Enhanced Salt Tolerance Conferred by the Complete 2.3 kb cDNA of the Rice Vacuolar Na+/H+ Antiporter Gene Compared to 1.9 kb Coding Region with 5′ UTR in Transgenic Lines of Rice

Class II high-affinity potassium transporters (HKT2s) mediate Na+–K+ cotransport and Na+/K+ homeostasis under K+-starved or saline conditions. Their functions have been studied in yeast and X. laevis oocytes; however, little is known about their respective properties in plant cells. In this study, we characterized the Na+ and K+ transport properties of SvHKT2;1, SvHKT2;2 and HvHKT2;1 in Arabidopsis under different ionic conditions. The differences were detected in shoot K+ accumulation and root K+ uptake under salt stress conditions, K+ accumulation in roots and phloem sap under K+-starved conditions, and shoot and root Na+ accumulation under K+-starved conditions among the HKT2s transgenic lines and WT plants. These results indicate the diverse ionic transport properties of these HKT2s in plant cells, which could not be detected using yeast or X. laevis oocytes. Furthermore, Arabidopsis expressing HKT2s showed reduced salt tolerance, while over-expression of HvHKT2;1 in barley, which has the ability to sequestrate Na+, showed enhanced salt tolerance by accumulating Na+ in the shoots. These results suggest that the coordinated enhancement of Na+ accumulation and sequestration mechanisms in shoots could be a promising strategy to confer salt tolerance to glycophytes.

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Analysis of recombination between viral RNAs and transgene mRNA under conditions of high selection pressure in favour of recombinants

Journal of General Virology ◽

10.1099/vir.0.013771-0 ◽

2009 ◽

Vol 90 (11) ◽

pp. 2798-2807 ◽

Cited By ~ 13

Author(s):

Marco Morroni ◽

Jeremy R. Thompson ◽

Mark Tepfer

Keyword(s):

Transgenic Plants ◽

Selection Pressure ◽

In Planta ◽

Coding Region ◽

Tobacco Plants ◽

Viral Rnas ◽

Transgenic Lines ◽

High Selection ◽

The One ◽

Viral Sequences

One possible environmental risk related to the utilization of virus-resistant transgenic plants expressing viral sequences is the emergence of new viruses generated by recombination between the viral transgene mRNA and the RNA of an infecting virus. This hypothesis has been tested recently for cucumber mosaic virus (CMV) by comparing the recombinant populations in transgenic and non-transgenic plants under conditions of minimal selection pressure in favour of the recombinants. Equivalent populations were observed in transgenic and non-transgenic plants but, in both, there was a strongly dominant hotspot recombinant which was shown recently to be nonviable alone in planta, suggesting that its predominance could be reduced by applying an increased selection pressure in favour of viable recombinants. Partially disabled I17F-CMV mutants were created by engineering 6 nt deletions in five sites in the RNA3 3′-non-coding region (3′-NCR). One mutant was used to inoculate transgenic tobacco plants expressing the coat protein and 3′-NCR of R-CMV. A total of 22 different recombinant types were identified, of which 12 were, as expected, between the transgene mRNA and the mutated I17F-CMV RNA3, while 10 resulted from recombination between the mutated RNA3 and I17F-CMV RNA1. Twenty recombinants were of the aberrant type, while two, including the dominant one detected previously under conditions of minimal selection pressure, were homologous recombinants. All recombinants detected were very similar to ones observed in nature, suggesting that the deployment of transgenic lines similar to the one studied here would not lead to the emergence of new viruses.

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A Novel Sweetpotato WRKY Transcription Factor, IbWRKY2, Positively Regulates Drought and Salt Tolerance in Transgenic Arabidopsis

Biomolecules ◽

10.3390/biom10040506 ◽

2020 ◽

Vol 10 (4) ◽

pp. 506 ◽

Cited By ~ 6

Author(s):

Hong Zhu ◽

Yuanyuan Zhou ◽

Hong Zhai ◽

Shaozhen He ◽

Ning Zhao ◽

...

Keyword(s):

