p23h rhodopsin transgenic: Topics by WorldWideScience.org

Stochastic simulation of the transducin GTPase cycle.

Visual excitation is initiated by the absorption of a photon by the 11-cis retinal chromophore bound within the pigment called rhodopsin. We have used a variety of vibrational spectroscopies to obtain information about the vibrational nuclear dynamics that lead to this efficient photochemical isomerization. The cis-trans isomerization in rhodopsin is complete in only 200 fs. The extreme speed of this process, which is consistent with the {approximately}50 fs lifetime indicated by the spontaneous emission yield, suggests that the photochemistry involves non-stationary states or vibrational coherence. Recent studies have in fact observed vibrationally coherent oscillations of the ground state photoproduct called bathorhodopsin following impulsive excitation of the rhodopsin reactant. This conclusively demonstrates that the isomerization process in rhodopsin is vibrationally coherent. These observations ...

1995-12-31

Human anti-rhesus D IgG1 antibody produced in transgenic plants.

On rod disc membranes, single photoactivated rhodopsin (R*) molecules catalytically activate many copies of the G-protein (Gt), which in turn binds and activates the effector (phosphodiesterase). We...Full Text Available

1996-12-01

DEFF Research Database (Denmark)

Udgivelsesdato: 2002-Apr

2002-01-01

Expressional Characterization of Dehydroascorbate Reductase cDNA in Transgenic Potato Plants

KoreaScience (Korea)

Full Text Available

2008-01-01

Construction of the Transgenic Drosophila melanogaster Expressing a Human Megsin Gene.

KoreaScience (Korea)

Full Text Available

2007-05-01

Acquirement of transgenic rose plants from embryogenic calluses via Agrobacterium tumefaciens

KoreaScience (Korea)

Full Text Available

2010-12-01

Androgens and spermatogenesis: lessons from transgenic mouse models

Regulation of the expression of the apolipoprotein(a) gene : Evidence for a regulatory role of the 5' distal ACR enhancer in YAC transgenic mice

Transgenic mouse models have contributed considerably to our understanding of the cellular and molecular mechanisms by which androgens control spermatogenesis. Cell-selective ablation of the androgen...Full Text Available

2010-05-27

Axonal accumulation of synaptic markers in APP transgenic Drosophila depends on the NPTY motif and is paralleled by defects in synaptic plasticity.

No abstract prepared.

2003-01-30

DEFF Research Database (Denmark)

Udgivelsesdato: 2007-Feb

2007-01-01

Biological parameters of transgenic rabbits

British Library Electronic Table of Contents (United Kingdom)

The investigations were conducted at the Center of Biotechnology and Molecular Diagnostics of the All-Russian Animal Husbandry Research Institute, where a number of valuable transgenic animals (rabbits, sheep, and pigs) have been produced over the course of 20 years. The article presents the blood indices of control and transgenic rabbits with an integrated insulin gene.

2011-01-01

The CMV early enhancer/chicken beta actin (CAG) promoter can be used to drive transgene expression during the differentiation of murine embryonic stem cells into vascular progenitors.

DEFF Research Database (Denmark)

Udgivelsesdato: 2008-null

2008-01-01

Resistance pattern and antioxidant enzyme profiles of protoporphyrinogen oxidase (PROTOX) inhibitor-resistant transgenic rice

British Library Electronic Table of Contents (United Kingdom)

We quantified the resistance levels of transgenic rice plants, expressing Myxococcus xanthus protoporphyrinogen oxidase (PROTOX) in chloroplasts and mitochondria, to PROTOX inhibitors, acifluorfen, oxyfluorfen, carfentrazone-ethyl, and oxadiazon. We also determined whether active oxygen species-scavenging enzymes are involved in the resistance mechanism of transgenic rice. The transgenic rice line M4 was about >200-fold more resistant to oxyfluorfen than the wild-type (WT). M4 was also resistant to acifluorfen, carfentrazone-ethyl, and oxadiazon, but did not show multiple resistance to imazapyr and paraquat, which have different target sites. Acifluorfen, oxyfluorfen, carfentrazone-ethyl, and oxadiazon reduced the chlorophyll content in leaves of WT, but had minimal or no effect on M4. The...

