Luciferase is an enzyme that produces light through a chemical reaction, a process known as bioluminescence. This enzyme is found in various organisms, including fireflies and certain types of bacteria. When luciferase interacts with its substrate, luciferin, in the presence of oxygen, it catalyzes a reaction that emits light, often used by these organisms for communication or attracting mates. In scientific research, luciferase is utilized as a reporter gene in molecular biology. By attaching the luciferase gene to a gene of interest, researchers can measure gene expression by detecting the light produced. This technique is valuable in studying cellular processes and developing new therapies.