Two novel RING-type ubiquitin ligases, RGLG3 and RGLG4, are essential for jasmonate-mediated responses in Arabidopsis.
Jasmonates (JAs) regulate various stress responses and development processes in plants, and the JA pathway is tightly controlled. In this study, we report the functional characterization of two novel RING-type ubiquitin ligases, RING DOMAIN LIGASE3 (RGLG3) and RGLG4, in modulating JA signaling. Both RGLG3 and RGLG4 possessed ubiquitin ligase activities and were widely distributed in Arabidopsis (Arabidopsis thaliana) tissues. Altered expression of RGLG3 and RGLG4 affected methyl JA-inhibited root growth and JA-inductive gene expression, which could be suppressed by the coronatine insensitive1 (coi1) mutant. rglg3 rglg4 also attenuated the inhibitory effect of JA-isoleucine-mimicking coronatine on root elongation, and consistently, rglg3 rglg4 was resistant to the coronatine-secreting pathogen Pseudomonas syringae pv tomato DC3000, suggesting that RGLG3 and RGLG4 acted in response to the coronatine and promoted JA-mediated pathogen susceptibility. In addition, rglg3 rglg4 repressed wound-stunted plant growth, wound-stimulated expression of JA-responsive genes, and wound-induced JA biosynthesis, indicating their roles in JA-dependent wound response. Furthermore, both RGLG3 and RGLG4 responded to methyl JA, P. syringae pv tomato DC3000, and wounding in a COI1-dependent manner. Taken together, these results indicate that the ubiquitin ligases RGLG3 and RGLG4 are essential upstream modulators of JA signaling in response to various stimuli.
State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, People's Republic of China.
Xu
X
Zhang
Qian
Q
Wu
Jiao
J
Ren
Wanqiang
W
Qian
Shanping
S
He
Kuowei
K
Huang
Xiangchun
X
Yu
Yin
Y
Gao
Ping
P
Huang
Chengcai
C
An
D000085:Acetates / Q000494:pharmacology*; D000596:Amino Acids / Q000378:metabolism; D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism; D003517:Cyclopentanes / Q000494:pharmacology*; D004789:Enzyme Activation; D025461:Feedback, Physiological; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D007192:Indenes / Q000378:metabolism; D054883:Oxylipins / Q000494:pharmacology*; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology; D057865:Plant Immunity; D018517:Plant Roots / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D044224:Pseudomonas syringae / Q000472:pathogenicity; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D054875:Ubiquitination
D000085:Acetates; D000596:Amino Acids; D029681:Arabidopsis Proteins; D001426:Bacterial Proteins; C112279:COI1 protein, Arabidopsis; D003517:Cyclopentanes; D007192:Indenes; D054883:Oxylipins; D011994:Recombinant Proteins; C058487:coronatine; C072239:methyl jasmonate; C572710:RGLG2 protein, Arabidopsis; D044767:Ubiquitin-Protein Ligases