Processing of mRNA molecules

 Processing of mRNA molecules 

mRNA undergoes several modifications before it is being translated. They are

 

1.           Addition of blocks of poly A, containing 200 (or) more AMP residues to the 3' end of messenger RNAs. This addition of poly A tail takes place in the nucleus.

 

2.           A methylated Guanine nucleotide called as “5' cap” is added to the 5' end of mRNA molecule.

 

3.           Methylation occurs in the internal adenylate nucleotides at their N-6 position. It’s function is not known.Thus mRNA is processed to get the active mRNA molecule.

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