Can biofuel crops alleviate tribal poverty in India's drylands?

The on-going climate change concerns have stimulated heavy interest in biofuels, and supporters of biofuels hail that they are considered naturally carbon-neutral. Critiques on the other hand cry that the large-scale production of biofuels can not only strain agricultural resources, but also threaten future food security. People who live in the drylands of India are often faced with challenges and constraints of poverty. Foremost among the challenges are the marginal environmental conditions for agriculture, often influenced by low and erratic rainfall, frequent droughts, poor soil condition, unreliable irrigation water supply, and rural migration to urban areas in search of work. In this paper, we have analyzed a case study of community lift irrigation practiced in India and its impact in boosting agricultural productivity and enhancing local food security. The lift-irrigation model practiced in the drylands of India to grow food crops can be adopted for the expansion of biofuel crops that has the potential to eradicate poverty among farming communities if appropriate sustainable development measures are carefully implemented.Biofuel India Agriculture Poverty Lift irrigation Drylands

Liraglutide Activates Glucagon-Like Peptide 1 Receptor to Attenuate Hyperglycemia through Endogenous Beta-Endorphin in Diabetic Rats

Liraglutide, an acylated analog of glucagon-like peptide 1 (GLP-1), could improve glycemic control in diabetes. Moreover, endogenous opioid peptides play a role in blood sugar regulation. Since GLP-1 receptors are also expressed in extra-pancreatic tissues, this study investigates the effect of liraglutide on endogenous opioid secretion in type 1-like diabetes. The endogenous opioid level was determined by enzyme-linked immunosorbent assay. The direct effect of liraglutide on endogenous opioid secretion was determined in the isolated adrenal medulla. Acute treatment with liraglutide dose-dependently attenuated hyperglycemia, and increased the plasma opioid neuropeptide, beta-endorphin (BER) levels in diabetic rats. These effects have been blocked by GLP-1 receptor antagonist, naloxone. Additionally, the effects of liraglutide were markedly reduced in adrenalectomized diabetic rats. In the isolated adrenal medulla, liraglutide induced BER secretion and increased the BER mRNA levels. Subcellular effects of liraglutide on the adrenal gland were further identified to mediate through the exchange proteins directly activated by cAMP, mainly using the pharmacological blockade. After repeatedly administering liraglutide, metabolic changes in diabetic rats were investigated, and genes associated with gluconeogenesis in the liver were downregulated. Naloxone pretreatment inhibited these effects of liraglutide, indicating the involvement of endogenous opioids. The present study indicated that liraglutide had an acute effect of reducing hyperglycemia by regulating endogenous opioid BER and modifying the glucose homeostasis

14-3-3θ is a Binding Partner of Rat Eag1 Potassium Channels

<div><p>The <em>ether-à-go-go</em> (Eag) potassium (K⁺) channel belongs to the superfamily of voltage-gated K⁺ channel. In mammals, the expression of Eag channels is neuron-specific but their neurophysiological role remains obscure. We have applied the yeast two-hybrid screening system to identify rat Eag1 (rEag1)-interacting proteins from a rat brain cDNA library. One of the clones we identified was 14-3-3θ, which belongs to a family of small acidic protein abundantly expressed in the brain. Data from <em>in vitro</em> yeast two-hybrid and GST pull-down assays suggested that the direct association with 14-3-3θ was mediated by both the N- and the C-termini of rEag1. Co-precipitation of the two proteins was confirmed in both heterologous HEK293T cells and native hippocampal neurons. Electrophysiological studies showed that over-expression of 14-3-3θ led to a sizable suppression of rEag1 K⁺ currents with no apparent alteration of the steady-state voltage dependence and gating kinetics. Furthermore, co-expression with 14-3-3θ failed to affect the total protein level, membrane trafficking, and single channel conductance of rEag1, implying that 14-3-3θ binding may render a fraction of the channel locked in a non-conducting state. Together these data suggest that 14-3-3θ is a binding partner of rEag1 and may modulate the functional expression of the K⁺ channel in neurons.</p> </div

Estimation of the single channel conductance of rEag1 channel under different co-expression paradigms.

<p>rEag1 K⁺ channels were co-expressed with either the control vector, difopein, or 14-3-3θ in HEK293 cells. <i>(</i><b><i>A</i></b><i>)</i> Comparison of the mean current density (pA/pF) at +40 mV: rEag1+vector, 111.2±9.5; rEag1+difopein, 126.9±13.2; rEag1+14-3-3θ, 76.8±5.8. The numbers in the parentheses refer to the number of cells analyzed, and the asterisk denotes significant difference from the rEag1+vector control (*, <i>t</i>-test: p<0.05). <i>(</i><b><i>B</i></b><i>)</i> Representative non-stationary fluctuation analysis of rEag1 K⁺ currents. (<i>Top row</i>) Whole cell current traces were evoked by 300-ms depolarizations from −90 mV to +40 mV, which were used to generate the ensemble mean (<i>second row</i>) and variance (<i>third row</i>). (<i>Bottom row</i>) The mean-variance plot (during the 300-ms test pulse, with the linear capacitative component eliminated)(<i>open circles</i>) was fit with a parabolic function (<i>solid curve</i>) to estimate the single channel current (0.9 pA). <i>(</i><b><i>C</i></b><i>)</i> Box plot presentation of the distribution of the estimated single channel conductance. Mean values (pS): rEag1+vector, 7.5±0.9; rEag1+difopein, 7.0±2.3; rEag1+14-3-3θ, 8.0±1.1. No significant difference was found among the three co-expression conditions (One-way ANOVA: p>0.05).</p

Localization of 14-3-3θ and rEag1 in synaptosomal and PSD fractions.

