Next, the expression of RACK1 was significantly increased in fibrotic kidneys compared to that in CL kidneys (Figure S3A-D) and was colocalized with PDGFRα+ mesenchymal cells and αSMA+ or Col1a1+ myofibroblasts in fibrotic kidneys (Figure S3D), implying that RACK1 may play a crucial role in FMT during renal fibrosis. The gene discussed is COL1A1; the disease is renal fibrosis.