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Leaf blight caused by Alternariaster helianthi (Hansf.) Tubaki and Nishihara is one of the important diseases of sunflower that causes considerable yield loss. Resistance against leaf blight in the germplasm, parental lines and released sunflower cultivars is rather limited. Hence, screening of sunflower accessions comprised interspecific derivatives, core germplasm, pre-breeding lines, exotic lines and wild Helianthus species was carried out under natural field conditions over five years viz ., 2003 to 2009. Sunflower lines which showed resistance under field conditions were further confirmed under controlled conditions by artificial inoculation with A . helianthi . Among interspecific crosses evaluated, pre-breeding lines derived from crosses of cultivated sunflower with wild H . annuus (ANN-SF) followed by trispecific crosses of cultivated sunflower with H . argophyllus , wild H . annuus (ARG-ANN-SF) and cultivated sunflower with H . argophyllus (ARG-SF) showed less leaf blight disease under field conditions. The disease severity was greater during 2004–05, 2006–07, 2007–08 and 2009–10 which was favoured by high rainfall, many rainy days and high relative humidity. Six sunflower accessions showed less leaf blight severity. Of three A . helianthi isolates tested, Ah -112 was found to be highly aggressive causing more than 30% leaf blight severity on all tested cultivars. Among different wild Helianthus species tested against leaf blight by detached leaf and whole plant assay techniques, H . tuberosus Acc 03, 1705, 08, 07, 15, 2729, H . maximiliani Acc 007 and H . strumosus Acc 15 recorded <20% leaf blight severity in the whole plant assay method indicating some resistance. Appropriate strategies are being devised to utilize the interspecific accessions and wild Helianthus species identified to be moderately resistant to Alternariaster leaf blight in the sunflower breeding programmes. [ABSTRACT FROM AUTHOR]

Eukaryotic elongation factor-2 kinase (eEF2K) relays growth and stress signals to protein synthesis through phosphorylation and inactivation of eukaryotic elongation factor 2 (eEF2). 1-Benzyl-3-cetyl-2-methylimidazolium iodide (NH125) is a widely accepted inhibitor of mammalian eEF2K and an efficacious antiproliferation agent against different cancer cells. It implied that eEF2K could be an efficacious anticancer target. However, eEF2K siRNA was ineffective against cancer cells including those sensitive to NH125. To test if pharmacological intervention differs from siRNA interference, we identified a highly selective small molecule eEF2K inhibitor A-484954. Like siRNA, A-484954 had little effect on cancer cell growth. We carefully examined the effect of NH125 and A-484954 on phosphorylation of eEF2, the known cellular substrate of eEF2K. Surprisingly, NH125 increased eEF2 phosphorylation, whereas A-484954 inhibited the phosphorylation as expected for an eEF2K inhibitor. Both A-484954 and eEF2K siRNA inhibited eEF2K and reduced eEF2 phosphorylation with little effect on cancer cell growth. These data demonstrated clearly that the anticancer activity of NH125 was more correlated with induction of eEF2 phosphorylation than inhibition of eEF2K. Actually, induction of eEF2 phosphorylation was reported to correlate with inhibition of cancer cell growth. We compared several known inducers of eEF2 phosphorylation including AMPK activators and an mTOR inhibitor, Interestingly, stronger induction of eEF2 phosphorylation correlated with more effective growth inhibition. We also explored signal transduction pathways leading to NH125-induced eEF2 phosphorylation. Preliminary data suggested that NH 125-induced eEF2 phosphorylation was likely mediated through multiple pathways. These observations identified an opportunity for a new multipathway approach to anticancer therapies. [ABSTRACT FROM AUTHOR]

