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941.
Swarup K. Parida Sanjay Kalia Awadhesh Pandit Preetam Nayak Ram Kushal Singh Kishor Gaikwad Prem Shankar Srivastava Nagendra K. Singh Trilochan Mohapatra 《Plant cell reports》2016,35(8):1629-1653
Key message
Single nucleotide polymorphism in sugar pathway and disease resistance genes showing genetic association with sugar content and red rot resistance would be useful in marker-assisted genetic improvement of sugarcane.Abstract
Validation and genotyping of potential sequence variants in candidate genes are necessary to understand their functional significance and trait association potential. We discovered, characterized, validated and genotyped SNPs and InDels in sugar pathway and disease resistance genes of Saccharum complex and sugarcane varieties using amplicon sequencing and CAPS assays. The SNPs were abundant in the non-coding 3′UTRs than 5′UTRs and coding sequences depicting a strong bias toward C to T transition substitutions than transversions. Sequencing of cloned amplicons validated 61.6 and 45.2 % SNPs detected in silico in 21 sugar pathway and 16 disease resistance genes, respectively. Sixteen SNPs in four sugar pathway genes and 10 SNPs in nine disease resistance genes were validated through cost-effective CAPS assay. Functional and adaptive significance of SNP and protein haplotypes identified in sugar pathway and disease resistance genes was assessed by correlating their allelic variation with missense amino acid substitutions in the functional domains, alteration in protein structure models and possible modulation of catalytic enzyme activity in contrasting high and low sugar and moderately red rot resistant and highly susceptible sugarcane genotypes. A strong genetic association of five SNPs in the sugar pathway and disease resistance genes, and an InDel marker in the promoter sequence of sucrose synthase-2 gene, with sugar content and red rot resistance, was evident. The functionally relevant SNPs and InDels, detected and validated in sugar pathway and disease resistance genes, and genic CAPS markers designed, would be of immense use in marker-assisted genetic improvement of sugarcane for sugar content and disease resistance.942.
Alistair J. Hobday Kevern Cochrane Nicola Downey-Breedt James Howard Shankar Aswani Val Byfield Greg Duggan Elethu Duna Leo X. C. Dutra Stewart D. Frusher Elizabeth A. Fulton Louise Gammage Maria A. Gasalla Chevon Griffiths Almeida Guissamulo Marcus Haward Astrid Jarre Sarah M. Jennings Tia Jordan Jessica Joyner Narayana Kumar Ramani Swathi Lekshmi Perumal Shanmugasundaram Willem Malherbe Kelly Ortega Cisneros Adina Paytan Gretta T. Pecl Éva E. Plagányi Ekaterina E. Popova Haja Razafindrainibe Michael Roberts Prathiba Rohit Shyam Salim Sainulabdeen Warwick Sauer Sathianandan Thayyil Valappil Paryiappanal Ulahannan Zacharia E. Ingrid van Putten 《Reviews in Fish Biology and Fisheries》2016,26(2):249-264
Many coastal communities rely on living marine resources for livelihoods and food security. These resources are commonly under stress from overfishing, pollution, coastal development and habitat degradation. Climate change is an additional stressor beginning to impact coastal systems and communities, but may also lead to opportunities for some species and the people they sustain. We describe the research approach for a multi-country project, focused on the southern hemisphere, designed to contribute to improving fishing community adaptation efforts by characterizing, assessing and predicting the future of coastal-marine food resources, and co-developing adaptation options through the provision and sharing of knowledge across fast-warming marine regions (i.e. marine ‘hotspots’). These hotspots represent natural laboratories for observing change and concomitant human adaptive responses, and for developing adaptation options and management strategies. Focusing on adaptation options and strategies for enhancing coastal resilience at the local level will contribute to capacity building and local empowerment in order to minimise negative outcomes and take advantage of opportunities arising from climate change. However, developing comparative approaches across regions that differ in political institutions, socio-economic community demographics, resource dependency and research capacity is challenging. Here, we describe physical, biological, social and governance tools to allow hotspot comparisons, and several methods to evaluate and enhance interactions within a multi-nation research team. Strong partnerships within and between the focal regions are critical to scientific and political support for development of effective approaches to reduce future vulnerability. Comparing these hotspot regions will enhance local adaptation responses and generate outcomes applicable to other regions. 相似文献
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946.
