| Primary Identifier | IPR019544 | Type | Domain |
| Short Name | Tetratricopeptide_SHNi-TPR_dom |
| description | The tetratrico peptide repeat region (TPR) is a structural motif present in a wide range of proteins [, , ]. It mediates protein-protein interactions and the assembly of multiprotein complexes []. The TPR motif consists of 3-16 tandem-repeats of 34 amino acids residues, although individual TPR motifs can be dispersed in the protein sequence. Sequence alignment of the TPR domains reveals a consensus sequence defined by a pattern of small and large amino acids. TPR motifs have been identified in various different organisms, ranging from bacteria to humans. Proteins containing TPRs are involved in a variety of biological processes, such as cell cycle regulation, transcriptional control, mitochondrial and peroxisomal protein transport, neurogenesis and protein folding.The X-ray structure of a domain containing three TPRs from protein phosphatase 5 revealed that TPR adopts a helix-turn-helix arrangement, with adjacent TPR motifs packing in a parallel fashion, resulting in a spiral of repeating anti-parallel α-helices []. The two helices are denoted helix A and helix B. The packing angle between helix A and helix B is ~24 degrees within a single TPR and generates a right-handed superhelical shape. Helix A interacts with helix B and with helix A' of the next TPR. Two protein surfaces are generated: the inner concave surface is contributed to mainly by residue on helices A, and the other surface presents residues from both helices A and B. This entry represents SHNi-TPR (Sim3-Hif1-NASP interrupted TPR), a sequence that is an interrupted form of TPR repeat []. |
