IDENTIFICATION OF AMINO-ACID POLYMORPHISM WITHIN THE LEUCINE-ZIPPER MOTIF OF MOUSE TRANSCRIPTION FACTOR A1

Mouse transcription factor A1 (A1) is a mouse homologue of human E47, a ubiquitously expressed DNA-binding protein which contains a basic re gion, helix-loop-helix (HLH) and leucine zipper (LZ) motifs [Walker et al., Nucleic Acids Res. 18 (1990) 1159-1166]. Analyses of the nucleot ide (nt) sequences of A1 cDNAs isolated from various mouse strains rev ealed amino acid (aa) polymorphism in the highly conserved region with in the LZ motif. Interestingly, the location and pattern of aa deletio ns are identical to those previously described for the aa polymorphism within the human counterpart, E47 (E12) [Kamps et al., Cell 60 (1990) 547-555].