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71.
Plastid-expressed betaine aldehyde dehydrogenase gene in carrot cultured cells, roots, and leaves confers enhanced salt tolerance 总被引:42,自引:0,他引:42
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Salinity is one of the major factors that limits geographical distribution of plants and adversely affects crop productivity and quality. We report here high-level expression of betaine aldehyde dehydrogenase (BADH) in cultured cells, roots, and leaves of carrot (Daucus carota) via plastid genetic engineering. Homoplasmic transgenic plants exhibiting high levels of salt tolerance were regenerated from bombarded cell cultures via somatic embryogenesis. Transformation efficiency of carrot somatic embryos was very high, with one transgenic event per approximately seven bombarded plates under optimal conditions. In vitro transgenic carrot cells transformed with the badh transgene were visually green in color when compared to untransformed carrot cells, and this offered a visual selection for transgenic lines. BADH enzyme activity was enhanced 8-fold in transgenic carrot cell cultures, grew 7-fold more, and accumulated 50- to 54-fold more betaine (93-101 micromol g(-1) dry weight of beta-Ala betaine and Gly betaine) than untransformed cells grown in liquid medium containing 100 mm NaCl. Transgenic carrot plants expressing BADH grew in the presence of high concentrations of NaCl (up to 400 mm), the highest level of salt tolerance reported so far among genetically modified crop plants. BADH expression was 74.8% in non-green edible parts (carrots) containing chromoplasts, and 53% in proplastids of cultured cells when compared to chloroplasts (100%) in leaves. Demonstration of plastid transformation via somatic embryogenesis utilizing non-green tissues as recipients of foreign DNA for the first time overcomes two of the major obstacles in extending this technology to important crop plants. 相似文献
72.
Stable transformation of the cotton plastid genome and maternal inheritance of transgenes 总被引:23,自引:0,他引:23
Chloroplast genetic engineering overcomes concerns of gene containment, low levels of transgene expression, gene silencing, positional and pleiotropic effects or presence of vector sequences in transformed genomes. Several therapeutic proteins and agronomic traits have been highly expressed via the tobacco chloroplast genome but extending this concept to important crops has been a major challenge; lack of 100 homologous species-specific chloroplast transformation vectors containing suitable selectable markers, ability to regulate transgene expression in developing plastids and inadequate tissue culture systems via somatic embryogenesis are major challenges. We employed a Double Gene/Single Selection (DGSS) plastid transformation vector that harbors two selectable marker genes (aphA-6 and nptII) to detoxify the same antibiotic by two enzymes, irrespective of the type of tissues or plastids; by combining this with an efficient regeneration system via somatic embryogenesis, cotton plastid transformation was achieved for the first time. The DGSS transformation vector is at least 8-fold (1 event/2.4 bombarded plates) more efficient than Single Gene/Single Selection (SGSS) vector (aphA-6; 1 event per 20 bombarded plates). Chloroplast transgenic lines were fertile, flowered and set seeds similar to untransformed plants. Transgenes stably integrated into the cotton chloroplast genome were maternally inherited and were not transmitted via pollen when out-crossed with untransformed female plants. Cotton is one of the most important genetically modified crops ($ 120 billion US annual economy). Successful transformation of the chloroplast genome should address concerns about transgene escape, insects developing resistance, inadequate insect control and promote public acceptance of genetically modified cotton. 相似文献
73.
Income inequality and depression: a systematic review and meta‐analysis of the association and a scoping review of mechanisms
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Vikram Patel Jonathan K. Burns Monisha Dhingra Leslie Tarver Brandon A. Kohrt Crick Lund 《World psychiatry》2018,17(1):76-89
Most countries have witnessed a dramatic increase of income inequality in the past three decades. This paper addresses the question of whether income inequality is associated with the population prevalence of depression and, if so, the potential mechanisms and pathways which may explain this association. Our systematic review included 26 studies, mostly from high‐income countries. Nearly two‐thirds of all studies and five out of six longitudinal studies reported a statistically significant positive relationship between income inequality and risk of depression; only one study reported a statistically significant negative relationship. Twelve studies were included in a meta‐analysis with dichotomized inequality groupings. The pooled risk ratio was 1.19 (95% CI: 1.07‐1.31), demonstrating greater risk of depression in populations with higher income inequality relative to populations with lower inequality. Multiple studies reported subgroup effects, including greater impacts of income inequality among women and low‐income populations. We propose an ecological framework, with mechanisms operating at the national level (the neo‐material hypothesis), neighbourhood level (the social capital and the social comparison hypotheses) and individual level (psychological stress and social defeat hypotheses) to explain this association. We conclude that policy makers should actively promote actions to reduce income inequality, such as progressive taxation policies and a basic universal income. Mental health professionals should champion such policies, as well as promote the delivery of interventions which target the pathways and proximal determinants, such as building life skills in adolescents and provision of psychological therapies and packages of care with demonstrated effectiveness for settings of poverty and high income inequality. 相似文献
74.
