Figure 4
Hierarchical clustering analysis of amino acid hydropathy distributions within LRR domains of NLRs and TLRs. Color matrix shows values for first four moments (m0,..., m3; cf. Equation 1) of the hydropathy distribution over four LRR domain surfaces: inner (concave), N-terminal side, C-terminal side, and outer (convex). Red coloring corresponds to positive values of the moments, black to zero, and green to negative values. The measure of similarity between sequences of moment values of LRR surfaces is the Spearman's rank-order correlation coefficient, r S . The tree on the left is the result of hierarchical clustering of pairwise distances by the complete linkage method. Length of edges is proportional to distances, d S , between sequences of moment values and is defined as d S = 1 - r S . Grouping of LRR domains into clusters indicates overall similarity of their hydrophobicity distributions.