共查询到20条相似文献,搜索用时 125 毫秒
1.
Hao Wei Richard Meilan Amy M. Brunner Jeffrey S. Skinner Caiping Ma Harish T. Gandhi Steven H. Strauss 《Molecular breeding : new strategies in plant improvement》2007,19(1):69-85
We tested the efficacy of an attenuation system developed to preclude the deleterious effects of floral promoter::cytotoxin
genes on vegetative growth of transgenic sterile plants. We tested the promoter (2.6 kb 5′ region) of the poplar LEAFY gene PTLF driving barstar, combined on the same T-DNA with barstar driven by either the CaMV 35S basal promoter +5 to −72 fragment (35SBP), 35SBP fused to the TMV omega element (35SBP omega), or the NOS promoter. The unattenuated pPTLF::barnase construct failed to give rise to any transgenic events, suggesting substantial non-reproductive expression from this promoter.
The barstar-attenuated constructs enabled transformation, but the rate was reduced by nearly one-third. Four events (7% of attenuated
events) had highly abnormal morphology, and were identified during the early phases of propagation; these events had significantly
higher barnase:barstar expression ratios based on quantitative RT-PCR. A greenhouse study showed that phenotypically normal attenuated plants grew
at the same rate as wild-type and barnase-lacking transgenic plants. A statistically significant positive linear association was found between relative growth rate
(RGR) and barstar:barnase ratio in the attenuated events, and graphical analysis suggested a threshold for barstar attenuation of barnase, above which additional levels of barstar did not provide further attenuation. Surprisingly, the appearance and growth rate of the nearly all of the attenuated events
were substantially reduced after one or two growing seasons in the field, and the extent of growth reduction was associated
with barstar:barnase expression ratio. These results demonstrate the importance of field testing during early phases of research to identify pleiotropic
effects of transgenic sterility genes in trees. 相似文献
2.
Gene containment technologies that prevent transgene dispersal through pollen, fruit and seed are in immediate demand to address
concerns of gene flow from transgenic crops into wild species or close relatives. In this study, we isolated the enhancer
element of Arabidopsis
AGAMOUS that drives gene expression specifically in stamens and carpels. By fusing this AG enhancer to a minimal 35S promoter fragment, two tissue-specific promoters, fAGIP and rAGIP in forward and reverse orientations, respectively, were created and fused to the GUS reporter. Transgenic Arabidopsis plants harboring either fAGIP::GUS or rAGIP::GUS displayed similar GUS expression specifically in carpel and stamen tissues and their primordial cells. To test their utility
for engineering sterility, the promoters were fused to the Diphtheria toxin A (DT-A) gene coding for a ribosome inactivating protein as well as the Barnase gene coding for an extracellular ribonuclease, and tested for tissue-specific ablation. Over 89% of AGIP::DT-A and 68% of AGIP::Barnase transgenic plants displayed specific and precise ablation of stamens and carpels and are completely sterile. These transgenic
plants showed normal vegetative development with prolonged vegetative growth. To evaluate the stability of the sterile phenotype,
16 AGIP::DT-A lines underwent two consecutive cutback generations and showed no reversion of the floral phenotype. This study demonstrates
a simple, precise and efficient approach to achieve absolute sterility through irreversible ablation of both male and female
floral organs. This approach should have a practical application for transgene containment in ornamental, landscaping, and
woody species, whose seeds and fruits are of no economic value. 相似文献
3.
Bego?a Garc��a-Sogo Benito Pineda Lourdes Castelblanque Teresa Ant��n M��nica Medina Edel��n Roque Claudia Torresi Jos�� P��o Beltr��n Vicente Moreno Luis Antonio Ca?as 《Plant cell reports》2010,29(1):61-77
Engineered male sterility in ornamental plants has many applications such as facilitate hybrid seed production, eliminate
pollen allergens, reduce the need for deadheading to extend the flowering period, redirect resources from seeds to vegetative
growth, increase flower longevity and prevent gene flow between genetically modified and related native plants. We have developed
a reliable and efficient Agrobacterium-mediated protocol for the genetic transformation of different Kalanchoe
blossfeldiana commercial cultivars. Transformation efficiency for cv. ‘Hillary’ was 55.3% whereas that of cv. ‘Tenorio’ reached 75.8%. Selection was carried
out with the nptII gene and increasing the kanamycin concentration from 25 to 100 mg l−1 allowed to reduced escapes from 50 to 60% to virtually 0%. This method was used to produce male-sterile plants through engineered
anther ablation. In our approach, we tested a male sterility chimaeric gene construct (PsEND1::barnase) to evaluate its effectiveness and effect on phenotype. No significant differences were found in the growth patterns between
the transgenic lines and the wild-type plants. No viable pollen grains were observed in the ablated anthers of any of the
lines carrying the PsEND1::barnase construct, indicating that the male sterility was complete. In addition, seed set was completely abolished in all the transgenic
plants obtained. Our engineered male-sterile approach could be used, alone or in combination with a female-sterility system,
to reduce the invasive potential of new ornamentals, which has become an important environmental problem in many countries. 相似文献
4.
