The Experts below are selected from a list of 12363 Experts worldwide ranked by ideXlab platform

Guojie Zhang - One of the best experts on this subject based on the ideXlab platform.

  • identification and characterization of insect specific proteins by genome data analysis
    BMC Genomics, 2007
    Co-Authors: Junjie Shi, Hongkun Zheng, Terry Clark, Gane Kashu Wong, Xiaoling Wang, Hongsheng Wang, Guojie Zhang, Wen Wang
    Abstract:

    Insects constitute the vast majority of known species with their importance including biodiversity, agricultural, and human health concerns. It is likely that the successful adaptation of the Insecta clade depends on specific components in its proteome that give rise to specialized features. However, proteome determination is an intensive undertaking. Here we present results from a computational method that uses genome analysis to characterize insect and eukaryote proteomes as an approximation complementary to experimental approaches. Homologs in common to Drosophila melanogaster, Anopheles gambiae, Bombyx mori, Tribolium castaneum, and Apis mellifera were compared to the complete genomes of three non-insect eukaryotes (opisthokonts) Homo sapiens, Caenorhabditis elegans and Saccharomyces cerevisiae. This operation yielded 154 groups of orthologous proteins in Drosophila to be insect-specific homologs; 466 groups were determined to be common to eukaryotes (represented by three opisthokonts). ESTs from the hemimetabolous insect Locust migratoria were also considered in order to approximate their corresponding genes in the insect-specific homologs. Stress and stimulus response proteins were found to constitute a higher fraction in the insect-specific homologs than in the homologs common to eukaryotes. The significant representation of stress response and stimulus response proteins in proteins determined to be insect-specific, along with specific cuticle and pheromone/odorant binding proteins, suggest that communication and adaptation to environments may distinguish insect evolution relative to other eukaryotes. The tendency for low Ka/Ks ratios in the insect-specific protein set suggests purifying selection pressure. The generally larger number of paralogs in the insect-specific proteins may indicate adaptation to environment changes. Instances in our insect-specific protein set have been arrived at through experiments reported in the literature, supporting the accuracy of our approach.

  • identification and characterization of insect specific proteins by genome data analysis
    BMC Genomics, 2007
    Co-Authors: Junjie Shi, Hongkun Zheng, Terry Clark, Gane Kashu Wong, Xiaoling Wang, Hongsheng Wang, Guojie Zhang, Wen Wang
    Abstract:

    Background Insects constitute the vast majority of known species with their importance including biodiversity, agricultural, and human health concerns. It is likely that the successful adaptation of the Insecta clade depends on specific components in its proteome that give rise to specialized features. However, proteome determination is an intensive undertaking. Here we present results from a computational method that uses genome analysis to characterize insect and eukaryote proteomes as an approximation complementary to experimental approaches.

Heidi Goodrichblair - One of the best experts on this subject based on the ideXlab platform.

  • cpxra contributes to xenorhabdus nematophila virulence through regulation of lrha and modulation of insect immunity
    Applied and Environmental Microbiology, 2009
    Co-Authors: Erin Herbert E Tran, Heidi Goodrichblair
    Abstract:

    The gammaproteobacterium Xenorhabdus nematophila is a blood pathogen of insects that requires the CpxRA signal transduction system for full virulence (E. E. Herbert et al., Appl. Environ. Microbiol. 73:7826-7836, 2007). We show here that the Δ cpxR1 mutant has altered localization, growth, and immune suppressive activities relative to its wild-type parent during infection of Manduca sexta insects. In contrast to wild-type X. nematophila , which were recovered throughout infection, Δ cpxR1 cells did not accumulate in hemolymph until after insect death. In vivo imaging of fluorescently labeled bacteria within live insects showed that Δ cpxR1 displayed delayed accumulation and also occasionally were present in isolated nodes rather than systemically throughout the insect as was wild-type X. nematophila . In addition, in contrast to its wild-type parent, the Δ cpxR1 mutant elicited transcription of an insect antimicrobial peptide, cecropin. Relative to phosphate-buffered saline-injected insects, cecropin transcript was induced 21-fold more in insects injected with Δ cpxR1 and 2-fold more in insects injected with wild-type X. nematophila . These data suggest that the Δ cpxR1 mutant has a defect in immune suppression or has an increased propensity to activate M. sexta immunity. CpxR regulates, directly or indirectly, genes known or predicted to be involved in virulence (E. E. Herbert et al., Appl. Environ. Microbiol. 73:7826-7836, 2007), including lrhA , encoding a transcription factor necessary for X. nematophila virulence, motility, and lipase production (G. R. Richards et al., J. Bacteriol. 190:4870-4879, 2008). CpxR positively regulates lrhA transcript, and we have shown that altered regulation of lrhA in the Δ cpxR1 mutant causes this strain9s virulence defect. The Δ cpxR1 mutant expressing lrhA from a constitutive lac promoter showed wild-type virulence in M. sexta . These data suggest that CpxR contributes to X. nematophila virulence through the regulation of lrhA , immune suppression, and growth in Insecta .

