Figure 2.

Esi47 belongs to a unique subgroup of the plant NAK group protein kinases. The amino acid sequences of the catalytic domains of the protein kinases shown were compared by the CLUSTAL method (Higgins and Sharp, 1988). The kinase groups, according to Hardie (1999), are indicated in the right column. The kinases in the NAK group, except for ARSK1, which are the most similar proteins to Esi47, were determined by BLASTP search in the databases. The database accession numbers for the genes encoding the kinases are shown in brackets. The two disease-resistance related protein kinases, Pto (Martin et al., 1993) and Pti1 (Zhou et al., 1995), are from tomato; the SNF1-related protein kinase PKABA1 (Anderberg and Walker-Simmons, 1992) is from wheat; the rest, except for Esi47, are from Arabidopsis. RLK, Receptor-like kinase; LRR, Leu-rich repeat; PK, protein kinase, CDPK, Ca²⁺/calmodulin-dependent kinase; MAPK, mitogen-activated protein kinase; MAPKK, mitogen-activated protein kinase kinase.