2008-01-01

Agrobacterium-mediated transformation of cotton (Gossypium hirsutum L.) with a fungal phytase gene improves phosphorus acquisition

British Library Electronic Table of Contents (United Kingdom)

A phytase gene (phyA), isolated from Aspergillus ficuum (AF537344), was introduced into cotton (Gossypium hirsutum L.) by Agrobacterium-mediated transformation to increase the phosphorus (P) acquisition efficiency of cotton. Southern and Northern blot analyses showed that the phyA was successfully incorporated into the cotton genome and expressed in transgenic lines. After growing for 45?days with phytate (Po) as the only P source, the shoot and root dry weights of the transgenic plants all increased by nearly 2.0-fold relative to those of wild-type plants, but were similar to those of transgenic plants supplied with inorganic phosphorus. The phytase activities of root extracts prepared from transgenic plants were 2.4- to 3.6-fold higher than those from wild-type plants, and the extracellu...

2011-01-01

A Transposon and Transposase System for Human Application

Morphological, Histochemical, Immunohistochemical, and Ultrastructural Characterization of Tumors and Dysplastic and Non-Neoplastic Lesions Arising in BK Virus/tat Transgenic Mice

The stable introduction of therapeutic transgenes into human cells can be accomplished using viral and nonviral approaches. Transduction with clinical-grade recombinant viruses offers the potential...Full Text Available

2010-04-01

Cambial-Region-Specific Expression of the Agrobacterium iaa Genes in Transgenic Aspen Visualized by a Linked uidA Reporter Gene1

To study the role in AIDS pathogenesis of the human immunodeficiency virus type 1 (HIV-1) Tat protein, a transactivator of viral and cellular genes, we generated transgenic mice with a recombinant DNA...Full Text Available

1999-04-01

Channelrhodopsin-2 gene transduced into retinal ganglion cells restores functional vision in genetically blind rats

The level of indole-3-acetic acid (IAA) was locally modified in cambial tissues of transgenic aspen (Populus tremula L. × Populus tremuloides Michx.). We also...Full Text Available

2000-06-01

British Library Electronic Table of Contents (United Kingdom)

To test the hypothesis that transduction of the channelrhodopsin-2 (ChR2) gene, a microbial-type rhodopsin gene, into retinal ganglion cells of genetically blind rats will restore functional vision, we recorded visually evoked potentials and tested the experimental rats for the presence of optomotor responses. The N-terminal fragment of the ChR2 gene was fused to the fluorescent protein Venus and inserted into an adeno-associated virus to make AAV2-ChR2V. AAV2-ChR2V was injected intravitreally into the eyes of 6-month-old dystrophic RCS (rdy/rdy) rats. Visual function was evaluated six weeks after the injection by recording visually evoked potentials (VEPs) and testing optomotor responses. The expression of ChR2V in the retina was investigated histologically. We found that VEPs could not b...

2010-01-01

Prediction of the naturalisation potential and weediness risk of transgenic cotton in Australia

British Library Electronic Table of Contents (United Kingdom)

Climex climate-matching and inferential-modelling was used to examine the naturalisation potential of genetically modified and non-transgenic Upland Cotton (Gossypium hirsutum variety hirsutum) in Australia north of latitude 22degreeS. The Climate-Match (CM) function was used to identify locations in north-east Australia where climate matches (CM Index>0.7) the experimental sites of Eastick [Eastick, R., 2002. The Potential Weediness of Transgenic Cotton in Northern Australia. Northern Territory Department of Business, Industry and Resource Development Technical Bulletin No. 305 (Internet resource: http://cotton.pi.csiro.au/Assets/PDFFiles/TB3051.pdf)] in north-west Australia. Most of Australia north of 22degreeS had climate matching one or more of the sites of Eastick (2002), locations wh...

2007-01-01

Codon-modifications and an endoplasmic reticulum-targeting sequence additively enhance expression of an Aspergillus phytase gene in transgenic canola

British Library Electronic Table of Contents (United Kingdom)

Transgenic plants offer advantages for biomolecule production because plants can be grown on a large scale and the recombinant macromolecules can be easily harvested and extracted. We introduced an Aspergillus phytase gene into canola (Brassica napus) (line 9412 with low erucic acid and low glucosinolates) by Agrobacterium-mediated transformation. Phytase expression in transgenic plant was enhanced with a synthetic phytase gene according to the Brassica codon usage and an endoplasmic reticulum (ER) retention signal KDEL that confers an ER accumulation of the recombinant phytase. Secretion of the phytase to the extracellular fluid was also established by the use of the tobacco PR-S signal peptide. Phytase accumulation in mature seed accounted for 2.6% of the total soluble proteins. The enzy...

