Fusion proteins are made by joining parts of different proteins into one. Labs use them for tags, purification, tracking, or to combine two activities in a single tool. For example, fluorescent reporters or Fc-fusions are common. What matters most is that both parts still work. If the domains fold right and the linkers don’t get in the way, the protein stays stable and active. When that happens, experiments run smoother and less time is wasted.
