Regulation of SOBIR1 accumulation and activation of defense responses in bir1-1 by specific components of ER quality control.
Receptor-like kinases play diverse roles in plant biology. Arabidopsis BAK1-INTERACTING RECEPTOR-LIKE KINASE 1 (BIR1) functions as a negative regulator of plant immunity. bir1-1 mutant plants display spontaneous cell death and constitutive defense responses that are dependent on SUPPRESSOR OF BIR1,1 (SOBIR1) and PHYTOALEXIN DEFICIENT4 (PAD4). Here we report that mutations in three components of ER quality control, CALRETICULIN3 (CRT3), ER-LOCALIZED DnaJ-LIKE PROTEIN 3b (ERdj3b) and STROMAL-DERIVED FACTOR-2 (SDF2), also suppress the spontaneous cell death and constitutive defense responses in bir1-1. Further analysis revealed that accumulation of the SOBIR1 protein is reduced in crt3-1 and erdj3b-1 mutant plants. These data suggest that ER quality control plays important roles in the biogenesis of SOBIR1, and is required for cell death and defense responses in bir1-1.
Department of Botany, University of British Columbia, Vancouver, BC, Canada, V6T 1Z4.
Tongjun
T
Sun
Qian
Q
Zhang
Minghui
M
Gao
Yuelin
Y
Zhang
D000483:Alleles; D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism*; D037282:Calreticulin / Q000378:metabolism; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism; D016923:Cell Death; D004721:Endoplasmic Reticulum / Q000502:physiology*; D050956:HSP40 Heat-Shock Proteins / Q000378:metabolism*; D010641:Phenotype; D057865:Plant Immunity; D011494:Protein Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D051192:Receptors, Pattern Recognition / Q000378:metabolism
D029681:Arabidopsis Proteins; D037282:Calreticulin; C000596011:ERdj3b protein, Arabidopsis; D050956:HSP40 Heat-Shock Proteins; D051192:Receptors, Pattern Recognition; C545107:SDF2 protein, Arabidopsis; C584706:calreticulin 3, Arabidopsis; D011494:Protein Kinases; C000593371:SOBIR protein, Arabidopsis; C570514:BIR1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases; D002265:Carboxylic Ester Hydrolases; C400766:PAD4 protein, Arabidopsis
CRT3; ER-quality control; Erdj3b; SDF2; SOBIR1; plant immunity