  • cpxra contributes to xenorhabdus nematophila virulence through regulation of lrha and modulation of insect immunity
    Applied and Environmental Microbiology, 2009
    Co-Authors: Erin Herbert E Tran, Heidi Goodrichblair
    Abstract:

    The gammaproteobacterium Xenorhabdus nematophila is a blood pathogen of insects that requires the CpxRA signal transduction system for full virulence (E. E. Herbert et al., Appl. Environ. Microbiol. 73:7826-7836, 2007). We show here that the DeltacpxR1 mutant has altered localization, growth, and immune suppressive activities relative to its wild-type parent during infection of Manduca sexta insects. In contrast to wild-type X. nematophila, which were recovered throughout infection, DeltacpxR1 cells did not accumulate in hemolymph until after insect death. In vivo imaging of fluorescently labeled bacteria within live insects showed that DeltacpxR1 displayed delayed accumulation and also occasionally were present in isolated nodes rather than systemically throughout the insect as was wild-type X. nematophila. In addition, in contrast to its wild-type parent, the DeltacpxR1 mutant elicited transcription of an insect antimicrobial peptide, cecropin. Relative to phosphate-buffered saline-injected insects, cecropin transcript was induced 21-fold more in insects injected with DeltacpxR1 and 2-fold more in insects injected with wild-type X. nematophila. These data suggest that the DeltacpxR1 mutant has a defect in immune suppression or has an increased propensity to activate M. sexta immunity. CpxR regulates, directly or indirectly, genes known or predicted to be involved in virulence (E. E. Herbert et al., Appl. Environ. Microbiol. 73:7826-7836, 2007), including lrhA, encoding a transcription factor necessary for X. nematophila virulence, motility, and lipase production (G. R. Richards et al., J. Bacteriol. 190:4870-4879, 2008). CpxR positively regulates lrhA transcript, and we have shown that altered regulation of lrhA in the DeltacpxR1 mutant causes this strain's virulence defect. The DeltacpxR1 mutant expressing lrhA from a constitutive lac promoter showed wild-type virulence in M. sexta. These data suggest that CpxR contributes to X. nematophila virulence through the regulation of lrhA, immune suppression, and growth in Insecta.

Wen Wang - One of the best experts on this subject based on the ideXlab platform.

  • identification and characterization of insect specific proteins by genome data analysis
    BMC Genomics, 2007
    Co-Authors: Junjie Shi, Hongkun Zheng, Terry Clark, Gane Kashu Wong, Xiaoling Wang, Hongsheng Wang, Guojie Zhang, Wen Wang
    Abstract:

    Insects constitute the vast majority of known species with their importance including biodiversity, agricultural, and human health concerns. It is likely that the successful adaptation of the Insecta clade depends on specific components in its proteome that give rise to specialized features. However, proteome determination is an intensive undertaking. Here we present results from a computational method that uses genome analysis to characterize insect and eukaryote proteomes as an approximation complementary to experimental approaches. Homologs in common to Drosophila melanogaster, Anopheles gambiae, Bombyx mori, Tribolium castaneum, and Apis mellifera were compared to the complete genomes of three non-insect eukaryotes (opisthokonts) Homo sapiens, Caenorhabditis elegans and Saccharomyces cerevisiae. This operation yielded 154 groups of orthologous proteins in Drosophila to be insect-specific homologs; 466 groups were determined to be common to eukaryotes (represented by three opisthokonts). ESTs from the hemimetabolous insect Locust migratoria were also considered in order to approximate their corresponding genes in the insect-specific homologs. Stress and stimulus response proteins were found to constitute a higher fraction in the insect-specific homologs than in the homologs common to eukaryotes. The significant representation of stress response and stimulus response proteins in proteins determined to be insect-specific, along with specific cuticle and pheromone/odorant binding proteins, suggest that communication and adaptation to environments may distinguish insect evolution relative to other eukaryotes. The tendency for low Ka/Ks ratios in the insect-specific protein set suggests purifying selection pressure. The generally larger number of paralogs in the insect-specific proteins may indicate adaptation to environment changes. Instances in our insect-specific protein set have been arrived at through experiments reported in the literature, supporting the accuracy of our approach.