Madepalli K. Lakshmana B. S. Shankaranarayana Rao Narender K. Dhingra R. Ravikumar Govindaiah S. Sudha B. L. Meti T. R. Raju 《Neurochemical research》1998,23(8):1031-1037
The role of monoamine oxidase (MAO) type A and B on the metabolism of dopamine (DA) in discrete regions of the monkey brain was studied. Monkeys were administered (–)-deprenyl (0.25 mg/kg) or clorgyline (1.0 mg/kg) or deprenyl and clorgyline together by intramuscular injections for 8 days. Levels of DA and its metabolites, dihydroxy phenylacetic acid (DOPAC) and homovanillic acid (HVA) were estimated in frontal cortex (FC), motor cortex (MC), occipital cortex (OC), entorhinal cortex (EC), hippocampus (HI), hypothalamus (HY), caudate nucleus (CN), globus pallidus (GP) and substantia nigra (SN). (–)-Deprenyl administration significantly increased DA levels in FC, HY, CN, GP and SN (39–87%). This was accompanied by a reduction in the levels of DOPAC (37–66%) and HVA (27–79%). Clorgyline administration resulted in MAO-A inhibition by more than 87% but failed to increase DA levels in any of the brain regions studied. Combined treatment of (–)-deprenyl and clorgyline inhibited both types of MAO by more than 90% and DA levels were increased (57–245%) in all brain regions studied with a corresponding decrease in the DOPAC (49–83%) and HVA (54–88%) levels. Our results suggest that DA is metabolized preferentially, if not exclusively by MAO-B in some regions of the monkey brain. 相似文献
75.
Vikram Jeet Singh Dhingra Ashish Kumar Amit Mittal Samita Gupta Rikki Singal Bir Singh Chetan Dua 《Indian journal of human genetics》2013,19(4):469-471
Presence of one or more digit is called as polydactyly and may manifest singly or with other genetic disorders. The frequency of polydactyly varies widely among populations. It can occur as an isolated condition or as a feature of a congenital condition. Polydactyly is a rare condition, but still rare is in form of triple great toes. We describe a case in a 4-year-old child diagnosed as triphalangism foot with no other obvious visible anomaly. Osteoplasty-combined surgery, which was ideal for anatomical reconstruction. In a 16-month follow-up period child recovered very well. 相似文献
76.
Selenium deficiency has been associated with hypercholesterolemia. Present study was aimed to determine the effect of selenium
(Se) deficiency on LDL receptor (LDL-R) activity as well as mRNA expression during experimental hypercholesterolemia in SD
male rats. Animals were fed Se adequate (0.2 ppm) and deficient (0.02 ppm) control diet as well as high cholesterol (2%) diet
(HCD) for 1 and 2 months. LDL-R activity was measured in vivo by injecting radiolabeled LDL to rats and percent decrease in cpm with time was taken as a measure of LDL clearance and in
turn LDL-R activity. LDL-R mRNA expression was studied by RT-PCR. LDL-R activity and mRNA expression decreased significantly
on HCD feeding in both Se deficient and adequate diet fed rats after 2 months. In Se deficiency receptor activity and mRNA
expression decreased significantly. After 2 months LDL-R activity and expression decreased in both the Se deficient groups
and in Se adequate HCD fed group in comparison to 1 month data. But after 4 month there was no significant difference observed
in LDL-R activity and mRNA expression in selenium deficiency as well as on HCD feeding. So the present results demonstrate
that Se deficiency act synergistically with hypercholesterolemia to downregulate LDL-R activity as well as mRNA expression. 相似文献
77.
