Question

Which is present at $5^{\prime }$ end of eukaryotic $mRNA$?

• A. Poly-A tail
• B. Modified C at 5'
• C. 7 mG
• D. Poly-C

Answer 1

Answer: (C)

At the $5^{\prime }$ end of eukaryotic $mRNA,7mG$ ($7$-methyl guanosine) is present. In eukaryotes, primary transcript is often larger than the functional $RNAs$. Therefore, post-transcription processing is required to convert primary transcript of all types of $RNAs$ into functional $RNAs$ . It is of four types; cleavage, splicing, terminal addition and nucleotide modification. The terminal additions include capping and tailing. In capping, $7mG$ is added to $5^{\prime }$ end of $mRNA$ .