Molecular dynamics simulations reveal the disparity in specific recognition of GCC-box by AtERFs transcription factors super family in Arabidopsis

Arabidopsis ethylene responsive element binding factors (AtERFs) form a transcription factor super family. While the functions of most AtERFs are unknown, a number of AtERFs appear to be involved in regulation of stress-related genes through their DNA binding domains (DBD), namely ERF domains, which recognize a consensus motif GCC-box at the regulatory region. In this study, molecular dynamics simulations were performed on the four ERF domain-GCC-box complexes, AtERF1, AtERF4, AtEBP and CFBF1, to determine disparity in specific binding to the GCC-box by the AtERFs. Our results suggested that three amino acid residues Arg29, GIu39 and Arg41, played a vital role in direct readout of DNA. The position of the consensus sequence GCCGCC has an intrinsic disparity on binding with ERF domains. The third C, fourth G and the last C in the GCC motif was compulsory for recognition by ERF domains. Our results provide structural evidence for a sequence-dependent recognition mechanism for AtERFs. Copyright (C) 2009 John Wiley & Sons, Ltd.