PROSITE documentation PDOC50088
Ankyrin repeat and ankyrin repeat region profiles


Ankyrin repeats (ANK) are tandemly repeated modules of about 33 amino acids. They occur in a large number of functionally diverse proteins mainly from eukaryotes. The few known examples from prokaryotes and viruses may be the result of horizontal gene transfers [1].

Many ankyrin repeat regions are known to function as protein-protein interaction domains.

The conserved fold of the ankyrin repeat unit is known from several crystal and solution structures, e.g. from:

  • p53-binding protein 53BP2 [2],
  • Cyclin-dependent kinase inhibitor p19Ink4d [3],
  • Transcriptional regulator GABP-β [4],
  • NF-kappaB inhibitory protein IkB-α [5].

It has been described as an L-shaped structure consisting of a β-hairpin and two α-helices [2].

Two profiles were developed for this module, the first one picks up ANK repeats while the second profile is 'circular' and will thus detect a region containing adjacent ANK repeats.

Last update:

December 2001 / First entry.


Technical section

PROSITE methods (with tools and information) covered by this documentation:

ANK_REPEAT, PS50088; Ankyrin repeat profile  (MATRIX)

ANK_REP_REGION, PS50297; Ankyrin repeat region circular profile  (MATRIX)


1AuthorsBork P.
TitleHundreds of ankyrin-like repeats in functionally diverse proteins: mobile modules that cross phyla horizontally?
SourceProteins 17:363-374(1993).
PubMed ID8108379

2AuthorsGorina S. Pavletich N.P.
TitleStructure of the p53 tumor suppressor bound to the ankyrin and SH3 domains of 53BP2.
SourceScience 274:1001-1005(1996).
PubMed ID8875926

3AuthorsLuh F.Y. Archer S.J. Domaille P.J. Smith B.O. Owen D. Brotherton D.H. Raine A.R. Xu X. Brizuela L. Brenner S.L. Laue E.D.
TitleStructure of the cyclin-dependent kinase inhibitor p19Ink4d.
SourceNature 389:999-1003(1997).
PubMed ID9353127

4AuthorsBatchelor A.H. Piper D.E. de la Brousse F.C. McKnight S.L. Wolberger C.
TitleThe structure of GABPalpha/beta: an ETS domain- ankyrin repeat heterodimer bound to DNA.
SourceScience 279:1037-1041(1998).
PubMed ID9461436

5AuthorsJacobs M.D. Harrison S.C.
TitleStructure of an IkappaBalpha/NF-kappaB complex.
SourceCell 95:749-758(1998).
PubMed ID9865693

PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see prosite_license.html.


View entry in original PROSITE document format
View entry in raw text format (no links)