Abstract: Thirty four Jatropha germplasm accessions, selected based on unique phenotypic traits from 180 accessions collected from diverse geographical regions were subjected to field evaluation and molecular analysis. The field evaluation using eight quantitative traits showed significant variation among the germplasm. The molecular analysis using 56 RAPD and 40 ISSR primers resulted in 7 and 8 clusters, respectively. The accession IC541633 from Bastar (Chattisgarh) emerged as the most diverse accession. An attempt has been made to correlate the clustering based on molecular data with the quantitative traits. There was partial correlation between the quantitative traits and molecular data. Interestingly, the diverse accessions according to molecular diversity were characterized by unique phenotypes. Time of flowering, inflorescence type and number, leaf colour and texture were the traits contributing to variation. These traits may be used in identification of diverse accessions during germplasm exploration surveys or short listing of accessions for crossing in Jatropha improvement programmes. [Copyright &y& Elsevier]

Abstract: Fragile X syndrome (FRAXA) is one of the most common forms of mental retardation. It is caused by the expansion of cytosine-guanine-guanine (CGG) repeats in the 5′ untranslated region of the fragile X mental retardation 1 (FMR1) gene, located at Xq27.3. The number of CGG repeats in the FMR1 gene occurs in four distinct ranges: 2–50 (normal), 50–60 (gray zone), 60–200 (premutation), and > 200 (full mutation). When the number of CGG repeats exceeds 200, the gene becomes hypermethylated and transcriptionally silenced, which results in the loss of FMR protein and causes FRAXA. The key clinical features of FRAXA are mental retardation, macro-orchidism, long face, prominent jaw, connective tissue abnormalities, and behavioral problems. A modified 15-item checklist was used to assess the clinical features in 337 individuals (316 males and 21 females) who have mental retardation of unknown etiology. These patients were in institutions. Molecular diagnosis was performed using polymerase chain reaction and Southern blot analysis and revealed that 14 males were positive for FRAXA. Studies of the families of the affected males revealed an additional 11 affected males and 20 carrier females. Retrospective analysis of clinical features was performed in a total of 327 males and 41 females. Six clinical features were statistically significant in FRAXA individuals when compared to non-FRAXA individuals. These features were hyperactivity (p <0.05), poor eye contact (p <0.001), hyper extensibility of joints (p <0.001), large ears (p <0.001), macro-orchidism (p <0.001), and a family history of mental retardation (p <0.001). When a total score of 5 out of 15 was used as the threshold clinical score, 73.18% of the patients with total scores<5 could be eliminated as FRAXA-negative patients, thereby improving the reliability of FRAXA testing using the clinical checklist. [Copyright &y& Elsevier]

Abstract: Castor and Jatropha belong to the Euphorbiaceae family. This review highlights the role of biotechnological tools in the genetic improvement of castor and jatropha. Castor is monotypic and breeding programmes have mostly relied on the variability available in the primary gene pool. The major constraints limiting profitable cultivation are: vulnerability to insect pests and diseases, and the press cake is toxic which restrict its use as cattle feed. Conventional breeding techniques have limited scope in improvement of resistance to biotic stresses and in quality improvement owing to low genetic variability for these traits. Genetic diversity was assessed using protein based markers while use of molecular markers is at infancy. In vitro studies in castor have been successful in shoot proliferation from meristematic explants, but not callus-mediated regeneration. Genetic transformation experiments have been initiated for development of insect resistant and ricin-free transgenics with very low transformation frequency. In tropical and subtropical countries jatropha is viewed as a potential biofuel crop. The limitations in available germplasm include; lack of knowledge of the genetic base, poor yields, low genetic diversity and vulnerability to a wide array of insects and diseases. Great scope exists for genetic improvement through conventional methods, induced mutations, interspecific hybridization and genetic transformation. Reliable and highly efficient tissue culture protocols for direct and callus-mediated shoot regeneration and somatic embryogenesis are established for jatropha which indicates potential for widening the genetic base through biotechnological tools. Assessment of genetic diversity using molecular markers disclosed low interaccessional variability in local Jatropha curcas germplasm. The current status and future prospects of in vitro regeneration, genetic transformation and the role of molecular tools in the genetic enhancement of the two-oilseed crops are discussed. [Copyright &y& Elsevier]

