Fig. 9. MAX2 encodes an F-box leucine-rich repeat protein. (A) Map-based cloning of the MAX2 gene. (Top) The markers flanking MAX2 that were used to screen for recombinants (m429, BIO2) and the closest flanking markers (F14N22-L, F7D19-H) that were located 57 kb apart on two overlapping BAC clones. The number of recombinant individuals, in a mapping population of 1300 plants, is given for each marker. (Bottom) The region between the closest flanking markers is enlarged to show the localisation of the PCR products for both markers (grey bars), the predicted gene structure (arrows), and the BAC subclones tested for mutant rescue (black and white bars). Mutant rescue by clones a and b identified F14N22.11 as the MAX2 gene. (B) The predicted MAX2 protein sequence contains an F-box motif (underlined) and imperfect leucine-rich repeats (LRR). Positions with similar amino acids in several repeats are shaded. Amino acids affected by the max2-1 and max2-2 mutations are boxed and the predicted changes are shown. (C) Alignment of the predicted MAX2 F-box motif with a translation of the corresponding region found in two partial Medicago truncatula ESTs homologous to MAX2 (AL369069, BE325112), and with the F-boxes of other Arabidopsis proteins. A general F-box consensus (Patton et al., 1998) is given above the MAX2 sequence and the residues of MAX2 that match this consensus are marked (*). The second column shows the classification of predicted Arabidopsis F-box proteins used by Xiao and Jang (Xiao and Jang, 2000).
