scholarly journals Complementation of Coat Protein Mutants of Pepper Huasteco Geminivirus in Transgenic Tobacco Plants

1999 ◽  
Vol 89 (7) ◽  
pp. 540-545 ◽  
Author(s):  
R. G. Guevara-González ◽  
P. L. Ramos ◽  
R. F. Rivera-Bustamante
Keyword(s):  
Coat Protein ◽  
Transgenic Tobacco ◽  
Cauliflower Mosaic Virus ◽  
Wild Type Virus ◽  
35S Promoter ◽  
Wild Type ◽  
Tobacco Plants ◽  
Protein Mutants ◽  
Infectivity Analysis

The role of the pepper huasteco virus (PHV) coat protein (CP) gene during the infection was investigated in three different hosts by using mutations that produced truncated proteins and by complementation assays in transgenic plants. The infectivity analysis revealed that mutants that express truncated CP (CP7 and CP191) behave like the wild-type virus when inoculated onto pepper and Nicotiana benthamiana plants in terms of symptom expression and viral DNA movement. On the contrary, the CP7 mutant was unable to systemically infect tobacco plants, whereas only 10% of the plants inoculated with the CP191 mutant became infected. The CP7 mutant was complemented by coinoculating it with another geminivirus (taino tomato mottle virus). No complementation was observed in plants from nine transgenic tobacco lines expressing CP under the control of the cauliflower mosaic virus (CaMV) 35S promoter. However, 3 out of 10 lines expressing CP under the control of its own promoter (693 nucleotides) were able to complement the CP7 mutant. Interestingly, upon infection, the levels of CP mRNA in 693CP plants increased dramatically, probably due to transactivation of the CP promoter by the viral protein AC2.

scholarly journals Expression of soybean nodulin 26 in transgenic tobacco. Targeting to the vacuolar membrane and effects on floral and seed development.

1995 ◽  
Vol 6 (1) ◽  
pp. 109-117 ◽  
Author(s):  
Y Zhang ◽  
D M Roberts
Keyword(s):  
Transgenic Tobacco ◽  
Plasma Membranes ◽  
Pollen Viability ◽  
Physiological Effect ◽  
Cauliflower Mosaic Virus ◽  
35S Promoter ◽  
Subcellular Targeting ◽  
Western Blots ◽  
Tobacco Plants ◽  
Capsule Size

Nodulin 26 is an integral membrane protein of the symbiosome membrane of nitrogen-fixing soybean nodules. We expressed a nodulin 26 cDNA in transgenic tobacco (TN26 tobacco) under the control of the cauliflower mosaic virus 35S promoter to study subcellular targeting and the physiological effect(s) of its expression. Based on Northern and Western blots, the expression of nodulin 26 mRNA and protein in transgenic plants is high in apical shoot sections, flowers, and stems, low in mature leaves, and absent in roots. Western blot analysis revealed high levels of transgenic nodulin 26 protein in tonoplast membranes. In contrast, nodulin 26 protein was not found in isolated plasma membranes, the soluble fraction, nor in chloroplast and mitochondria-enriched membrane fractions. About 50-60% of the flowers and pods from TN26 tobacco plants abscised prematurely. Seed capsule size and seed fill per capsule from the remainder of surviving flowers were about 50% of that of control plants. Pollen viability was found to be normal, but flowers from TN26 tobacco plants showed shorter anther filaments compared with control plants. Normal seed production and capsule size was restored by manually crossing the stigmas from TN26 plants with isolated pollen from either transgenic or control plants. Thus, the aberrant filament growth could have resulted in the reproductive defects associated with the plants.

scholarly journals Rootstocks Overexpressing StNPR1 and StDREB1 Improve Osmotic Stress Tolerance of Wild-Type Scion in Transgrafted Tobacco Plants

2021 ◽  
Vol 22 (16) ◽  
pp. 8398
Author(s):  
Yasmine S. Hezema ◽  
Mukund R. Shukla ◽  
Alok Goel ◽  
Murali M. Ayyanath ◽  
Sherif M. Sherif ◽  
...  
Keyword(s):  
Osmotic Stress ◽  
Transgenic Tobacco ◽  
Physiological Status ◽  
Wild Type ◽  
Long Distance ◽  
Graft Union ◽  
Tobacco Plants ◽  
Osmotic Stress Tolerance ◽  
And Function ◽  
Gene Expression Levels

