共查询到20条相似文献,搜索用时 31 毫秒
1.
Chikako Honda Shinnosuke Kusaba Takaaki Nishijima Takaya Moriguchi 《Plant Cell, Tissue and Organ Culture》2011,107(1):45-53
To manipulate the architecture of woody plants by controlling endogenous cytokinin levels, the isopentenyl transferase gene (ipt) from Agrobacterim
tumefaciens was introduced to kiwifruit using stable transformation. Consequently, eight transgenic lines were obtained. Transgenic shoots
harboring the ipt gene were recalcitrant to rooting under tissue-culture conditions; thus, their in vitro-cultivated shoots were directly grafted
onto potted wild-type kiwifruit seedlings to evaluate their morphological features, and three lines (tmr2-4, tmr2-G, tmr3-C)
were successfully grafted. The grafted transgenic plants had dwarfing and branching phenotypes, both of which are typical
features of cytokinin overproduction. In addition, the number of buds increased and internode length was shorter in the grafted
transgenic plants. The content of a precursor, trans-zeatin riboside, and an active cytokinin, trans-zeatin, increased in one transgenic line, in which the level of ipt gene expression was high, indicating that morphological changes were related to expression levels of the ipt gene and cytokinin content. Possibilities for potential utilization of the ipt gene in manipulating tree shape are discussed. 相似文献
2.
A cytokinin biosynthetic gene encoding isopentenyl transferase (ipt) was cloned with its native promoter from Agrobacterium tumefaciens and introduced into tobacco plants. Indolebutyric acid was applied in rooting medium and morphologically normal transgenic
tobacco plants were regenerated. Genetic analysis of self-fertilized progeny showed that a single copy of intact ipt gene had been integrated, and T2 progeny had become homozygous for the transgene. Stable inheritance of the intact ipt gene in T2 progeny was verified by Southern hybridization. Northern blot hybridization revealed that the expression of this ipt gene was confined in leaves and stems but undetectable in roots of the transgenic plants. Endogenous cytokinin levels in
the leaves and stems of the transgenic tobaccos were two to threefold higher than that of control, but in roots, both the
transgenic and control tobaccos had similar cytokinin levels. The elevated cytokinin levels in the transgenic tobacco leaves
resulted in delayed leaf senescence in terms of chlorophyll content without affecting the net photosynthetic rate. The root
growth and morphology of the plant were not affected in the transgenic tobacco. 相似文献
3.
D. V. Tereshonok A. Yu. Stepanova Yu. I. Dolgikh E. S. Osipova D. V. Belyaev G. R. Kudoyarova L. B. Vysotskaya B. B. Vartapetian 《Russian Journal of Plant Physiology》2011,58(5):799-807
The effect of enhanced cytokinin synthesis due to expression of the ipt gene from Agrobacterium tumefaciens on plant tolerance to root flooding was studied. Transgenic wheat (Triticum aestivum L.) plants carrying the ipt gene were more tolerant to flooding than wild-type plants. The effect of transformation was manifested in the higher yield
and less growth inhibition during flooding. The measurements of activities of antioxidant enzymes, superoxide dismutase and
catalase, as well as MDA content during flooding revealed differences between wild-type and transgenic plants that correlated
with their tolerance. These results point to the protective role of cytokinins during wheat root flooding. 相似文献
4.
Lisianthus [Eustoma grandiflorum (Raf.) Shinn] is a popular cut flower crop throughout the world, and the demand for this plant for cut flowers and potted
plants has been increasing worldwide. Recent advances in genetic engineering have enabled the transformation and regeneration
of plants to become a powerful tool for improvement of lisianthus. We have established a highly efficient plant regeneration
system and Agrobacterium-mediated genetic transformation of E. grandiflorum. The greatest shoot regeneration frequency and number of shoot buds per explant are observed on media supplemented with 6-Benzylaminopurine
(BAP) and α-Naphthalene acetic acid (NAA). We report an efficient plant regeneration system using leaf explants via organogenesis
with high efficiency of transgenic plants (15%) in culture of 11 weeks’ duration. Further ectopic expression of two MADS box
genes, LMADS1-M from lily (Lilium longiflorum) and OMADS1 from orchid (Oncidium Gower Ramsey), was performed in E. grandiflorum. Conversion of second whorl petals into sepal-like structures and alteration of third whorl stamen formation were observed
in the transgenic E. grandiflorum plants ectopically expressing 35S::LMADS1-M. 35S::OMADS1 transgenic E. grandiflorum plants flowered significantly earlier than non-transgenic plants. This is the first report on the ectopic expression of two
MADS box genes in E. grandiflorum using a simple and highly efficient gene transfer protocol. Our results reveal the potential for floral modification in E. grandiflorum through genetic transformation. 相似文献
5.
