Format

Send to

Choose Destination
Nat Biotechnol. 2003 Apr;21(4):443-7. Epub 2003 Mar 10.

Engineering the mouse genome with bacterial artificial chromosomes to create multipurpose alleles.

Author information

1
Biotec, Technische Universit├Ąt Dresden, GmbH, c/o Max Planck Institute for Molecular Cell Biology and Genetics, Pfotenhauerstr. 108, Dresden, Germany 01307.

Abstract

The mouse is the leading vertebrate model because its genome can be altered by both random transgenesis and homologous recombination with targeting constructs. Both approaches have been hindered by the size and site limitations implicit in conventional Escherichia coli DNA-engineering methods. Homologous recombination in E. coli, or 'recombineering', has overcome these limitations for bacterial artificial chromosome (BAC) transgenesis. Here we applied Red/ET recombineering (using the lambda Redalpha/Redbeta recombinase pair) to generate a 64 kilobase targeting construct that carried two selectable cassettes permitting the simultaneous mutation of the target gene, Mll, at sites 43 kb apart in one round of mouse embryonic stem (ES) cell targeting. The targeting frequency after dual selection was 6%. Because the two selectable cassettes were flanked by FRT or loxP sites, three more alleles can be generated by site-specific recombination. Our approach represents a simple way to introduce changes at two or more sites in a genetic locus, and thereafter generate allele combinations. The size of BAC templates offers new freedom for the design of targeting constructs. Combined with the use of two selectable cassettes placed far apart, BAC-based targeting constructs may be applicable to tasks such as regional exchanges, deletions, and insertions.

PMID:
12627172
DOI:
10.1038/nbt804
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center