These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: The second zinc-finger domain of poly(ADP-ribose) polymerase determines specificity for single-stranded breaks in DNA.
    Author: Gradwohl G, Ménissier de Murcia JM, Molinete M, Simonin F, Koken M, Hoeijmakers JH, de Murcia G.
    Journal: Proc Natl Acad Sci U S A; 1990 Apr; 87(8):2990-4. PubMed ID: 2109322.
    Abstract:
    Poly(ADP-ribose) polymerase (EC 2.4.2.30) is a zinc-binding protein that specifically binds to a DNA strand break in a zinc-dependent manner. We describe here the cloning and expression in Escherichia coli of a cDNA fragment encoding the two putative zinc fingers (FI and FII) domain of the human poly(ADP-ribose) polymerase. Using site-directed mutagenesis, we identified the amino acids involved in metal coordination and analyzed the consequence of altering the proposed zinc-finger structures on DNA binding. Disruption of the metal binding ability of the second zinc finger, FII, dramatically reduced target DNA binding. In contrast, when the postulated Zn(II) ligands of FI were mutated, the DNA binding activity was only slightly affected. DNase I protection studies showed that the FII is involved in the specific recognition of a DNA strand break. These results demonstrate that poly(ADP-ribose) polymerase contains a type of zinc finger that differs from previously recognized classes in terms of both structure and function.
    [Abstract] [Full Text] [Related] [New Search]