Year: 1995
Type: review
Abstract: Tetratrico peptide repeat interactions: to T?R or not to TPR?The tetratrico peptide repeat (TPR) is a degenerate 34-amino acid repeated motif that is widespread in evolutionL TPR proteins have been discovered in organisms as diverse as bacteria and humans, and in a variety of subcellular locations, including the nucleus, the cytoplasm and mitochondria.Processes involving TPR proteins include cellcycle control, transcription repression, stress response, protein kinase inhibition, mitochondrial and peroxisomal protein transport and neurogenesisL Therefore, there appears to be no common biochemical function connecting TPR-containing proteins.TPRs are frequently tandemly arrayed, although it is also common for single or double TPRs to be found separated from the arrays (Fig. In).Comparison of TPRs from a variety of proteins reveals eight loosely conserved consensus residues (-W-LG-Y-A-F-A-P-; see Fig. 2a and Refs 2, 3) within the 34 amino acids that define the motif.These residues are conserved in terms of their size, hydrophobicity and spacing.The high degree of sequence diversity observed in TPRs is consistent with the diversity of function o[ TPR-containing proteins.TPR-TPR intsractions Overall, TPRs have a high probability of forming amphipathic a-helices 2,3 in two domains, A and B. Detailed secondary structure predictions have been made whereby domain A OV-LG-Y) forms a hydrophobic pocket into which the bulky phenylalanine sidechain of domain B (A-F-A) fits (the so-called knob and hole model 2, see Fig. lb).The prediction of this model is that TPRs interact with each other and therefor mediatc protein-protein interactions.These interactions could form intraand/or intermolecular contacts between protein segments.Evidence for direct TPR-TPR-mediated protein-protein interactions has not emerged, although some TPR-containing proteins, such as CDC16, CDC23 and CDC27 (Ref.4), have
Source: Trends in Biochemical Sciences
Authors: John R Lamb, Stuart Tugendreich, Phil Hieter
Institution: Johns Hopkins University
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $7,030
OpenAlex ID: W2038186997