| Structural highlights
Function
TCPA_HUMAN Component of the chaperonin-containing T-complex (TRiC), a molecular chaperone complex that assists the folding of proteins upon ATP hydrolysis (PubMed:25467444). The TRiC complex mediates the folding of WRAP53/TCAB1, thereby regulating telomere maintenance (PubMed:25467444). As part of the TRiC complex may play a role in the assembly of BBSome, a complex involved in ciliogenesis regulating transports vesicles to the cilia (PubMed:20080638). The TRiC complex plays a role in the folding of actin and tubulin (Probable).[1] [2]
Publication Abstract from PubMed
The integrity of a cell's proteome depends on correct folding of polypeptides by chaperonins. The chaperonin TCP-1 ring complex (TRiC) acts as obligate folder for >10% of cytosolic proteins, including he cytoskeletal proteins actin and tubulin. Although its architecture and how it recognizes folding substrates are emerging from structural studies, the subsequent fate of substrates inside the TRiC chamber is not defined. We trapped endogenous human TRiC with substrates (actin, tubulin) and cochaperone (PhLP2A) at different folding stages, for structure determination by cryo-EM. The already-folded regions of client proteins are anchored at the chamber wall, positioning unstructured regions toward the central space to achieve their native fold. Substrates engage with different sections of the chamber during the folding cycle, coupled to TRiC open-and-close transitions. Further, the cochaperone PhLP2A modulates folding, acting as a molecular strut between substrate and TRiC chamber. Our structural snapshots piece together an emerging model of client protein folding within TRiC.
Snapshots of actin and tubulin folding inside the TRiC chaperonin.,Kelly JJ, Tranter D, Pardon E, Chi G, Kramer H, Happonen L, Knee KM, Janz JM, Steyaert J, Bulawa C, Paavilainen VO, Huiskonen JT, Yue WW Nat Struct Mol Biol. 2022 May;29(5):420-429. doi: 10.1038/s41594-022-00755-1. , Epub 2022 Apr 21. PMID:35449234[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Seo S, Baye LM, Schulz NP, Beck JS, Zhang Q, Slusarski DC, Sheffield VC. BBS6, BBS10, and BBS12 form a complex with CCT/TRiC family chaperonins and mediate BBSome assembly. Proc Natl Acad Sci U S A. 2010 Jan 4. PMID:20080638 doi:http://dx.doi.org/0910268107
- ↑ Freund A, Zhong FL, Venteicher AS, Meng Z, Veenstra TD, Frydman J, Artandi SE. Proteostatic control of telomerase function through TRiC-mediated folding of TCAB1. Cell. 2014 Dec 4;159(6):1389-403. doi: 10.1016/j.cell.2014.10.059. Epub 2014 Nov , 20. PMID:25467444 doi:http://dx.doi.org/10.1016/j.cell.2014.10.059
- ↑ Kelly JJ, Tranter D, Pardon E, Chi G, Kramer H, Happonen L, Knee KM, Janz JM, Steyaert J, Bulawa C, Paavilainen VO, Huiskonen JT, Yue WW. Snapshots of actin and tubulin folding inside the TRiC chaperonin. Nat Struct Mol Biol. 2022 May;29(5):420-429. PMID:35449234 doi:10.1038/s41594-022-00755-1
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