Salt Tolerance ◽

Ipomoea Batatas ◽

Transgenic Arabidopsis ◽

Abiotic Stress Tolerance ◽

Wrky Transcription Factor ◽

Oxygen Species ◽

Aba Signaling ◽

Ros Scavenging ◽

Drought And Salt Tolerance ◽

Transgenic Lines

WRKYs play important roles in plant growth, defense regulation, and stress response. However, the mechanisms through which WRKYs are involved in drought and salt tolerance have been rarely characterized in sweetpotato [Ipomoea batatas (L.) Lam.]. In this study, we cloned a WRKY gene, IbWRKY2, from sweetpotato and its expression was induced with PEG6000, NaCl, and abscisic acid (ABA). The IbWRKY2 was localized in the nucleus. The full-length protein exhibited transactivation activity, and its active domain was located in the N-terminal region. IbWRKY2-overexpressing Arabidopsis showed enhanced drought and salt tolerance. After drought and salt treatments, the contents of ABA and proline as well as the activity of superoxide dismutase (SOD) were higher in transgenic plants, while the malondialdehyde (MDA) and H2O2 contents were lower. In addition, several genes related to the ABA signaling pathway, proline biosynthesis, and the reactive oxygen species (ROS)-scavenging system, were significantly up-regulated in transgenic lines. These results demonstrate that IbWRKY2 confers drought and salt tolerance in Arabidopsis. Furthermore, IbWRKY2 was able to interact with IbVQ4, and the expression of IbVQ4 was induced by drought and salt treatments. These results provide clues regarding the mechanism by which IbWRKY2 contributes to the regulation of abiotic stress tolerance.

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Generation of Transgenic Papaya with Double Resistance to Papaya ringspot virus and Papaya leaf-distortion mosaic virus

Phytopathology ◽

10.1094/phyto-99-11-1312 ◽

2009 ◽

Vol 99 (11) ◽

pp. 1312-1320 ◽

Cited By ~ 38

Author(s):

Yi-Jung Kung ◽

Huey-Jiunn Bau ◽

Yi-Ling Wu ◽

Chiung-Huei Huang ◽

Tsui-Miao Chen ◽

...

Keyword(s):

Mosaic Virus ◽

Field Tests ◽

Ringspot Virus ◽

Papaya Ringspot Virus ◽

Coding Region ◽

Transgenic Papaya ◽

Resistant Lines ◽

Transgenic Lines ◽

Chimeric Construct ◽

Leaf Distortion

During the field tests of coat protein (CP)-transgenic papaya lines resistant to Papaya ringspot virus (PRSV), another Potyvirus sp., Papaya leaf-distortion mosaic virus (PLDMV), appeared as an emerging threat to the transgenic papaya. In this investigation, an untranslatable chimeric construct containing the truncated CP coding region of the PLDMV P-TW-WF isolate and the truncated CP coding region with the complete 3′ untranslated region of PRSV YK isolate was transferred into papaya (Carica papaya cv. Thailand) via Agrobacterium-mediated transformation to generate transgenic plants with resistance to PLDMV and PRSV. Seventy-five transgenic lines were obtained and challenged with PRSV YK or PLDMV P-TW-WF by mechanical inoculation under greenhouse conditions. Thirty-eight transgenic lines showing no symptoms 1 month after inoculation were regarded as highly resistant lines. Southern and Northern analyses revealed that four weakly resistant lines have one or two inserts of the construct and accumulate detectable amounts of transgene transcript, whereas nine resistant lines contain two or three inserts without significant accumulation of transgene transcript. The results indicated that double virus resistance in transgenic lines resulted from double or more copies of the insert through the mechanism of RNA-mediated posttranscriptional gene silencing. Furthermore, three of nine resistant lines showed high levels of resistance to heterologous PRSV strains originating from Hawaii, Thailand, and Mexico. Our transgenic lines have great potential for controlling a number of PRSV strains and PLDMV in Taiwan and elsewhere.

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Ectopic Expression of a Thellungiella salsuginea Aquaporin Gene, TsPIP1;1, Increased the Salt Tolerance of Rice

International Journal of Molecular Sciences ◽

10.3390/ijms19082229 ◽

2018 ◽

Vol 19 (8) ◽

pp. 2229 ◽

Cited By ~ 8

Author(s):

Wei Li ◽

Xiao-Jing Qiang ◽

Xiao-Ri Han ◽

Lin-Lin Jiang ◽

Shu-Hui Zhang ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Small Molecules ◽

Differentially Expressed Genes ◽

Osmotic Potential ◽

Soluble Sugars ◽

Ectopic Expression ◽

Differentially Expressed ◽

Thellungiella Salsuginea ◽

Transgenic Lines

Aquaporins play important regulatory roles in the transport of water and small molecules in plants. In this study, a Thellungiella salsuginea TsPIP1;1 aquaporin was transformed into Kitaake rice, and three transgenic lines were evaluated by profiling the changes of the physiological metabolism, osmotic potential, and differentially expressed genes under salt stress. The TsPIP1;1 protein contains six transmembrane domains and is localized in the cytoplasm membrane. Overexpression of the TsPIP1;1 gene not only increased the accumulation of prolines, soluble sugars and chlorophyll, but also lowered the osmotic potential and malondialdehyde content in rice under salt stress, and alleviated the amount of salt damage done to rice organs by regulating the distribution of Na/K ions, thereby promoting photosynthetic rates. Transcriptome sequencing confirmed that the differentially expressed genes that are up-regulated in rice positively respond to salt stimulus, the photosynthetic metabolic process, and the accumulation profiles of small molecules and Na/K ions. The co-expressed Rubisco and LHCA4 genes in rice were remarkably up-regulated under salt stress. This data suggests that overexpression of the TsPIP1;1 gene is involved in the regulation of water transport, the accumulation of Na/K ions, and the translocation of photosynthetic metabolites, thus conferring enhanced salt tolerance to rice.

