Fig. 2. Map-based cloning and structure of the ALE2 gene. (A) Map position of the ALE2 gene on chromosome 2. The fractions shown indicate the number of recombinant chromosomes divided by the total number of chromosomes scored for each marker. The 55 kb region between the closest recombination points is indicated as a gray bar. (B) Structure of the ALE2 gene and the positions of mutations. Coding regions and untranslated regions are shown by black and white boxes, respectively. Introns are shown by horizontal bars. The length of each segment is indicated in bp. (C) Predicted sequence of the ALE2 protein. Two hydrophobic regions and a kinase domain are indicated by underlining and double underlining, respectively. Mutated amino acid residues in the ale2-1 allele and sites of T-DNA insertion in the ale2-2 allele relative to the wild-type amino acid sequence are indicated. (D) Comparison of the amino acid sequences of the putative extracellular region of ALE2 and the predicted sequences of other proteins. Clusters of basic amino acid residues are boxed. Positions of conserved cysteine residues are indicated by asterisks.