In grafted plants, the movement of long-distance signals from rootstocks can modulate the development and function of the scion. To understand the mechanisms by which tolerant rootstocks improve scion responses to osmotic stress (OS) conditions, mRNA transport of osmotic responsive genes (ORGs) was evaluated in a tomato/potato heterograft system. In this system, Solanum tuberosum was used as a rootstock and Solanum lycopersicum as a scion. We detected changes in the gene expression levels of 13 out of the 21 ORGs tested in the osmotically stressed plants; of these, only NPR1 transcripts were transported across the graft union under both normal and OS conditions. Importantly, OS increased the abundance of StNPR1 transcripts in the tomato scion. To examine mRNA mobility in transgrafted plants, StNPR1 and StDREB1 genes representing the mobile and non-mobile transcripts, respectively, were overexpressed in tobacco (Nicotiana tabacum). The evaluation of transgenic tobacco plants indicated that overexpression of these genes enhanced the growth and improved the physiological status of transgenic plants growing under OS conditions induced by NaCl, mannitol and polyethylene glycol (PEG). We also found that transgenic tobacco rootstocks increased the OS tolerance of the WT-scion. Indeed, WT scions on transgenic rootstocks had higher ORGs transcript levels than their counterparts on non-transgenic rootstocks. However, neither StNPR1 nor StDREB1 transcripts were transported from the transgenic rootstock to the wild-type (WT) tobacco scion, suggesting that other long-distance signals downstream these transgenes could have moved across the graft union leading to OS tolerance. Overall, our results signify the importance of StNPR1 and StDREB1 as two anticipated candidates for the development of stress-resilient crops through transgrafting technology.

scholarly journals Overexpression of the pitaya phosphoethanolamine N-methyltransferase gene (HpPEAMT) enhanced simulated drought stress in tobacco

2021 ◽  
Author(s):  
Ai-Hua Wang ◽  
Lan Yang ◽  
Xin-Zhuan Yao ◽  
Xiao-Peng Wen
Keyword(s):  
Drought Stress ◽  
Stress Response ◽  
Transgenic Plants ◽  
Drought Tolerance ◽  
Transgenic Tobacco ◽  
Sequence Similarity ◽  
Amino Acid Sequence Similarity ◽  
Transgenic Tobacco Plants ◽  
Wild Type ◽  
Tobacco Plants

AbstractPhosphoethanolamine N-methyltransferase (PEAMTase) catalyzes the methylation of phosphoethanolamine to produce phosphocholine and plays an important role in the abiotic stress response. Although the PEAMT genes has been isolated from many species other than pitaya, its role in the drought stress response has not yet been fully elucidated. In the present study, we isolated a 1485 bp cDNA fragment of HpPEAMT from pitaya (Hylocereus polyrhizus). Phylogenetic analysis showed that, during its evolution, HpPEAMT has shown a high degree of amino acid sequence similarity with the orthologous genes in Chenopodiaceae species. To further investigate the function of HpPEAMT, we generated transgenic tobacco plants overexpressing HpPEAMT, and the transgenic plants accumulated significantly more glycine betaine (GB) than did the wild type (WT). Drought tolerance trials indicated that, compared with those of the wild-type (WT) plants, the roots of the transgenic plants showed higher drought tolerance ability and exhibited improved drought tolerance. Further analysis revealed that overexpression of HpPEAM in Nicotiana tabacum resulted in upregulation of transcript levels of GB biosynthesis-related genes (NiBADH, NiCMO and NiSDC) in the leaves. Furthermore, compared with the wild-type plants, the transgenic tobacco plants displayed a significantly lower malondialdehyde (MDA) accumulation and higher activities of the superoxide dismutase (SOD) and peroxidase (POD) antioxidant enzymes under drought stress. Taken together, our results suggested that HpPEAMT enhanced the drought tolerance of transgenic tobacco.

scholarly journals The Avirulence Domain of Cauliflower mosaic virus Transactivator/Viroplasmin Is a Determinant of Viral Virulence in Susceptible Hosts

2004 ◽  
Vol 17 (5) ◽  
pp. 475-483 ◽  
Author(s):  
Kappei Kobayashi ◽  
Thomas Hohn
Keyword(s):  
Mosaic Virus ◽  
Host Plants ◽  
Datura Stramonium ◽  
Cauliflower Mosaic Virus ◽  
Wild Type Virus ◽  
Wild Type ◽  
Multifunctional Protein ◽  
Viral Virulence ◽  
Host Defense Response ◽  
Solanaceous Plants