Dai C Li D Popovici-Muller J Zhao L Girijavallabhan VM Rosner KE Lavey BJ Rizvi R Shankar BB Wong MK Guo Z Orth P Strickland CO Sun J Niu X Chen S Kozlowski JA Lundell DJ Piwinski JJ Shih NY Siddiqui MA 《Bioorganic & medicinal chemistry letters》2011,21(10):3172-3176
TNF-α converting enzyme (TACE) inhibitors are promising agents to treat inflammatory disorders and cancer. We have investigated novel tartrate diamide TACE inhibitors where the tartrate core binds to zinc in a unique tridentate fashion. Incorporating (R)-2-(2-N-alkylaminothiazol-4-yl)pyrrolidines into the left hand side amide of the tartrate scaffold led to the discovery of potent and selective TACE inhibitors, some of which exhibited good rat oral bioavailability. 相似文献
947.
Epco Hasker Sangeeta Kansal Paritosh Malaviya Kamlesh Gidwani Albert Picado Rudra Pratap Singh Ankita Chourasia Abhishek Kumar Singh Ravi Shankar Joris Menten Mary Elizabeth Wilson Marleen Boelaert Shyam Sundar 《PLoS neglected tropical diseases》2013,7(2)
Introduction
Asymptomatic persons infected with the parasites causing visceral leishmaniasis (VL) usually outnumber clinically apparent cases by a ratio of 4–10 to 1. We describe patterns of markers of Leishmania donovani infection and clinical VL in relation to age in Bihar, India.Methods
We selected eleven villages highly endemic for Leishmania donovani. During a 1-year interval we conducted two house to house surveys during which we collected blood samples on filter paper from all consenting individuals aged 2 years and above. Samples were tested for anti-leishmania serology by Direct Agglutination Test (DAT) and rK39 ELISA. Data collected during the surveys included information on episodes of clinical VL among study participants.Results
We enrolled 13,163 persons; 6.2% were reactive to DAT and 5.9% to rK39. Agreement between the tests was weak (kappa = 0.30). Among those who were negative on both tests at baseline, 3.6% had converted to sero-positive on either of the two tests one year later. Proportions of sero-positives and sero-converters increased steadily with age. Clinical VL occurred mainly among children and young adults (median age 19 years).Discussion
Although infection with L. donovani is assumed to be permanent, serological markers revert to negative. Most VL cases occur at younger ages, yet we observed a steady increase with age in the frequency of sero-positivity and sero-conversion. Our findings can be explained by a boosting effect upon repeated exposure to the parasite or by intermittent release of parasites in infected subjects from safe target cells. A certain proportion of sero-negative subjects could have been infected but below the threshold of antibody abundance for our serologic testing. 相似文献948.
Wesley P. F. Máximo Jeffrey L. Howell Kanakachari Mogilicherla Moslem Basij Shankar C. R. R. Chereddy Subba R. Palli 《Archives of insect biochemistry and physiology》2020,104(4):e21685
The Colorado potato beetle (CPB; Leptinotarsa decemlineata) is one of the most notorious and difficult to control pests of potato and other solanaceous crops in North America. This insect has evolved a remarkable ability to detoxify both plant and synthetic toxins, allowing it to feed on solanaceous plants containing toxic alkaloids and to develop resistance to synthetic chemicals used for its control. RNA interference (RNAi) is a natural mechanism that evolved as an immune response to double-stranded RNA (dsRNA) viruses where dsRNA triggers silencing of target gene expression. RNAi is being developed as a method to control CPB. Here, we evaluated four CPB-specific genes to identify targets for RNAi-mediated control of this insect. Out of the four dsRNAs evaluated in CPB larvae and adults, dsIAP (dsRNA targeting inhibitor of apoptosis, iap gene) performed better than dsActin, dsHSP70, and dsDynamin in inducing larval mortality. However, in adults, the mortality induced by dsActin is significantly higher than the mortality induced by dsIAP, dsHSP70, and dsDynamin. Interestingly, a combination of dsIAP and dsActin performed better than either dsIAP or dsActin alone by inducing feeding inhibition in 24 hr and mortality in 48 hr in larvae. When the dsIAP and dsActin were expressed in the Escherichia coli HT115 strain and applied as a heat-killed bacterial spray on potato plants, it protected the plants from CPB damage. These studies show that the combination of dsIAP and dsActin shows promise as an insecticide to control CPB. 相似文献
949.
Pierre Gillotay Meghna Shankar Benoit Haerlingen Eski Sema Elif Macarena PozoMorales Ins Garteizgogeascoa Susanne Reinhardt Annekathrin Krnkel Juliane Blsche Andreas Petzold Nikolay Ninov Gokul Kesavan Christian Lange Michael Brand Anne Lefort Frdrick Libert Vincent Detours Sabine Costagliola Singh Sumeet Pal 《EMBO reports》2020,21(12)
950.
Prinja S Bahuguna P Pinto AD Sharma A Bharaj G Kumar V Tripathy JP Kaur M Kumar R 《PloS one》2012,7(1):e30362