Summary Translational genomics is defined as the application of molecular-genetic principles derived from model systems to species
of experimental or economic interest. The past 20 years of research in plant model systems such as Arabidopsis thaliana have relinquished vast amounts of information regarding gene function, the integration of genetic components into pathways,
and the interrelationships between pathways to control form and function in plants and plant-products alike. At present, the
challenge is to relate these paradigms to other species of economic or scientific interest. Apart from being an important
and valuable crop, strawberry (Fragaria spp.) is a member of the Rosaceae, a plant family containing fruit, nut, ornamental and wood-bearing species. Strawberry is unique within the Rosaceae in that it is a rapidly growing herbaceous perennial with a small genome and the ability to thrive in a laboratory setting.
Strawberry species may also be transformed and regenerated in a time scale of weeks or months instead of years. For these
reasons, strawberry has been recognized as the translational genomics model for the Rosaceae family. This review summarizes and synthesizes the technical reports of strawberry regeneration and transformation, consolidating
the large body of information regarding genetic modification of this important genus. 相似文献
78.
Sunil Sazawal Usha Dhingra Pratibha Dhingra Girish Hiremath Archana Sarkar Arup Dutta Venugopal P. Menon Robert E. Black 《PloS one》2010,5(8)
Background
Multiple micronutrient deficiencies are highly prevalent among preschool children and often lead to anemia and growth faltering. Given the limited success of supplementation and health education programs, fortification of foods could be a viable and sustainable option. We report results from a community based double-masked, randomized trial among children 1–4 years evaluating the effects of micronutrients (especially of zinc and iron) delivered through fortified milk on growth, anemia and iron status markers as part of a four group study design, running two studies simultaneously.Methods and Findings
Enrolled children (n = 633) were randomly allocated to receive either micronutrients fortified milk (MN = 316) or control milk (Co = 317). Intervention of MN milk provided additional 7.8 mg zinc, 9.6 mg iron, 4.2 µg selenium, 0.27 mg copper, 156 µg vitamin A, 40.2 mg vitamin C, and 7.5 mg vitamin E per day (three serves) for one year. Anthropometry was recorded at baseline, mid- and end-study. Hematological parameters were estimated at baseline and end-study. Both groups were comparable at baseline. Compliance was over 85% and did not vary between groups. Compared to children consuming Co milk, children consuming MN milk showed significant improvement in weight gain (difference of mean: 0.21 kg/year; 95% confidence interval [CI] 0.12 to 0.31, p<0.001) and height gain (difference of mean: 0.51 cm/year; 95% CI 0.27 to 0.75, p<0.001). Mean hemoglobin (Hb) (difference of 13.6 g/L; 95% CI 11.1 to 16.0, p<0.001) and serum ferritin levels (difference of 7.9 µg/L; 95% CI 5.4 to 10.5, p<0.001) also improved. Children in MN group had 88% (odds ratio = 0.12, 95% CI 0.08 to 0.20, p<0.001) lower risk of iron deficiency anemia.Conclusions/Significance
Milk provides an acceptable and effective vehicle for delivery of specific micronutrients, especially zinc and iron. Micronutrient bundle improved growth and iron status and reduced anemia in children 1–4 years old.Trial Registration
ClinicalTrials.gov NCT00255385相似文献79.
Tyler Alioto Konstantinos G. Alexiou Amlie Bardil Fabio Barteri Raúl Castanera Fernando Cruz Amit Dhingra Henri Duval ngel Fernndez i Martí Leonor Frias Beatriz Galn Jos L. García Werner Howad Jssica Gmez‐Garrido Marta Gut Irene Julca Jordi Morata Pere Puigdomnech Paolo Ribeca María J. Rubio Cabetas Anna Vlasova Michelle Wirthensohn Jordi Garcia‐Mas Toni Gabaldn Josep M. Casacuberta Pere Arús 《The Plant journal : for cell and molecular biology》2020,101(2):455-472
80.
Ramirez-Torres Fabiola Ghogare Rishikesh Stowe Evan Cerdá-Bennasser Pedro Lobato-Gómez Maria Williamson-Benavides Bruce A Giron-Calva Patricia Sarai Hewitt Seanna Christou Paul Dhingra Amit 《Transgenic research》2021,30(4):499-528
Transgenic Research - The advent of genome editing has opened new avenues for targeted trait enhancement in fruit, ornamental, industrial, and all specialty crops. In particular, CRISPR-based... 相似文献