The 5' Cap

The 5' cap is a protective and functional modification added to the beginning (5' end) of a messenger RNA (mRNA) molecule in cells. It’s a small chemical structure that helps the mRNA stay stable, exit the nucleus, and be recognized by the cell's protein-making machinery. This cap ensures the mRNA isn’t broken down quickly and helps the cell properly translate the genetic information into proteins. Think of it like a security tag or a protective cover that ensures the message is read accurately and efficiently.