Which protein is lipitor's main effector?

What protein does Lipitor (atorvastatin) mainly act on?

Lipitor (atorvastatin) is a statin that mainly inhibits an enzyme protein called HMG‑CoA reductase (3‑hydroxy‑3‑methylglutaryl‑CoA reductase). This is the key effector in the cholesterol synthesis pathway because blocking it reduces mevalonate production and lowers cholesterol levels.