Direct ETTIN-auxin interaction controls chromatin states in gynoecium development

eLife

Stefan Kepinski¹  Sigurd Ramans Harborough¹  André Kuhn²  Bhavani Natarajan²  Heather M McLaughlin²  Lars Østergaard²  Jiří Friml³  Inge Verstraeten³ 

[1] Centre for Plant Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, United Kingdom;Department of Crop Genetics, John Innes Centre, Norwich Research Park, Norwich, United Kingdom;Institute of Science and Technology, Klosterneuburg, Austria;

关键词: Auxin;    ETTIN;    Chromatin;    gene expression;    gynoecium;    histone modification;    A. thaliana;   

DOI  :  10.7554/eLife.51787

来源: publisher

【 摘 要 】

Hormonal signalling in animals often involves direct transcription factor-hormone interactions that modulate gene expression. In contrast, plant hormone signalling is most commonly based on de-repression via the degradation of transcriptional repressors. Recently, we uncovered a non-canonical signalling mechanism for the plant hormone auxin whereby auxin directly affects the activity of the atypical auxin response factor (ARF), ETTIN towards target genes without the requirement for protein degradation. Here we show that ETTIN directly binds auxin, leading to dissociation from co-repressor proteins of the TOPLESS/TOPLESS-RELATED family followed by histone acetylation and induction of gene expression. This mechanism is reminiscent of animal hormone signalling as it affects the activity towards regulation of target genes and provides the first example of a DNA-bound hormone receptor in plants. Whilst auxin affects canonical ARFs indirectly by facilitating degradation of Aux/IAA repressors, direct ETTIN-auxin interactions allow switching between repressive and de-repressive chromatin states in an instantly-reversible manner.

【 授权许可】

CC BY