Jagannath Arun Bandyopadhyay Panchali Arumugam N. Gupta Vibha Burma Pradeep Kumar Pental Deepak 《Molecular breeding : new strategies in plant improvement》2001,8(1):11-23
Male-sterile lines were generated in oilseed mustard (Brassica juncea) with a cytotoxic gene (barnase) in conjunction with either of two tapetum-specific promoters, TA29 and A9. Several transformation vectors based on different promoter and marker gene combinations were developed and tested for their efficacy in generating agronomically viable male-sterile lines. Use of strong constitutive promoters (e.g. CaMV 35S or its double-enhancer variant) to express the marker gene (bar) in barnase constructs generated male-sterile plants at an extremely low frequency with most plants showing abnormalities in vegetative morphology, poor female fertility, low seed germination frequencies and/or distortion in segregation ratios of transgenes. Such abnormalities were considerably reduced on using weaker promoters (e.g. nos) to drive the marker gene (nptII) in barnase constructs and could therefore be attributed to leaky expression of the barnase gene under enhancing effects of strong constitutive promoters. We show that the use of a Spacer DNA fragment between the barnase gene (driven by a tapetum-specific promoter) and the CaMV 35S promoter-driven bar gene insulates tissue-specific expression of the barnase gene over all developmental stages of transgenic plants and significantly enhances recovery of agronomically viable male-sterile lines. All TA29-barnase male-sterile lines containing the Spacer DNA fragment exhibited normal morphology, growth and seed set on backcrossing as observed for wild-type plants. Around 75% of single-copy events tested further also showed proper segregation of the marker gene/male-sterile phenotype among backcross progeny. Constructs based on the use of Spacer DNA fragments as insulators could be successfully used to alleviate limitations associated with transformation of plant systems using cytotoxic genes for development of agronomically viable male-sterile lines in crop plants and for cell/tissue ablation studies in general. 相似文献
5.
Zheng X Deng W Luo K Duan H Chen Y McAvoy R Song S Pei Y Li Y 《Plant cell reports》2007,26(8):1195-1203
Here we report the effect of the 35S promoter sequence on activities of the tissue- and organ-specific gene promoters in tobacco
plants. In the absence of the 35S promoter sequence the AAP2 promoter is active only in vascular tissues as indicated by expression of the AAP2:GUS gene. With the 35S promoter sequence in the same T-plasmid, transgenic plants exhibit twofold to fivefold increase in AAP2 promoter activity and the promoter becomes active in all tissue types. Transgenic plants hosting the ovary-specific AGL5:iaaM gene (iaaM coding an auxin biosynthetic gene) showed a wild-type phenotype except production of seedless fruits, whereas plants hosting
the AGL5:iaaM gene along with the 35S promoter sequence showed drastic morphological alterations. RT-PCR analysis confirms that the phenotype
was caused by activation of the AGL5:iaaM gene in non-ovary organs including roots, stems and flowers. When the pollen-, ovule- and early embryo-specific PAB5:barnase gene (barnase coding a RNase gene) was transformed, the presence of 35S promoter sequence drastically reduced transformation efficiencies.
However, the transformation efficiencies were restored in the absence of 35S promoter, indicating that the 35S promoter might
activate the expression of PAB5:barnase in non-reproductive organs such as calli and shoot primordia. Furthermore, if the 35S promoter sequence was replaced with
the NOS promoter sequence, no alteration in AAP2, AGL5 or PAB5 promoter activities was observed. Our results demonstrate that the 35S promoter sequence can convert an adjacent tissue-
and organ-specific gene promoter into a globally active promoter.
Xuelian Zheng and Wei Deng contributed equally to this work and are considered co-first authors. 相似文献
6.
