PubMed Health⌕ Search

Biomedical subjects

Rachel L Roper

Publications and source records attributed to Rachel L Roper.

6 recordsLinked to original sources

JDotter: a Java interface to multiple dotplots generated by dotter.

UNLABELLED: Java-Dotter (JDotter) is a platform-independent Java interactive interface for the Linux version of Dotter, a widely used program for generating dotplots of large DNA or protein sequences. JDotter runs as a client-server application and can send new sequences to the Dotter program for alignment as well as rapidly access a repository of preprocessed dotplots. JDotter also interfaces with a sequence database or file system to display supplementary feature data. Thus, JDotter greatly simplifies access to dotplot data in laboratories that deal with large numbers of genomes and have a multi-platform organization. AVAILABILITY: Currently, JDotter is used via Java Web Start by the Poxvirus Bioinformatics Resource for examining dotplots of complete poxvirus genomes; http://athena.bioc.uvic.ca/pbr/jdotter/. The software is available for download from the same location. SUPPLEMENTARY INFORMATION: Installation instructions, the User's Manual, screenshots and examples are available at the JDotter home page http://athena.bioc.uvic.ca/pbr/jdotter/. The software and source code is free for non-commercial applications.

Computer Graphics↗

Rapid preparation of vaccinia virus DNA template for analysis and cloning by PCR.

This chapter describes the preparation of template DNA from poxvirus-infected cells, plaques, or crude virus stocks for polymerase chain reaction (PCR) amplification. The advantages of this technique are that it is rapid, inexpensive, and, most importantly, reliable, requiring only centrifugation, detergent, and protease treatment. The template preparation is suitable for PCR amplification for screening viruses, cloning, transfection, and DNA sequencing.

Cloning, Molecular↗

The Genome sequence of the SARS-associated coronavirus.

We sequenced the 29,751-base genome of the severe acute respiratory syndrome (SARS)-associated coronavirus known as the Tor2 isolate. The genome sequence reveals that this coronavirus is only moderately related to other known coronaviruses, including two human coronaviruses, HCoV-OC43 and HCoV-229E. Phylogenetic analysis of the predicted viral proteins indicates that the virus does not closely resemble any of the three previously known groups of coronaviruses. The genome sequence will aid in the diagnosis of SARS virus infection in humans and potential animal hosts (using polymerase chain reaction and immunological tests), in the development of antivirals (including neutralizing antibodies), and in the identification of putative epitopes for vaccine development.

3' Untranslated Regions↗

Poxvirus orthologous clusters: toward defining the minimum essential poxvirus genome.

Increasingly complex bioinformatic analysis is necessitated by the plethora of sequence information currently available. A total of 21 poxvirus genomes have now been completely sequenced and annotated, and many more genomes will be available in the next few years. First, we describe the creation of a database of continuously corrected and updated genome sequences and an easy-to-use and extremely powerful suite of software tools for the analysis of genomes, genes, and proteins. These tools are available free to all researchers and, in most cases, alleviate the need for using multiple Internet sites for analysis. Further, we describe the use of these programs to identify conserved families of genes (poxvirus orthologous clusters) and have named the software suite POCs, which is available at www.poxvirus.org. Using POCs, we have identified a set of 49 absolutely conserved gene families-those which are conserved between the highly diverged families of insect-infecting entomopoxviruses and vertebrate-infecting chordopoxviruses. An additional set of 41 gene families conserved in chordopoxviruses was also identified. Thus, 90 genes are completely conserved in chordopoxviruses and comprise the minimum essential genome, and these will make excellent drug, antibody, vaccine, and detection targets. Finally, we describe the use of these tools to identify necessary annotation and sequencing updates in poxvirus genomes. For example, using POCs, we identified 19 genes that were widely conserved in poxviruses but missing from the vaccinia virus strain Tian Tan 1998 GenBank file. We have reannotated and resequenced fragments of this genome and verified that these genes are conserved in Tian Tan. The results for poxvirus genes and genomes are discussed in light of evolutionary processes.

Amino Acid Sequence↗

Prostaglandin E2 and cAMP promote B lymphocyte class switching to IgG1.

Prostaglandins of the E series (PGE) have traditionally been considered as suppressive for immune responses; however, recent data suggest that PGE channels the immune response towards a T helper 2 type response and production of selected immunoglobulin isotypes. Herein, we present data showing that PGE(2) and other agents that induce intracellular rises in cAMP significantly increased B lymphocyte IgG1 production (up to sevenfold). PGE(2) acted on small resting B cells and on uncommitted B cells expressing high levels of surface IgM to increase the number of cells secreting IgG1. PGE(2) even increased IgG1 synthesis by purified B cells in the absence of exogenous IL-4. Finally, PGE(2) synergized with IL-4 to induce germline gamma1 transcripts through the switch region. This transcription is required for isotype switching. These data support the hypothesis that PGE(2) acts on uncommitted resting B cells at the level of germline gamma1 transcription to promote class switching to IgG1. PGE(2) is an important regulator of the immune response, shifting the balance towards a T helper type 2 response, directing selection of the isotypes produced, and promoting memory cell formation.

Adjuvants, Immunologic↗

Poxvirus Orthologous Clusters (POCs).

Poxvirus Orthologous Clusters (POCs) is a JAVA client-server application which accesses an updated database containing all complete poxvirus genomes; it automatically groups orthologous genes into families based on BLASTP scores for assessment by a human database curator. POCs has a user-friendly interface permitting complex SQL queries to retrieve interesting groups of DNA and protein sequences as well as gene families for subsequent interrogation by a variety of integrated tools: BLASTP, BLASTX, TBLASTN, Jalview (multiple alignment), Dotlet (Dotplot), Laj (local alignment), and NAP (nucleotide to amino acid alignment).

Cluster Analysis↗