C-terminal wheel domain found in Saccharomyces cerevisiae Hsp70/Hsp90 co-chaperone Cns1, Homo sapiens tetratricopeptide repeat protein 4 (TTC4), and similar proteins
The family includes Hsp70/Hsp90 co-chaperone Cns1 from Saccharomyces cerevisiae and the human Cns1 homolog tetratricopeptide repeat protein 4 (TTC4), both of which contain a C-terminal wheel domain consisting of a twisted five-stranded beta sheet surrounded by several alpha helices. Cns1, also called cyclophilin seven suppressor 1, or STI1 stress-inducible protein homolog, binds to the molecular chaperones Hsp90 (HSC82 and HSP82) and Hsp70 (SSA1). It stimulates SSA1 ATPase activity, but not Hsp90 ATPase activity. It is involved in only a subset of Hsp90 functions. TTC4, also called TPR repeat protein 4, is a putative Hsp90 co-chaperone which interacts with CDC6 and shows alterations in transformed cells. It interacts with TBK1 and promotes Sendai virus (SeV)-induced host cell innate immune responses.
Jiyao W et al.(2023). "The conserved domain database in 2023.",