Figure 1.
Homologous recombination of targeting constructs and subsequent neo cassette excision in ES cells. (A) Amino acid sequence alignment of the amino-terminal zinc fingers of GATA-1 and GATA-2. Mutated positions in GATA-1 and GATA-2 N-terminal zinc fingers (N-f) are indicated by the red “V” and residue number. Identical sequences are shown in black, and nonidentical residues are shown in blue. (B) Schematic representation of V205G KI mutation gene-targeting strategy into the GATA-1 locus on the X-chromosome. Subsequent Cre-mediated excision of neomycin resistance gene (neo) cassette is shown below. Solid triangles represent loxP sites. Location of probe used for Southern analysis is indicated by solid bar (probe A). PCR primers are shown as horizontally opposed arrows. (C) Southern blot and PCR analyses depicting correctly recombined and Cre-excised GATA-1KI loci. (D) Schematic representation of V296G KI targeting strategy in the GATA-2 locus and subsequent Cre-mediated excision of neo cassette. Locations of probes used for Southern analysis are indicated by solid bars (probes B and C). (E) Southern blot analysis depicting correctly recombined and Cre-excised GATA-2KI loci.