2006-01-01

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Wounding Nicotiana tabacum Leaves Causes a Decline in Endogenous Indole-3-Acetic Acid ¹

The protein encoded by the rolB plant oncogene hydrolyses indole glucosides.

We have previously observed that auxin can act as a repressor of the wound-inducible activation of a chimeric potato proteinase inhibitor II-CAT chimeric gene (pin2-CAT) in transgenic...Full Text Available

1991-07-01

The plant oncogene rolC is responsible for the release of cytokinins from glucoside conjugates.

The rolB gene of Agrobacterium rhizogenes, whose expression stimulates the formation of roots by transformed plant tissues and other growth alterations in transgenic plants, codes for a beta-glucosidase...Full Text Available

1991-11-01

Simultaneous expression of different transgenes in neurons and glia by combining in utero electroporation with the Tol2 transposon-mediated gene transfer system

The rolC gene of Agrobacterium rhizogenes, which drastically affects growth and development of transgenic plants, codes for a cytokinin-beta-glucosidase. Indeed, rolC protein expressed in Escherichia...Full Text Available

1991-10-01

Shielding of Sleeping Beauty DNA Transposon-delivered Transgene Cassettes by Heterologous Insulators in Early Embryonal Cells

In utero electroporation is widely used to study neuronal development and function by introducing plasmid DNA into neural progenitors during embryogenesis. This is an effective and...Full Text Available

2010-05-01

Role of Bv8 in neutrophil-dependent angiogenesis in a transgenic model of cancer progression

The Sleeping Beauty (SB) transposon system represents an important alternative to viral integrating vector systems but may, as its viral counterparts, be subject to transcriptional silencing. To investigate...Full Text Available

2009-01-01

Rhythmic expression of an egr-1 transgene in rats distinguishes two populations of photoreceptor cells in the retinal outer nuclear layer

The secreted Bv8 protein has been recently characterized as a regulator of myeloid cell mobilization and a neutrophil-derived mediator of tumor angiogenesis in several xenografts, but its role in tumor...Full Text Available

2008-02-19

Phosphorylation-dependent power output of transgenic flies: an integrated study.

PurposeNocturnal rhythms of gene expression in the retina are known to be both darkness- and circadian clock-dependent, but their role and cellular location are not well defined....Full Text Available

Neoplastic transformation of prostatic and urogenital epithelium by the polyoma virus middle T gene.

We examine how the structure and function of indirect flight muscle (IFM) and the entire flight system of Drosophila melanogaster are affected by phosphorylation of the myosin regulatory light chain...Full Text Available

1997-12-01

Lin28a transgenic mice manifest size and puberty phenotypes identified in human genetic association studies

Male transgenic mice expressing the polyomavirus middle T (PyV-MT) gene exhibited growth and developmental abnormalities in prostatic and other urogenital epithelium. Expression of PyV-MT was directed...Full Text Available

1996-10-01

Improvement of Aroma in Transgenic Potato As a Consequence of Impairing Tuber Browning

Recently, genome-wide association studies (GWAS) have linked the human LIN28B locus to height and timing of menarche [1-Full Text Available

2010-07-01

Heterogeneity of engrafted bone-lining cells after systemic and local transplantation

Sensory analysis studies are critical in the development of quality enhanced crops, and may be an important component in the public acceptance of genetically modified foods. It has recently been established...Full Text Available

Expression of a coriander desaturase results in petroselinic acid production in transgenic tobacco.

The outcome of various osteoprogenitor-cell transplantation protocols was assessed using Col1a1-GFP reporter transgenic mice. The model requires the recipient mice to undergo lethal total body irradiation...Full Text Available

2005-11-15

Efficient discovery of ASCL1 regulatory sequences through transgene pooling

Little is known about the metabolic origin of petroselinic acid (18:1 delta 6cis), the principal fatty acid of the seed oil of most Umbelliferae, Araliaceae, and Garryaceae species. To examine the possibility...Full Text Available

1992-12-01

De Novo Induction of Genetically Engineered Brain Tumors In Mice Using Plasmid DNA

Zebrafish transgenesis is a powerful and increasingly common strategy to assay vertebrate transcriptional regulatory control. Several challenges remain, however, to the broader application of...Full Text Available

2010-06-01

Cytokinin-Deficient Transgenic Arabidopsis Plants Show Multiple Developmental Alterations Indicating Opposite Functions of Cytokinins in the Regulation of Shoot and Root Meristem Activity

