1chc
STRUCTURE OF THE C3HC4 DOMAIN BY 1H-NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY; A NEW STRUCTURAL CLASS OF ZINC-FINGER
Structural highlights
FunctionICP0_EHV1B Evades nuclear antiviral defenses triggered by dsDNA viruses. Acts during the initial stages of lytic infection and the reactivation of latent viral genome. Prevents the antiviral effect of nuclear bodies by degrading host PML and SP100. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedA recently identified sequence motif, referred to as "C3HC4" (also "RING finger" and "A Box") for its distinctive pattern of putative metal-binding residues, has been found in a wide range of proteins. In a previous paper we described the expression and purification of fragments encompassing this motif from the Vmw110 (IPC0) protein family. We showed that the equine herpes virus protein binds zinc ions and adopts a beta beta alpha beta fold. We now report the tertiary structure of this domain in solution, as determined by two-dimensional 1H-NMR An amphipathic alpha-helix lies along one surface of a triple-stranded beta-sheet. Four pairs of metal-binding residues sequester two zincs at distinct tetrahedral sites. The first and third pairs bind one metal ion, while the second and fourth pairs bind the other, forming an interleaved whole. The first and the fourth pairs are contained within two prominent, well-defined loops related by an approximate dyad symmetry. Conserved residues within the helix, sheet and loops contribute to a compact hydrophobic core. The region comprising the first two beta-strands and the alpha-helix has remarkable structural similarity with a TFIIIA type of zinc finger, even though the C3HC4 domain appears not to bind specifically to DNA or RNA. Using site-directed mutagenesis we demonstrate that exposed polar side-chains of the C3HC4 alpha-helix are essential for trans-activation of gene expression by an intact herpes virus regulatory protein. Structure of the C3HC4 domain by 1H-nuclear magnetic resonance spectroscopy. A new structural class of zinc-finger.,Barlow PN, Luisi B, Milner A, Elliott M, Everett R J Mol Biol. 1994 Mar 25;237(2):201-11. PMID:8126734[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||