Xiangbin Xu Jufang Bian Songbai Liu Hongmiao Song Nongnong Shi Yuezhi Tao Huizhong Wang 《Molecular breeding : new strategies in plant improvement》2011,27(3):337-346
The PROMOTION OF CELL SURVIVAL 1 (PCS1) gene, encoding an aspartic protease, has an important role in determining the fate of cells in embryonic development and
reproduction processes in Arabidopsis. To explore the potential function of the PCS1 gene in generating reproductive sterility, we placed the PCS1 gene under the control of an 1,869-bp nucleotide sequence from the 3′ end of the second intron (AG-I) of Arabidopsis AGAMOUS and CaMV 35S (–60) minimal promoter [AG-I-35S (–60)::PCS1], and introduced it into tobacco. RT–PCR results demonstrated that the PCS1 gene driven by AG-I-35S (–60) chimeric promoter was expressed only in anthers and carpels in the reproductive tissues of transgenic tobacco. Compared to
wild-type plants, all AG-I-35S (–60) and AG-I-35S (–60)::PCS1 transgenic lines showed a normal phenotype throughout the vegetative growth phase. However, during the reproductive stage,
most AG-I-35S (–60)::PCS1 transgenic plant anthers displayed delayed dehiscence, failed dehiscence, petalody and hypoplasia, and the pollen grains
had different shapes and sizes with a distorted, shrunken, or collapsed morphology. Moreover, three transgenic lines, PCS1-1,
PCS1-3 and PCS1-4, showed higher sterility than wild-type and AG-I-35S (–60) transgenic plants, respectively. These results showed that the construct of AG-I-35S (–60)::PCS1 was partially effective at preventing seed set and provided a novel sterility strategy. 相似文献
7.
Cheon BY Kim HJ Oh KH Bahn SC Ahn JH Choi JW Ok SH Bae JM Shin JS 《Transgenic research》2004,13(6):541-549
Erythropoietin (EPO) is a glycoprotein used for curing human anemia by regulating the differentiation of erythroid progenitors and the production of red blood cells. To examine the expression of recombinant EPO in plants, pPEV-EP21, in which human epo cDNA under the control of the CaMV 35S promoter, was introduced into tobacco and Arabidopsisvia Agrobacterium tumefaciens-mediated transformation. The RNA expression level of epo in the transgenic lines was initially estimated by Northern blot analysis. Two transgenic lines, which exhibited a high expression level of epo mRNA determined by Northern analysis, were chosen for Western blot analysis to examine the production of EPO proteins. Those two lines, EP21-12 and EP21-14, revealed detectable bands on the immunoblot. Interestingly, constitutive expression of the human epo gene affected the morphologies in transgenic plants such that vegetative growth of transgenic tobacco was retarded, and male sterility was induced in transgenic tobacco and ArabidopsisThese authors contributed equally to this work 相似文献
8.
To develop a new system for inducible male sterility without any modification of the floral architecture in tobacco plants, a mutated ethylene receptor gene Cm-ERS1/H70A was fused either to the tobacco Nin88 promoter known to function mainly in the tapetum and microspore or to the CaMV 35S promoter known to be a constitutive promoter. The fusion genes pNin88::Cm-ERS1/H70A and p35S::Cm-ERS1/H70A were introduced in tobacco plants, which generated two independent transformants. Transformants with 35S::Cm-ERS1/H70A produced less normal pollen and had modified floral architecture while those with Nin88::Cm-ERS1/H70A produced less normal pollen without modification of floral architecture. Histological observations of anthers at stage 2 showed that tapetum degeneration in NH70A #8 and H70A #2 transformants occurred later than in wild types, strongly indicating that the expression of the mutated gene was involved in this delay. These results suggest that the tapetum-specific expression of a mutated ethylene receptor gene is a potential strategy for inducing male sterility in transgenic plants. 相似文献
9.
The development of rapid and efficient strategies to generate selectable marker-free transgenic plants could help increase
the consumer acceptance of genetically modified (GM) plants. To produce marker-free transgenic plants without conditional
treatment or the genetic crossing of offspring, we have developed a rapid and convenient DNA excision method mediated by the
Cre/loxP recombination system under the control of a −46 minimal CaMV 35S promoter. The results of a transient expression assay showed
that −46 minimal promoter::Cre recombinase (−46::Cre) can cause the loxP-specific excision of a selectable marker, thereby connecting the 35S promoter and β-glucuronidase (GUS) reporter gene. Analysis of stable transgenic Arabidopsis plants indicated a positive correlation between loxP-specific DNA excision and GUS expression. PCR and DNA gel-blot analysis further revealed that nine of the 10 tested T1 transgenic lines carried both excised and nonexcised constructs in their genomes. In the subsequent T2 generation plants, over 30% of the individuals for each line were marker-free plants harboring the excised construct only.
