INAVA condensates as a mediator of cellular proteostasis. (A) HCT8-INAVA-GFP cells were treated with IL-1β (10 ng/ml) for 1 h and ganetespib (1 μM) and 17AAG (10 μM) for 1.5 h. Cells were fixed and stained with conjugated ubiquitin antibody FK2. Scale bar = 10 μm. (B) HCT8-INAVA-GFP cells expressing doxycycline-inducible myc-βTrCP2 were treated with doxycycline (1 μg/ml) overnight followed by the condensate inducers as in A or H₂O₂ (1 mM) for 90 min. Cells were fixed and stained with α-myc for βTrCP2. Scale bar = 10 μm. (C) HEK293T cells were transfected with HA-ubiquitin with stably expressed empty vector (EV), GFP-INAVA long or short isoform, and a CUPID domain mutant (C141A). Cells were treated with or without H₂O₂ (1 mM) for 90 min. Whole-cell lysates were collected and analyzed by immunoblot for HA (ubiquitin), GFP (INAVA), and actin. The unit of measure for the Western blots is kilodaltons.