Background
The highly conserved human and mouse genomes comprise about 20,000 protein-coding genes of mostly unknown function. As part of an international programme aimed at mutating all protein-coding genes in the mouse, we use a combination of gene trapping and gene targeting technologies to generate a large public resource of reporter-tagged mutations in mouse ES cells for the functional annotation of the mouse genome. Mutant ES cells from this resource support the Sanger Institute Mouse Genetics Project and are available to the scientific community without restriction.
Research
Our aims

Formation of mesoderm in a gastrulating mouse embryo.
The Mouse developmental genetics and ES cell mutagenesis team has two major aims:
- The first is to produce mutant mouse embryonic stem (ES) cell resources for the scientific community.
- The second is to use these ES cell resources to understand the underlying genetic basis of early cell fate decisions in the mammalian embryo.
Our approach
A high-throughput gene targeting pipeline has been established at the Wellcome Trust Sanger Institute to deliver conditional targeted mutations in more than 10,000 genes in C57BL/6N ES cells. This effort requires the construction of vectors and the production of targeted mouse ES cells lines on an unprecedented scale. The Sanger Institute is a member of the International Knockout Mouse Consortium (IKMC) and contributes resources to the EUCOMM and KOMP projects.
Large-scale genetic screens in ES cells is hampered by the difficulty in generating homozygous mutant cells. Moreover, genes essential for the growth of stem cells require conditional strategies to recover and study loss-of-function mutations. Taking advantage of high-throughput gene targeting technology, we are developing high-efficiency strategies for the generation of conditional homozygous mutant ES cells by serial targeting and the use of ligand-inducible Cre recombinase. This approach permits the study of genes required for stem cell pluripotency and self-renewal.
Functional analysis chromatin proteins in early mouse development
It is abundantly clear that packaging of genomic DNA is not equivalent in all cell types and various epigenetic modifications profoundly influence the transcriptional competence of genes and developmental potential of cells. We are examining the function of chromatin-associated proteins in undifferentiated and differentiated ES cell cultures. These include components of the SWI/SNF chromatin-remodeling complexes, Polycomb group protein complexes and the nucleosome remodelling and deactylation (NuRD) complexes.
Proteomic analysis of chromatin proteins in ES cells
As part of the EUTRACC consortium, we have developed and validated a novel strategy for tagging of genes in ES cells for tandem-affinity purification-mass spectrometry (TAP-MS) analysis. This strategy ensures the expression of tagged proteins at endogenous levels and the generation of mice from tagged ES cells can be used to confirm the normal activity of the tagged protein. The analysis of protein-protein and protein-DNA interactions of selected chromatin proteins is currently underway.
Sanger Institute Gene Trap Resource
As a member of the International Gene Trap Consortium (IGTC), we use gene trapping to generate random insertional mutations in mouse ES cells for immediate molecular characterisation. The Sanger Institute Gene Trap Resource (SIGTR) contains more than 10,000 characterised gene trap insertions in 129P2 ES cells. SIGTR gene trap ES cell lines are available upon request from the University of California at Davis.
Resources
- High Throughput Gene Targeting (HTGT) - delivers conditional targeted mutations in more than 10,000 genes in C57BL/6N ES cells
- Sanger Institute Gene Trap Resource (SIGTR) - uses gene trapping to rapidly generate random insertional mutations in mouse ES cells for immediate molecular characterisation
Collaborations
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International Knockout Mouse Consortium (IKMC)
The International Knockout Mouse Consortium (IKMC) has established a common webportal for the dissemination of mutant ES cell resources to the scientific community. -
European Conditional Mouse Mutagenesis (EUCOMM)
Aims to generate a collection of up to 13,000 mutated genes in mouse C57BL/6N embryonic stem (ES) cells using conditional gene trapping and gene targeting approaches. -
The Knockout Mouse Project (KOMP)
Is a trans-NIH initiative that aims to generate a comprehensive and public resource comprised of mouse embryonic stem (ES) cells containing a null mutation in every gene in the mouse genome. -
International Gene Trap Consortium (IGTC)
A collaboration of laboratories around the world working together to generate a public library of mutated murine ES cell lines, which can be obtained on a non-collaborative basis by scientists interested in generating reporter-tagged, loss-of-function mutations in mice. -
European Transcriptome, Regulome & Cellular Commitment Consortium
(EUTRACC)
Aims to determine the regulation of the genome by mapping the regulatory pathways and networks of transcription factors that control cellular functions.
