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Genomics Studies (genomics + studies)
Kinds of Genomics Studies Selected AbstractsFunctional genomics studies on the innate immunity of disease vectorsINSECT SCIENCE, Issue 1 2008Luke A. Baton Abstract The increasing availability of genome sequences and the development of high-throughput techniques for gene expression profiling and functional characterization are transforming the study of innate immunity and other areas of insect biology. Already, functional genomic approaches have enabled a quantum advance in the characterization of mosquito immune responses to malaria parasite infection, and similar high-throughput functional genomic studies of other vector-pathogen interactions can be expected in the near future. The application of microarray-based and other expression analyses provide genome-wide transcriptional profiles that can be used to identify insect immune system components that are differentially regulated upon exposure to various classes of pathogens, including many important etiologic agents of human and animal diseases. The role of infection-responsive or other candidate immune genes identified through comparative genomic approaches can then be functionally characterized, either in vivo, for instance in adult mosquitoes, or in vitro using cell lines. In most insect vectors of human pathogens, germ-line transgenesis is still technically difficult and maintenance of multiple transgenic lines logistically demanding. Consequently, transient RNA interference (RNAi)-mediated gene-silencing has rapidly become the method of choice for functional characterization of candidate innate immune genes. The powerful combination of transcriptional profiling in conjunction with assays using RNAi to determine gene function, and identify regulatory pathways, together with downstream cell biological approaches to determine protein localization and interactions, will continue to provide novel insights into the role of insect innate immunity in a variety of vector-pathogen interactions. Here we review advances in functional genomics studies of innate immunity in the insect disease vectors, over the past decade, with a particular focus on the Anopheles mosquito and its responses to malaria infection. [source] Proteome analysis of non-model plants: A challenging but powerful approachMASS SPECTROMETRY REVIEWS, Issue 4 2008Sebastien Christian Carpentier Abstract Biological research has focused in the past on model organisms and most of the functional genomics studies in the field of plant sciences are still performed on model species or species that are characterized to a great extent. However, numerous non-model plants are essential as food, feed, or energy resource. Some features and processes are unique to these plant species or families and cannot be approached via a model plant. The power of all proteomic and transcriptomic methods, that is, high-throughput identification of candidate gene products, tends to be lost in non-model species due to the lack of genomic information or due to the sequence divergence to a related model organism. Nevertheless, a proteomics approach has a great potential to study non-model species. This work reviews non-model plants from a proteomic angle and provides an outline of the problems encountered when initiating the proteome analysis of a non-model organism. The review tackles problems associated with (i) sample preparation, (ii) the analysis and interpretation of a complex data set, (iii) the protein identification via MS, and (iv) data management and integration. We will illustrate the power of 2DE for non-model plants in combination with multivariate data analysis and MS/MS identification and will evaluate possible alternatives. © 2008 Wiley Periodicals, Inc., Mass Spec Rev 27: 354,377, 2008 [source] A gene-based SNP linkage map for pacific white shrimp, Litopenaeus vannameiANIMAL GENETICS, Issue 3 2010Z.-Q. Du Summary Pacific white shrimp (Litopenaeus vannamei) are of particular economic importance to the global shrimp aquaculture industry. However, limited genomics information is available for the penaeid species. We utilized the limited public information available, mainly single nucleotide polymorphisms (SNPs) and expressed sequence tags, to discover markers for the construction of the first SNP genetic map for Pacific white shrimp. In total, 1344 putative SNPs were discovered, and out of 825 SNPs genotyped, 418 SNP markers from 347 contigs were mapped onto 45 sex-averaged linkage groups, with approximate coverage of 2071 and 2130 cm for the female and male maps, respectively. The average-squared correlation coefficient (r2), a measure of linkage disequilibrium, for markers located more than 50 cm apart on the same linkage group, was 0.15. Levels of r2 increased with decreasing inter-marker distance from ,80 cm, and increased more rapidly from ,30 cm. A QTL for shrimp gender was mapped on linkage group 13. Comparative mapping to model organisms, Daphnia pulex and Drosophila melanogaster, revealed extensive rearrangement of genome architecture for L. vannamei, and that L. vannamei was more related to Daphnia pulex. This SNP genetic map lays the foundation for future shrimp genomics studies, especially the identification of genetic markers or regions for economically important traits. [source] The influence of extracellular matrix and prolactin on global gene expression profiles of primary bovine mammary epithelial cells in vitroANIMAL GENETICS, Issue 1 2010L. G. Riley Summary An in vitro bovine mammosphere model was characterized for use in lactational biology studies using a functional genomics approach. Primary bovine mammary epithelial cells cultured on a basement membrane, Matrigel, formed three-dimensional alveoli-like structures or mammospheres. Gene expression profiling during mammosphere formation by high-density microarray analysis indicated that mammospheres underwent similar molecular and cellular processes to developing alveoli in the mammary gland. Gene expression profiles indicated that genes involved in milk protein and fat biosynthesis were expressed, however, lactose biosynthesis may have been compromised. Investigation of factors influencing mammosphere formation revealed that extracellular matrix (ECM) was responsible for the initiation of this process and that prolactin (Prl) was necessary for high levels of milk protein expression. CSN3 (encoding ,-casein) was the most highly expressed casein gene, followed by CSN1S1 (encoding ,S1-casein) and CSN2 (encoding ,-casein). Eighteen Prl-responsive genes were identified, including CSN1S1, SOCS2 and