Spontaneous mouse models of cancer show promise to more accurately recapitulate human disease and predict clinical efficacy. Transgenic mice or viral vectors have been required to generate spontaneous...Full Text Available

2009-01-15

Cyst Formation in Kidney via B-Raf Signaling in the PKD2 Transgenic Mice*

Cytokinins are hormones that regulate cell division and development. As a result of a lack of specific mutants and biochemical tools, it has not been possible to study the consequences of cytokinin...Full Text Available

2003-11-01

Apolipoprotein E-Mimetics Inhibit Neurodegeneration and Restore Cognitive Functions in a Transgenic Drosophila Model of Alzheimer's Disease

The pathogenic mechanisms of human autosomal dominant polycystic kidney disease (ADPKD) have been well known to include the mutational inactivation of PKD2. Although haploinsufficiency...Full Text Available

2009-03-13

Animal models of human amyloidoses: Are transgenic mice worth the time and trouble?

BackgroundMutations of the amyloid precursor protein gene (APP) are found in familial forms of Alzheimer's disease (AD) and some lead to the elevated production...Full Text Available

A Humanin Derivative Reduces Amyloid Beta Accumulation and Ameliorates Memory Deficit in Triple Transgenic Mice

The amyloidoses are the prototype gain of toxic function protein misfolding diseases. As such, several naturally occurring animal models and their inducible variants provided some of the first...Full Text Available

2009-08-20

Improved salt tolerance and seed cotton yield in cotton (Gossypium hirsutum L.) by transformation with betA gene for glycinebetaine synthesis

Humanin (HN), a 24-residue peptide, was identified as a novel neuroprotective factor and shows anti-cell death activity against a wide spectrum of Alzheimer's disease (AD)-related cytotoxicities, including...Full Text Available

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British Library Electronic Table of Contents (United Kingdom)

Homozygous transgenic cotton (Gossypium hirsutum L.) plants that accumulated glycinebetaine (GB) in larger quantities were more tolerant to salt than wild-type (WT) plants. Four transgenic lines, namely 1, 3, 4, and 5, accumulated significantly higher levels of GB than WT plants did both before and after salt stress. At 175 and 275?mM NaCl, seeds of all the transgenic lines germinated earlier and recorded a higher final germination percentage, and the seedlings grew better, than those of the WT. Under salt stress, all the lines showed some characteristic features of salt tolerance, such as higher leaf relative water content (RWC), higher photosynthesis, better osmotic adjustment (OA), lower percentage of ion leakage, and lower peroxidation of the lipid membrane. Levels of endogenous GB in ...

2011-01-01

Copy number and orientation determine the susceptibility of a gene to silencing by nearby heterochromatin in Drosophila

Olfactory memory is impaired in a triple transgenic model of Alzheimer disease

The classical phenomenon of position-effect variegation (PEV) is the mosaic expression that occurs when a chromosomal rearrangements moves a euchromatic gene near heterochromatin. A striking feature of this phenomenon is that genes far away from the junction with heterochromatin can be affected, as if the heterochromatic state {open_quotes}spreads.{close_quotes} We have investigated classical PEV of a Drosophila brown transgene affected by a heterochromatic junction {approximately} 60 kb away. PEV was enhanced when the transgene was locally duplicated using P transposase. Successive rounds of P transpose mutagenesis and phenotypic selection produced a series of PEV alleles with differences in phenotype that depended on transgene copy number and orientation. As for other examples of classical PEV, nearby heterochromatin was required for gene silencing. Modifications of classical PEV by alterations at a single site are ...

1996-02-01

British Library Electronic Table of Contents (United Kingdom)

Olfactory memory dysfunctions were investigated in the triple-transgenic murine model of Alzheimer's disease (3x Tg-AD). In the social transmission of food preference test, 3x Tg-AD mice presented severe deficits in odor-based memory, without gross changes in general odor-ability. Ab and tau immunoreactivity was not observed in the primary processing regions for odor, the olfactory bulbs (OBs), whereas marked immunostaining was present in the piriform, entorhinal, and orbitofrontal cortex, as well as in the hippocampus. Our results suggest that the impairment in olfactory-based information processing might arise from degenerative mechanisms mostly affecting higher cortical regions and limbic areas, such as the hippocampus.