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Floxin, a resource for genetically engineering mouse ESCs.
Nature methods 2010;7;1;50-2
PUBMED: 19966808; PMC: 2895430; DOI: 10.1038/nmeth.1406
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Agouti C57BL/6N embryonic stem cells for mouse genetic resources.
Nature methods 2009;6;7;493-5
PUBMED: 19525957; PMC: 3555078; DOI: 10.1038/nmeth.1342
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Extensive genomic copy number variation in embryonic stem cells.
Proceedings of the National Academy of Sciences of the United States of America 2008;105;45;17453-6
PUBMED: 18988746; PMC: 2582305; DOI: 10.1073/pnas.0805638105
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Gene trapping in mouse embryonic stem cells.
Methods in molecular biology (Clifton, N.J.) 2008;461;133-48
PUBMED: 19030794; DOI: 10.1007/978-1-60327-483-8_9
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Modeling insertional mutagenesis using gene length and expression in murine embryonic stem cells.
PloS one 2007;2;7;e617
PUBMED: 17637833; PMC: 1910612; DOI: 10.1371/journal.pone.0000617
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The International Gene Trap Consortium Website: a portal to all publicly available gene trap cell lines in mouse.
Nucleic acids research 2006;34;Database issue;D642-8
PUBMED: 16381950; PMC: 1347459; DOI: 10.1093/nar/gkj097
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Two ways to trap a gene in mice.
Proceedings of the National Academy of Sciences of the United States of America 2005;102;37;13001-2
PUBMED: 16150712; PMC: 1201614; DOI: 10.1073/pnas.0506279102
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The knockout mouse project.
Nature genetics 2004;36;9;921-4
PUBMED: 15340423; PMC: 2716027; DOI: 10.1038/ng0904-921
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A public gene trap resource for mouse functional genomics.
Nature genetics 2004;36;6;543-4
PUBMED: 15167922; PMC: 2716026; DOI: 10.1038/ng0604-543
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BayGenomics: a resource of insertional mutations in mouse embryonic stem cells.
Nucleic acids research 2003;31;1;278-81
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Functional analysis of secreted and transmembrane proteins critical to mouse development.
Nature genetics 2001;28;3;241-9
PUBMED: 11431694; DOI: 10.1038/90074
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Defining brain wiring patterns and mechanisms through gene trapping in mice.
Nature 2001;410;6825;174-9
PUBMED: 11242070; DOI: 10.1038/35065539
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Gene trapping methods for the identification and functional analysis of cell surface proteins in mice.
Methods in enzymology 2000;328;592-615
PUBMED: 11075368
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Capturing novel mouse genes encoding chromosomal and other nuclear proteins.
Journal of cell science 1998;111 ( Pt 17);2575-85
PUBMED: 9701556
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Rapid sequence analysis of gene trap integrations to generate a resource of insertional mutations in mice.
Genome research 1997;7;3;293-8
PUBMED: 9074932
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Capturing genes encoding membrane and secreted proteins important for mouse development.
Proceedings of the National Academy of Sciences of the United States of America 1995;92;14;6592-6
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The identification of new genes: gene trapping in transgenic mice.
Current opinion in biotechnology 1993;4;6;684-9
PUBMED: 7764465
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A gene trap approach in mouse embryonic stem cells: the lacZ reported is activated by splicing, reflects endogenous gene expression, and is mutagenic in mice.
Genes & development 1992;6;6;903-18
PUBMED: 1592261
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Entrapment vectors: a new tool for mammalian genetics.
Bio/technology (Nature Publishing Company) 1990;8;9;827-31
PUBMED: 1366793
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Mouse embryonic stem cells and reporter constructs to detect developmentally regulated genes.
Science (New York, N.Y.) 1989;244;4903;463-5
PUBMED: 2497519
Team
No team members listed

Dr Bill Skarnes