Summary: Iron acquisition is essential for Mycobacterium tuberculosis (Mtb) virulence. Understanding the molecular mechanisms used by Mtb to scavenge iron during infection might reveal new targets for antimicrobial development. Rv2895c, a homolog of ViuB from Vibrio cholerae has been postulated to be involved in iron-siderophore uptake and utilization in Mtb. This study examines the requirement of Rv2895c for adaptation of Mtb to iron limitation. We show that Rv2895c is dispensable for normal replication of Mtb in iron deficient conditions and in human macrophages. Thus, contrary to the predictions of sequence analysis and in-vitro studies the genetic evidence indicates that in normal conditions Rv2895c is not required for iron acquisition in Mtb. [ABSTRACT FROM AUTHOR]

In drug discovery, during the lead optimization and candidate characterization stages, novel small molecules are frequently evaluated in a battery of in vitro pharmacology assays to identify potential unintended, off-target interactions with various receptors, transporters, ion channels, and enzymes, including kinases. Furthermore, these screening panels may also provide utility at later stages of development to provide a mechanistic understanding of unexpected safety findings. Here, we present a compendium of the most likely functional and pathological outcomes associated with interaction(s) to a panel of 95 kinases based on an extensive curation of the scientific literature. This panel of kinases was designed by AbbVie based on safety-related data extracted from the literature, as well as from over 20 years of institutional knowledge generated from discovery efforts. For each kinase, the scientific literature was reviewed using online databases and the most often reported functional and pathological effects were summarized. This work should serve as a practical guide for small molecule drug discovery scientists and clinical investigators to predict and/or interpret adverse effects related to pharmacological interactions with these kinases. [ABSTRACT FROM AUTHOR]

Rare sequence variants in the microglial cell surface receptor TREM2 have been shown to increase the risk for Alzheimer's disease (AD). Disease-linked TREM2 mutations seem to confer a partial loss of function, and increasing TREM2 cell surface expression and thereby its function(s) might have therapeutic benefit in AD. However, druggable targets that could modulate microglial TREM2 surface expression are not known. To identify such targets, we conducted a screen of small molecule compounds with known pharmacology using human myeloid cells, searching for those that enhance TREM2 protein at the cell surface. Inhibitors of the kinases MEK1/2 displayed the strongest and most consistent increases in cell surface TREM2 protein, identifying a previously unreported pathway for TREM2 regulation. Unexpectedly, inhibitors of the downstream effector ERK kinases did not have the same effect, suggesting that noncanonical MEK signaling regulates TREM2 trafficking. In addition, siRNA knockdown experiments confirmed that decreased MEK1 and MEK2 were required for this recruitment. In iPSC-derived microglia, MEK inhibition increased cell surface TREM2 only modestly, so various cytokines were used to alter iPSC microglia phenotype, making cells more sensitive to MEK inhibitor-induced TREM2 recruitment. Of those tested, only IFN-gamma priming prior to MEK inhibitor treatment resulted in greater TREM2 recruitment. These data identify the first known mechanisms for increasing surface TREM2 protein and TREM2-regulated function in human myeloid cells and are the first to show a role for MEK1/MEK2 signaling in TREM2 activity. [ABSTRACT FROM AUTHOR]

NAMPT expression is elevated in many cancers, making this protein a potential target for anticancer therapy. We have carried out both NMR based and TR-FRET based fragment screens against human NAMPT and identified six novel binders with a range of potencies. Co-crystal structures were obtained for two of the fragments bound to NAMPT while for the other four fragments force-field driven docking was employed to generate a bound pose. Based on structural insights arising from comparison of the bound fragment poses to that of bound FK866 we were able to synthetically elaborate one of the fragments into a potent NAMPT inhibitor. [ABSTRACT FROM AUTHOR]

