Fig. 1. The structure of the Tribolium br gene inferred from the genome and the isolated mRNA of br isoforms identified in the present study. Five zinc-finger domains (br-Z1 through br-Z5) were found in close proximity to the br core region. mRNA of the br isoforms consisted of each of these isoform-specific domains alternatively spliced to the core region. An additional isoform was found that consisted of the br core region spliced to the br-Z1 and br-Z4 zinc-finger domains with an intron between them.