2011-01-01

Mammary gland tumor formation in transgenic mice overexpressing stromelysin-1

ALK, the Key Gene for Gelatinization Temperature, is a Modifier Gene for Gel Consistency in Rice

An intact basement membrane (BM) is essential for the proper function, differentiation and morphology of many epithelial cells. The disruption or loss of this BM occurs during normal development as well as in the disease state. To examine the importance of BM during mammary gland development in vivo, we generated transgenic mice that inappropriately express autoactivating isoforms of the matrix metalloproteinase stromelysin-1. The mammary glands from these mice are both functionally and morphologically altered throughout development. We have now documented a dramatic incidence of breast tumors in several independent lines of these mice. These data suggest that overexpression of stromelysin-1 and disruption of the BM may be a key step in the multi-step process of breast cancer.

1995-06-01

British Library Electronic Table of Contents (United Kingdom)

Abstract Gelatinization temperature (GT) is an important parameter in evaluating the cooking and eating quality of rice. Indeed, the phenotype, biochemistry and inheritance of GT have been widely studied in recent times. Previous map-based cloning revealed that GT was controlled by ALK gene, which encodes a putative soluble starch synthase II-3. Complementation vector and RNAi vector were constructed and transformed into Nipponbare mediated by Agrobacterium. Phenotypic and molecular analyses of transgenic lines provided direct evidence for ALK as a key gene for GT. Meanwhile, amylose content, gel consistency and pasting properties were also affected in transgenic lines. Two of four nonsynonymous single nucleotide polymorphisms in coding sequence of ALK were identified as essential for GT. ...

2011-01-01

A systematic RNAi screen reveals involvement of endocytic pathway in neuronal dysfunction in a-synuclein transgenic C. elegans

British Library Electronic Table of Contents (United Kingdom)

Mutations or multiplications in a-synuclein gene cause familial forms of Parkinson disease or dementia with Lewy bodies (LB), and the deposition of wild-type a-synuclein as LB occurs as a hallmark lesion of these disorders, collectively referred to as synucleinopathies, implicating a-synuclein in the pathogenesis of synucleinopathy. To identify modifier genes of a-synuclein-induced neurotoxicity, we conducted an RNAi screen in transgenic C. elegans (Tg worms) that overexpress human a-synuclein in a pan-neuronal manner. To enhance the RNAi effect in neurons, we crossed a-synuclein Tg worms with an RNAi-enhanced mutant eri-1 strain. We tested RNAi of 1673 genes related to nervous system or synaptic functions, and identified 10 genes that, upon knockdown, caused severe growth/motor abnormalit...

2008-01-01

Piperazine sulfonamide BACE1 inhibitors: Design, synthesis, and in vivo characterization

British Library Electronic Table of Contents (United Kingdom)

With collaboration between chemistry, X-ray crystallography, and molecular modeling, we designed and synthesized a series of novel piperazine sulfonamide BACE1 inhibitors. Iterative exploration of the non-prime side and S2prime sub-pocket of the enzyme culminated in identification of an analog that potently lowers peripheral Ab40 in transgenic mice with a single subcutaneous dose.

2010-01-01

High Levels of Tryptamine Accumulation in Transgenic Tobacco Expressing Tryptophan Decarboxylase ¹

Dietary effects on body composition, glucose metabolism, and longevity are modulated by skeletal muscle mitochondrial uncoupling in mice

A full-length complementary DNA clone encoding tryptophan decarboxylase (TDC; EC 4.1.1.28) from Catharanthus roseus (De Luca V, Marineau C, Brisson N [1989] Proc Natl Acad Sci USA 86:...Full Text Available

1990-11-01

Brazilian Free-tailed Bats (Tadarida brasiliensis) as Insect Pest Regulators in Transgenic and Conventional Cotton Crops

Little is known about how diet and energy metabolism interact in determination of lifespan under ad libitum feeding. From 12 weeks of age until death, male and female wild-type (WT) and transgenic (TG)...Full Text Available

2011-02-01

A non-toxic ligand for voxel-based MRI analysis of plaques in AD transgenic mice

During the past 12,000 years agricultural systems have transitioned from natural habitats to conventional agricultural regions, and recently to large areas of genetically- engineered (GE) croplands. This GE revolution occurred for cotton in a span of slightly more than a decade w...