  • identification and characterization of insect specific proteins by genome data analysis
    BMC Genomics, 2007
    Co-Authors: Junjie Shi, Hongkun Zheng, Terry Clark, Gane Kashu Wong, Xiaoling Wang, Hongsheng Wang, Guojie Zhang, Wen Wang
    Abstract:

    Background Insects constitute the vast majority of known species with their importance including biodiversity, agricultural, and human health concerns. It is likely that the successful adaptation of the Insecta clade depends on specific components in its proteome that give rise to specialized features. However, proteome determination is an intensive undertaking. Here we present results from a computational method that uses genome analysis to characterize insect and eukaryote proteomes as an approximation complementary to experimental approaches.

Erin Herbert E Tran - One of the best experts on this subject based on the ideXlab platform.

  • cpxra contributes to xenorhabdus nematophila virulence through regulation of lrha and modulation of insect immunity
    Applied and Environmental Microbiology, 2009
    Co-Authors: Erin Herbert E Tran, Heidi Goodrichblair
    Abstract:

    The gammaproteobacterium Xenorhabdus nematophila is a blood pathogen of insects that requires the CpxRA signal transduction system for full virulence (E. E. Herbert et al., Appl. Environ. Microbiol. 73:7826-7836, 2007). We show here that the Δ cpxR1 mutant has altered localization, growth, and immune suppressive activities relative to its wild-type parent during infection of Manduca sexta insects. In contrast to wild-type X. nematophila , which were recovered throughout infection, Δ cpxR1 cells did not accumulate in hemolymph until after insect death. In vivo imaging of fluorescently labeled bacteria within live insects showed that Δ cpxR1 displayed delayed accumulation and also occasionally were present in isolated nodes rather than systemically throughout the insect as was wild-type X. nematophila . In addition, in contrast to its wild-type parent, the Δ cpxR1 mutant elicited transcription of an insect antimicrobial peptide, cecropin. Relative to phosphate-buffered saline-injected insects, cecropin transcript was induced 21-fold more in insects injected with Δ cpxR1 and 2-fold more in insects injected with wild-type X. nematophila . These data suggest that the Δ cpxR1 mutant has a defect in immune suppression or has an increased propensity to activate M. sexta immunity. CpxR regulates, directly or indirectly, genes known or predicted to be involved in virulence (E. E. Herbert et al., Appl. Environ. Microbiol. 73:7826-7836, 2007), including lrhA , encoding a transcription factor necessary for X. nematophila virulence, motility, and lipase production (G. R. Richards et al., J. Bacteriol. 190:4870-4879, 2008). CpxR positively regulates lrhA transcript, and we have shown that altered regulation of lrhA in the Δ cpxR1 mutant causes this strain9s virulence defect. The Δ cpxR1 mutant expressing lrhA from a constitutive lac promoter showed wild-type virulence in M. sexta . These data suggest that CpxR contributes to X. nematophila virulence through the regulation of lrhA , immune suppression, and growth in Insecta .

  • cpxra contributes to xenorhabdus nematophila virulence through regulation of lrha and modulation of insect immunity
    Applied and Environmental Microbiology, 2009
    Co-Authors: Erin Herbert E Tran, Heidi Goodrichblair
    Abstract:

    The gammaproteobacterium Xenorhabdus nematophila is a blood pathogen of insects that requires the CpxRA signal transduction system for full virulence (E. E. Herbert et al., Appl. Environ. Microbiol. 73:7826-7836, 2007). We show here that the DeltacpxR1 mutant has altered localization, growth, and immune suppressive activities relative to its wild-type parent during infection of Manduca sexta insects. In contrast to wild-type X. nematophila, which were recovered throughout infection, DeltacpxR1 cells did not accumulate in hemolymph until after insect death. In vivo imaging of fluorescently labeled bacteria within live insects showed that DeltacpxR1 displayed delayed accumulation and also occasionally were present in isolated nodes rather than systemically throughout the insect as was wild-type X. nematophila. In addition, in contrast to its wild-type parent, the DeltacpxR1 mutant elicited transcription of an insect antimicrobial peptide, cecropin. Relative to phosphate-buffered saline-injected insects, cecropin transcript was induced 21-fold more in insects injected with DeltacpxR1 and 2-fold more in insects injected with wild-type X. nematophila. These data suggest that the DeltacpxR1 mutant has a defect in immune suppression or has an increased propensity to activate M. sexta immunity. CpxR regulates, directly or indirectly, genes known or predicted to be involved in virulence (E. E. Herbert et al., Appl. Environ. Microbiol. 73:7826-7836, 2007), including lrhA, encoding a transcription factor necessary for X. nematophila virulence, motility, and lipase production (G. R. Richards et al., J. Bacteriol. 190:4870-4879, 2008). CpxR positively regulates lrhA transcript, and we have shown that altered regulation of lrhA in the DeltacpxR1 mutant causes this strain's virulence defect. The DeltacpxR1 mutant expressing lrhA from a constitutive lac promoter showed wild-type virulence in M. sexta. These data suggest that CpxR contributes to X. nematophila virulence through the regulation of lrhA, immune suppression, and growth in Insecta.

