The membrane-anchored BOTRYTIS-INDUCED KINASE1 plays distinct roles in Arabidopsis resistance to necrotrophic and biotrophic pathogens.
Plant resistance to disease is controlled by the combination of defense response pathways that are activated depending on the nature of the pathogen. We identified the Arabidopsis thaliana BOTRYTIS-INDUCED KINASE1 (BIK1) gene that is transcriptionally regulated by Botrytis cinerea infection. Inactivation of BIK1 causes severe susceptibility to necrotrophic fungal pathogens but enhances resistance to a virulent strain of the bacterial pathogen Pseudomonas syringae pv tomato. The response to an avirulent bacterial strain is unchanged, limiting the role of BIK1 to basal defense rather than race-specific resistance. The jasmonate- and ethylene-regulated defense response, generally associated with resistance to necrotrophic fungi, is attenuated in the bik1 mutant based on the expression of the plant defensin PDF1.2 gene. bik1 mutants show altered root growth, producing more and longer root hairs, demonstrating that BIK1 is also required for normal plant growth and development. Whereas the pathogen responses of bik1 are mostly dependent on salicylic acid (SA) levels, the nondefense responses are independent of SA. BIK1 is membrane-localized, suggesting possible involvement in early stages of the recognition or transduction of pathogen response. Our data suggest that BIK1 modulates the signaling of cellular factors required for defense responses to pathogen infection and normal root hair growth, linking defense response regulation with that of growth and development.
Veronese
Paola
P
Department of Botany and Plant Pathology, Purdue University, West Lafayette, Indiana 47907-2054, USA.
Nakagami
Hirofumi
H
Bluhm
Burton
B
Abuqamar
Synan
S
Chen
Xi
X
Salmeron
John
J
Dietrich
Robert A
RA
Hirt
Heribert
H
Mengiste
Tesfaye
T
D000528:Alternaria / Q000472:pathogenicity; D000935:Antifungal Agents / Q000378:metabolism; D017360:Arabidopsis / Q000033:anatomy & histology / Q000235:genetics / Q000382:microbiology* / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D020171:Botrytis / Q000472:pathogenicity*; D016923:Cell Death / Q000502:physiology; D002462:Cell Membrane / Q000201:enzymology*; D006861:Hydrogen Peroxide / Q000378:metabolism; D016877:Oxidants / Q000378:metabolism; D010935:Plant Diseases / Q000235:genetics; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D020156:Salicylic Acid / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology
D000935:Antifungal Agents; D029681:Arabidopsis Proteins; D016877:Oxidants; D006861:Hydrogen Peroxide; C509522:BIK1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases; D020156:Salicylic Acid