Toll-like receptor (TLR)-specific co-chaperone for HSP90B1. Required for proper TLR folding, except that of TLR3, and hence controls TLR exit from the endoplasmic reticulum. Consequently, required for both innate and adaptive immune responses (By similarity). Interacts with HSP90B1; this interaction is disrupted in the presence of ATP. Interacts with TLR1, TLR2, TLR4 and TLR9 (By similarity). Strongest interaction with TLR4 (By similarity). The disease is caused by variants affecting the gene represented in this entry. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Belongs to the canopy family.