Crystal Structure of the Arabidopsis thaliana L1L/NF-YC3 Histone-fold Dimer Reveals Specificities of the LEC1 Family of NF-Y Subunits in Plants

Abstract

The NF-Y transcription factor is a heterotrimer formed by evolutionarily conserved subunits: NF-YA, NF-YB, and NF-YC. NF-YB and NF-YC harbor a histone fold domain (HFD), structurally similar to that of nucleosome core histones, and form a tight dimer (Romier et al., 2003). NF-YA binds to the NF-YB/NF-YC dimer and provides exquisite sequence specificity for recognizing and binding the CCAAT box (Huber et al., 2012; Nardini et al., 2013), an important DNA regulatory element of all eukaryotes (Dolfini et al., 2009).