Retinoic Acid Receptor Gamma (RARγ) Promotes Cartilage Destruction through Positive Feedback Activation of NF-κB Pathway in Human Osteoarthritis

Figure 5

RARγ interacted with IκBα and promoted the activation of NF-κB signaling pathway. (a) C28/I2 cells overexpressing RARγ were treated with TNF-α (30 ng/mL) for 4 hours, and the activation of NF-κB signaling pathway was detected by western blot. (b) Online public databases predict that RARγ may interact with IκBα and P65 proteins in NF-κB signaling pathways (STRING, https://cn.string-db.org/and GeneMANIA, http://genemania.org/). (c) CO-IP assay was used to verify whether the exogenous overexpressed RARγ-Flag protein interacts with IκBα or P65. (d) The CO-IP assay was further used to verify whether the endogenous RARγ protein interacted with IκBα or P65. (e) The colocalization of RARγ and IκBα in C28/I2 cells was detected by immunofluorescence. Magnification in ×1000.

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