Figure 1.

Schematic of the wild-type agouti cDNA, the BAPaΔbasic transgene, and coat phenotype of three independently derived lines of BAPaΔbasic Tg mice (Tg/Tg). Key protein features encoded by the agouti cDNA are denoted: signal peptide (gray box), glycosylation site (stem/loop), basic region (yellow box), polyproline region (open box, Pro), and cysteine-rich region (diagonally striped box). The human β-actin promoter is denoted by the light blue box with an arrow. Deletion of the agouti basic domain in the BAPaΔbasic transgene is denoted by a single black line joining of the N- and C-terminal regions of the agouti cDNA. Tg mice that were 3–4 months old and attained by inbreeding hemizygous Tg mice (Tg/−) after backcrossing to the C57BL/6J strain for five generations are depicted with black non-Tg (a/a) littermates.