A D53 repression motif induces oligomerization of TOPLESS corepressors and promotes assembly of a corepressor-nucleosome complex.Ma, H., Duan, J., Ke, J., He, Y., Gu, X., Xu, T.H., Yu, H., Wang, Y., Brunzelle, J.S., Jiang, Y., Rothbart, S.B., Xu, H.E., Li, J., Melcher, K.
(2017) Sci Adv 3: e1601217-e1601217
- PubMed: 28630893
- DOI: 10.1126/sciadv.1601217
- Primary Citation of Related Structures:
- PubMed Abstract:
- Structural basis for recognition of diverse transcriptional repressors by the TOPLESS family of corepressors.
Ke, J.,Ma, H.,Gu, X.,Thelen, A.,Brunzelle, J.S.,Li, J.,Xu, H.E.,Melcher, K.
(2015) Sci Adv 1: e1500107
TOPLESS are tetrameric plant corepressors of the conserved Tup1/Groucho/TLE (transducin-like enhancer of split) family. We show that they interact through their TOPLESS domains (TPDs) with two functionally important ethylene response factor-associate ...
TOPLESS are tetrameric plant corepressors of the conserved Tup1/Groucho/TLE (transducin-like enhancer of split) family. We show that they interact through their TOPLESS domains (TPDs) with two functionally important ethylene response factor-associated amphiphilic repression (EAR) motifs of the rice strigolactone signaling repressor D53: the universally conserved EAR-3 and the monocot-specific EAR-2. We present the crystal structure of the monocot-specific EAR-2 peptide in complex with the TOPLESS-related protein 2 (TPR2) TPD, in which the EAR-2 motif binds the same TPD groove as jasmonate and auxin signaling repressors but makes additional contacts with a second TPD site to mediate TPD tetramer-tetramer interaction. We validated the functional relevance of the two TPD binding sites in reporter gene assays and in transgenic rice and demonstrate that EAR-2 binding induces TPD oligomerization. Moreover, we demonstrate that the TPD directly binds nucleosomes and the tails of histones H3 and H4. Higher-order assembly of TPD complexes induced by EAR-2 binding markedly stabilizes the nucleosome-TPD interaction. These results establish a new TPD-repressor binding mode that promotes TPD oligomerization and TPD-nucleosome interaction, thus illustrating the initial assembly of a repressor-corepressor-nucleosome complex.
Key Laboratory of Receptor Research, VARI-SIMM Center, Center for Structure and Function of Drug Targets, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, People's Republic of China.