Characterization of early, chitin-induced gene expression in Arabidopsis.
Three genes (i.e., a zinc finger protein, a lectin-like protein, and AtMPK3), previously shown to respond to chitin elicitation in microarray experiments, were used to examine the response of Arabidopsis spp. to chitin addition. Maximum induction for all three genes was found upon addition of crab-shell chitin at 100 mg per liter. Threefold induction was found with a chitin concentration as low as 10(-4) mg per liter. The specificity of this response was examined using purified chitin oligomers (degree of polymerization = 2 to 8). The larger chitin oligomers (hexamer to octamer), were most effective in inducing expression of the three genes assayed. Gene induction was observed after the addition of 1 nM chitin octamer. The protein kinase inhibitors staurosporine and K252a effectively suppressed chitin-induced gene expression, while the protein phosphatase inhibitors calyculin A and okadaic acid induced the accumulation of mRNA in the absence of chitin. The phosphorylation event necessary for transmission of the chitin signal was completed within the first 20 min of chitin addition. The level of chitin-induced gene expression of the lectin-like protein and AtMPK3 was not significantly changed in mutants blocked in the jasmonic acid (JA, jar1)-, ethylene (ein2)-, or salicylic acid (SA, pad4, npr1, and eds5)-dependent pathway. In contrast, expression of mRNA for the zinc finger protein was reduced in the mutants affected in the JA- or SA-dependent pathway.
Zhang
Bing
B
Center for Legume Research, Department of Microbiology, University of Tennessee, Knoxville 37996-0845, USA.
Ramonell
Katrina
K
Somerville
Shauna
S
Stacey
Gary
G
D017360:Arabidopsis / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics; D002227:Carbazoles / Q000494:pharmacology; D002686:Chitin / Q000737:chemistry / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D026121:Indole Alkaloids; D037102:Lectins / Q000235:genetics; D008387:Marine Toxins; D020929:Mitogen-Activated Protein Kinase Kinases / Q000235:genetics; D019319:Okadaic Acid / Q000494:pharmacology; D009844:Oligosaccharides / Q000737:chemistry / Q000494:pharmacology; D010080:Oxazoles / Q000494:pharmacology; D010766:Phosphorylation / Q000187:drug effects; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D019311:Staurosporine / Q000494:pharmacology; D015533:Transcriptional Activation; D016335:Zinc Fingers / Q000235:genetics
D029681:Arabidopsis Proteins; D002227:Carbazoles; D004791:Enzyme Inhibitors; D026121:Indole Alkaloids; D037102:Lectins; D008387:Marine Toxins; D009844:Oligosaccharides; D010080:Oxazoles; D010940:Plant Proteins; D012333:RNA, Messenger; D002686:Chitin; D019319:Okadaic Acid; C059041:calyculin A; C049985:staurosporine aglycone; C458516:AtMPK3 protein, Arabidopsis; D020929:Mitogen-Activated Protein Kinase Kinases; D019311:Staurosporine