T-complex protein Ring Complex (TRiC), otherwise known as Chaperonin Containing TCP-1 (CCT), is a

multiprotein complex A protein complex or multiprotein complex is a group of two or more associated polypeptide chains. Protein complexes are distinct from multidomain enzymes, in which multiple catalytic domains are found in a single polypeptide chain. Protein c ...

and the chaperonin of eukaryotic cells. Like the bacterial GroEL, the TRiC complex aids in the folding of ~10% of the proteome, and

actin Actin is a family of globular multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in muscle fibrils. It is found in essentially all eukaryotic cells, where it may be present at a concentration of ...

and tubulin are some of its best known substrates. TRiC is an example of a biological machine that folds substrates within the central cavity of its barrel-like assembly using the energy from ATP hydrolysis.

Subunits

The human TRiC complex is formed by two rings containing 8 similar but non-identical subunits, each with molecular weights of ~60 kDa. The two rings are stacked in an asymmetrical fashion, forming a barrel-like structure with a molecular weight of ~1 MDa. Molecular weight of human subunits. Counterclockwise from the exterior, each ring is made of the subunits in the following order: 6-8-7-5-2-4-1-3.

Evolution

The CCT evolved from the archaeal thermosome ~2Gya, with the two subunits diversifying into multiple units. The CCT changed from having one type of subunit, to having two, three, five, and finally eight types.

Notes

References

{{Portal bar, Biology, border=no Gene expression Protein complexes

Subunits

Evolution

See also

Notes

References