Solution structures of two zinc-finger domains from SWI5 obtained using two-dimensional 1H nuclear magnetic resonance spectroscopy. A zinc-finger structure with a third strand of beta-sheet.
This paper describes the detailed three-dimensional structures of two zinc-finger domains from the yeast transcription factor SWI5, calculated using the results of the n.m.r. experiments described in the accompanying paper. The structure of finger 2 is essentially similar to those previously obtained by others for isolated, synthetic single zinc-finger domains in solution, and for the three zinc-finger peptide Zif268 in its crystalline complex with DNA. The N-terminal half of the sequence forms a two-stranded, irregular beta-sheet containing both of the metal-binding cysteine residues, while the remainder of the structure forms a helix. Approximately the first half of this helix is alpha-helical, whereas the C-terminal portion, including the two metal-binding histidine residues, is 3(10) helical. Four invariant hydrophobic residues form a core to the structure. In contrast to all previously described structures of zinc-finger domains, finger 1 has an additional strand in the beta-sheet, formed by residues N-terminal to the formal start of the finger motif. This additional strand plays a role in stabilising the folded form of finger 1, since a two-finger peptide lacking the N-terminal residues showed folded structure in finger 2 but not in finger 1.
Neuhaus
D
D
MRC Laboratory of Molecular Biology, Cambridge, England.
Nakaseko
Y
Y
Schwabe
J W
JW
Klug
A
A
D000595:Amino Acid Sequence; D018797:Cell Cycle Proteins; D003198:Computer Simulation; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D029701:Saccharomyces cerevisiae Proteins; D012996:Solutions; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism; D016335:Zinc Fingers
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C080218:SWI5 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D012996:Solutions; D014157:Transcription Factors; D004247:DNA