The Life Cycle of a Protein
No protein is made to last forever. Just as DNA and RNA direct a coordinated process for protein creation, there is also a process for proteins to be broken down by the cell. We call this proteolysis or protein degradation.
Proteins are broken down for a number of reasons. First and foremost, it’s a strategy for quality control. After a string of protein building blocks are put together, they are bent and folded into a specific shape that allows the protein to interact with other proteins in a useful way. You can think of it like a daisy in a daisy chain- the stem needs to be carefully folded and tied or the daisy chain falls apart entirely. Cells have tools to identify misfolded proteins and break them down quickly to prevent problems.
Even beyond quality control, proteins have a certain lifespan within the cell. Regular protein recycling ensures that there is always an available supply of protein building blocks for the creation of new proteins. Removing older proteins also gives cells flexibility in terms of adjusting to environmental changes.Continue reading “Snapshot: What is Protein Degradation?”