Guy Smagghe - One of the best experts on this subject based on the ideXlab platform.

  • Diversity in Protein Glycosylation among Insect Species
    2016
    Co-Authors: Guy Smagghe, Gerben Menschaert, Nagender Rao, Kris Gevaert, Els J. M. Van Damme
    Abstract:

    Background: A very common protein modification in multicellular organisms is protein glycosylation or the addition of carbohydrate structures to the peptide backbone. Although the Class of the Insecta is the largest animal taxon on Earth, almost all information concerning glycosylation in insects is derived from studies with only one species, namely the fruit fly Drosophila melanogaster. Methodology/Principal Findings: In this report, the differences in glycoproteomes between insects belonging to several economically important insect orders were studied. Using GNA (Galanthus nivalis agglutinin) affinity chromatography, different sets of glycoproteins with mannosyl-containing glycan structures were purified from the flour beetle (Tribolium castaneum), the silkworm (Bombyx mori), the honeybee (Apis mellifera), the fruit fly (D. melanogaster) and the pea aphid (Acyrthosiphon pisum). To identify and characterize the purified glycoproteins, LC-MS/MS analysis was performed. For all insect species, it was demonstrated that glycoproteins were related to a broad range of biological processes and molecular functions. Moreover, the majority of glycoproteins retained on the GNA column were unique to one particular insect species and only a few glycoproteins were present in the five different glycoprotein sets. Furthermore, these data support the hypothesis that insect glycoproteins can be decorated with mannosylated O-glycans. Conclusions/Significance: The results presented here demonstrate that oligomannose N-glycosylation events are highl

  • mechanisms of dsrna uptake in insects and potential of rnai for pest control a review
    Journal of Insect Physiology, 2010
    Co-Authors: Hanneke Huvenne, Guy Smagghe
    Abstract:

    RNA interference already proved its usefulness in functional genomic research on insects, but it also has considerable potential for the control of pest insects. For this purpose, the insect should be able to autonomously take up the dsRNA, for example through feeding and digestion in its midgut. In this review we bring together current knowledge on the uptake mechanisms of dsRNA in insects and the potential of RNAi to affect pest insects. At least two pathways for dsRNA uptake in insects are described: the transmembrane channel-mediated uptake mechanism based on Caenorhabditis elegans’ SID-1 protein and an ‘alternative’ endocytosis-mediated uptake mechanism. In the second part of the review dsRNA feeding experiments on insects are brought together for the first time, highlighting the achievement of implementing RNAi in insect control with the first successful experiments in transgenic plants and the diversity of successfully tested insect orders/species and target genes. We conclude with points of discussion and concerns regarding further research on dsRNA uptake mechanisms and the promising application possibilities for RNAi in insect control.

  • halloween genes and nuclear receptors in ecdysteroid biosynthesis and signalling in the pea aphid
    Insect Molecular Biology, 2010
    Co-Authors: Olivier Christiaens, Rodrigo A Velarde, Pierre Rougé, Guy Smagghe
    Abstract:

    The pea aphid (Acyrthosiphon pisum) is the first whole genome sequenced insect with a hemimetabolic development and an emerging model organism for studies in ecology, evolution and development. The insect steroid moulting hormone 20-hydroxyecdysone (20E) controls and coordinates development in insects, especially the moulting/metamorphosis process. We, therefore present here a comprehensive characterization of the Halloween genes phantom, disembodied, shadow, shade, spook and spookiest, coding for the P450 enzymes that control the biosynthesis of 20E. Regarding the presence of nuclear receptors in the pea aphid genome, we found 19 genes, representing all of the seven known subfamilies. The annotation and phylogenetic analysis revealed a strong conservation in the class of Insecta. But compared with other sequenced insect genomes, three orthologues are missing in the Acyrthosiphon genome, namely HR96, PNR-like and Knirps. We also cloned the EcR, Usp, E75 and HR3. Finally, 3D-modelling of the ligand-binding domain of Ap-EcR exhibited the typical canonical structural scaffold with 12 α-helices associated with a short hairpin of two antiparallel β-strands. Upon docking, 20E was located in the hormone-binding groove, supporting the hypothesis that EcR has a role in 20E signalling.