Question

RNA polymerase responsible for the synthesis of tRNA

• A. RNA Pol 1
• B. RNA Pol 2
• C. RNA Pol 3
• D. RNA Pol 1 and 2

Hint:

A simple mnemonic to remember the eukaryotic RNA polymerases: \textbf{Pol I} \(\rightarrow\) \textbf{r}RNA (most abundant) \textbf{Pol II} \(\rightarrow\) \textbf{m}RNA (most diverse) \textbf{Pol III} \(\rightarrow\) \textbf{t}RNA (and other tiny RNAs) The numbers 1, 2, 3 correspond to the order of the RNA types r, m, t in the word "rampart".

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
In eukaryotic cells, transcription (the synthesis of RNA from a DNA template) is carried out by three distinct RNA polymerases, each responsible for transcribing different classes of genes.
Step 2: Detailed Explanation:
The division of labor among the eukaryotic RNA polymerases is as follows:
RNA Polymerase I (Pol I): Located in the nucleolus, it is responsible for transcribing the genes for most ribosomal RNAs (rRNAs), specifically the 18S, 5.8S, and 28S rRNA subunits.
RNA Polymerase II (Pol II): Located in the nucleoplasm, it transcribes all protein-coding genes to produce messenger RNAs (mRNAs). It also synthesizes most small nuclear RNAs (snRNAs) and microRNAs (miRNAs).
RNA Polymerase III (Pol III): Located in the nucleoplasm, it transcribes the genes for small, functional RNAs. This includes all transfer RNAs (tRNAs), the 5S ribosomal RNA, and the U6 small nuclear RNA.
Step 3: Final Answer:
Based on this division, the synthesis of transfer RNA (tRNA) is the responsibility of RNA Polymerase III.