The phosphorylatable Ser320 of NF‐YA is involved in DNA binding of the NF‐Y trimer. Issue 4 (27th December 2018)

• Record Type: Journal Article
• Authors: Bernardini, Andrea; Lorenzo, Mariangela; Nardini, Marco; Mantovani, Roberto; Gnesutta, Nerina
• Is Part Of: FASEB journal. Volume 33:Issue 4(2019)
• Page Start: 4790
• Page End: 4801
• Publication Date: 2018-12-27
• Subjects: transcription factor -- DNA‐protein interactions -- post‐translational modification -- cyclin‐dependent kinase -- histone‐fold domain; Biology -- Periodicals; Biology, Experimental -- Periodicals; 570
• DOI: 10.1096/fj.201801989R
• Languages: English
• ISSNs: 0892-6638

Abstract

ABSTRACT: Nuclear factor Y (NF‐Y) is a transcription factor trimer binding to the functionally important CCAAT box, present in promoters of growth‐promoting and cell cycle‐regulated genes. The regulatory nuclear factor YA (NF‐YA) subunit confers sequence‐specificity to the histone‐like nuclear factor YB/YC dimer. NF‐YA harbors 2 serines—Ser320 and Ser326—shown to be phosphorylated by cyclin‐dependent kinase 2. High‐throughput proteomics data indicate that they are phosphorylated in vivo . Specifically, Ser320 makes structural contacts with the DNA phosphate backbone; Ser320‐P is the major NF‐YA phosphorylation isoform following overexpression in HeLa cells, increasing upon mitotic arrest. EMSA with recombinant Ala and Glu mutants confirm a role of Ser320, but not Ser326, in stabilization of DNA binding. Transactivation assays of the CCAAT‐dependent MDR1 and RHOB promoters show loss in transcription function for Ser320Glu and Ser320Ala NF‐YA mutants. Phylogenetic analysis of NF‐YA proteins indicates that Ser320 is indeed evolutionarily conserved. We conclude that phosphorylation of this residue belongs to the core mechanisms of DNA‐binding control, possibly driven by the necessity to unfasten binding of or to evict NF‐Y from CCAAT sites under specific conditions of growth regulation.—Bernardini, A., Lorenzo, M., Nardini, M., Mantovani, R., Gnesutta, N. The phosphorylatable Ser320 of NF‐YA is involved in DNA binding of the NF‐Y trimer. FASEB J. 33, 4790–4801 (2019). www.fasebj.org