To gain a better understanding of messenger RNA (mRNA), it is helpful to take a look inside a human cell, where mRNA plays a central role in the production of the proteins of our body. While the original instructions for building these proteins are stored in the cell nucleus, in our DNA. They are transcribed there into mRNA. Once the mRNA including the construction plan for a protein is produced, it exits the cell nucleus and presents the instructions to ribosomes whose job it is to read the instructions and assemble the corresponding protein.
A typical human cell contains more than a hundred thousand such mRNA molecules at any given time. And given that mRNA molecules begin to degrade after a few minutes, the ribosomes have only a limited amount of time in which to read the instructions. mRNA molecules, and with them the instructions for building any given protein, can also be manufactured in a laboratory. This procedure is used by vaccine manufacturers to develop .