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Overexpression of HbMBF1a, encoding multiprotein bridging factor 1 from the halophyte Hordeum brevisubulatum, confers salinity tolerance and ABA insensitivity to transgenic Arabidopsis thaliana

Plant Molecular Biology ◽

10.1007/s11103-019-00926-7 ◽

2019 ◽

Vol 102 (1-2) ◽

pp. 1-17 ◽

Cited By ~ 5

Author(s):

Lili Zhang ◽

Yunxiao Wang ◽

Qike Zhang ◽

Ying Jiang ◽

Haiwen Zhang ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Salt Tolerance ◽

Transgenic Plants ◽

Growth Yield ◽

Transcript Levels ◽

Transgenic Lines ◽

Important Regulator ◽

Stress Responsive Genes ◽

Aba Insensitive ◽

Hordeum Brevisubulatum

Abstract Key message HbMBF1a was isolated and characterized in H. brevisubulatum, and overexpressed HbMBF1a could enhance the salt tolerance and ABA insensitivity in Arabidopsis thaliana. The transcript levels of stress-responsive genes were significantly increased in the transgenic lines under salt and ABA conditions. Abstract Salinity is an abiotic stress that considerably affects plant growth, yield, and distribution. Hordeum brevisubulatum is a halophyte that evolved to become highly tolerant to salinity. Multiprotein bridging factor 1 (MBF1) is a transcriptional coactivator and an important regulator of stress tolerance. In this study, we isolated and characterized HbMBF1a based on the transcriptome data of H. brevisubulatum grown under saline conditions. We overexpressed HbMBF1a in Arabidopsis thaliana and compared the phenotypes of the transgenic lines and the wild-type in response to stresses. The results indicated that HbMBF1a expression was induced by salt and ABA treatments during the middle and late stages. The overexpression of HbMBF1a in A. thaliana resulted in enhanced salt tolerance and ABA insensitivity. More specifically, the enhanced salt tolerance manifested as the increased seed germination and seedling growth and development. Similarly, under ABA treatments, the cotyledon greening rate and seedling root length were higher in the HbMBF1a-overexpressing lines, suggesting the transgenic plants were better adapted to high exogenous ABA levels. Furthermore, the transcript levels of stress-responsive genes were significantly increased in the transgenic lines under salt and ABA conditions. Thus, HbMBF1a is a positive regulator of salt and ABA responses, and the corresponding gene may be useful for producing transgenic plants that are salt tolerant and/or ABA insensitive, with few adverse effects. This study involved a comprehensive analysis of HbMBF1a. The results may provide the basis and insight for the application of MBF1 family genes for developing stress-tolerant crops.

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Genetic transformation and expression of transgenic lines of Populus x euramericana with insect-resistance and salt-tolerance genes

Genetics and Molecular Research ◽

10.4238/gmr.15028635 ◽

2016 ◽

Vol 15 (2) ◽

Cited By ~ 5

Author(s):

R.L. Yang ◽

A.X. Wang ◽

J. Zhang ◽

Y. Dong ◽

M.S. Yang ◽

...

Keyword(s):

Salt Tolerance ◽

Genetic Transformation ◽

Insect Resistance ◽

Transgenic Lines ◽

Populus X Euramericana

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Overexpression of miR5505 enhanced drought and salt resistance in rice (Orayza sativa)

10.1101/2022.01.13.476146 ◽

2022 ◽

Author(s):

YUANWEI FAN ◽

Fantao Zhang ◽

Jiankun Xie

Keyword(s):