These results demonstrate that the −46::Cre fusion construct can be efficiently and easily utilized for producing marker-free transgenic plants. 相似文献
10.
Fernando Villarreal Victoria Martín Alejandro Colaneri Nahuel González-Schain Mariano Perales Mariana Martín Cristina Lombardo Hans-Peter Braun Carlos Bartoli Eduardo Zabaleta 《Plant molecular biology》2009,70(4):471-485
Plant mitochondria include gamma-type carbonic anhydrases (γCAs) of unknown function. In Arabidopsis, the γCAs form a gene family of five members which all are attached to the NADH dehydrogenase complex (complex I) of the
respiratory chain. Here we report a functional analysis of gamma carbonic anhydrase 2 (CA2). The gene encoding CA2 is constitutively
expressed in all plant organs investigated but it is ten fold induced in flowers, particularly in tapetal tissue. Ectopic
expression of CA2 in Arabidopsis causes male sterility in transgenic plants. In normal anther development, secondary thickenings of the endothecial cell wall
cause anthers to open upon dehydration. Histological analyses revealed that abnormal secondary thickening prevents anther
opening in 35S::CA2 transgenic plants. CA2 abundance in transgenic plants is increased 2–3 fold compared to wild-type plants
as revealed by Western blotting analyses. Moreover, abundance of other members of the CA family, termed CA3 and CAL2, is increased
in transgenic plants. Oxygen uptake measurements revealed that respiration in transgenic plants is mainly based on NADH reduction
by the alternative NADH dehydrogenases present in plant mitochondria. Furthermore, the formation of reactive oxygen species
(ROS) is very low in transgenic plants. We propose that reduction in ROS inhibits H2O2 dependent lignin polymerization in CA2 over-expressing plants, thereby causing male sterility.
Gene bank accession number: AY085025 (At1g47260). 相似文献
11.
12.
Sasaki K Ito H Mitsuhara I Hiraga S Seo S Matsui H Ohashi Y 《Plant molecular biology》2006,62(4-5):753-768
The wound-induced expression of tpoxN1, encoding a tobacco peroxidase, is unique because of its vascular system-specific expression and insensitivity to known wound-signal compounds such as jasmonic acid, ethylene, and plant hormones [Sasaki et al. (2002) Plant Cell Physiol 43:108–117]. To study the mechanism of expression, the 2-kbp tpoxN1 promoter region and successive 5′-deletion of the promoter were introduced as GUS fusion genes into tobacco plants. Analysis of GUS activity in transgenic plants indicated that a vascular system-specific and wound-responsive cis-element (VWRE) is present at the −239/−200 region of the promoter. Gel mobility shift assays suggested that a nuclear factor(s) prepared from wounded tobacco stems binds a 14-bp sequence (−229/−215) in the −239/−200 region in a sequence-specific manner. A mutation in this 14-bp region of the −239 promoter fragment resulted in a considerable decrease in wound-responsive GUS activity in transgenic plants. An 11-bp sequence, which completely overlaps with the 14-bp sequence, was found in the 5′ distal region (−420/−410) and is thought to contribute to the wound-induced expression together with the 14-bp. The −114-bp core promoter of the tpoxN1 gene was indispensable for wound-induced expression, indicating that the 14-bp region is a novel wound-responsive cis-element VWRE, which may work cooperatively with other factors in the promoter. 相似文献
13.
We report in this study, an improved method for identifying male sterile–restorer combinations using the barnase–barstar system of pollination control for heterosis breeding in crop plants, as an alternative to the conventional line × tester
cross method. In this strategy, a transgenic male sterile barnase line was retransformed with appropriate barstar constructs. Double transformants carrying both the barnase and barstar genes were identified and screened for their male fertility status. Using this strategy, 66–90% of fertile retransformants
(restored events) were obtained in Brassica juncea using two different barstar constructs. Restored events were analysed for their pollen viability and copy number of the barstar gene. Around 90% of the restored events showed high pollen viability and ∼30% contained single copy integrations of the barstar gene. These observations were significantly different from those made in our earlier studies using line (barnase) × tester (barstar) crosses, wherein only two viable male sterile–restorer combinations were identified by screening 88 different cross-combinations.