6.
MAT (multi-auto-transformation) vector system has been one of the strategies to excise the selection marker gene from transgenic
plants. Agrobacterium tumefaciens strain EHA105 harboring an ipt-type MAT vector, pNPI132, was used to produce morphologically normal transgenic Petunia hybrida ‘Dainty Lady’ employing isopentenyl transferase (ipt) gene as the selection marker gene. β-glucuronidase (GUS) gene was used as model gene of interest. Infected explants were cultured on Murashige and Skoog (MS) medium without plant
growth regulators (PGR) and antibiotics. Shoots showing extreme shooty phenotype (ESP) were produced from the adventitious
shoots separated from the explants. Visual selection was carried out until production of morphologically normal shoots (approximately
4 months after infection). Histochemical GUS assay detected GUS gene in both ESP and normal shoots. PCR analysis confirmed the presence of model gene (GUS gene) and excision of the selection marker (ipt) gene in the normal transgenic plants. The insertion sites (1–3 for ipt gene and 1–2 for GUS gene) were detected by Southern blot analysis using DIG-labeled probes of both genes. These results show that ipt-type MAT vector can be used successfully to produce marker-free transgenic Petunia hybrida plants on PGR- and antibiotic-free MS medium. 相似文献
7.
8.
Lai-Sheng Meng Xu-Dong Sun Fei Li Hai-Liang Liu Zhen-Hua Feng Jian Zhu 《Acta Physiologiae Plantarum》2010,32(2):315-324
9.
Sachiko Funayama-Noguchi Ko Noguchi Chie Yoshida Masayoshi Kawaguchi 《Journal of plant research》2011,124(1):155-163
Genes of CLE (CLAVATA3/ESR-related) family encode peptide ligands that regulate plant development in response to external stimuli such as rhizobial
infection and the nitrate application as well as various internal stimuli. To investigate whether LjCLE gene(s) may involve in plant response to inorganic phosphate (Pi), we analyzed Pi responses of 39 LjCLE genes in hydroponically grown Lotus japonicus plants (ecotype Miyakojima ‘MG-20’). Two LjCLE genes, LjCLE19 and 20, were up-regulated specifically and greatly in roots of L. japonicus by Pi addition to the hydroponic solution. When the external Pi level increased, expressions of LjCLE19 and 20 increased before the increase in the Pi content in plants. On the other hand, when the external Pi level decreased, the Pi
content in plants decreased first, then expression levels of LjCLE19 and 20 decreased. Based on our results, we discuss the relationship between LjCLE19 and 20 and the tissue Pi levels in plants. This is the first report showing induction of specific CLE genes by phosphate. 相似文献
10.
Mature seed-derived embryogenic calli of indica rice (Oryza sativa L. cv. PAU201) were induced on semisolid Murashige and Skoog medium supplemented with 2.5 mg dm−3 2,4-dichlorophenoxyacetic acid + 0.5 mg dm−3 kinetin + 560 mg dm−3 proline + 30 g dm−3 sucrose + 8 g dm−3 agar. Using OsglyII gene, out of 3180 calli bombarded, 32 plants were regenerated on medium containing hygromycin (30 mg dm−3). Histochemical GUS assay of the hygromycin selected calli revealed GUS expression in 50 % calli. Among the regenerants,
46.87 % were GUS positive. PCR analysis confirmed the presence of the transgene of 1 kb in 60 % of independent plants. Further,
these plants have been grown to maturity in glasshouse. In vitro screening for salt tolerance showed increase in fresh mass of OsglyII putative transgenic calli (185.4 mg) as compared to control calli (84.2 mg) on 90 mM NaCl after 15 d. When exposed to 150
mM NaCl, OsglyII putative transgenic plantlets showed normal growth while the non-transgenic control plantlets turned yellow and finally did
not survive. 相似文献
11.
