Journal Article

Structural Basis for the Oligomerization of the MADS Domain Transcription Factor SEPALLATA3 in Arabidopsis

Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Hart, Darren J, European Molecular Biology Laboratory, Acajjaoui, Samira, Puranik, Sriharsha, Dumas, Renaud, Vial, Anthony, Unit for Virus Host-Cell Interactions, Theissen, Guenter, Parcy, François, Conn, Vanessa, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Conn, Simon, European Synchrotron Radiation Facility (ESRF), Integrated Structural Biology Grenoble, Unit of Virus Host Cell Interactions, Brown, Elizabeth, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ANR-10-INBS-0005, FRISBI,Infrastructure Française pour la Biologie Structurale Intégrée, Laboratoire de physiologie cellulaire végétale (LPCV), Silva, Catarina S., Departement Genetique, Struct Biol Grp, Melzer, Rainer, Nanao, Max, Marcellin, Romain, Zubieta, Chloe, Costa, Luca

2014

Overview

In plants, MADS domain transcription factors act as central regulators of diverse developmental pathways. In Arabidopsis thaliana, one of the most central members of this family is SEPALLATA3 ( SEP3), which is involved in many aspects of plant reproduction, including floralmeristem and floral organ development. SEP3 has been shown to form homo and heterooligomeric complexes with other MADS domain transcription factors through its intervening ( I) and keratin-like ( K) domains. SEP3 function depends on its ability to form specific protein-protein complexes; however, the atomic level determinants of oligomerization are poorly understood. Here, we report the 2.5 angstrom crystal structure of a small portion of the intervening and the complete keratin-like domain of SEP3. The domains form two amphipathic alpha helices separated by a rigid kink, which prevents intramolecular association and presents separate dimerization and tetramerization interfaces comprising predominantly hydrophobic patches. Mutations to the tetramerization interface demonstrate the importance of highly conserved hydrophobic residues for tetramer stability. Atomic force microscopy was used to show SEP3-DNA interactions and the role of oligomerization in DNA binding and conformation. Based on these data, the oligomerization patterns of the larger family of MADS domain transcription factors can be predicted and manipulated based on the primary sequence.

• Publisher: American Society of Plant Biologists (ASPB),CCSD,American Society of Plant Biologists
• Subject: Amino Acid Sequence / Arabidopsis / Arabidopsis - metabolism / Arabidopsis Proteins - chemistry / Arabidopsis Proteins - metabolism / Arabidopsis thaliana / Chromatography, Gel / Crystallography, X-Ray / Dimerization / Dimers / DNA / DNA, Plant - metabolism / flowering / Gels / Genes / Homeodomain Proteins - chemistry / Homeodomain Proteins - metabolism / Life Sciences / MADS Domain Proteins - chemistry / MADS Domain Proteins - metabolism / Microscopy, Atomic Force / Models, Molecular / Molecular Sequence Data / Monomers / Mutant Proteins - chemistry / oligomerization / Plant cells / Plants / Promoter Regions, Genetic - genetics / Protein Binding / Protein Multimerization / Protein Structure, Tertiary / Proteins / Structure-Activity Relationship / Transcription factors / Transcription Factors - chemistry / Transcription Factors - metabolism / X-ray diffraction
• ISBN: 0003459197000