In mouse kidney tissue, RNAScope analysis revealed that CG1 (Ccng1) RNA was upregulated in PTCs (labeled by hepatocyte nuclear factor 4α [Hnf4a]; refs. 25, 26), in 3 models of CKD (aristolochic acid [AA], repeated low-dose cisplatin [Rep low cis], and unilateral ureteral obstruction [UUO]) when compared with control uninjured kidneys (Figure 1, C and D). Here, CCNG1 is linked to chronic kidney disease.