Rapid isolation of Arabidopsis thaliana developing embryos

278 BioTechniques Vol. 35, No. 2 (2003) the selection of the vectors that are used in two-hybrid strategies. MG7α contains a deletion of the endA gene, compared to the point mutation in DH5α, which still allows for a residual level of endonuclease activity (14,15). The endA knock-out removes any residual endA activity and thus allows MG7α to produce higher quality plasmid DNA preparations than strains carrying endA point mutations. In addition to its use in the yeast two-hybrid system, the qualities that it inherits from its parent strain, DH5α, and the endA deletion we have introduced, make it a good all-purpose laboratory strain. This strain will be made available through ATCC (Reference no. MBA-78; Manassas, VA, USA).