S. Kumar Sunil Kumar S. P. Negi J. K. Kanwar 《In vitro cellular & developmental biology. Plant》2008,44(6):474-479
Callus cultures derived from leaf segments of chrysanthemum cultivar ‘Snow Ball’ which was susceptible to Septoria obesa were successfully used for in vitro selection for resistance to this pathogenic fungus. Resistant cell lines were selected by culturing callus on growth medium
containing various concentrations of S. obesa filtrate. Resistant calluses obtained after two cycles (30 d each cycle) of selection were used for plant regeneration. About
30% of the plants regenerated from the resistant calluses and 70–80% of the plants raised from cuttings had acquired considerable
resistance against the pathogen in the field. No phenotypic variation was observed in the selected regenerates. 相似文献
12.
Xiang Yu Misato Ohtani Miyako Kusano Nobuyuki Nishikubo Misa Uenoyama Taishi Umezawa Kazuki Saito Kazuo Shinozaki Taku Demura 《Molecular breeding : new strategies in plant improvement》2017,37(5):57
Recent environmental issues have increased the demand for woody biomass as a renewable resource for industry and energy. For a stable supply of woody biomass, it is critical to decrease the effects of abiotic stresses, such as drought and salinity, which hinder plant growth. For the goal to develop practical stress-tolerant trees, we generated transgenic poplar plants (P. tremula × tremuloides), in which a key Arabidopsis regulatory factor involved in stress responses, SNF1-related protein kinase 2C (AtSRK2C), or galactinol synthase 2 (AtGolS2), was overexpressed. Both types of transgenic poplar plants displayed higher tolerance to abiotic stresses, in comparison with nontransgenic plants, indicating that AtSRK2C and AtGolS2 can function in the abiotic stress response pathway of poplar. We also examined the expression profiles of ten poplar genes putatively homologous to well-known Arabidopsis stress response genes and found that several of the poplar genes showed different responses to abiotic stress from their Arabidopsis counterparts. Whereas the overexpression of AtSRK2C in transgenic Arabidopsis plants was reported to upregulate the expression of endogenous genes, the overexpression of AtSRK2C or AtGolS2 in transgenic poplar did not. Taken together, our findings suggest that the details of the underlying molecular mechanisms of the abiotic stress response may differ, but that the key regulatory factors in Arabidopsis and poplar have common features and are effective molecular targets for further breeding to enhance abiotic stress tolerance in poplar. 相似文献
13.
The Sho gene from Petunia hybrida encodes an enzyme for cytokinin synthesis. Here we report on the effects of Shogene expression on potato development. In contrast to transgenic potato expressing the Agrobacterium ipt gene, moderate Sho expression resulted in sufficient root development that allowed the cultivation of the Sho transformants in soil. The most pronounced effects detectable in these lines were an enhanced shoot production, delayed tuber
formation, significant reduction in tuber size, and inhibition of tuber dormancy. Sho expression predominantly associated with a strong increase in 2iP glucosides, accompanied by an increase in zeatin glucosides
in lines with very high Sho expression levels. The data demonstrate that it is possible to produce viable plants with enhanced cytokinin levels via constitutive Sho expression, which allows an assessment of cytokinin effects in all organs. 相似文献
14.
J. Purkayastha T. Sugla A. Paul S. K. Solleti P. Mazumdar A. Basu A. Mohommad Z. Ahmed L. Sahoo 《Biologia Plantarum》2010,54(1):13-20
An efficient and reproducible in vitro plant regeneration system from shoot apices was developed in Jatropha curcas. Benzylaminopurine (BAP; 2.5 μM) was most effective in inducing an average of 6.2 shoots per shoot apex. Incorporation of
gibberellic acid (GA3; 0.5 μM) to basal medium was found essential for elongation of shoots. The BAP-habituated mother explants
continuously produced shoots during successive subculture without any loss of morphogenic potential. The shoots rooted efficiently
on half-strength MS medium. The rooted plantlets were acclimatized with more than 98 % success and the plants transferred
to soil:compost in nursery showed no sign of variation compared to the seed-grown plants. The whole process of culture initiation
to plant establishment was accomplished within 5–6 weeks. A genetic transformation system in J. curcas was established for the first time, using bombardment of particles coated with plasmid pBI426 with a GUS-NPT II fusion protein
under the control of a double 35S cauliflower mosaic virus (CaMV) promoter. The β-glucuronidase (GUS) activity in J. curcas shoot apices was significantly affected by the gold particle size, bombardment pressure, target distance, macrocarrier travel
distance, number of bombardments, and type and duration of osmotic pre-treatment. The proliferating bombarded shoot apices
were screened on medium supplemented with 25 mg dm−3 kanamycin and surviving shoots were rooted on medium devoid of kanamycin. The integration of the transgene into genomic DNA
of transgenic plants was confirmed by PCR and Southern blot hybridization. The transgenic plants showed insertion of single
to multiple copies of the transgene. 相似文献
15.
