To confirm the effect of PKNOX2 in pathological myocardial fibrosis, we generated fibroblast-specific PKNOX2 knockout mice (AAV9-Col1a2-Cre&PKNOX2 flox; Pknox2 CKO) and induced a heart failure model through transverse aortic constriction (TAC) operation (Fig. 8a). Here, COL1A2 is linked to heart failure.