Overexpression of ZNT1 and NRAMP4 from the Ni Hyperaccumulator Noccaea caerulescens Population Monte Prinzera in Arabidopsis thaliana Perturbs Fe, Mn, and Ni Accumulation

Metalliferous soils are characterized by a high content of metal compounds that can hamper plant growth. The pseudometallophyte Noccaea caerulescens is able to grow on metalliferous substrates by implementing both tolerance and accumulation of usually toxic metal ions. Expression of particular transmembrane transporter proteins (e.g., members of the ZIP and NRAMP families) leads to metal tolerance and accumulation, and its comparison between hyperaccumulator N. caerulescens with non-accumulator relatives Arabidopsis thaliana and Thlaspi arvense has deepened our knowledge on mechanisms adopted by plants to survive in metalliferous soils. In this work, two transporters, ZNT1 and NRAMP4, expressed in a serpentinic population of N. caerulescens identified on the Monte Prinzera (Italy) are considered, and their expression has been induced in yeast and in A. thaliana. In the latter, single transgenic lines were crossed to test the effect of the combined over-expression of the two transporters. An enhanced iron and manganese translocation towards the shoot was induced by overexpression of NcZNT1. The combined overexpression of NcZNT1 and NcNRAMP4 did perturb the metal accumulation in plants.

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(288) An Arabidopsis thaliana Phytochelatin Synthase (AtPCS1) Gene Expressed in Transgenic Indian Mustard Contributes Partial Tolerance to Cd and Zn

HortScience ◽

10.21273/hortsci.40.4.1080e ◽

2005 ◽

Vol 40 (4) ◽

pp. 1080E-1081

Author(s):

Ksenija Gasic ◽

Schuyler S. Korban

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Arabidopsis Thaliana ◽

Metal Tolerance ◽

Heavy Metal Tolerance ◽

Indian Mustard ◽

35S Promoter ◽

Phytochelatin Synthase ◽

Mrna Accumulation ◽

Transgenic Lines

Phytochelatins (PCs) are heavy metal binding peptides that play important roles in sequestration and detoxification of heavy metals in plants. To develop transgenic plants with increased tolerance and/or accumulation of heavy metals from soil, an Arabidopsis thaliana FLAG–tagged AtPCS1 cDNA encoding phytochelatin synthase (PCS) under the control of a 35S promoter was expressed in Indian mustard (Brassica juncea). Four transgenic Indian mustard lines, designated pc lines, with different levels of AtPCS1 mRNA accumulation and correspondent AtPCS1 protein levels were selected and analyzed for tolerance to cadmium (Cd) and zinc (Zn). Heavy metal tolerance was assessed by measuring root length of 10-day-old seedlings grown on agar medium supplemented with different concentrations of Cd (0, 100, 150, and 200 μm CdCl2) and Zn (200, 400, 600, and 800 μm ZnCl2). All transgenic lines showed significantly longer roots when grown on a medium supplemented with 100 μm CdCl2. No significant differences were observed between transgenic lines and wild type when plants were grown on higher levels of Cd. This indicated that only partial tolerance to Cd was observed in these transgenic lines. Similarly, partial tolerance for Zn was also observed in these transgenic lines, but up to levels of 400 μm ZnCl2. Expression levels of AtPCS1 protein were not related to tolerance responses for either Cd or Zn stresses in transgenic lines.

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Heavy Metal Tolerance and Biotransformation of Toxic Metal Compounds by New Isolates of Wood-Rotting Fungi from Thailand

Geomicrobiology Journal ◽

10.1080/01490451.2015.1048394 ◽

2016 ◽

Vol 33 (3-4) ◽

pp. 283-288 ◽

Cited By ~ 14

Author(s):

Benjawan Kaewdoung ◽

Thanawat Sutjaritvorakul ◽

Geoffrey M. Gadd ◽

Anthony J.S. Whalley ◽

Prakitsin Sihanonth

Keyword(s):

Heavy Metal ◽

Metal Tolerance ◽

Heavy Metal Tolerance ◽

Toxic Metal ◽

Metal Compounds

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Over-Expression of a NAD-Malic Enzyme Gene from Rice in Arabidopsis thaliana Confers Tolerances to Several Abiotic Stresses

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.393-395.863 ◽

2011 ◽

Vol 393-395 ◽

pp. 863-866 ◽

Cited By ~ 1

Author(s):

Hao Zhou ◽

Shen Kui Liu ◽

Chuan Ping Yang

Keyword(s):

