NF-Y Transcription Factor Sandbox
From Proteopedia
Contents |
Protein Function
NF-Y is a transcription factor (TF) binding helper, and is an important protein involved in histone posttranslational modifications (PTMs). These PTMs aid in regions of the DNA that are destined to be transcribed. NF-Y is also involved in recruiting enzymes responsible for acetylations on active promoters. Furthermore, NF-Y is a sequence-specific TF. It is possible that NF-Y and other sequence-specific TFs determine histone modifications on promoters.
Protein Structure
NF-Y transcription factor consists of , , and subunits. NF-YA subunit contains two α-helices, NF-YB subunit contains four α-helices and two β-sheets, and NF-YC subunit contains three α-helices and two β-sheets. The NF-YB and NF-YC subunits each contain a histone fold motif and form a NF-YB/NF-YC heterodimer[1]. One of the two α helices of the NF-YA subunit, the N terminal , interacts with NF-YB/NF-YC heterodimer resulting in a heterotrimer. The NF-Y heterotrimer is stabilized by ionic interactions, interactions between the backbone atoms of residues, and hydrophobic residues. Stabilizing ionic interactions occur between Asn239(NF-YA) with Asp109(NF-YC) and Asp112(NF-YC)[2]. Residue backbone interactions occur between Leu123(NF-YB) with Phe113(NF-YC), Arg245(NF-YA) with Glu98(NF-YB) and Glu101(NF-YB), Arg249(NF-YA) with Glu90(NF-YB), and Arg250(NF-YA) with Asp116(NF-YC)[2]. Hydrophobic residues that contribute to the stabilization of the NF-Y heterotrimer are only located at NF-YA and NF-YB subunits at residues Ile246(NF-YA), Phe94(NF-YB), and Ile115(NF-YB)[2]. The NF-Y heterotrimer is also stabilized by the segment through intramolecular interactions of NF-YA residues on the main chain and side chain. Along with stabilization, the A1A2 linker provides the flexibility needed to direct the NF-YA chain toward DNA[2].
Interaction With DNA
The C terminal of the NF-YA subunit inserts deep into the minor groove of DNA. NF-YA A2 helix binds to the box and causes the minor groove to widen at the CCAAT box. An important residue in the catalytic site is
References
- ↑ Xiao J, Zhou Y, Lai H, Lei S, Chi LH, Mo X. Transcription Factor NF-Y Is a Functional Regulator of the Transcription of Core Clock Gene Bmal1. J Biol Chem. 2013 Nov 1;288(44):31930-6. doi: 10.1074/jbc.M113.507038. Epub 2013 , Sep 12. PMID:24030830 doi:http://dx.doi.org/10.1074/jbc.M113.507038
- ↑ 2.0 2.1 2.2 2.3 Nardini M, Gnesutta N, Donati G, Gatta R, Forni C, Fossati A, Vonrhein C, Moras D, Romier C, Bolognesi M, Mantovani R. Sequence-Specific Transcription Factor NF-Y Displays Histone-like DNA Binding and H2B-like Ubiquitination. Cell. 2013 Jan 17;152(1-2):132-43. doi: 10.1016/j.cell.2012.11.047. PMID:23332751 doi:http://dx.doi.org/10.1016/j.cell.2012.11.047