonia, Argentina. Erysiphe patagoniaca sp. nov., found on leaves of Nothofagus × antarctica, is similar to E. nothofagi and E. kenjiana, but differs in its appendages being twisted throughout their length and the number of appendages, asci, and ascospores.
The two endemic species of Erysiphe sect. Uncinula, E. magellanica and E. nothofagi, coexisted on the same leaves together with Erysiphe patagoniaca.
Received: September 19, 2002 / Accepted: November 28, 2002
Acknowledgments The authors are grateful to Ms. Seiko Niinomi for providing the micrographs of ascomata of Erysiphe spp. on Nothofagus.
Correspondence to:S. Takamatsu 相似文献
6.
7.
A protocol was developed for rapid and efficient production of transgenic celery plants via somatic embryo regeneration from
Agrobacterium tumefaciens- inoculated leaf sections, cotyledons and hypocotyls. These explants were excised from in vitro seedlings of the cvs. XP166
and XP85 and inoculated with A. tumefaciens strain EHA105 containing the binary vector pBISN1. PBISN1 has the neomycin phosphotransferase gene (nptII) and an intron interrupted β-glucuronidase (GUS) reporter gene (gusA). Co-cultivation was carried out for 4 d in the dark on callus induction medium (CIM): Gamborg B5 + 2.79 μM kinetin + 2.26 μM
2,4-dichlorophenoxyacetic acid (2,4-D) supplemented with 100 μM acetosyringone. Embryogenic calluses resistant to kanamycin
(Km) were then recovered on CIM + 25 mg l−1 Km + 250 mg l−1 timentin after 12 weeks. Subsequently, a large number of Km-resistant and GUS-positive transformants, tens to hundreds per
explant were regenerated via somatic embryogenesis on Gamborg B5 + 4.92 μM 6 (γ,γ-dimethylallylamino)-purine (2iP) + 1.93 μM
α-naphthaleneacetic acid (NAA) + 25 mg l−1 Km + 250 mg l−1 timentin after 8 weeks. Using this protocol, the transformation frequency was 5.0% and 5.0% for leaf sections, 17.8% and
18.3% for cotyledons, and 15.9% and 16.7% for hypocotyl explants of cvs. XP85 and XP166, respectively. Stable integration
of the model transgenes with 1–3 copy numbers was confirmed in all ten randomly selected transgenic events by Southern blot
analysis of gusA. Progeny analysis by histochemical GUS assay showed stable Mendelian inheritance of the transgenes. Thus, A. tumefaciens-mediated transformation of cotyledons or hypocotyls provides an effective and reproducible protocol for large-scale production
of transgenic celery plants. 相似文献
8.
H. Takahashi 《Mycoscience》2003,44(2):0103-0107
Three new species of Agaricales from eastern Honshu, Japan, are described and illustrated. (1) Clitocybe minutella sp. nov. (section Vernae), having white, very small, clitocyboid basidiomata with white, strigose mycelial tomentum at the base of the stipe and trichodermial
elements in the pileipellis, occurs on leaf litter in deciduous oak forests. (2) Crepidotus longicomatus sp.nov. (section Echinospori), forms very small (up to 3.5 mm in diameter), reniform basidiomata densely covered overall with white to pale yellow, erect,
thick-walled, long hairs. It has melleous, echinulate basidiospores, and was found on fallen dead branches in lowland oak
forests. (3) Crepidotus virgineus sp. nov. (section Crepidotus), forming pure white, reniform basidiomata, has smooth, ellipsoid basidiospores, subfusiform-pedicellate to irregularly cylindrical
cheilocystidia, and abundant clamp connections. It occurs on fallen dead branches in lowland oak forests.
Received: August 22, 2002 / Accepted: January 8, 2003
Acknowledgments I am grateful to Dr. Yousuke Degawa (KPM) for allowing the specimens cited to be kept in the Kanagawa Prefectural Museum
of Natural History.
Correspondence to:H. Takahashi 相似文献
9.