The retransformation strategy not only generated several independent restorers for a given male sterile line from a single
transformation experiment but also identified potential restorers in the T0 generation itself leading to significant savings in time, cost and labour. Single copy restored plants with high pollen viability
were selfed to segregate male sterile (barnase) and restorer (barstar) lines in the T1 progeny which could subsequently be diversified into appropriate combiners for heterosis breeding. This strategy will be
particularly useful for crop plants where poor transformation frequencies and/or lengthy transformation protocols are a major
limitation. 相似文献
14.
Z. T. Li S. Dhekney M. Dutt M. van Aman J. Tattersall K. T. Kelley D. J. Gray 《In vitro cellular & developmental biology. Plant》2006,42(3):220-227
Summary A translational fusion between the enhanced green fluorescent protein (EGFP) and neomycin phosphotransferase (NPTH) genes
was used to optimize parameters influencing Agrobacterium-mediated transformation of Vitis vinifera L. cv. Thompson Seedless. The corresponding bifunctional protein produced from this EGFP/NPTH fusion gene allowed for a single
promoter to drive expression of both green fluorescence and kanamycin resistance, thus conserving promoter resources and climinating
potential promoter-promoter interactions. The fusion gene, driven by either a double cauliflower mosaic virus 35S (CaMV 35S)
promoter or a double cassava vein mosaic virus (CsVMV) promoter, was immobilized into Agrobacterium strain EHA 105. Somatic embryos capable of direct secondary embryogenesis were used as target tissues to recover transgenic
plants. Simultaneous visualization of GFP fluorescence and kanamycin selection of transgenic cells, tissues, somatic embryos,
and plants were achieved. GFP expression and recovery of embryogenic culture lines were used as indicators to optimize transformation
parameters. Preculturing of somatic embryos for 7 d on fresh medium prior to transformation minimized Agrobacterium-induced tissue browning/necrosis. Alternatively, browning/necrosis was reduced by adding 1 gl−1 of the antioxidant dithiothreitol (DTT) to post co-cultivation wash media. While combining preculture with antioxidant treatments
did not result in a synergistic improvement in response, either treatment resulted in recovery of more stable embryogenic
lines than did the control. A 48h co-cultivation period combined with 75 mgl−1 kanamycin in selection medium was optimal. DNA analysis confirmed stable integration of transgenes into the grape genome:
63% had single gene insertions, 27% had two inserts, and 7 and 3% had three and four inserts, respectively. Utilizing optimized
procedures, over 1400 stable independent transgenic embryogenic culture lines were obtained, of which 795 developed into whole
plants. Transgenic grapevines have exhibited normal vegetative morphology and stable transgene expression for over 5 yr. 相似文献
15.
The potential for transgene dispersal through pollen, fruit, and seed is an important argument against the release of genetically modified plants. One approach toward addressing the concerns of gene flow from transgenic crops into closely related wild species involves in the use of tissue-specific promoters to engineer male and/or female sterility. In this study, we investigated the potential of Barnase ectopic expression for engineering floral sterility. A 2.6?kb promoter region of floral binding protein 6 (FBP6) from Petunia hybrida was isolated and fused to a reporter gene encoding ??-glucuronidase (GUS). The construct was introduced into tobacco plants where GUS staining was detected ubiquitously throughout the various tissues. The expression pattern of FBP6 resembled AG promoters, i.e., weak promoter activity was found in vegetative tissues, and strong activity was found in the various floral organs including the carpels and stigma. Meanwhile,The pFBP6::Barnase construct was then cotransformed into tobacco along with the Barstar gene, encoding an enzymatic inhibitor of Barnase, which was expressed at low but ubiquitous levels. Although cotransformed tobacco plants showed near normal vegetative growth, 74% of transgenic plants exhibited stigma and style ablation, and 98% of flower buds abscised before opening. Further analyses confirmed that stigma and style ablation prevented fertilization of the flower, and abscission of the bud followed rapidly. Thus, this approach has advantages for those ornamental/landscaping species where the pollen and fruit represent pollutants of the urban environment (e.g., platanus and poplar). 相似文献
16.
