|PROSITE documentation PDOC50005 [for PROSITE entry PS50293]|
The tetratrico peptide repeat (TPRs)  is a degenerate 34-amino acid repeated motif that is widespread among all organisms. In the cell, TPR containing proteins are localized in a variety of subcellular compartment, including the nucleus, the cytoplasm and mitochondria . Processes involving TPR proteins include cell-cycle control, transcription repression, stress response, protein kinase inhibition, mitochondrial and peroxisomal protein transport and neurogenesis. TPR repeats mediate protein-protein interactions and the assembly of multiprotein complexes. The smallest functional unit that is widely used appears to be three tandem-TPR motifs .
Many 3D structures of TPR domains have been solved (see for example <PDB:1A17>) . A single TPR contains two antiparallel α helices which pack into an open structure  such that tandem arrays of TPR motifs generate a right-handed helical structure with an amphipathic channel that might accommodate the complementary region of a target protein. An additional capping helix at the C-terminus is present in almost all TPR structures solved to date. This helix could be essential for the solubility or stability of these isolated domains. The consensus sequence of a TPR is defined by a pattern of small and large hydrophobic amino acids. Turn-positions, both between the two helices of a single TPR and between the two adjacent TPRs, show conservation of helix-breaking residues .
Some of the proteins containing TPR repeats are listed below:
Two profiles were developed for this module, the first one picks up TPR repeat units while the second profile is 'circular' and will thus detects a region containing adjacent TPR repeats.Last update:
January 2004 / First entry.
PROSITE methods (with tools and information) covered by this documentation:
|1||Authors||Sikorski R.S., Boguski M.S., Goebl M., Hieter P.|
|Title||A repeating amino acid motif in CDC23 defines a family of proteins and a new relationship among genes required for mitosis and RNA synthesis.|
|2||Authors||Goebl M., Yanagida M.|
|Title||The TPR snap helix: a novel protein repeat motif from mitosis to transcription.|
|Source||Trends Biochem. Sci. 16:173-177(1991).|
|3||Authors||Lamb J.R., Tugendreich S., Hieter P.|
|Title||Tetratrico peptide repeat interactions: to TPR or not to TPR?|
|Source||Trends Biochem. Sci. 20:257-259(1995).|
|4||Authors||Das A.K., Cohen P.W., Barford D.|
|Title||The structure of the tetratricopeptide repeats of protein phosphatase 5: implications for TPR-mediated protein-protein interactions.|
|Source||EMBO J. 17:1192-1199(1998).|
|5||Authors||D'Andrea L.D., Regan L.|
|Source||Trends Biochem. Sci. 28:655-662(2003).|