Kazumi Hosoya Hiroshi Ashiwa Masakazu Watanabe Ken-ya Mizuguchi Toshio Okazaki 《Ichthyological Research》2003,50(1):0001-0008
Two biological types of Japanese dark chub, so-called types A and B of Zacco temminckii, were taxonomically inspected. A comparison of types A and B with the lectotypes of Leuciscus sieboldii and L. temminckii in Siebold's collection revealed that type A is identical to L. sieboldii, whereas type B matches L. temminckii. Hence, Zacco sieboldii and Z. temminckii were redescribed on the basis of the lectotype and additional specimens from Japan. Zacco sieboldii is distinguishable from Z. temminckii by having a narrower band on the anterior portion of both body sides, nine branched rays of anal fin (10 in Z. temminckii), lateral line scales not less than 53 (not more than 52 in Z. temminckii), and scales above lateral line not less than 13 (not more than 11 in Z. temmincki). A key to the species of Japanese Zacco is also provided.
Received: August 15, 1999 / Revised: July 25, 2002 / Accepted: August 19, 2002
Acknowledgments We express our cordial thanks to all the following investigators: Dr. M.J.P. Van Oijen (RMNH) for the specimen loan of von
Siebold's collection; Professor San-Rin Jeon, Sang-Myung University (formerly, Seoul) for providing several papers on Korean
Zacco congeners; Dr. Harumi Sakai, National Fisheries University; Dr. Tetsuo Furukawa-Tanaka, Museum of Nature and Human Activities,
Hyogo; Dr. Seishi Kimura, Mie University; Dr. Akihisa Iwata, Kyoto University; Dr. Osamu Katano, National Research Institute
of Fisheries Sciences; Mr. Kazuo Hoshino, Oita Marine Palace; and Dr. Kouichi Kawamura, National Research Institute of Aquaculture,
for the valuable comments and information on the ecological aspects of both species of the Japanese dark chub.
Correspondence to:Kazumi Hosoya 相似文献
10.
Methyl oleate was used as a primary carbon source and as an alternative inducer for the production of an extracellular lipase,
Lip2, in Y. lipolytica strain LgX64.81 grown in a 20-l bioreactor. The lipase-encoding gene, LIP2, was investigated during culture on methyl oleate using a pLIP2–LacZ reporter fusion and we provide evidence for the involvement of methyl oleate in its regulation.
Revisions requested 7 July 2005; Revisions received 30 August 2005 相似文献
11.
Summary. A novel practical method for the synthesis of N-methyl-DL-aspartic acid 1 (NMA) and new syntheses for N-methyl-aspartic acid derivatives are described. NMA 1, the natural amino acid was synthesized by Michael addition of methylamine to dimethyl fumarate 5. Fumaric or maleic acid mono-ester and -amide were regioselectively transformed into beta-substituted aspartic acid derivatives.
In the cases of maleamic 11a or fumaramic esters 11b, the α-amide derivative 13 was formed, but hydrolysis of the product provided N-methyl-DL-asparagine 9 via base catalyzed ring closure to DL-α-methylamino-succinimide 4, followed by selective ring opening. Efficient methods were developed for the preparation of NMA-α-amide 13 from unprotected NMA via sulphinamide anhydride 15 and aspartic anhydride 3 intermediate products. NMA diamide 16 was prepared from NMA dimethyl ester 6 and methylamino-succinimide 4 by ammonolysis. Temperature-dependent side reactions of methylamino-succinimide 4 led to diazocinone 18, resulted from self-condensation of methylamino-succinimide via nucleophyl ring opening and the subsequent ring-transformation. 相似文献
12.
13.
The new flavonoid: herbacetin 3-O-β-glucopyranoside-8-O-β-glucuronopyranoside (1) together with known gossypetin 3-O-β-glucopyranoside
- 8-O-β-glucuronopyranoside (2) and isoscutellarein: 8-O-β-glucuronopyranoside (3) as well as 4′-methyl ether-8-O-β-glucuronopyranoside
(4), were isolated from the calyx and epicalyx leaves of Malope trifida and identified on the basis of their spectroscopic properties: UV, 1H and 13C NMR, ESI/MS. Two other flavonoids were identified as isoscutellarein: 3′-hydroxy 4′-methyl ether-8-O-β-glucuronoside (5)
and 8-O- rhamnoglucoside (6) on the basis of their UV and ESI/MS data. 相似文献
14.
