Figure 5.

Mutations in the RxxxS Motif of ATL1 Eliminate EDR1-Mediated Suppression of ATL1-Induced Cell Death.

(A) Amino acid sequence alignment of ATL1 with its closest paralog in Arabidopsis, ATL16, and with its two closest homologs in rice (OsATL40 and OsATL42). Black and gray shading indicates conserved amino acids. Red boxes indicate conserved Arg and Ser residues that were mutagenized to Ala and/or Asp in the different ATL1 mutants.

(B) and (C) ATL1^S312D and ATL1^R308A/S312D do not induce cell death in N. benthamiana.

(D) to (F) ATL1^S312A-, ATL1^R308A-, and ATL1^R308A/S312A-induced cell death in N. benthamiana cannot be suppressed by coexpression with EDR1-sYFP. Ion leakage measurements are shown for each mutant. Error bars represent sd; n = 3. All ATL1 constructs were expressed using a 35S promoter, and EDR1 was expressed under a dexamethasone-inducible promoter. Photographs were taken 48 hpi of Agrobacterium. The entire experiment was repeated twice with similar results.