Cauliflower mosaic virus (CaMV) transactivator/viroplasmin (Tav) is a multifunctional protein essential for basic replication of CaMV. It also plays a role in viral pathogenesis in crucifer and solanaceous host plants. Deletion mutagenesis revealed that N- and C-terminal parts of Tav are not essential for CaMV replication in transfected protoplasts. Two deletion mutants having only minimal defects in basic replication were infectious in turnips but only with highly attenuated virulence. This was shown to be due to delayed virus spread within the inoculated leaves and to the upper leaves. Unlike the wild-type virus, the mutant viruses successfully spread locally without inducing a host defense response in inoculated Datura stramonium leaves, but did not spread systemically. These results provide the first evidence that a Tav domain required for avirulence function in solanaceous plants is not essential for CaMV infectivity but has a role in viral virulence in susceptible hosts.

scholarly journals Comparative reactions of recombinant papaya ringspot viruses with chimeric coat protein (CP) genes and wild-type viruses on CP-transgenic papaya

2001 ◽  
Vol 82 (11) ◽  
pp. 2827-2836 ◽  
Author(s):  
Chu-Hui Chiang ◽  
Ju-Jung Wang ◽  
Fuh-Jyh Jan ◽  
Shyi-Dong Yeh ◽  
Dennis Gonsalves
Keyword(s):  
Coat Protein ◽  
Sequence Similarity ◽  
Transcriptional Gene Silencing ◽  
Papaya Ringspot Virus ◽  
Wild Type ◽  
Coding Region ◽  
Transgenic Papaya ◽  
Cp Gene ◽  
Post Transcriptional Gene Silencing

Transgenic papaya cultivars SunUp and Rainbow express the coat protein (CP) gene of the mild mutant of papaya ringspot virus (PRSV) HA. Both cultivars are resistant to PRSV HA and other Hawaii isolates through homology-dependent resistance via post-transcriptional gene silencing. However, Rainbow, which is hemizygous for the CP gene, is susceptible to PRSV isolates from outside Hawaii, while the CP-homozygous SunUp is resistant to most isolates but susceptible to the YK isolate from Taiwan. To investigate the role of CP sequence similarity in overcoming the resistance of Rainbow, PRSV HA recombinants with various CP segments of the YK isolate were constructed and evaluated on Rainbow, SunUp and non-transgenic papaya. Non-transgenic papaya were severely infected by all recombinants, but Rainbow plants developed a variety of symptoms. On Rainbow, a recombinant with the entire CP gene of YK caused severe symptoms, while recombinants with only partial YK CP sequences produced a range of milder symptoms. Interestingly, a recombinant with a YK segment from the 5′ region of the CP gene caused very mild, transient symptoms, whereas recombinants with YK segments from the middle and 3′ parts of the CP gene caused prominent and lasting symptoms. SunUp was resistant to all but two recombinants, which contained the entire CP gene or the central and 3′-end regions of the CP gene and the 3′ non-coding region of YK, and the resulting symptoms were mild. It is concluded that the position of the heterologous sequences in the recombinants influences their pathogenicity on Rainbow.

scholarly journals Lead Phytoremediation Potential of Wild Type and Transgenic Tobacco Plants

2021 ◽  
Vol 5 (1) ◽  
pp. 168-182
Author(s):  
Hatice DAGHAN ◽  
Veli UYGUR ◽  
Abdullah EREN
Keyword(s):  
Nicotiana Tabacum ◽  
Transgenic Tobacco ◽  
Transgenic Tobacco Plants ◽  
Wild Type ◽  
Tobacco Plants ◽  
Nicotiana Tabacum L ◽  
Lead Phytoremediation

Genetiği değiştirilmiş bitkiler, kurşunun (Pb) kökten yer üstü kısımlarına translokasyonunu geliştirmek için büyük bir potansiyele sahip olabilir. Transgenik olmayan ( Nicotiana tabacum L. cv. Petit Havana SR1) ve transgenik (p-cV-ChMTII GFP) tütün bitkileri tarafından Pb alımının sağlanması araştırmak için Çin hamsteri metalotiyonin II gezen bir kap deneyi yapıldı . Transgenik ve transgenik olmayan tütün bitkileri, 0, 1000, 2500, 5000 mg Pb kg- 1 ile Pb (NO 3 ) 2 olarak işlenmiş topraklarda yetiştirildi. Kelimede bir büyüme bölümünde 6 hafta boyunca çiçeklenme aşamasına kadar.Bitkilerin büyümesi, klorofil içeriği, mineral besin elementleri ve düşük glutatyon (GSH) bezleri, bitkilerin Pb alım potansiyeli ile birlikte incelenmiştir. Hem transgenik hem de transgenik olmayan bitkiler için Pb uygulamasındaki artışa bağlı olarak yer üstü biyokütle çevrildi aşamalı bir düşüş gözlendi. Yaprak besinlerinin bulaştığı, aşırı Pb işlemlerinden olumsuz etkilenmiştir, bunlardan en büyük düşüşü. Sürgün Pb yüksek derecesi 76.0 mg kg kadar ulaşan -1 transgenik ve 70.9 mg kg -1 transgenik olmayan bitkilerde. Pb alımı, p-cV-ChMTII GFP'nin tütün bitkisine aktarılmasıyla iyileştirildi; ancak, Pb fitoremediasyonunda yeterli değildi. 

