Synthetic proteins can now force different parts of a human cell to fuse together on command.

In nature, the internal organs of a cell, like the mitochondria and the endoplasmic reticulum, are kept strictly separate. Researchers have now used machine learning to design custom fusogens that can bridge these biological membranes and force them to merge. This creates a powerful tool for synthetic biology that allows scientists to rewire the internal architecture of a living cell. By controlling which parts of the cell touch, they can manipulate how energy is produced or how proteins are folded. This breakthrough could lead to engineered cells that perform complex industrial or medical tasks that were previously impossible.