The wheel domain is found at the C-terminus of yeast Cns1 and human TTC4 proteins [1]. The structure of the domain shows an overall fold consisting of a twisted five-stranded beta sheet surrounded by several alpha helices [1]. The Hsp90 chaperone machinery in eukaryotes comprises a number of distinct accessory factors. Cns1 is one of the few essential co-chaperones in yeast. Cns1 is important for maintaining translation elongation, specifically chaperoning the elongation factor eEF2 [1]. In this context, Cns1 interacts with the novel co-factor Hgh1 and forms a quaternary complex together with eEF2 and Hsp90 [1].

1: The Co-chaperone Cns1 and the Recruiter Protein Hgh1 Link Hsp90 to Translation Elongation via Chaperoning Elongation Factor 2. Schopf FH, Huber EM, Dodt C, Lopez A, Biebl MM, Rutz DA, Muhlhofer M, Richter G, Madl T, Sattler M, Groll M, Buchner J; Mol Cell. 2019;74:73-87. PMID:30876805