Arabidopsis Thaliana ◽

Abiotic Stresses ◽

Malic Enzyme ◽

Expression Vector ◽

Enzyme Gene ◽

Over Expression ◽

Plant Expression Vector ◽

Malic Enzyme Gene ◽

Transgenic Lines

In order to investigate the role of a rice NAD-malic enzyme gene (OsNAD-ME1) under different abiotic stresses, OsNAD-ME1 was constructed into plant expression vector and transformed into Agrobacterium for infecting Arabidopsis thaliana. There were higher transcriptional levels of OsNAD-ME1 in homozygous transgenic lines compared with WT plants as well as higher NAD-ME activity. WT and transgenic Arabidopsis were treated with NaCl, NaHCO3, mannitol and H2O2. And then their root lengths, crown widths and fresh weights were measured and compared. The results showed that over-expression of OsNAD-ME1 in transgenic Arabidopsis increased the resistance to abiotic stresses, which indicated that OsNAD-ME1 was related to stress tolerance.

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Root and Shoot Response to Nickel in Hyperaccumulator and Non-Hyperaccumulator Species

Plants ◽

10.3390/plants10030508 ◽

2021 ◽

Vol 10 (3) ◽

pp. 508

Author(s):

Stefano Rosatto ◽

Mauro Mariotti ◽

Sara Romeo ◽

Enrica Roccotiello

Keyword(s):

Plant Development ◽

Root Surface ◽

Metal Stress ◽

Physiological Conditions ◽

Thlaspi Arvense ◽

Noccaea Caerulescens ◽

Spiked Soil ◽

Ecophysiological Response ◽

Fluorescence Of Chlorophyll A ◽

Root Surfaces

The soil–root interface is the micro-ecosystem where roots uptake metals. However, less than 10% of hyperaccumulators’ rhizosphere has been examined. The present study evaluated the root and shoot response to nickel in hyperaccumulator and non-hyperaccumulator species, through the analysis of root surface and biomass and the ecophysiological response of the related aboveground biomass. Ni-hyperaccumulators Alyssoides utriculata (L.) Medik. and Noccaea caerulescens (J. Presl and C. Presl) F.K. Mey. and non-hyperaccumulators Alyssum montanum L. and Thlaspi arvense L. were grown in pot on Ni-spiked soil (0–1000 mg Ni kg−1, total). Development of root surfaces was analysed with ImageJ; fresh and dry root biomass was determined. Photosynthetic efficiency was performed by analysing the fluorescence of chlorophyll a to estimate the plants’ physiological conditions at the end of the treatment. Hyperaccumulators did not show a Ni-dependent decrease in root surfaces and biomass (except Ni 1000 mg kg−1 for N. caerulescens). The non-hyperaccumulator A. montanum suffers metal stress which threatens plant development, while the excluder T. arvense exhibits a positive ecophysiological response to Ni. The analysis of the root system, as a component of the rhizosphere, help to clarify the response to soil nickel and plant development under metal stress for bioremediation purposes.

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Influence of over-expression of cytosolic aspartate aminotransferase on amino acid metabolism and defence responses against Botrytis cinerea infection in Arabidopsis thaliana

Journal of Plant Physiology ◽

10.1016/j.jplph.2011.05.012 ◽

2011 ◽

Vol 168 (15) ◽

pp. 1813-1819 ◽

Cited By ~ 39

Author(s):

Sigrid Brauc ◽

Eline De Vooght ◽

Martine Claeys ◽

Monica Höfte ◽

Geert Angenon

Keyword(s):

Arabidopsis Thaliana ◽

Amino Acid ◽

Botrytis Cinerea ◽

Aspartate Aminotransferase ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Over Expression ◽

Defence Responses

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Over-expression of the rice OsAMT1-1 gene increases ammonium uptake and content, but impairs growth and development of plants under high ammonium nutrition

Functional Plant Biology ◽

10.1071/fp05165 ◽

2006 ◽

Vol 33 (2) ◽

pp. 153 ◽

Cited By ~ 50

Author(s):

Mohammad S. Hoque ◽

Josette Masle ◽

Michael K. Udvardi ◽

Peter R. Ryan ◽

Narayana M. Upadhyaya

Keyword(s):