<p><i>(</i><b><i>A</i></b><i>)</i> Subcellular fractionation separated rat brains into multiple fractions: homogenate (H), soluble fraction (S1), crude membrane fraction (P2), synaptosomal fraction (SPM), and two postsynaptic density (PSD) preparations (PSD I: one Triton X-100 wash; PSD II: two Triton X-100 washes), all of which were subject to immunoblotting analyses with the indicated antibodies. 25 µg and 5 µg refer to the amount of total protein loaded in each lane. <i>(</i><b><i>B</i></b><i>)</i> Quantitative analyses of protein abundance in different subcellular fractions. Densitometric scans of immunoblots were obtained from three to five independent experiments. Data were presented as normalized values with respect to cognate protein expression levels in the homogenate (H) fraction.</p

Lack of effect of 14-3-3θ over-expression on the total and surface expression of rEag1 protein.

<p><i>(</i><b><i>A</i></b><i>)</i> Representative result of surface biotinylation experiments. Intact HEK293T cells were biontylinated on ice and thereafter solubilized. (<i>Surface</i>) Cell lysates were pulled down with streptavidin agarose beads, followed by immunoblotting with the anti-rEag1 antibody. (<i>Input</i>) Cell lysates were directly employed for immunoblotting analyses. Input represents 5% of the total protein used for streptavidin pull-down. Also shown at the bottom are the corresponding β-actin expression levels for each lane. The specificity of the biotinylation procedure was verified by the absence of β-actin bands in the surface fraction. <i>(</i><b><i>B</i></b><i>)</i> Quantification of total and surface expression of rEag1 in the absence or presence of 14-3-3θ over-expression. The total protein density (<i>top panel</i>) was determined as the ratio of input signal to the cognate β-actin signal. The surface expression efficiency (<i>bottom panel</i>) was expressed as the ratio of surface signal to the corresponding total protein density. The mean values were subsequently normalized with respect to that of vector control. Densitometric scans of immunoblots were obtained from three independent experiments.</p

Isoform specificity of 14-3-3 binding with rEag1 N- and C-termini.

<p><i>(</i><b><i>A</i></b><i>)</i> GST pull-down assay of cell lysates from HEK293T cells transfected with various myc-tagged 14-3-3 isoforms. (<i>Left panel</i>) Coomassie blue staining of the GST proteins. (<i>Right panel</i>) Immunoblotting of pull-down products with the anti-myc antibody. Input volume shown at the bottom corresponds to 5% of the total cell lysates for pull-down. <i>(</i><b><i>B</i></b><i>)</i> Quantification of the pull-down efficiency of different 14-3-3 isoforms. The protein band intensities of individual myc-14-3-3 isoforms affinity precipitated by GST-N207 or GST-C0 in (A) were divided by those of cognate total inputs, thereby minimizing the potential bias conferred by the variation in protein expression among different 14-3-3 isoforms. Densitometric scans of immunoblots were obtained from three independent experiments.</p

Endogenous expression of 14-3-3θ and rEag1 in neurons.

<p><i>(</i><b><i>A</i></b><i>)</i> Co-immunoprecipitation of 14-3-3θ and rEag1. Detergent solubilized proteins from the lysates of rat forebrain were immunoprecipitated (<i>IP</i>) with the anti-14-3-3θ (<i>upper panel</i>) or the anti-rEag1 antibody (<i>lower panel</i>), followed by immunoblotting (<i>WB</i>) analyses with the anti-14-3-3θ or the anti-rEag1 antibody. The non-immune mouse or rabbit IgG was used in parallel as negative control. Input volumes correspond to 5% of the total cell lysates used for immunoprecipitation. The arrowhead and arrow refers to the protein bands of 14-3-3θ and rEag1, respectively. <i>(</i><b><i>B</i></b><i>)</i> Immunofluorescence staining of rEag1 (<i>left panels</i>) and 14-3-3θ (<i>middle panels</i>) in cultured hippocampal neurons. The area highlighted in the white boxes is viewed under a higher magnification (<i>I, II</i>). Arrows label the sites of co-localization of 14-3-3θ and rEag1 (<i>right panels</i>), which displayed significant punctuate patterns over a wide region along the neurites. Scale bar, 25 µm. These co-immunoprecipitation and immunofluorescence data are representative of four to seven independent experiments.</p