Which of the following is not required during post transcritional processing in eukaryotes?

Options

A. Methyl guanosine triphosphate
B. Ligase
C. ScRNA
D. SnRNA

Answer

To determine which of the following is not required during post-transcriptional processing in eukaryotes, we need to analyze the options provided: methylguanosine triphosphate (often referred to as the 7-methylguanylate cap), ligase, SCRN, and SNRN.

### Step-by-Step Solution:

1. **Understanding Post-Transcriptional Processing**:
- In eukaryotes, after transcription, the primary RNA transcript undergoes several modifications to become mature mRNA. This process is known as post-transcriptional processing.

2. **Identifying the Key Steps in Post-Transcriptional Processing**:
- There are three main steps involved:
- **Capping**: The addition of a 7-methylguanylate cap to the 5' end of the RNA molecule.
- **Polyadenylation**: The addition of a poly-A tail to the 3' end of the RNA molecule.
- **Splicing**: The removal of introns (non-coding regions) and the joining of exons (coding regions) to form the mature RNA.

3. **Analyzing Each Option**:
- **Methylguanosine Triphosphate**: This is required for the capping process, where the 7-methylguanylate cap is added to the 5' end of the RNA.
- **Ligase**: This enzyme is involved in the ligation process, helping to join two RNA fragments together during splicing.
- **SNRN (Small Nuclear RNA)**: These molecules play a crucial role in splicing, helping to remove introns from the pre-mRNA.
- **SCRN (Small Conditional RNA)**: This is not a standard component of the post-transcriptional processing machinery in eukaryotes.

4. **Conclusion**:
- Based on the analysis, SCRN is not required during post-transcriptional processing in eukaryotes. Therefore, the correct answer is **SCRN**.

### Final Answer:
**SCRN** is not required during post-transcriptional processing in eukaryotes.

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