Probable substrate receptor of CRL4 E3 ligase complexes acting as negative regulators of thermotolerance by disturbing the action of HSP90-1 and by preventing the expression of heat-inducible genes (e.g. HSP14.7, HSP21, At2g03020 and WRKY28). Protein modification; protein ubiquitination. Probable component of CULLIN4 (CUL4) RING ligase (CRL4) complexes (PubMed:25358503). Interacts with DDB1A and DDB1B (PubMed:25358503). Associates with HSP90-1 (PubMed:25358503). Accumulates in response to heat stress. Increased heat stress tolerance associated with the accumulation of HSP14.7, HSP21, At2g03020 and WRKY28. Belongs to the WD repeat RBAP46/RBAP48/MSI1 family.