In this blog post, we’ll explore how small errors that can occur during protein synthesis can have fatal consequences for life.
Proteins are the primary building blocks of our bodies. Whether in the formation of muscles or the composition of hair, skin, and nails, the role of proteins is evident. Proteins do more than simply form the body’s structure; they play various roles essential for sustaining life, such as hormones, enzymes, and antibodies. For example, hormones enable communication between the body’s various organs, enzymes catalyze biochemical reactions, and antibodies protect the body from external pathogens. As such, proteins are key elements that maintain the balance and harmony of the entire body, and their importance cannot be overstated.
At this point, a question naturally arises: Where and how are these proteins actually made? Let’s head to the “kitchen” known as the cell to find the answer.
To cook a dish called “protein,” you first need a recipe. The recipe for proteins is stored in DNA, which contains genetic information, so we enter the cell nucleus—the place where DNA is kept. DNA acts as a kind of “blueprint of life,” specifying exactly what function each protein will perform and what shape it will take. Since proteins are made based on this blueprint, DNA plays an absolutely crucial role within the cell. While this blueprint is important in itself, protecting it from damage is also crucial.
After scanning through the DNA, you select the one you want. Overjoyed, you grab it and try to dash straight out to the cytoplasm—the kitchen—but lo and behold, this recipe is so precious that taking it out is strictly forbidden. You have no choice but to follow the rules. I’ll have to take a copy of the recipe with me. This is where mRNA comes in. The information contained in the DNA is transferred to the mRNA. This process is extremely precise, and not even a single small error is allowed. If the DNA’s information isn’t accurately conveyed to the mRNA, there’s a risk that the protein won’t be produced correctly. After carefully returning our precious DNA to its proper place, I made it safely out to the cytoplasm with the mRNA.
Now that we have the recipe, let’s get started with the actual cooking. We gently place the mRNA onto the ribosomes—the floating “cooking tables” in the cytoplasm. Our chefs, the tRNAs, are already waiting nearby. The tRNAs act as “delivery people” who transport the amino acids that make up proteins; without them, protein synthesis would be impossible. As the mRNA unfolds on the ribosome, the tRNAs quickly begin to decode it. The tRNAs are highly skilled and very orderly, having undergone extensive training. Following the instructions written on the mRNA, they select the appropriate amino acids from the twenty available ingredients, carry them one by one, and place them on the cooking table. At the same time, the rRNAs, which serve as the cooking utensils, diligently perform their roles at the cooking table. They link the ingredients together to form a sequence of amino acids, also known as a polypeptide. This process continues nonstop until the “stop” signal is read in the mRNA.
Once the signal that it’s finished is transmitted, this long polypeptide chain is carried away from the cooking table as a splendid dish. Now, let’s decorate this dish even more beautifully. Using a decorative technique called hydrogen bonding, we shape this chain into a ring. Looking it over, it seems something is still missing. Ah, a great idea comes to mind. We fold this ring a few more times to form a shape resembling a sphere. Finally, a beautiful culinary masterpiece—the protein—is complete. Doesn’t looking at it bring a satisfied smile to your face?
One important point to note here is that the process of cooking a protein tolerates not even the slightest mistake. If things go even slightly wrong at any point, the desired result will not be achieved. The original DNA recipe must not undergo mutation. Nor must information be incorrectly transferred to the mRNA copy of the recipe. The chef, tRNA, must not cause any problems while decoding the mRNA. These seemingly minor issues have a massive impact on protein synthesis.
For example, let’s say you intended to cook hemoglobin, a protein that carries oxygen. But things go wrong from the very beginning. The original recipe, DNA, contains incorrect information due to a mutation. If the process starts off on the wrong foot, what will the result be? Naturally, it ends in failure. This results in sickle-shaped red blood cells, which cause anemia in our bodies. Due to a single, minute difference in the information contained within the DNA, a substance that should benefit our bodies has become the very culprit that destroys it.
Protein synthesis is a process that is both mysterious and precise. Like cooking, this process must be meticulous. Proteins are that important and essential for the survival of living organisms. Through this intricate process, life is sustained, and we are able to live day by day. This is the true art of protein synthesis.
