Induction of apoptotic cell death leads to the development of bacterial rot caused by Pseudomonas cichorii.
Pseudomonas cichorii is the major causal agent of bacterial rot of lettuce. Collapse and browning symptoms were observed in lettuce leaf tissue from 15 to 24 h after inoculation (HAI) with P. cichorii; superoxide anion generation was detected at 1 to 6 HAI; and cell death was induced at 6 HAI, reaching a maximum at approximately 9 and 12 HAI. Heterochromatin condensation and DNA laddering also were observed within 3 HAI. Pharmacological studies showed that induction of cell death and DNA laddering was closely associated with de novo protein synthesis, protein kinase, intracellular reactive oxygen species, DNase, serine protease, and caspase III-like protease. Moreover, chemicals, which inhibited the induction of cell death and DNA laddering, also suppressed the development of disease symptoms. These results suggest that apoptotic cell death might be closely associated with the development of bacterial rot caused by P. cichorii.
Kiba
Akinori
A
Laboratory of Plant Pathology and Biotechnology, Faculty of Agriculture, Kochi University, Nankoku, 783-8502 Japan. akiba@cc.kochi-u.ac.jp
Sangawa
Yasutaka
Y
Ohnishi
Kouhei
K
Yao
Nan
N
Park
Pyoyun
P
Nakayashiki
Hitoshi
H
Tosa
Yukio
Y
Mayama
Shigeyuki
S
Hikichi
Yasufumi
Y
D000838:Anions / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D018929:Cell Culture Techniques; D018744:DNA, Plant / Q000378:metabolism; D003851:Deoxyribonucleases / Q000037:antagonists & inhibitors; D016166:Free Radical Scavengers / Q000378:metabolism; D018545:Lactuca / Q000187:drug effects / Q000382:microbiology / Q000648:ultrastructure; D010447:Peptide Hydrolases / Q000378:metabolism; D009195:Peroxidase / Q000378:metabolism; D010641:Phenotype; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves / Q000033:anatomy & histology / Q000187:drug effects / Q000382:microbiology / Q000648:ultrastructure; D011133:Polysaccharide-Lyases / Q000378:metabolism; D011494:Protein Kinases / Q000378:metabolism; D011549:Pseudomonas / Q000472:pathogenicity*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism; D013997:Time Factors
D000838:Anions; D018744:DNA, Plant; D016166:Free Radical Scavengers; D017382:Reactive Oxygen Species; D013481:Superoxides; D009195:Peroxidase; D011494:Protein Kinases; D003851:Deoxyribonucleases; D010447:Peptide Hydrolases; D011133:Polysaccharide-Lyases; C023911:pectate lyase