Figure 4.

Amino acid sequence alignment of His protein kinase transmitter (A) and receiver (B) domains of His protein kinases and related proteins in Arabidopsis. Sequences were aligned by the Clustal X program. Conserved amino acids are highlighted. Black and gray backgrounds indicate percentage of amino acid similarity: black, at least 75%; darker gray, 50%; and lighter gray, 25%. Amino acid similarity groups are: D, N; E, Q; S, T; K, R; F, Y, and W; and L, I, V, and M. Conserved motifs are indicated above the alignment. The numbers indicate the amino acid gaps between the motifs.