In this video, we're going to begin our lesson on the steps of translation. Similarly to transcription, the process of translation also consists of 3 steps, and they are named the same as they are in transcription. It starts with the initiation process, and then it moves on into the elongation process, and last but not least, it moves on to the termination process. As we move forward in our course, we're going to talk about each of these three steps of translation in their own separate videos, starting with the initiation process.
In the initiation of translation, initiation just means the start or the beginning of the process. During the initiation of translation, it turns out that the small ribosomal subunit of the ribosome is first going to bind to the messenger RNA and a tRNA before the large ribosomal subunit even comes into play and binds. If we look at our image down below at the initiation of translation, notice that at the very beginning, the small ribosomal subunit, which we're showing you here, is going to bind to the messenger RNA, the mRNA first. The messenger RNA is then going to associate with the tRNA that you see here. The small ribosomal subunit is going to bind to the messenger RNA and the tRNA before this large ribosomal subunit over here, the large ribosomal subunit, even comes into play. That's really the sequence of events here, the small ribosomal subunit binding to the mRNA, then the tRNA, and then lastly here, the large ribosomal subunit is the last component to come into play during initiation.
One thing to note is that the mRNA, the messenger RNA, is going to contain the codons, the 3 nucleotide sequences. The very first codon is going to be the start codon. It's what's known as the start codon. The start codon is AUG. AUG is the start codon that specifies the amino acid methionine or MET. The start codon AUG that specifies the amino acid methionine is going to initiate the start of translation during this initiation process. Here in the mRNA, we have the codon AUG, and this is going to be the start codon. The codons specify amino acids through the tRNAs, the transfer RNAs, which have anticodons that are complementary to the codon. The tRNA is going to be a charged tRNA that is attached to an amino acid. This amino acid, that corresponds with the start codon is methionine, which is abbreviated as MET. We can put MET in here, and that is going to be the first amino acid in the chain of the polypeptide chain.
The initiation of translation can be quite a complex process. It involves several proteins that are called initiation factors, which we're not showing you here in this image. Translation initiation requires energy as well, which we are showing you the energy here, to remind you that it does require energy. Ultimately, at the end of the initiation of translation, we have the complete intact ribosome bound to the messenger RNA and the very first tRNA, that corresponds with the start codon, and the amino acid methionine.
This here concludes our introduction to the initiation of translation and the steps of translation. We'll be able to talk more about these steps of translation as we move forward in our course, continuing with elongation and then, of course, ending with termination. So I'll see you all in our next video.