Zincfinger

From DrugPedia: A Wikipedia for Drug discovery

WHAT IS ZINC FINGER?

Configuration of a DNA-binding protein that resembles a finger with a base, usually cysteines and histidines, binding a zinc ion. Discovered in a transcription factor in Xenopus but present in a large number of different proteins.

Function: The DNA-binding motif is found as part of transcription regulatory proteins.

Structure: One of the most abundant DNA-binding motifs. Proteins may contain more than one finger in a single chain; each motif consists of 2 antiparallel beta-strands followed by by an alpha-helix. A single zinc ion is tetrahedrally coordinated by conserved histidine and cysteine residues, stabilising the motif.

Binding: Fingers bind to 3 base-pair subsites and specific contacts are mediated by amino acids in positions -1, 2, 3 and 6 relative to the start of the alpha-helix. Contacts mainly involve one strand of the DNA.Where proteins contain multiple fingers, each finger binds to adjacent subsites within a larger DNA recognition site thus allowing a relatively simple motif to specifically bind to a wide range of DNA sequences.

[edit] EXTERNAL LINKS

[1] (zinc finger consortium)

[2] (BI tools related to searching zinc fingers)