Salt Tolerance ◽

Stress Responses ◽

High Throughput Sequencing ◽

Salt Resistance ◽

World Population ◽

Cis Acting ◽

Drought And Salt Tolerance ◽

The World ◽

Transgenic Lines ◽

Dongxiang Wild Rice

Rice is one of the most important crops in the world and half of the world population consumes it as their staple food. The abiotic stresses caused by drought, salt and other stresses have severely impacted rice production. MicroRNAs (miRNAs) are a type of small non-coding RNAs which widely reported as gene regulators, suppressing genes expression by degradation mRNA or translation inhibition. Previously, high-throughput sequencing has found a conserved miRNA miR5505 responding to drought stress in Dongxiang wild rice (DXWR). Several other studies also revealed that miR5505 was involved in rice stress responses. We further studied the effect of miRNA in drought and salt tolerance by overexpression it in rice. 2 in 18 successfully transformed transgenic lines with higher miR5505 expression were selected and then drought and salt resistance ability were evaluated. Both transgenic lines showed stronger drought and salt tolerance than wild-type (WT). Putative targets of miR5505 were identified by psRNATarget and several of them were found stress-related. RNA-seq found 1,980 differentially expressed genes (DEGs) in transgenic lines. Among them, 978 genes were down-regulated. Three genes were predicted by psRNATarget and two of them might be stress-related. We also found various environmental stress cis-acting elements in upstream of miR5505 promoter through Software PlantCARE. In all, we improved rice drought and salt tolerance by overexpressing miR5505, and the generated putative targets and cis-acting elements also suggested miR5505 might play important roles in the regulation of drought and salt responses. Keywords: rice, overexpression line , drought and salt stress, miR5505

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Comparative miRomics of Salt-Tolerant and Salt-Sensitive Rice

Journal of Integrative Bioinformatics ◽

10.1515/jib-2017-0002 ◽

2017 ◽

Vol 14 (1) ◽

Cited By ~ 8

Author(s):

Kavita Goswami ◽

Anita Tripathi ◽

Neeti Sanan-Mishra

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Transcriptional Level ◽

Tolerance Mechanism ◽

Quantitative Property ◽

Ionic Stress ◽

Plant Phenotype ◽

Transcript Cleavage ◽

Transgenic Lines ◽

Transcription Regulators

AbstractIncrease in soil salt causes osmotic and ionic stress to plants, which inhibits their growth and productivity. Rice production is also hampered by salinity and the effect of salt is most severe at the seedling and reproductive stages. Salainity tolerance is a quantitative property controlled by multiple genes coding for signaling molecules, ion transporters, metabolic enzymes and transcription regulators. MicroRNAs are key modulators of gene-expression that act at the post-transcriptional level by translation repression or transcript cleavage. They also play an important role in regulating plant’s response to salt-stress. In this work we adopted the approach of comparative and integrated data-mining to understand the miRNA-mediated regulation of salt-stress in rice. We profiled and compared the miRNA regulations using natural varieties and transgenic lines with contrasting behaviors in response to salt-stress. The information obtained from sRNAseq, RNAseq and degradome datasets was integrated to identify the salt-deregulated miRNAs, their targets and the associated metabolic pathways. The analysis revealed the modulation of many biological pathways, which are involved in salt-tolerance and play an important role in plant phenotype and physiology. The end modifications of the miRNAs were also studied in our analysis and isomiRs having a dynamic role in salt-tolerance mechanism were identified.

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Overexpression of TaBADH increases salt tolerance in Arabidopsis

Canadian Journal of Plant Science ◽

10.1139/cjps-2018-0190 ◽

2019 ◽

Vol 99 (4) ◽

pp. 546-555 ◽

Cited By ~ 1

Author(s):

Yinglu Sun ◽

Xin Liu ◽

Lianshuang Fu ◽

Peng Qin ◽

Tong Li ◽

...

Keyword(s):

Salt Tolerance ◽

Root Length ◽

Soil Salinization ◽

Betaine Aldehyde Dehydrogenase ◽

Wild Type ◽

Breeding Method ◽

Wild Type Line ◽

Transgenic Lines ◽

Plant Salt Tolerance ◽

Badh Gene

Soil salinization is an important threat to wheat growth and production. Previous transcriptome analysis showed that the expression of the betaine aldehyde dehydrogenase (BADH) gene differed significantly between cultivars with strong or weak salinity tolerance. Herein, the BADH gene from the wheat cultivar Dongnongdongmai 1 was cloned and transformed into wild-type Arabidopsis to identify its function in salt tolerance. Root length was calculated at 0, 50, 100, 150, and 200 mmol L−1 NaCl for 7 d. The relative electrolytic leakage (REL), GB content, and BADH activity were measured at 150 mmol L−1 NaCl for 1 and 3 d. It was determined that BADH activity and the GB content of TaBADH-overexpressed transgenic (TaBADHOE) lines were significantly higher than in wild-type lines. Salt stress analysis showed that the root length of TaBADHOE lines 4, 18, and 19 were 0.44, 0.54, and 0.35 cm, respectively, which were significantly longer than the 0.24 cm roots of the wild-type line in the media containing 150 mmol L−1 NaCl for 7 d. In addition, the RELs of transgenic lines 4, 18, and 19 were 0.37, 0.33, and 0.42, respectively, which is significantly lower than the 0.63 of the wild-type line in media containing 150 mmol L−1 NaCl for 3 d. These results demonstrate that TaBADH significantly increased plant salt tolerance, indicating that genetic transformation of TaBADH may be an effective and sustainable breeding method for increasing salt tolerance in wheat cultivars.

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