16.
Gunaratnam Thirukkumaran Raham Sher Khan Dong Poh Chin Ikuo Nakamura Masahiro Mii 《Plant Cell, Tissue and Organ Culture》2009,97(3):237-242
The technologies allowing the production of transgenic plants without selectable marker genes, is of great interest in public
and environmental safety. For generating such marker-free transgenic plants, possibility has been offered by Multi-Auto-Transformation
[MAT] vector system, which combines positive selection, using the isopentenyl transferase (ipt) gene, with a site-specific recombination that generates marker-free plants. In this study Agrobacterium tumefaciens strain EHA105 harboring an ipt-type MAT vector, pMAT21, containing lacZ, gus genes and the removable cassette in the T-DNA region was used to produce marker-free transgenic Kalanchoe blossfeldiana Poelln., employing ipt gene as the selectable marker gene. Co-cultivated explants were cultured on hormone- and selective agent-free MS medium,
and 85% of the regenerated shoots showed ipt-shooty phenotype with GUS expression. Forty-one morphologically normal shoots were produced during the subculture. More than
ninety percent of the normal shoots were ipt
−, gus
− but lacZ
+ as determined by PCR analyses. These results indicate that the ipt phenotype was clearly distinguishable from non-transgenic as well as transgenic marker-free shoots. This study opens interesting
perspective for the generation of marker-free transgenic K. blossfeldiana with objective useful transgene. 相似文献
17.
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
18.
The presence of marker genes conferring antibiotic resistance in transgenic plants represents a serious obstacle for their
public acceptance and future commercialization. In addition, their elimination may allow gene stacking by the same selection
strategy. In apricot, selection using the selectable marker gene nptII, that confers resistance to aminoglycoside antibiotics, is relatively effective. An attractive alternative is offered by
the MAT system (multi-auto-transformation), which combines the ipt gene for positive selection with the recombinase system R/RS for removal of marker genes from transgenic cells after transformation. Transformation with an MAT vector has been attempted
in the apricot cultivar ‘Helena’. Regeneration from infected leaves with Agrobacterium harboring a plasmid containing the ipt gene was significantly higher than that from non-transformed controls in a non-selective medium. In addition, transformation
efficiencies were much higher than those previously reported using antibiotic selection, probably due to the integration of
the regeneration-promoting ipt gene. However, the lack of an ipt expression-induced differential phenotype in apricot made difficult in detecting the marker genes excision and plants had
to be evaluated at different times. PCR analysis showed that cassette excision start occurring after 6 months approximately
and 1 year in culture was necessary for complete elimination of the cassette in all the transgenic lines. Excision was confirmed
by Southern blot analysis. We report here for the first time in a temperate fruit tree that the MAT vector system improves
regeneration and transformation efficiency and would allow complete elimination of marker genes from transgenic apricot plants
by site-specific recombination. 相似文献
19.
Guangying Ma Guogui Ning Wei Zhang Jing Zhan Haiyan Lv Manzhu Bao 《Plant Molecular Biology Reporter》2011,29(3):573-581
FBP21 is one of the SOC1-like genes isolated from Petunia hybrida. Based on sequence analysis, FPB21 is suggested to have a role in promoting flowering. In this study, FBP21 was expressed in a tobacco host plant under the control of the CaMV 35S promoter. Our results showed that the transgene accelerated flowering, i.e. the transgenic plants flowered just 3 months
after germination, in comparison to the wild-type tobacco which flowered after 5 months. Plant morphology was also affected,
with the transgenic tobacco plants developing at least five robust lateral branches, while the control plants generally had
just three. Total leaf area was significantly reduced in the transgenic tobacco compared to wild-type tobacco. By contrast,
there was no significant difference between transgenic and control plants for the total number of flowers or fruits. Thus,
the flower or fruit yield expressed per unit leaf area was higher in transgenic tobacco than in wild-type plants. Semi-quantitative
RT-PCR analysis indicated that overexpression of FBP21 in tobacco resulted in the up-regulation of some flowering-related genes. The results of this study in tobacco indicate that
the Petunia FBP21 gene may permit the engineering of early-flowering and short-growth habits without compromising flower or fruit yields. 相似文献