Project description:Insect-borne diseases have experienced a troubling resurgence in recent years. Emergence of resistance to pesticides greatly hampers control efforts. Paratransgenesis, or the genetic transformation of bacterial symbionts of disease vectors, is an alternative to traditional approaches. Previously, we developed paratransgenic lines of Rhodnius prolixus, a vector of Chagas disease in Central America. Here, we report identification of a Corynebacterial species as a symbiont of Triatoma infestans, a leading vector of Chagas disease in South America. We have modified this bacterium to produce an immunologically active single chain antibody fragment, termed rDB3. This study establishes the basis for generating paratransgenic T. infestans as a strategy for control of Chagas disease.
Project description:Part of a set of highly integrated epigenome maps for Arabidopsis thaliana. Keywords: Illumina high-throughput bisulfite sequencing Whole genome shotgun bisulfite sequencing of wildtype Arabidopsis plants (Columbia-0), and met1, drm1 drm2 cmt3, and ros1 dml2 dml3 null mutants using the Illumina Genetic Analyzer.
Project description:We report a whole-genome shotgun assembly (called WGSA) of the human genome generated at Celera in 2001. The Celera-generated shotgun data set consisted of 27 million sequencing reads organized in pairs by virtue of end-sequencing 2-kbp, 10-kbp, and 50-kbp inserts from shotgun clone libraries. The quality-trimmed reads covered the genome 5.3 times, and the inserts from which pairs of reads were obtained covered the genome 39 times. With the nearly complete human DNA sequence [National Center for Biotechnology Information (NCBI) Build 34] now available, it is possible to directly assess the quality, accuracy, and completeness of WGSA and of the first reconstructions of the human genome reported in two landmark papers in February 2001 [Venter, J. C., Adams, M. D., Myers, E. W., Li, P. W., Mural, R. J., Sutton, G. G., Smith, H. O., Yandell, M., Evans, C. A., Holt, R. A., et al. (2001) Science 291, 1304-1351; International Human Genome Sequencing Consortium (2001) Nature 409, 860-921]. The analysis of WGSA shows 97% order and orientation agreement with NCBI Build 34, where most of the 3% of sequence out of order is due to scaffold placement problems as opposed to assembly errors within the scaffolds themselves. In addition, WGSA fills some of the remaining gaps in NCBI Build 34. The early genome sequences all covered about the same amount of the genome, but they did so in different ways. The Celera results provide more order and orientation, and the consortium sequence provides better coverage of exact and nearly exact repeats.
Project description:BACKGROUND:Most eukaryotic genomes include a substantial repeat-rich fraction termed heterochromatin, which is concentrated in centric and telomeric regions. The repetitive nature of heterochromatic sequence makes it difficult to assemble and analyze. To better understand the heterochromatic component of the Drosophila melanogaster genome, we characterized and annotated portions of a whole-genome shotgun sequence assembly. RESULTS:WGS3, an improved whole-genome shotgun assembly, includes 20.7 Mb of draft-quality sequence not represented in the Release 3 sequence spanning the euchromatin. We annotated this sequence using the methods employed in the re-annotation of the Release 3 euchromatic sequence. This analysis predicted 297 protein-coding genes and six non-protein-coding genes, including known heterochromatic genes, and regions of similarity to known transposable elements. Bacterial artificial chromosome (BAC)-based fluorescence in situ hybridization analysis was used to correlate the genomic sequence with the cytogenetic map in order to refine the genomic definition of the centric heterochromatin; on the basis of our cytological definition, the annotated Release 3 euchromatic sequence extends into the centric heterochromatin on each chromosome arm. CONCLUSIONS:Whole-genome shotgun assembly produced a reliable draft-quality sequence of a significant part of the Drosophila heterochromatin. Annotation of this sequence defined the intron-exon structures of 30 known protein-coding genes and 267 protein-coding gene models. The cytogenetic mapping suggests that an additional 150 predicted genes are located in heterochromatin at the base of the Release 3 euchromatic sequence. Our analysis suggests strategies for improving the sequence and annotation of the heterochromatic portions of the Drosophila and other complex genomes.
Project description:Rapid advances in high-throughput DNA sequencing technologies are accelerating the pace of research into personalized medicine. While methods for variant discovery and genotyping from whole genome sequencing (WGS) datasets have been well established, linking variants together into a single haplotype remains a challenge. An understanding of complete haplotypes of an individual will help clarify the consequences of inheriting multiple alleles in combination, identify novel disease associations, and augment studies of gene regulation. Although numerous methods have been developed to reconstruct haplotypes from WGS data, chromosome-span haplotypes at high resolution have been difficult to obtain. Here we present a novel method to accurately reconstruct chromosome-span haplotypes from proximity-ligation and DNA shotgun sequencing. We demonstrate the utility of this approach in producing high-resolution chromosome-span haplotype phasing in mouse and human. While proximity-ligation based methods were originally designed to investigate spatial organization of the genome, our results lend support for their use as a general tool for haplotyping in the future.