Cotton plants expressing CYP6AE14 double-stranded RNA show enhanced resistance to bollworms

Amyloid plaques are a characteristic feature in Alzheimer’s disease (AD). A novel non-toxic contrast agent is presented, Gd-DTPA-K6Aβ1–30, which is homologous to Aβ,...Full Text Available

2008-06-01

British Library Electronic Table of Contents (United Kingdom)

RNA interference (RNAi) plays an important role in regulating gene expression in eukaryotes. Previously, we generated Arabidopsis and tobacco plants expressing double-stranded RNA (dsRNA) targeting a cotton bollworm (Helicoverpa armigera) P450 gene, CYP6AE14. Bollworms fed on transgenic dsCYP6AE14 plants showed suppressed CYP6AE14 expression and reduced growth on gossypol-containing diet (Mao et?al., in Nat Biotechnol 25: 1307?1313, 2007). Here we report generation and analysis of dsRNA-expressing cotton (Gossypium hirsutum) plants. Bollworm larvae reared on T2 plants of the ds6-3 line exhibited drastically retarded growth, and the transgenic plants were less damaged by bollworms than the control. Quantitative reverse-transcription polymerase chain reaction (RT-PCR) showed that the CYP6AE1...

2011-01-01

Biotechnology developments in the livestock sector in developing countries.

Aliskiren reduces vascular pathology in diabetic retinopathy and oxygen-induced retinopathy in the transgenic (mRen-2)27 rat

Global meat and milk consumption is exponentially increasing due to population growth, urbanization and changes in lifestyle in the developing world. This is an excellent opportunity for developing countries to improve the livestock sector by using technological advances. Biotechnology is one of the avenues for improved production in the "Livestock revolution". Biotechnology developments applied to livestock health, nutrition, breeding and reproduction are improving with a reasonable pace in developing countries. Simple bio-techniques such as artificial insemination have been well implemented in many parts of the developing world. However, advanced technologies including transgenic plant vaccines, marker assisted selection, solid state fermentation for the production of fibrolytic enzymes, transgenic fodders, embryo transfer and animal cloning are confined largely to research organizations. Some developing countries such as Taiwan, China and ...

2010-01-01

British Library Electronic Table of Contents (United Kingdom)

Aim/hypothesis We examined whether the renin inhibitor, aliskiren, provides similar or greater protection than ACE inhibition from non-proliferative diabetic retinopathy and from the proliferative neoangiogenesis of oxygen-induced retinopathy. Methods Transgenic (mRen-2)27 rats, which overexpress mouse renin and angiotensin in extra-renal tissues, were studied. For diabetic studies, non-diabetic, diabetic (streptozotocin, 55?mg/kg), diabetic + aliskiren (10?mg?kg?1?day?1, pump), or diabetic + lisinopril (10?mg?kg?1?day?1, drinking water) rats were evaluated over 16?weeks. For oxygen-induced retinopathy studies, rats were exposed to 80% oxygen (22?h/day) from postnatal days?0 to 11, and then room air from postnatal days?12 to 18. Aliskiren (10 or 30?mg?kg?1?day?1, pump) or lisinopril (10?mg...

2011-01-01

Phytoremediation of Ionic and Methyl Mercury P

Manganese-Induced NF-kB Activation and Nitrosative Stress Is Decreased by Estrogen in Juvenile Mice

Our long-term goal is to enable highly productive plant species to extract, resist, detoxify, and/or sequester toxic heavy metal pollutants as an environmentally friendly alternative to physical remediation methods. We have focused this phytoremediation research on soil and water-borne ionic and methylmercury. Mercury pollution is a serious world-wide problem affecting the health of human and wild-life populations. Methylmercury, produced by native bacteria at mercury-contaminated wetland sites, is a particularly serious problem due to its extreme toxicity and efficient biomagnification in the food chain. We engineered several plant species (e.g., Arabidopsis, tobacco, canola, yellow poplar, rice) to express the bacterial genes, merB and/or merA, under the control of plant regulatory sequences. These transgenic plants acquired remarkable properties for mercury remediation. (1) Transgenic plants expressing merB (organomercury lyase) extract ...

1999-06-01

British Library Electronic Table of Contents (United Kingdom)

Manganese toxicity can cause a neurodegenerative disorder affecting cortical and basal ganglia structures with a neurological presentation resembling features of Parkinson's disease. Children are more sensitive to Mn-induced neurological dysfunction than adults, and recent studies from our laboratory revealed a marked sensitivity of male juvenile mice to neuroinflammatory injury from Mn, relative to females. To determine the role of estrogen (E2) in mediating sex-dependent vulnerability to Mn-induced neurotoxicity, we exposed transgenic mice expressing an NF-kB-driven enhanced green fluorescent protein (EGFP) reporter construct (NF-kB-EGFP mice) to Mn, postulating that supplementing male mice with E2 during juvenile development would attenuate neuroinflammatory changes associated with glia...

