Monday, September 24, 2012

DNA - RNA- Protein!

Cracking the genetic code! You know? Your DNA is made up of A,T,G,C (adenine, guanine, cytosine, thymine) These four letter are repeated through out the sequence. This DNA codes for Protein to be specific amino acids.

How your DNA is decoded?
Your DNA undergoes translation, that is, it gets converted as RNA and further this RNA is converted into proteins by transcription.

Translation? How it happens? DNA is a double helix as we all know. This double helix unwinds and now it has two trands, right? one strand is called a codon strand and the other is anti codon.

The codon strand is the coding strand. So, you think that you mut translate this codon strand? But, it is not certainly. The RNA is formed "complementary" to the anticodon strand!

You think, why? Here we go with the explanation. The word "complementary" has the importance here. Both the DNA strands are complementary to each other. As we know, the DNA has four nucleotide repeated through out namely ATGC.

Example of a complementary DNA strand:

ATGCTTGCGACT ---> Coding strand
TACGAACGCTGA ---> Anticodon strand

The coding strand has the exact details. But, the RNA is going to be formed in the complementary basis, so, the anti codon strand must be translated as follows.

ATGCTTGCGACT ---> Coding strand
AUGCUUGCGACU ---> RNA formed from anticodon by RNA polymerase enzyme.
TACGAACGCTGA ---> Anticodon strand

Note the imilarity between the coding trand and the RNA formed. RNA don't have "T", but, "U" instead. Here, by translating the anti codon strand we get the exact copy like the coding strand.

Further this RNA is trancribed as proteins. Each 3 letter set of the RNA codes for an amino acid of the protein.


This table describes the three letter coding format.

In this way your genetic code is cracked and information is extracted out. If there is any error in the code, then there will be error in the amino acid synthesis leading to Genetic diseases!

:) I hope you can understand this with little basics of biology. I tried my best to explain it simple. Doubts? Then comment! :)

Have a good time!

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