TPRcontaining

TPR-containing refers to proteins that harbor tetratricopeptide repeat motifs, a family of structural repeats about 34 amino acids in length that commonly occur in tandem. The repeats assemble into a right-handed, elongated superhelix that provides a versatile surface for protein–protein interactions. When present in multiple copies, TPR modules create a modular scaffold capable of binding diverse partners with varying affinity and specificity.

Functionally, TPR-containing proteins act as adaptors, scaffolds, or regulatory subunits in a wide range of cellular processes. They frequently mediate the assembly and docking of multiprotein complexes, such as chaperone systems, signaling assemblies, or transport receptors. A characteristic role is to bind the conserved C-terminal motifs of partner proteins, notably the EEVD motif found on Hsp70 and Hsp90 chaperones in many eukaryotes. Notable examples include Hop/Sti1, a co-chaperone that coordinates Hsp70 and Hsp90 through its TPR domains, and FKBP52, a peptidyl-prolyl isomerase with TPR repeats that interfaces with chaperones.

Other TPR-containing proteins include protein phosphatase 5 (PPP5C), whose N-terminal repeats regulate phosphatase activity via chaperone interactions, and members of the TTC (tetratricopeptide repeat domain-containing) family such as TTC1 and TTC4. The motif is widespread across bacteria, archaea, and eukaryotes, reflecting its utility as a general protein-interaction module.

In research and biotechnology, TPR repeats are exploited as modular scaffolds to engineer synthetic protein assemblies, taking advantage of their predictable structure and binding properties.