Sergei F. Krasnyanski Jagdeep Sandhu Leslie L. Domier Dennis E. Buetow Schuyler S. Korban 《In vitro cellular & developmental biology. Plant》2001,37(4):427-433
Summary Two different promoters, a cauliflower mosaic virus (CaMV) 35S promoter with a 5′-untranslated leader sequence from alfalfa
mosaic virus RNA4 (designated as CaMV 35S/AMV) and an E-8 fruit-ripening-specific promoter, were compared to evaluate their
effects on expression of the uidA reporter gene in transgenic tomato plants. In order to generate sufficient numbers of transgenic tomato plants, both a reliable
regeneration system and an efficient Agrobacterium transformation protocol were developed using 8-d-old cotyledons of tomato (Lycopersicon ecsulentum Mill. cv. Swifty Belle). Two sets of constructs, both derivatives of the binary vector pBI121, were used in transformation
of tomato whereby the uidA gene was driven either by the CaMV 35S/AMV or the E-8 fruit-ripening-specific promoter. Southern blot hybridization confirmed
the stable integration of the chimeric uidA gene into the tomato genome. Fruit and leaf tissues were collected from T0 and T1 plants, and assayed for β-glucuronidase (GUS) enzyme activity. As expected, both vegetative and fruit tissues of transgenic
plants carrying the uidA gene under the control of CaMV 35S/AMV showed varying levels of GUS activity, while no expression was observed in vegetative
tissues of transgenic plants carrying the uidA gene driven by the E-8 promoter. All fruits from transgenic plants produced with both sets of constructs displayed expression
of the uidA gene. However, when this reporter gene was driven by the CaMV 35S/AMV, GUS activity levels were significantly higher than
when it was driven by the E-8 fruit-specific promoter. The presence/absence of the uidA gene in T1 plants segregated in a 3∶1 Mendelian ratio. 相似文献
17.
SBgLR (Solanum tuberosum genomic lysine-rich) gene was isolated from a potato genomic library using SB401 (S.
berthaultii 401) cDNA as probe. RT-PCR analysis of SBgLR gene expression profile and microscopic analysis of green fluorescent protein (GFP) expression in tobacco plants transformed
with SBgLR promoter-GFP reporters indicate that SBgLR is a pollen-specific gene. A series of 5′deletions of SBgLR promoter were fused to the β-glucuronidase (GUS) gene and stably introduced into tobacco plants. Histochemical and quantitative assays of GUS expression in transgenic
plants allowed us to localize an enhancer of SBgLR promoter to the region −345 to −269 relative to the translation start site. This 76 bp (−345 to −269) fragment enhanced GUS
expression in leaves, stems and roots when fused to −90/+6 CaMV 35S minimal promoter. Deletion analysis showed that a cis-element, which can repress gene expression in root hairs, was located in the region −345 to −311. Further study indicated
that the −269 to −9 region was sufficient to confer pollen-specific expression of GFP when fused to CaMV 35S enhancer.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Authors Zhihong Lang and Peng Zhou contributed equally to this work. 相似文献
18.
19.
An AGAMOUS intron‐driven cytotoxin leads to flowerless tobacco and produces no detrimental effects on vegetative growth of either tobacco or poplar 下载免费PDF全文
Wei Li Wei Hu Chu Fang Longzheng Chen Weibing Zhuang Lorenzo Katin‐Grazzini Richard J. McAvoy Karl Guillard Yi Li 《Plant biotechnology journal》2016,14(12):2276-2287
Flowerless trait is highly desirable for poplar because it can prevent pollen‐ and seed‐mediated transgene flow. We have isolated the second intron of PTAG2, an AGAMOUS (AG) orthologue from Populus trichocarpa. By fusing this intron sequence to a minimal 35S promoter sequence, we created two artificial promoters, fPTAG2I (forward orientation of the PTAG2 intron sequence) and rPTAG2I (reverse orientation of the PTAG2 intron sequence). In tobacco, expression of the β‐glucuronidase gene (uidA) demonstrates that the fPTAG2I promoter is non‐floral‐specific, while the rPTAG2I promoter is active in floral buds but with no detectable vegetative activity. Under glasshouse conditions, transgenic tobacco plants expressing the Diphtheria toxin A (DT‐A) gene driven by the rPTAG2I promoter produced three floral ablation phenotypes: flowerless, neuter (stamenless and carpel‐less) and carpel‐less. Further, the vegetative growth of these transgenic lines was similar to that of the wild‐type plants. In field trials during 2014 and 2015, the flowerless transgenic tobacco stably maintained its flowerless phenotype, and also produced more shoot and root biomass when compared to wild‐type plants. In poplar, the rPTAG2I::GUS gene exhibited no detectable activity in vegetative organs. Under field conditions over two growing seasons (2014 to the end of 2015), vegetative growth of the rPTAG2I::DT‐A transgenic poplar plants was similar to that of the wild‐type plants. Our results demonstrate that the rPTAG2I artificial promoter has no detectable activities in vegetative tissues and organs, and the rPTAG2I::DT‐A gene may be useful for producing flowerless poplar that retains normal vegetative growth. 相似文献