Until this point, we have talked a lot about DNA. Don't get us wrong. DNA is some pretty important stuff. We would even say it has rock star status. Seriously. Watch CSI or Bones. DNA all over the place.
DNA is a rock star because it provides all the information that a cell or organism needs to live and thrive. It can be also used to identify serial killers, mass murderers, or even your daddy (The Maury Povich Show—"You are the father!")
But, what about the other biological molecules, like RNA? Or protein? Don't they deserve a little attention?
They sure do. Without RNA and proteins, DNA is a long code of information, or a book in an unknown language. In other words, a lone DNA is about as good to you as the original untranslated Epic of Gilgamesh, an ancient Sumerian poem. Only through translation of the DNA message into RNA and protein does the information in DNA become actually useful. RNA and proteins take the script (DNA) and bring it to life. Take that, DNA.
In fact, it is the expression pattern of genes from DNA, not the DNA itself, which distinguishes one cell type from another. The DNA in a skin cell and a cell in your stomach will be exactly the same. The RNA and proteins produced from that DNA message will be what differs between the two cells, making each cell have its own identity. Sounds important? It is.
Perhaps even more importantly, the levels of RNA and protein produced can change even within the same cell over time. These changes can occur in response to changes in the environment or during diseases such as cancer.
The time has come for us to bring RNA and proteins into the spotlight. We will talk about how these underdogs are created and how altering the amounts of these biological molecules are essential for survival. Heavy stuff.
The process by which the information in DNA is used to produce RNA. The RNA produced from transcription can then be decoded to create a sequence of amino acids.
The process of using an RNA template to create a polypeptide or protein made of amino acids.
These processes might seem complicated and confusing, but the basic principles aren't hard. In fact, we have some good news. Remember your friends, DNA polymerases and the base-pairing rules from DNA replication? They'll visit you again here. In fact, you can probably figure out how transcription works by understanding the basics of DNA replication. We'll also show you that deciphering translation isn't bad either if you know the right code. Don't worry; it is much easier than being a code-breaker at NSA, but just as cool.
This stuff will be a blast. We can feel your excitement through the screen. After all, the only thing better than learning about gene expression is knowing you are about to ace your exam on gene expression.