MouseBook: an integrated portal of mouse resources.

The MouseBook (http://www.mousebook.org) databases and web portal provide access to information about mutant mouse lines held as live or cryopreserved stocks at MRC Harwell. The MouseBook portal integrates curated information from the MRC Harwell stock resource, and other Harwell databases, with information from external data resources to provide value-added information above and beyond what is available through other routes such as International Mouse Stain Resource (IMSR). MouseBook can be searched either using an intuitive Google style free text search or using the Mammalian Phenotype (MP) ontology tree structure. Text searches can be on gene, allele, strain identifier (e.g. MGI ID) or phenotype term and are assisted by automatic recognition of term types and autocompletion of gene and allele names covered by the database. Results are returned in a tabbed format providing categorized results identified from each of the catalogs in MouseBook. Individual result lines from each catalog include information on gene, allele, chromosomal location and phenotype, and provide a simple click-through link to further information as well as ordering the strain. The infrastructure underlying MouseBook has been designed to be extensible, allowing additional data sources to be added and enabling other sites to make their data directly available through MouseBook.

EMMA--mouse mutant resources for the international scientific community.

The laboratory mouse is the premier animal model for studying human disease and thousands of mutants have been identified or produced, most recently through gene-specific mutagenesis approaches. High throughput strategies by the International Knockout Mouse Consortium (IKMC) are producing mutants for all protein coding genes. Generating a knock-out line involves huge monetary and time costs so capture of both the data describing each mutant alongside archiving of the line for distribution to future researchers is critical. The European Mouse Mutant Archive (EMMA) is a leading international network infrastructure for archiving and worldwide provision of mouse mutant strains. It operates in collaboration with the other members of the Federation of International Mouse Resources (FIMRe), EMMA being the European component. Additionally EMMA is one of four repositories involved in the IKMC, and therefore the current figure of 1700 archived lines will rise markedly. The EMMA database gathers and curates extensive data on each line and presents it through a user-friendly website. A BioMart interface allows advanced searching including integrated querying with other resources e.g. Ensembl. Other resources are able to display EMMA data by accessing our Distributed Annotation System server. EMMA database access is publicly available at http://www.emmanet.org.

Novel gene function revealed by mouse mutagenesis screens for models of age-related disease.

Determining the genetic bases of age-related disease remains a major challenge requiring a spectrum of approaches from human and clinical genetics to the utilization of model organism studies. Here we report a large-scale genetic screen in mice employing a phenotype-driven discovery platform to identify mutations resulting in age-related disease, both late-onset and progressive. We have utilized N-ethyl-N-nitrosourea mutagenesis to generate pedigrees of mutagenized mice that were subject to recurrent screens for mutant phenotypes as the mice aged. In total, we identify 105 distinct mutant lines from 157 pedigrees analysed, out of which 27 are late-onset phenotypes across a range of physiological systems. Using whole-genome sequencing we uncover the underlying genes for 44 of these mutant phenotypes, including 12 late-onset phenotypes. These genes reveal a number of novel pathways involved with age-related disease. We illustrate our findings by the recovery and characterization of a novel mouse model of age-related hearing loss.

Route of exposure affects the oestrogenic response of fish to 4-tert-nonylphenol.

When toxicants cause effects to aquatic organisms, it is often unclear by what route, or routes, the toxicant entered the affected organism. The toxicity of a compound depends on its degree of uptake, distribution and metabolism, as well as its molecular interactions at the site of action. It was hypothesised, that a hydrophobic chemical such as 4-tert-nonylphenol (4-NP), entering via the gills/skin, may be more oestrogenic than one entering through the diet, because in the latter case it will undergo metabolism in the small intestine and liver before entering the bloodstream. In this way, metabolism may reduce or eliminate the oestrogenic potential of 4-NP before it reaches target organs such as the gonads or liver. To compare the potency of 4-tert-nonylphenol when administered via different routes, male fathead minnows (Pimephales promelas) were exposed to 4-NP either through waterborne exposure (experiment 1), or via the diet (experiment 2). Fish were exposed to 4-NP for 2 weeks either via the water at one of three nominal concentrations: 1, 10 or 50 microg/l (experiment 1) or 100, 500 or 1000 microg/day via the diet (experiment 2). Liver and blood samples were taken for vitellogenin mRNA and plasma vitellogenin quantification, respectively. Exposure of male fathead minnows to 50 microg/l of 4-NP in the water (experiment 1) and 500 and 1000 microg/day of 4-NP via the diet (experiment 2) induced vitellogenin mRNA. A similar pattern occurred for plasma vitellogenin induction, however, there was also a significant increase in plasma vitellogenin concentration in the fish exposed via the water to 10 microg/l of 4-NP. Using data from pharmacokinetics studies, an estimate for the total amount of 4-NP that entered the fish during each exposure was compared with the concentrations of plasma vitellogenin in each group of fish. The result showed a 10-fold greater sensitivity for 4-NP in fish exposed via the water compared with exposure via the oral route.Results obtained from this study indicate that a chemical such as 4-NP has a higher oestrogenic potential when it enters the bloodstream via the gills/skin of a fish compared with exposure through the diet.