Identification of a Novel Jasmonate-Responsive Element in the AtJMT Promoter and Its Binding Protein for AtJMT Repression

Abstract

Jasmonates (JAs) are important regulators of plant biotic and abiotic stress responses and development. AtJMT in Arabidopsis thaliana and BcNTR1 in Brassica campestris encode jasmonic acid carboxyl methyltransferases, which catalyze methyl jasmonate (MeJA) biosynthesis and are involved in JA signaling. Their expression is induced by MeJA application. To understand its regulatory mechanism, here we define a novel JA-responsive cis-element (JARE), G(C)TCCTGA, in the AtJMT and BcNTR1 promoters, by promoter deletion analysis and Yeast 1-Hybrid (Y1H) assays; the JARE is distinct from other JA-responsive cis-elements previously reported. We also used Y1H screening to identify a trans-acting factor, AtBBD1, which binds to the JARE and interacts with AtJAZ1 and AtJAZ4. Knockout and overexpression analyses showed that AtBBD1 and its close homologue AtBBD2 are functionally redundant and act as negative regulators of AtJMT expression. However, AtBBD1 positively regulated the JA-responsive expression of JR2. Chromatin immunoprecipitation from knockout and overexpression plants revealed that repression of AtJMT is associated with reduced histone acetylation in the promoter region containing the JARE. These results show that AtBBD1 interacts with JAZ proteins, binds to the JARE and represses AtJMT expression.

Transcriptome Analysis Reveals Genes Commonly Induced by Botrytis cinerea Infection, Cold, Drought and Oxidative Stresses in Arabidopsis

“…One of the commonly induced genes was CORI3/JR2 , which encodes cystine lyase, an enzyme that generates an ET precursor. In another study, COR13 / JR2 transcript levels were elevated in response to the hemibiotrophic pathogen Pseudomonas syringae , wounding, and JA [59] – [61] . In Arabidopsis , the ABA-induced gene RD20 , which encodes a member of caleosin family, is also induced by drought and B. cinerea [62] .…”

Metatranscriptomic Analysis of Multiple Environmental Stresses Identifies RAP2.4 Gene Associated with Arabidopsis Immunity to Botrytis cinerea

“…S3, Supporting Information). The CORI3/JR2 gene encoding cystine lyase is an enzyme that generates an ET precursor, and has been previously reported to be induced by B. cinerea , cold, drought and oxidative stresses 10 , P. syringae 40 , wounding 46 and MeJA 47 . Arabidopsis RAP2.4d, a common repressed gene to all stresses in test, is a member of RAP2.4 (AP2/DREB-type TF) family, was down-regulated in response to cold, light and ET but up-regulated in response to oxidative stress, increased salt and drought 48,49 , suggesting a role of RAP2.4 to coordinately regulate multiple abiotic stress responses.…”

Isolation and functional characterization of the promoter of a DEAD-box helicasePsp68usingAgrobacterium-mediated transient assay

“…Although conserved similar sequence were observed in the promoter of many auxin responsive genes, 50,51 it remains need to be tested the functional significance of these conserved sequences. Jasmonates are another growth regulators 52 important for plant biotic and abiotic stress responses. [53][54][55] Either GCC or G-box elements are required for MeJA-inducible expression of different genes.…”