Degradation of podocyte structural integrity and function are hallmarks of proteinuric chronic kidney disease. In vivo, injury of podocytes manifests itself in the form of disruption of foot process morphology and associated cytoskeletal architecture, de-differentiation, and loss of adhesion to the glomerular basement membrane. Given the critical role played by this highly specialized cell type in maintaining glomerular filtration, there is a need for improved physiologically relevant cellular models that enable detection of disease-relevant indicators of podocyte perturbation. We have addressed this need by evaluating a subclone of conditionally immortalized human podocytes through quantitative benchmarking against freshly isolated primary human podocytes. Benchmarking was performed by measuring key phenotypic parameters, expression of podocyte specific proteins and multiparametric responses to stressors that model different aspects of podocyte perturbation. We subsequently employed the subcloned cells to profile the protective activity of structurally distinct adenosine kinase inhibitors. Our results support the translatability of our cellular model and set the stage for broader screening of renoprotective compounds with a view to eventually treat proteinuric kidney disease. [ABSTRACT FROM AUTHOR]

Modification of the primary anchor positions of antigenic peptides to improve binding to major histocompatibility complex (MHC) proteins is a commonly used strategy for engineering peptide-based vaccine candidates. However, such peptide modifications do not always improve antigenicity, complicating efforts to design effective vaccines for cancer and infectious disease. Here we investigated the MART-127-35 tumor antigen, for which anchor modification (replacement of the position two alanine with leucine) dramatically reduces or ablates antigenicity with a wide range of T cell clones despite significantly improving peptide binding to MHC. We found that anchor modification in the MART-127-35 antigen enhances the flexibility of both the peptide and the HLA-A*0201 molecule. Although the resulting entropic effects contribute to the improved binding of the peptide to MHC, they also negatively impact T cell receptor binding to the peptide·MHC complex. These results help explain how the "anchor-fixing" strategy fails to improve antigenicity in this case, and more generally, may be relevant for understanding the high specificity characteristic of the T cell repertoire. In addition to impacting vaccine design, modulation of peptide and MHC flexibility through changes to antigenic peptides may present an evolutionary strategy for the escape of pathogens from immune destruction. [ABSTRACT FROM AUTHOR]

Abstract: Jatropha curcas has gained popularity as a potential biofuel crop but the major constraint for improvement of the crop for yield and seed quality traits is the narrow genetic base of the germplasm. Genetic background of 72 J. curcas accessions representing 13 countries has been elucidated using molecular analysis and biochemical traits. Seed kernel protein, oil content, ash content and phorbol esters revealed variation with accessions from Mexico containing low levels of phorbol esters. Molecular characterization disclosed polymorphism of 61.8 and 35.5% with RAPD and ISSR primers, respectively and Mantel test revealed positive correlation between the two marker systems. Dendrogram based on pairwise genetic similarities and three-dimensional principal coordinate analysis using data from RAPD and ISSR marker systems showed close clustering of accessions from all countries and grouped the Mexican accessions separately in clusters III, IV, V and VI. Presence of the toxic phorbol esters is a major concern and analysis of 28 Mexican accessions resulted in identification of molecular markers associated with high and low phorbol ester content. The identified RAPD and ISSR markers were converted to SCARs for increasing the reliability and use in marker assisted programmes aimed at development of accessions with reduced toxicity. Twelve microsatellite primers differentiated the non-toxic Mexican accessions and disclosed novel alleles in Mexican germplasm. Amplification with primers specific to the curcin coding sequence and promoter region of ribosome-inactivating protein (RIP) revealed polymorphism with one primer specific to RIP promoter region specifically in accessions with low phorbol ester levels. Narrow genetic variation among accessions from different regions of the world and rich diversity among Mexican genotypes in terms of phorbol ester content and distinct molecular profiles indicates the need for exploitation of germplasm from Mexico in J. curcas breeding programmes. [Copyright &y& Elsevier]

SAR studies for novel non-imidazole containing H3 receptor antagonists with high potency and selectivity for rat H3 receptors are described. A high throughput screening lead, A-923, was further elaborated in a systematic manner to clarify a pharmacophore for this class of aryloxyalkyl piperazine based compounds. [Copyright &y& Elsevier]