Mitochondrial Inner Membrane (IMM)

The mitochondrial inner membrane (IMM) separates the mitochondrial matrix from the intermembrane space and serves as the main functional barrier for small molecules and ions, maintaining distinct environments on either side and supporting essential bioenergetic processes. The IMM is highly folded into cristae, which greatly increase its surface area. It houses the electron transport chain, ATP synthase, and specific transporter proteins. It is rich in cardiolipin, a unique phospholipid that contributes to membrane impermeability. The IMM plays crucial roles in oxidative phosphorylation, selective permeability, establishing membrane potential, protein import, and apoptosis regulation. Alterations affecting its composition or structure can result in impaired oxidative phosphorylation and contribute to various diseases.