Today was weird, I didn't really understand today's lesson, hmm. I just have to sleep. I am exhausted. I will be good in the morning..
Hi Myra, I am DNA. Hope you are sleeping well. You are probably wondering what I do, I carry all the information the you need to work and look. Today together we will be going through a process called protein synthesis. Now I have a question, do you what a protein is?
Hi DNA! Protein? Not really...
That alright Myra! A protein is a molecule made up amino acids. Proteins help build your muscles, organs, etc. Now before we go, I must warn you I will not be staying in this form, I will be changing.
Oh yea! I almost forgot..I am made up of three things a sugar (deoxyribose), a phosphate, and a nitrogen base. My nitrogen base has 4 different nucleotides.
I am telling you this Myra because you will see how these nucleotides will change with time. Okay, now let's begin our journey!
Adenine
Cytosine
Thymine
Guanine
Ohhh ok but wait why does protein synthesis need you?
Protein synthesis needs me because I carry the information for how to make a protein.
Hey DNA I have a question, what's protein synthesis?
Great question Myra! Protein are made in cells. When a cell makes a protein it's called protein synthesis.
UNZIPGENE
First Step
Oooo...Now Myra protein synthesis is split into 2 processes transcription and translation. We have reached the first step, transcription. This is when I am copied into mRNA. Transcription occurs in the nucleus of a cell.
A
G
C
U
Second Step
In the second step of transcription we match my exposed nucleotides with RNA nucleotides. Now Myra this is where the ATCG comes into action, since I am getting copied into mRNA instead of ATCG we will have AUCG. (U - Uracil). Since we matched these nucleotides, we are left with a single strand of mRNA.
DNA: ACTGmRNA: UGAG
Third/Fourth Step
Now I am mRNA, my DNA molecule zips back up, and I get released into the cytoplasm.
Indeed Myra! You are getting the hang of this.
Wow! This is amazing! DNA you have changed your form, just like you said. Since we done with transcription, we go into translation right?
First Step
I attach myself to a Ribosome.
Ribosome
Now we are in the second process of protein synthesis, translation. This is when I get translated into polypeptides that make up the protein. Polypeptides are a chain of amino acids, which later fold into a protein. Translation occurs in the ribosome.
In the second step. The ribosome reads the codons I have. A codon is a set of three nucleotides. The ribosome starts reading at AUG.
Second Step
As the tRNA drops off Amino acids, the ribosome binds the amino acids together using peptide bonds until the stop codon is reached. Which then the completed polypeptide chain is released.
In the third step of translation. tRNA act like taxies and drop amino acids that coordinate with my codons
tRNA
Amino Acid
Fourth Fifth Steps
Third Step
mRNA : AUGCAGUAGAmino Acid : Met - Glu - Stop
Peptide bonds
Amino Acid
DNA--TRANSCRIPTION--mRNA--TRANSLATION--PROTEIN
Protein
I am still here, anyways I think it time for you to wake up, I hear someone yelling. It was great to have you along with me Myra!
With that protein synthesis is done.
Wow, just wow! Protein synthesis is fascinating! But that's a lot of steps DNA. Wait, DNA where did you go?