Transgenic Plants ◽

Ammonium Assimilation ◽

Ammonium Transporter ◽

Ammonium Uptake ◽

Vegetative Stage ◽

Over Expression ◽

Transgenic Lines ◽

Ammonium Nutrition ◽

Maize Ubiquitin Promoter

A transgenic approach was undertaken to investigate the role of a rice ammonium transporter (OsAMT1-1) in ammonium uptake and consequent ammonium assimilation under different nitrogen regimes. Transgenic lines overexpressing OsAMT1-1 were produced by Agrobacterium-mediated transformation of two rice cultivars, Taipei 309 and Jarrah, with an OsAMT1-1 cDNA gene construct driven by the maize ubiquitin promoter. Transcript levels of OsAMT1-1 in both Taipei 309 and Jarrah transgenic lines correlated positively with transgene copy number. Shoot and root biomass of some transgenic lines decreased during seedling and early vegetative stage compared to the wild type, especially when grown under high (2 mm) ammonium nutrition. Transgenic plants, particularly those of cv. Jarrah recovered in the mid-vegetative stage under high ammonium nutrition. Roots of the transgenic plants showed increased ammonium uptake and ammonium content. We conclude that the decreased biomass of the transgenic lines at early stages of growth might be caused by the accumulation of ammonium in the roots owing to the inability of ammonium assimilation to match the greater ammonium uptake.

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Characterization of the Putative Transposase mRNA of Tag1, Which Is Ubiquitously Expressed in Arabidopsis and Can Be Induced by Agrobacterium-Mediated Transformation With dTag1 DNA

Genetics ◽

10.1093/genetics/149.2.693 ◽

1998 ◽

Vol 149 (2) ◽

pp. 693-701 ◽

Cited By ~ 3

Author(s):

Dong Liu ◽

Nigel M Crawford

Keyword(s):

Arabidopsis Thaliana ◽

Transposable Element ◽

Nuclear Localization ◽

Nuclear Localization Signal ◽

Transcript Levels ◽

Agrobacterium Mediated Transformation ◽

Transgenic Lines ◽

Localization Signal ◽

Transposase Mrna

Abstract Tag1 is an autonomous transposable element of Arabidopsis thaliana. Tag1 expression was examined in two ecotypes of Arabidopsis (Columbia and No-0) that were transformed with CaMV 35S-Tag1-GUS DNA. These ecotypes contain no endogenous Tag1 elements. A major 2.3-kb and several minor transcripts were detected in all major organs of the plants. The major transcript encoded a putative transposase of 84.2 kD with two nuclear localization signal sequences and a region conserved among transposases of the Ac or hAT family of elements. The abundance of Tag1 transcripts varied among transgenic lines and did not correlate with somatic excision frequency or germinal reversion rates, suggesting that factors other than transcript levels control Tag1 excision activity. In untransformed plants of the Landsberg ecotype, which contain two endogenous Tag1 elements, no Tag1 transcripts were detected. Agrobacterium-mediated transformation of these Landsberg plants with a defective 1.4-kb Tag1 element resulted in the appearance of full-length Tag1 transcripts from the endogenous elements. Transformation with control DNA containing no Tag1 sequences did not activate endogenous Tag1 expression. These results indicate that Agrobacterium-mediated transformation with dTag1 can activate the expression of Tag1.

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Hierarchical Action of Mulberry miR156 in the Vegetative Phase Transition

International Journal of Molecular Sciences ◽

10.3390/ijms22115550 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5550

Author(s):

Hongshun Li ◽

Yiwei Luo ◽

Bi Ma ◽

Jianqiong Hu ◽

Zhiyuan Lv ◽

...

Keyword(s):

Phase Transition ◽

Arabidopsis Thaliana ◽

Woody Plants ◽

Luciferase Reporter ◽

Vegetative Phase ◽

Promoter Sequences ◽

Over Expression ◽

Degradome Sequencing ◽

Pathway Expression ◽

Reporter Assays

The vegetative phase transition is a prerequisite for flowering in angiosperm plants. Mulberry miR156 has been confirmed to be a crucial factor in the vegetative phase transition in Arabidopsis thaliana. The over-expression of miR156 in transgenic Populus × canadensis dramatically prolongs the juvenile phase. Here, we find that the expression of mno-miR156 decreases with age in all tissues in mulberry, which led us to study the hierarchical action of miR156 in mulberry. Utilizing degradome sequencing and dual-luciferase reporter assays, nine MnSPLs were shown to be directly regulated by miR156. The results of yeast one-hybrid and dual-luciferase reporter assays also revealed that six MnSPLs could recognize the promoter sequences of mno-miR172 and activate its expression. Our results demonstrate that mno-miR156 performs its role by repressing MnSPL/mno-miR172 pathway expression in mulberry. This work uncovered a miR156/SPLs/miR172 regulation pathway in the development of mulberry and fills a gap in our knowledge about the molecular mechanism of vegetative phase transition in perennial woody plants.

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