2011-01-01

Intermediate-conductance calcium-activated potassium channels participate in neurovascular coupling

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE Controlling vascular tone involves K+ efflux through endothelial cell small- and intermediate-conductance calcium-activated potassium channels (KCa2.3 and KCa3.1, respectively). We investigated the expression of these channels in astrocytes and the possibility that, by a similar mechanism, they might contribute to neurovascular coupling. EXPERIMENTAL APPROACH Transgenic mice expressing enhanced green fluorescent protein (eGFP) in astrocytes were used to assess KCa2.3 and KCa3.1 expression by immunohistochemistry and RT-PCR. KCa currents in eGFP-positive astrocytes were determined in situ using whole-cell patch clamp electrophysiology. The contribution of KCa3.1 to neurovascular coupling was investigated in pharmacological experiments using electrical field stimulatio...

2011-01-01

Risk Assessment and Ecological Effects of Transgenic Bacillus thuringiensis Crops on Non-Target Organisms(F).

Development and evaluation of a conditionally lethal transgenic pink bollworm

Kong-Ming Wu (Corresponding author) The application of recombinant DNA technology has resulted in many insect-resistant varieties by genetic engineering (GE). Crops expressing Cry toxins derived from Bacillus thuringiensis (Bt) have been planted worldwide, and are an effective tool for pest control. However, one ecological concern regarding the potential effects of insect-resistant GE plants on non-target organisms (NTOs) has been continually debated. In the present study, we briefly summarize the data regarding the development and commercial use of transgenic Bt varieties, elaborate on the procedure and methods for assessing the non-target effects of insect-resistant GE plants, and synthetically analyze the related research results, mostly those published between 2005 and 2010. A mass of laboratory and field studies have shown that the currently available Bt crops have no direct detrimental effects on NTOs due to their narrow spectrum of activity, and Bt crops are ...

2011-07-01

International Nuclear Information System (INIS)

A new area-wide pest control strategy using the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), genetically transformed with a conditionally lethal gene, is under development. Conditional lethality of several transgenic pink bollworm strains was demonstrated in a series of laboratory rearing experiments. Pink bollworms were transformed with genetic constructs using the RIDL technology (Release of Insects with a Dominant Lethal gene) for development of an autocidal biological control system for possible supplement or replacement of radiation based sterile insect release. LA1124 is a lethal construct controlled by a tetracycline repressible transactivator protein (tTA), in which binding of tTA to its specific target sequence tetO drives production of more tTA. In the absence of tetracycline, this leads to lethality by high expression of tTA. When tetracycline is present, tTA does not bind tetO, and so the positive feedback cycle is not ...

2005-05-09

Rice RING protein OsBBI1 with E3 ligase activity confers broad-spectrum resistance against Magnaporthe oryzae by modifying the cell wall defence

British Library Electronic Table of Contents (United Kingdom)

Emerging evidence suggests that E3 ligases play critical roles in diverse biological processes, including innate immune responses in plants. However, the mechanism of the E3 ligase involvement in plant innate immunity is unclear. We report that a rice gene, OsBBI1, encoding a RING finger protein with E3 ligase activity, mediates broad-spectrum disease resistance. The expression of OsBBI1 was induced by rice blast fungus Magnaporthe oryzae, as well as chemical inducers, benzothiadiazole and salicylic acid. Biochemical analysis revealed that OsBBI1 protein possesses E3 ubiquitin ligase activity in vitro. Genetic analysis revealed that the loss of OsBBI1 function in a Tos17-insertion line increased susceptibility, while the overexpression of OsBBI1 in transgenic plants conferred enhanced resi...

2011-01-01

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Regulatory role of neuron-restrictive silencing factor in expression of TRPC1

International Nuclear Information System (INIS)

Neuron-restrictive silencer factor (NRSF) binds its consensus element to repress the transcription of various genes. The dominant-negative form (dnNRSF) has a hypertrophic effect on cardiogenesis through an unidentified mechanism. We examined the involvement of transient receptor potential (TRP) channel proteins, using transgenic mice overexpressing dnNRSF (dnNRSF mice). Electrophoretic mobility-shift assays revealed an interaction between NRSF and a neuron-restrictive silencer element-like sequence in intron 4 of TRPC1 genomic DNA. According to RT-PCR and Western analyses, TRPC1 was up-regulated in dnNRSF mouse heart. Transient overexpression of TRPC1 in HEK 293T cells increased the activity of the nuclear factor in activated T cells (NFAT) promoter and stimulated store-operated Ca"2"+ channel (SOCC)-mediated Ca"2"+ entry. Transfection of TRPC1 into primary cardiomyocytes increased NFAT activity, indicating a major role for TRPC1 in NFAT activation. Our findings ...

