How does the autophagosome form?

Autophagosome formation starts with the creation of a double-membrane structure called the phagophore, which engulfs the material to be broken down. The phagophore expands to surround the cargo, creating a sealed compartment (autophagosome). The outer membrane of the autophagosome then merges with a digestive compartment (lysosome), allowing the contents to be broken down by enzymes inside. Inside the lysosome, the inner membrane of the autophagosome and its cargo are degraded into smaller molecules. Lastly, the resulting breakdown products are released back into the cytoplasm for reuse.