Dysfunction of the microbiota leads to decreased BA activity, reducing unconjugated BA and secondary BA production, weakening FXR activity, and exacerbating cirrhosis through various pathways: (1) In hepatocytes, FXR interacts with nuclear receptors such as peroxisome proliferator-activated receptors (PPAR)-α and liver X receptor (LXR)α to form heterodimers, regulating downstream target gene expression. The gene discussed is NR1H4; the disease is Cirrhosis.