2006-12-22

Overexpression of a maize dehydrin gene, ZmDHN2b, in tobacco enhances tolerance to low temperature

British Library Electronic Table of Contents (United Kingdom)

Dehydrins, a subfamily of group 2 LEA proteins, are intrinsically unstructured plant proteins that accumulate in the late stages of seed development and in vegetative tissues subjected to water deficit, salinity, low temperature, or abscisic acid treatment. In this study, we isolated and characterized ZmDHN2b, a maize dehydrin gene. The genomic organization of the ZmDHN2b gene and its expression in maize seedlings were analyzed. To investigate the function of ZmDHN2b, we generated transgenic tobacco plants constitutively overexpressing ZmDHN2b. Ectopic expression of ZmDHN2b in tobacco accelerated seed germination and seedling growth at 15?C. Furthermore, ZmDHN2b-overexpressing lines had lower levels of cold-induced malondialdehyde and less electrolyte leakage than wild-type tobacco at 4?C....

2011-01-01

Development of a novel mouse tk{sup +/-} embryonic stem cell line for use in mutagenicity studies

Transcription regulation of the vegf gene by the BMP/Smad pathway in the angioblast of zebrafish embryos

A tk{sup +/-} mouse embryonic stem (ES) cell line, designated 1G2, has been created in which one allele of the thymidine kinase (tk) gene was inactivated by targeted homologous recombination. This line is an analog of the mouse lymphoma tk{sup +/-} L5178Y cell line, which is used widely to assess the mutagenicity of chemical agents. Treatment of 1G2 cells with the alkylating agent N-ethyl-N-nitrosourea (ENU) resulted in a dose-related increase in tribluorothymidine-resistant colonies. Mutant frequencies of 152 and 296 per 10{sup 6} cells were determined for 0.1 and 0.3 mg/ml doses of ENU, compared with a spontaneous mutant frequency of 15 per 10{sup 6} cells. The data indicate that tk{sup +/-} 1G2 ES cells may be useful for the creation of a transgenic mouse model for assessing in vivo mutation using an endogenous autosomal gene. 45 refs., 2 figs., 1 tab.

1996-12-31

The enhanced genomic instability was induced by alpha particle and low-energy ion irradiation in somatic cells of Arabidopsis thaliana

Vascular endothelial growth factor (VEGF) is a mitogen that is critically involved in vasculogenesis, angiogenesis, and hematopoiesis. However, what and how transcription factors participate in the regulation of vegf gene expression are not fully understood. Here we report the cloning and sequencing of the zebrafish vegf promoter which revealed that the promoter contains a number of bone morphogenetic protein (BMP)-activated Smad binding elements (SBE), implicating Smad1 and Smad5 in the regulation of BMP-induced expression of vegf. Electrophoretic mobility shift assays of adding recombinant Smad proteins to the SBE-containing DNA oligonucleotides that represent portions of zebrafish vegf promoter resulted in mobility shift of the oligonucleotides. These changes demonstrate potential interactions between Smad1/5 and the vegf promoter. Reporter activity assays using the wild-type or SBE-deleted vegf promoters to drive the luciferase reporter gene expression revealed that Smad1 ...

2005-04-01

International Nuclear Information System (INIS)

Although low-energy ion radiation has been proven to have a wide range of biological effects and led to fruitful achievements as a new mutagenic source for genetic modification, there still exist some disputes about its mutagenic mechanisms because of its short-penetrating property. In present research, Arabidopsis thaliana transgenic for GUS recombination substrate was used to evaluate the genomic instability induced by irradiations of alpha particle (3.3MeV) and Low-energy-Argon ion (30 KeV). A pronounced effects of alpha particle irradiation to Arabidopsis thaliana seedlings and Argon ion irradiation to seeds on the somatic homologous recombination frequency (sHRF) were reported. The sHRFs increased 1.88-fold and 2.42-fold, respectively, which indicated that the short-penetrating radiation could effectively induce the plant genomic instability in either dry seeds or seedlings with active metabolism. The local alpha particle irradiation of root was performed. ...

2008-08-12

Computational identification of developmental enhancers:conservation and function of transcription factor binding-site clustersin drosophila melanogaster and drosophila psedoobscura