The CS and CHORD (Pfam:PF04968) are fused into a single polypeptide chain in metazoans but are found in separate proteins in plants; this is thought to be indicative of an interaction between CS and CHORD [1]. It has been suggested that the CS domain is a binding module for HSP90, implying that CS domain-containing proteins are involved in recruiting heat shock proteins to multiprotein assemblies [2]. Two CS domains are found at the N-terminus of Ubiquitin carboxyl-terminal hydrolase 19 (USP19) (Swiss:O94966), these domains may play a role in the interaction of USP19 with cellular inhibitor of apoptosis 2 [3].

1: A novel class of eukaryotic zinc-binding proteins is required for disease resistance signaling in barley and development in C. elegans. Shirasu K, Lahaye T, Tan MW, Zhou F, Azevedo C, Schulze-Lefert P; Cell 1999;99:355-366. PMID:10571178

2: Human Sgt1 binds HSP90 through the CHORD-Sgt1 domain and not the tetratricopeptide repeat domain. Lee YT, Jacob J, Michowski W, Nowotny M, Kuznicki J, Chazin WJ; J Biol Chem 2004;279:16511-16517. PMID:14761955

3: The USP19 deubiquitinase regulates the stability of c-IAP1 and c-IAP2. Mei Y, Hahn AA, Hu S, Yang X; J Biol Chem. 2011;286:35380-35387. PMID:21849505