The genome sequence DataBase

The Genome Sequence DataBase (GSDB) is a database of publicly available nucleotide sequences and their associated biological and bibliographic information. Several notable changes have occurred in the past year: GSDB stopped accepting data submissions from researchers; ownership of data submitted to GSDB was transferred to GenBank; sequence analysis capabilities were expanded to include Smith-Waterman and Frame Search; and Sequence Viewer became available to Mac users. The content of GSDB remains up-to-date because publicly available data is acquired from the International Nucleotide Sequence Database Collaboration databases (IC) on a nightly basis. This allows GSDB to continue providing researchers with the ability to analyze, query and retrieve nucleotide sequences in the database. GSDB and its related tools are freely accessible from the URL: http://www.ncgr.org     

Twin peaks: the draft human genome sequence

Once thought to be impossible or a waste of resources, the initial high-volume stages of sequencing the human genome have been completed.     

BSMAP: whole genome bisulfite sequence MAPping program

Background  

Bisulfite sequencing is a powerful technique to study DNA cytosine methylation. Bisulfite treatment followed by PCR amplification specifically converts unmethylated cytosines to thymine. Coupled with next generation sequencing technology, it is able to detect the methylation status of every cytosine in the genome. However, mapping high-throughput bisulfite reads to the reference genome remains a great challenge due to the increased searching space, reduced complexity of bisulfite sequence, asymmetric cytosine to thymine alignments, and multiple CpG heterogeneous methylation.     

Beyond the sequence: cellular organization of genome function

Genomes are more than linear sequences. In vivo they exist as elaborate physical structures, and their functional properties are strongly determined by their cellular organization. I discuss here the functional relevance of spatial and temporal genome organization at three hierarchical levels: the organization of nuclear processes, the higher-order organization of the chromatin fiber, and the spatial arrangement of genomes within the cell nucleus. Recent insights into the cell biology of genomes have overturned long-held dogmas and have led to new models for many essential cellular processes, including gene expression and genome stability.     

Of mice and genome sequence

Availability of the mouse genome sequence will have a major impact on the study of vertebrate evolution, mammalian biology, and animal models of human disease. Resources to explore genome biology in mice will maximize the effect of this watershed event.     

Automated correction of genome sequence errors

By using information from an assembly of a genome, a new program called AutoEditor significantly improves base calling accuracy over that achieved by previous algorithms. This in turn improves the overall accuracy of genome sequences and facilitates the use of these sequences for polymorphism discovery. We describe the algorithm and its application in a large set of recent genome sequencing projects. The number of erroneous base calls in these projects was reduced by 80%. In an analysis of over one million corrections, we found that AutoEditor made just one error per 8828 corrections. By substantially increasing the accuracy of base calling, AutoEditor can dramatically accelerate the process of finishing genomes, which involves closing all gaps and ensuring minimum quality standards for the final sequence. It also greatly improves our ability to discover single nucleotide polymorphisms (SNPs) between closely related strains and isolates of the same species.     

Limitations of next-generation genome sequence assembly

High-throughput sequencing technologies promise to transform the fields of genetics and comparative biology by delivering tens of thousands of genomes in the near future. Although it is feasible to construct de novo genome assemblies in a few months, there has been relatively little attention to what is lost by sole application of short sequence reads. We compared the recent de novo assemblies using the short oligonucleotide analysis package (SOAP), generated from the genomes of a Han Chinese individual and a Yoruban individual, to experimentally validated genomic features. We found that de novo assemblies were 16.2% shorter than the reference genome and that 420.2 megabase pairs of common repeats and 99.1% of validated duplicated sequences were missing from the genome. Consequently, over 2,377 coding exons were completely missing. We conclude that high-quality sequencing approaches must be considered in conjunction with high-throughput sequencing for comparative genomics analyses and studies of genome evolution.     

Complete genome sequence of Pyrobaculum oguniense

Pyrobaculum oguniense TE7 is an aerobic hyperthermophilic crenarchaeon isolated from a hot spring in Japan. Here we describe its main chromosome of 2,436,033 bp, with three large-scale inversions and an extra-chromosomal element of 16,887 bp. We have annotated 2,800 protein-coding genes and 145 RNA genes in this genome, including nine H/ACA-like small RNA, 83 predicted C/D box small RNA, and 47 transfer RNA genes. Comparative analyses with the closest known relative, the anaerobe Pyrobaculum arsenaticum from Italy, reveals unexpectedly high synteny and nucleotide identity between these two geographically distant species. Deep sequencing of a mixture of genomic DNA from multiple cells has illuminated some of the genome dynamics potentially shared with other species in this genus.     

Complete genome sequence of Borrelia crocidurae

We announce the draft genome sequence of Borrelia crocidurae (strain Achema). The 1,557,560-bp genome (27% GC content) comprises one 919,477-bp linear chromosome and 638,083-bp plasmids that together carry 1,472 open reading frames, 32 tRNAs, and three complete rRNAs, with almost complete colinearity between B. crocidurae and Borrelia duttonii chromosomes.     

Complete genome sequence of ikoma lyssavirus

Lyssaviruses (family Rhabdoviridae) constitute one of the most important groups of viral zoonoses globally. All lyssaviruses cause the disease rabies, an acute progressive encephalitis for which, once symptoms occur, there is no effective cure. Currently available vaccines are highly protective against the predominantly circulating lyssavirus species. Using next-generation sequencing technologies, we have obtained the whole-genome sequence for a novel lyssavirus, Ikoma lyssavirus (IKOV), isolated from an African civet in Tanzania displaying clinical signs of rabies. Genetically, this virus is the most divergent within the genus Lyssavirus. Characterization of the genome will help to improve our understanding of lyssavirus diversity and enable investigation into vaccine-induced immunity and protection.     

Genome-tools: a flexible package for genome sequence analysis

Genome-tools is a Perl module, a set of programs, and a user interface that facilitates access to genome sequence information. The package is flexible, extensible, and designed to be accessible and useful to both nonprogrammers and programmers. Any relatively well-annotated genome available with standard GenBank genome files may be used with genome-tools. A simple Web-based front end permits searching any available genome with an intuitive interface. Flexible design choices also make it simple to handle revised versions of genome annotation files as they change. In addition, programmers can develop cross-genomic tools and analyses with minimal additional overhead by combining genome-tools modules with newly written modules. Genome-tools runs on any computer platform for which Perl is available, including Unix, Microsoft Windows, and Mac OS. By simplifying the access to large amounts of genomic data, genome-tools may be especially useful for molecular biologists looking at newly sequenced genomes, for which few informatics tools are available. The genome-tools Web interface is accessible at http://genome-tools.sourceforge.net, and the source code is available at http://sourceforge.net/projects/genome-tools.