The Powerhouse of Cells: How Mitochondria Control Energy and Disease

Mitochondria are like tiny power plants inside our cells. They make most of the energy our cells need, called ATP, through a process called oxidative phosphorylation. This process uses the electron transport chain (ETC) to pump protons and create an energy gradient, which is then used to make ATP. However, too much of this energy can lead to harmful molecules called reactive oxygen species (ROS). At the heart of this process is an enzyme called cytochrome c oxidase (COX). It works with another protein, cytochrome c (Cytc), to control the energy gradient and, therefore, ATP and ROS production. This reaction is tightly controlled by the cell to meet its energy needs and respond to stress. There are three main ways this reaction is controlled: through allosteric regulation, tissue-specific isoforms, and post-translational modifications. COX and Cytc are regulated by all of these methods, with many identified sites for phosphorylation and acetylation. When these controls go wrong, it can lead to diseases like strokes, heart attacks, inflammation, and diabetes. For example, changes in how COX is regulated can cause mitochondria to not work properly, contributing to the disease. Scientists are looking into how to fix these issues. One promising method is using infrared light therapy to control COX. This could change how we treat diseases where COX regulation has gone wrong.