In tailing, adenylate residues are added at 3 end

Options

A. With the help of gyanyl transferase
B. In a template independent manner
C. With the help of methyl transferase
D. Of hn- RNA of E.coil

Answer

### Step-by-Step Solution:

1. **Understanding Tailing in mRNA Processing**:
- Tailing refers to the addition of adenylate (poly-A) residues to the 3' end of the mRNA molecule. This process is crucial for mRNA stability and regulation of translation.

2. **Identifying the Type of Process**:
- The addition of adenylate residues occurs in a template-independent manner. This means that the addition does not require a template strand of nucleic acid to guide the addition of the adenylate residues.

3. **Analyzing the Options**:
- **Option 1: With the help of guanyl transferase**: This is incorrect because guanyl transferase is involved in the capping process at the 5' end, not in tailing.
- **Option 2: In a template independent manner**: This is correct as the addition of adenylate residues does not rely on a template.
- **Option 3: With the help of methyl transferase**: This is incorrect as methyl transferases are involved in adding methyl groups, primarily during capping.
- **Option 4: Of hnRNA of E. coli**: This is misleading because while hnRNA (heteronuclear RNA) is a term used for primary mRNA transcripts, the process of tailing is not specific to E. coli in this context.

4. **Selecting the Correct Option**:
- Based on the analysis, the correct answer is **Option 2: In a template independent manner**.

### Final Answer:
The correct option is **Option 2: In a template independent manner**.

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