Up until now we have mainly focused on RNA as a strand of nucleic acids that contains the information encoded by DNA. RNA is so much more.
It turns out that there are many different types of RNA. In eukaryotes, these RNAs are grouped by which RNA polymerase transcribes them.
- RNA polymerase I family members transcribe the rDNA genes, which result in ribosomal RNAs (rRNAs).
- RNA polymerase II family members transcribe the messenger RNAs (mRNAs) and some structural RNAs. mRNAs are the type of RNA that encode for proteins.
- RNA polymerase III family members transcribe transfer RNAs (tRNAs). There are also a wide variety of small RNAs that have numerous regulatory roles in the cell. We'll talk about the roles and functions of all these RNAs in more detail later.
What's translation all about, anyway?
When it comes to translation, it is all about cracking the code. The RNA code, of course.
The RNA code is one of the most important biological laws (if not the
most important law). It is called the central dogma of biology after all….have you forgotten already?
Here's a little refresher.
The central dogma is
DNA → RNA → Protein.
The cell needs to take the information in the RNA and translate it into a totally new language: the protein language. Serious stuff.
Don't worry though, you will be speaking protein language in no time.