If you were pivy to my first intro “course” in genetics 101, the basics, you got a fast and furious introduction to DNA and what it does. Again briefly, DNA works as a coded system of information storage to tell the cells of our bodies what to do and how to get it done. However, as you might expect, there’s quite a few layers in between that I glossed over on the first pass. How the cell reads its DNA and performs necessary functions is known as the central dogma
The process of going from DNA to functional product is simple enough if you ignore the millions of layers of complexity, which I think is probably for the best. You begin with DNA, it’s deciphered into RNA, which leads to protein – the cells’ worker ants.
Step 1- Replication – exactly like it sounds. DNA making an exact copy of itself. This happens every time a cell of yours divides, and is the basis for DNA propagating itself, especially into future generations.
To decipher the DNA, we gotta get it down to the genes. A gene is, in its strictest definition, the hereditary unit in genetics. As far as we’re concerned, it’s a stretch of letters that are code for a certain protein. Problem is, there’s roughly 25-30,000 genes in a human, encoded by 3 billion bases organized on a level similar to that tangle that your iPod headphones always seem to be in. Obviously the body has to get down to some workable unit of information somehow.
Step 2 – To get down to that small piece, we make RNA via a process called transcription. It’s akin to chopping a piece of DNA out of the big genome, and then taking only one of the strands. Because its smaller and single stranded, fit’s much easier for the body to handle and turn into protein, but it’s also much less stable in our cells. Hence why DNA is what we use to store our genetic info. So there’s several different types of RNA, but the most common and important one (for our purposes here) is messenger RNA. Aptly named, eh? Scientists are so creative sometimes.
Once we have a piece of messenger RNA we’re ready to make some protein via Step 3. Appropriately, this process is known as translation. We translate the code of letters in transcript the into a functional protein for the body to utilize. The translational machinery will scan the RNA message to decipher the code and hook up a chain of amino acids based on the sequence of nucleotides in the message. This machinery is like the cell’s own little Vanna White patrol. Just bring the right letter into the right place.
We start with the compound, complex structure of DNA. The body makes a usable piece from the coded genes, and then deciphers that code to make a functional tool for the cells to use. Obviously, each of these processes are the product of decades of research, with hundreds if no thousands of labs working on each of them to learn more and more. Future posts may go into each of these processes more thoroughly if there’s any interest in learning further. For now, I think a general understanding of what a gene does and how it gets to that point is an important thing to learn.
As always, questions and comments are more than welcome. Take care world.
Thanks and Gig ‘em.