TRiC (TCP-1 Ring Complex) or CCT (Chaperonin Containing TCP-1) is a multi-subunit, double-ringed, ATP-driven cytosolic eukaryotic chaperonin complex that is constitutively expressed and facilitates the folding of several proteins like actin and tubulin (Frydman et al. 1992; Llorca et al. 1999; Berger et al. 2018). Its role in many cellular processes like differentiation, viral replication, and heart contractility were elucidated recently (Melkani et al. 2017; Knowlton et al. 2018; Ohhara et al.

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... 2019). Its functional defects are also associated with neurodegenerative diseases and cancer (Tam et al. 2006; Boudiaf-Benmammar et al. 2013). Temperature sensitive mutants of Saccharomyces cerevisiae CCT have been used in different studies, especially those involving genetic screens to identify CCT-interacting proteins (Kabir and Sherman 2008). The CCT1-CCT8 genes encode eight different subunits of the complex; the mutant allele cct1-2 has G423D replacement in the conserved ATP binding/hydrolysis domain in the subunit Cct1p. cct4-1 (G345D), the mutation in subunit Cct4p, affects ATP binding, intra and inter-ring co-operativity (Shimon et al. 2008). cct1-2 and cct4-1 grew well at 30°C (permissive temperature), showed retarded growth at 35°C (semi-permissive temperature) and failed to grow at 37°C (restrictive temperature).