scholarly journals Enhanced Biomass Yield of and Saccharification in Transgenic Tobacco Over-Expressing β-Glucosidase

Biomolecules ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 806
Author(s):  
Eun Jin Cho ◽  
Quynh Anh Nguyen ◽  
Yoon Gyo Lee ◽  
Younho Song ◽  
Bok Jae Park ◽  
...  
Keyword(s):  
Transgenic Tobacco ◽  
Biomass Yield ◽  
Thermotoga Maritima ◽  
Total Biomass ◽  
Transgenic Tobacco Plants ◽  
Wild Type ◽  
Tobacco Plants ◽  
Lignocellulose Conversion ◽  
Nicotiana Tabacum L ◽  
Genome Transcription

Here, we report an increase in biomass yield and saccharification in transgenic tobacco plants (Nicotiana tabacum L.) overexpressing thermostable β-glucosidase from Thermotoga maritima, BglB, targeted to the chloroplasts and vacuoles. The transgenic tobacco plants showed phenotypic characteristics that were significantly different from those of the wild-type plants. The biomass yield and life cycle (from germination to flowering and harvest) of the transgenic tobacco plants overexpressing BglB were 52% higher and 36% shorter than those of the wild-type tobacco plants, respectively, indicating a change in the genome transcription levels in the transgenic tobacco plants. Saccharification in biomass samples from the transgenic tobacco plants was 92% higher than that in biomass samples from the wild-type tobacco plants. The transgenic tobacco plants required a total investment (US$/year) corresponding to 52.9% of that required for the wild-type tobacco plants, but the total biomass yield (kg/year) of the transgenic tobacco plants was 43% higher than that of the wild-type tobacco plants. This approach could be applied to other plants to increase biomass yields and overproduce β-glucosidase for lignocellulose conversion.

scholarly journals The AC4 Protein of a Cassava Geminivirus Is Required for Virus Infection

2019 ◽  
Vol 32 (7) ◽  
pp. 865-875 ◽  
Author(s):  
Kegui Chen ◽  
Behnam Khatabi ◽  
Vincent N. Fondong
Keyword(s):  
Plant Viruses ◽  
Wild Type Virus ◽  
Virus Infectivity ◽  
Type Virus ◽  
Wild Type ◽  
Knockout Mutant ◽  
East African ◽  
Reading Frame ◽  
Cell Membrane Binding

Geminiviruses (family Geminiviridae) are among the most devastating plant viruses worldwide, causing severe damage in crops of economic and subsistence importance. These viruses have very compact genomes and many of the encoded proteins are multifunctional. Here, we investigated the role of the East African cassava mosaic Cameroon virus (EACMCV) AC4 on virus infectivity in Nicotiana benthamiana. Results showed that plants inoculated with EACMCV containing a knockout mutation in an AC4 open reading frame displayed symptoms 2 to 3 days later than plants inoculated with wild-type virus, and these plants recovered from infection, whereas plants inoculated with the wild-type virus did not. Curiously, when an additional mutation was made in the knockout mutant, the resulting double mutant virus completely failed to cause any apparent symptoms. Interestingly, the role of AC4 on virus infectivity appeared to be dependent on an encoded N-myristoylation motif that mediates cell membrane binding. We previously showed that EACMCV containing the AC4T38I mutant produced virus progeny characterized by second-site mutations and reversion to wild-type virus. These results were confirmed in this study using additional mutations. Together, these results show involvement of EACMCV AC4 in virus infectivity; they also suggest a role for the combined action of mutation and selection, under prevailing environmental conditions, on begomovirus genetic variation and diversity.

Sign in / Sign up

Export Citation Format

Share Document