B incompatibility factor mutants (Bmut) in Pleurotus ostreatus were recovered from common-B mating heterokaryons resulted from matings between wild-type monokaryons with different A but the same B factors (A1B2 and A2B2) after NTG mutagenesis. The mutant monokaryons such as A1B2mut and A2B2mut were observed to have regularly uninucleated hyphal cells and to be compatible with each other. Matings between A1B2mut and A2B2mut monokaryons produced stable heterokaryons (A1B2mut + A2B2mut) that had binucleated hyphal cells with true clamp connections and formed normal fruit-bodies. Mating tests using basidiospore
progeny from each of these heterokaryons revealed the bipolar mating pattern. Genetic analysis suggested that the mutation
of B factor in P. ostreatus might occur in the B incompatibility factor genes.
Received: August 3, 2001 / Accepted: January 18, 2002 相似文献
15.
16.
Chlamydospores of Entoloma clypeatum f. hybridum were described on the mycorrhizas and rhizomorphs associated with Rosa multiflora. Their developmental pattern seems to be the Nyctalis type. This is the first report on chlamydospore formation on the mycorrhizae in entolomatoid fungi.
Received: January 17, 2002 / Accepted: November 5, 2002
Acknowledgments K.H. is grateful to Emeritus Professor N. Sagara in Kyoto University, in whose laboratory part of this study was undertaken.
Thanks are due to Mr. D. Sakuma for allowing the specimens to be kept in Osaka Museum of Natural History.
Correspondence to:H. Kobayashi 相似文献
17.
Wiesława Bylka 《Acta Physiologiae Plantarum》2004,26(4):393-398
A new acetylated flavonol glycoside: patuletin 3-O-[5′″-O-feruloyl-β-D-apiofuransyl (1′″→2′′)-β-D-glucopyranoside] (2), together with a known patuletin 3-O-β-D-glucopyranoside (1) were isolated from the aerial part of Artiplex littoralis L. (Chenopodiacease). Their structures were elcidated by acid hydrolysis and spectroscopic methods including UV, 1H, 13C NMR and ESI-MS for both compounds, additionally 2D-NMR, HSQC, HMBC experiments were performed for 2. 相似文献
18.
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
19.
Qi Zhu Fengtao Wu Feng Ding Dong Ye Yongqin Chen Yi Li Yang Zhifan 《Plant Cell, Tissue and Organ Culture》2009,96(3):317-324
Dioscorea zingiberensis Wright has been cultivated as a pharmaceutical crop for production of diosgenin, a precursor for synthesis of various important
steroid drugs. Because breeding of D. zingiberensis through sexual hybridization is difficult due to its unstable sexuality and differences in timing of flowering in male and
female plants, gene transfer approaches may play a vital role in its genetic improvement. In this study, the Agrobacterium tumefaciens-mediated transformation of D. zingiberensis was investigated with leaves and calli as explants. The results showed that both leaf segments and callus pieces were sensitive
to 30 mg/l hygromycin and 50–60 mg/l kanamycin, and using calli as explants and addition of acetosyringone (AS) in cocultivation
medium were crucial for successful transformation. We first immersed callus explants in A. tumefaciens cells for 30 min and then transferred the explants onto a co-cultivation medium supplemented with 200 μM AS for 3 days. Three
days after, we cultured the infected explants on a selective medium containing 50 mg/l kanamycin and 100 mg/l timentin for
formation of kanamycin-resistant calli. After the kanamycin-resistant calli were produced, we transferred them onto fresh
selective medium for shoot induction. Finally, the kanamycin resistant shoots were rooted and the stable incorporation of
the transgene into the genome of D. zingiberensis plants was confirmed by GUS histochemical assay, PCR and Southern blot analyses. The method reported here can be used to
produce transgenic D. zingiberensis plants in 5 months and the transformation frequency is 24.8% based on the numbers of independent transgenic plants regenerated
from initial infected callus explants. 相似文献