Data di Pubblicazione:
1999
Citazione:
NF-Y histone fold α1 helices help impart CCAAT specificity / K. Zemzoumi, M. Frontini, M. Bellorini, R. Mantovani. - In: JOURNAL OF MOLECULAR BIOLOGY. - ISSN 0022-2836. - 286:2(1999 Feb 19), pp. 327-337.
Abstract:
NF-Y is a conserved trimeric transcriptional activator with an extremely high specificity for CCAAT boxes. The NF-YB and NF-YC subunits have histone fold motifs with a high degree of homology to NC2α/β, a TBP-binding repressor. The histone fold is composed of three α helices, α1, α2, α3, separated by short loops. Structural data on core histones showed that α1 are involved in DNA-binding. To understand the molecular basis of NF-Y sequence-specificity, we constructed deletion and swapping mutants, in which the α1 of NC2 and archeal HMfB, a bona fide histonic protein, was placed in NF-YB and NF-YC. Our analysis indicates that (i) subunit interactions are normal; (ii) NF-YB-NF-YC and NC2α/β do not form heterodimers and NC2 cannot associate NF-YA. (iii) None of the NF-Y swaps can complex with TBP on a TATA box. (iv) Specific residues, R47 and K49 in NF-YC and N61 in NF-YB, are crucial for CCAAT-binding. We conclude that specificity of the NF-Y trimer is not due to NF-YA only, but stems in part from the contribution of the histone fold α1, particularly that of NF-YB.
Tipologia IRIS:
01 - Articolo su periodico
Keywords:
Protein Structure, Secondary ; Regulatory Sequences, Nucleic Acid ; Amino Acid Sequence ; Archaea ; Bacterial Proteins ; Binding Sites ; CCAAT-Enhancer-Binding Proteins ; DNA ; DNA-Binding Proteins ; Dimerization ; Histones ; Molecular Sequence Data ; Mutagenesis, Site-Directed ; Phosphoproteins ; Protein Binding ; Recombinant Fusion Proteins ; Sequence Deletion ; Substrate Specificity ; Transcription Factors
Elenco autori:
K. Zemzoumi, M. Frontini, M. Bellorini, R. Mantovani
Link alla scheda completa: