Protein tandem repeats

Common examples of protein tandem repeat structures: the WD40 repeat domain of beta-TrCP (green), leucine-rich repeat domain of TLR2 (red), armadillo repeat domain of beta-catenin (blue), ankyrin repeat domain of ANKRA2 (orange), kelch repeat domain of Keap1 (yellow) and HEAT repeat domain of a PP2A regulatory subunit R1a (magenta).

An array of protein tandem repeats is defined as several (at least two) adjacent copies having the same or similar sequence motifs. These periodic sequences are generated by internal duplications in both coding and non-coding genomic sequences. Repetitive units of protein tandem repeats are considerably diverse, ranging from the repetition of a single amino acid to domains of 100 or more residues.[1][2]

Schematic representation of tandem repeat sequence.
  1. ^ Heringa J (June 1998). "Detection of internal repeats: how common are they?". Current Opinion in Structural Biology. 8 (3): 338–45. doi:10.1016/s0959-440x(98)80068-7. PMID 9666330.
  2. ^ Andrade MA, Ponting CP, Gibson TJ, Bork P (May 2000). "Homology-based method for identification of protein repeats using statistical significance estimates". Journal of Molecular Biology. 298 (3): 521–37. doi:10.1006/jmbi.2000.3684. PMID 10772867.