NINJA connects the co-repressor TOPLESS to jasmonate signalling

• Published in: Nature (London) 2010-04, Vol.464 (7289), p.788-791
• Main Authors: Goossens, Alain, Pauwels, Laurens, Barbero, Gemma Fernández, Geerinck, Jan, Tilleman, Sofie, Grunewald, Wim, Pérez, Amparo Cuéllar, Chico, José Manuel, Bossche, Robin Vanden, Sewell, Jared, Gil, Eduardo, García-Casado, Gloria, Witters, Erwin, Inzé, Dirk, Long, Jeff A, De Jaeger, Geert, Solano, Roberto
• Format: Article
• Language: English
• Subjects: 631/208/200; 631/449/1741/2671; 631/45/612/822; 631/80/86; Adaptors; Arabidopsis - cytology; Arabidopsis - drug effects; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Arrays; Cellular signal transduction; Cyclopentanes - antagonists & inhibitors; Cyclopentanes - pharmacology; Ear; Gene expression; Gene Expression Profiling; Gene Expression Regulation, Plant; Genetic aspects; Humanities and Social Sciences; ISO standards; letter; Mass spectrometry; Models, Biological; multidisciplinary; Oxylipins - antagonists & inhibitors; Oxylipins - pharmacology; Perception; Physiological aspects; Plant genetics; Plants, Genetically Modified; Protein Binding; Proteins; Regulators; Repressor proteins; Repressor Proteins - genetics; Repressor Proteins - metabolism; Science; Science (multidisciplinary); Signal transduction; Signal Transduction - drug effects; Signalling; Two-Hybrid System Techniques
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/nature08854

Jasmonoyl-isoleucine (JA-Ile) is a plant hormone that regulates a broad array of plant defence and developmental processes. JA-Ile-responsive gene expression is regulated by the transcriptional activator MYC2 that interacts physically with the jasmonate ZIM-domain (JAZ) repressor proteins. On perception of JA-Ile, JAZ proteins are degraded and JA-Ile-dependent gene expression is activated. The molecular mechanisms by which JAZ proteins repress gene expression remain unknown. Here we show that the Arabidopsis JAZ proteins recruit the Groucho/Tup1-type co-repressor TOPLESS (TPL) and TPL-related proteins (TPRs) through a previously uncharacterized adaptor protein, designated Novel Interactor of JAZ (NINJA). NINJA acts as a transcriptional repressor whose activity is mediated by a functional TPL-binding EAR repression motif. Accordingly, both NINJA and TPL proteins function as negative regulators of jasmonate responses. Our results point to TPL proteins as general co-repressors that affect multiple signalling pathways through the interaction with specific adaptor proteins. This new insight reveals how stress-related and growth-related signalling cascades use common molecular mechanisms to regulate gene expression in plants.