Solution Structures of Two CCHC Zinc Fingers from the FOG Family Protein
U-shaped that Mediate Protein-Protein Interactions

ninth zinc-finger domain of the u-shaped transcription factor

Information obtained from PDB's Chemical Component Dictionary
at http://wwpdb-remediation.rutgers.edu/downloads.html
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Solution structures of two CCHC zinc fingers from the FOG family protein U-shaped that mediate protein-protein interactions.

BACKGROUND: Zinc finger domains have traditionally been regarded as
sequence-specific DNA binding motifs. However, recent evidence indicates that
many zinc fingers mediate specific protein-protein interactions. For instance,
several zinc fingers from FOG family proteins have been shown to interact with
the N-terminal zinc finger of GATA-1. RESULTS: We have used NMR spectroscopy to
determine the first structures of two FOG family zinc fingers that are involved
in protein-protein interactions: fingers 1 and 9 from U-shaped. These fingers
resemble classical TFIIIA-like zinc fingers, with the exception of an unusual
extended portion of the polypeptide backbone prior to the fourth zinc ligand.
[15N,(1)H]-HSQC titrations have been used to define the GATA binding surface of
USH-F1, and comparison with other FOG family proteins indicates that the
recognition mechanism is conserved across species. The surface of FOG-type
fingers that interacts with GATA-1 overlaps substantially with the surface
through which classical fingers typically recognize DNA. This suggests that
these fingers could not contact both GATA and DNA simultaneously. In addition,
results from NMR, gel filtration, and sedimentation equilibrium experiments
suggest that the interactions are of moderate affinity. CONCLUSIONS: Our
results demonstrate unequivocally that zinc fingers comprising the classical
betabetaalpha fold are capable of mediating specific contacts between proteins.
The existence of this alternative function has implications for the prediction
of protein function from sequence data and for the evolution of protein
function.

Liew, C.K., Kowalski, K., Fox, A.H., Newton, A.,
Sharpe, B.K., Crossley, M., and Mackay, J.P.
Solution Structures of Two CCHC Zinc Fingers from
the FOG Family Protein U-shaped that Mediate
Protein-Protein Interactions.
Structure, 8, 1157-1166 (2000).

Solution Structure Of The Ninth Zinc-Finger Domain Of The U- Shaped Transcription Factor

molecular dynamics simulated annealing torsion angle dynamics