Component of the chaperonin-containing T-complex (TRiC), a molecular chaperone complex that assists the folding of actin, tubulin and other proteins upon ATP hydrolysis (PubMed:25467444, PubMed:36493755, PubMed:35449234, PubMed:37193829). 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). {ECO:0000269|PubMed:20080638, ECO:0000269|PubMed:25467444, ECO:0000269|PubMed:35449234, ECO:0000269|PubMed:36493755, ECO:0000269|PubMed:37193829}. This is the function of CCT3 (chaperonin containing TCP1 subunit 3, Ensembl gene identifier ENSG00000163468).