CSN2, however, expression of CSN3 was not significantly increased by Prl and CSN1S2 was not expressed at detectable levels in mammospheres. A number of novel Prl responsive genes were identified, including ECM components and genes involved in differentiation and apoptosis. This mammosphere model is a useful model system for functional genomics studies of certain aspects of dairy cattle lactation. [source] Prospects for molecular breeding of barleyANNALS OF APPLIED BIOLOGY, Issue 1 2003W T B THOMAS Summary Data from UK Recommended List Trials showed that the introduction of new cultivars of spring and winter barley has maintained a significant increase in yield over time, whereas there has been no significant improvement in hot water extract, the major determinant of good malting quality, in either crop. Commercial barley breeding is based upon phenotypic selection, and the introduction of molecular breeding methods must either increase the rate of advance, or offer an improvement in the cost-effectiveness of breeding programmes. Molecular breeding can be applied to either single gene or polygenic characters but is not widely used in commercial barley breeding, other than as a marker for resistance to the Barley Yellow Mosaic Virus complex. There are many reports of potential targets for use in molecular breeding but the few validation studies that have been carried out to date are disappointing. Results from genomics studies are likely to lead to the identification of key candidate genes, which can be associated with economically important characters through co-location on certain chromosomal regions. Associations between candidate gene sequence haplotypes and phenotypic characteristics is expected to identify allelic combinations, which are most frequently observed in successful cultivars, that can be used in molecular breeding of barley on a commercial scale. [source] A large-scale, high-efficiency and low-cost platform for structural genomics studiesACTA CRYSTALLOGRAPHICA SECTION D, Issue 8 2006Xiao-Dong Su A large-scale, high-efficiency and low-cost platform based on a Beckman Coulter Biomek FX and custom-made automation systems for structural genomics has been set up at Peking University, Beijing, People's Republic of China. This platform has the capacity to process up to 2000 genes per year for structural and functional analyses. Bacillus subtilis, a model organism for Gram-positive bacteria, and Streptococcus mutans, a major pathogen of dental caries, were selected as the main targets. To date, more than 470 B. subtilis and 1200 S.,mutans proteins and hundreds of proteins from other sources, including human liver proteins, have been selected as targets for this platform. The selected genes are mainly related to important metabolism pathways and/or have potential relevance for drug design. To date, 40 independent structures have been determined; of these 11 are in the category of novel structures by the criterion of having less than 30% sequence identity to known structures. More than 13 structures were determined by SAD/MAD phasing. The macromolecular crystallography beamline at the Beijing Synchrotron Radiation Facility and modern phasing programs have been crucial components of the operation of the platform. The idea and practice of the genomic approach have been successfully adopted in a moderately funded structural biology program and it is believed this adaptation will greatly improve the production of protein structures. The goal is to be able to solve a protein structure of moderate difficulty at a cost about US $10,000. [source] Structure of the hypothetical protein AQ_1354 from Aquifex aeolicusACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2003Vaheh Oganesyan The crystal structure of a hypothetical protein AQ_1354 (gi 2983779) from the hyperthermophilic bacteria Aquifex aeolicus has been determined using X-ray crystallography. As found in many structural genomics studies, this protein is not associated with any known function based on its amino-acid sequence. PSI-BLAST analysis against a non-redundant sequence database gave 68 similar sequences referred to as `conserved hypothetical proteins' from the uncharacterized protein family UPF0054 (accession No. PF02310). Crystallographic analysis revealed that the overall fold of this protein consists of one central ,-helix surrounded by a four-stranded ,-sheet and four other ,-helices. Structure-based homology analysis with DALI revealed that the structure has a moderate to good resemblance to metal-dependent proteinases such as collagenases and gelatinases, thus suggesting its possible molecular function. However, experimental tests for collagenase and gelatinase-type function show no detectable activity under standard assay conditions. Therefore, we suggest either that the members of the UPF0054 family have a similar fold but different biochemical functions to those of collagenases and gelatinases or that they have a similar function but perform it under different conditions. [source] Variation of linalool and geraniol content within two pairs of aromatic and non-aromatic grapevine clonesAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 2 2009E. DUCHÊNE Abstract Backgrounds and Aims:, In order to assess the suitability of some genotypes for functional genomics studies on terpenol synthesis in grapevine, two pairs of cultivars differing in their aromatic pattern were compared: Gewurztraminer and Savagnin Rose and two clones of Chardonnay (76 and 809). Methods and Results:, The genetic analysis based on microsatellite markers showed that Gewurztraminer and Savagnin Rose were clones derived from a single mother plant. The same result was found for Chardonnay clones 76 and 809. Analyses of wines, musts and berries showed that linalool and geraniol were present only at very low concentrations in Savagnin Rose and Chardonnay 76, both considered as non-aromatic cultivars. On the contrary, Gewurztraminer was characterised by a high geraniol content and Chardonnay 809 by a profile where linalool was predominant. Results obtained in the vineyard were consistent with data on fruiting cuttings in the greenhouse. Analyses of the terpenol content of berries from self-progenies plants of Gewurztraminer and Chardonnay 809 showed that this trait was heritable. Conclusions:, We provide evidence that clonal variation, through somatic mutations, can modify the aromatic profile of fruits. Significance of the Study:, We have characterised grapevine clones consistently differing in the terpenol content of both grapes and wines. Such plant material is appropriate for functional genomics studies. [source] |