Advertisements
Advertisements
Question
Give an account of post transcriptional modifications of a eukaryotic mRNA.
Advertisements
Solution
The primary transcripts (hn-RNA) contain both the exons and the introns and are non-functional. Hence, it is subjected to a process called splicing where the introns are removed and exons are joined in a defined order. Intron is the portion of gene which is transcribed but not translated. In prokaryotes, hnRNA is absent so splicing in not required. hnRNA undergoes additional processing called as capping and tailing. In capping an unusual nucleotide (methyl guanosine triphosphate) is added to the 5′-end of hnRNA. In tailing, adenylate residues (200 - 300) are added at 3′-end in a template-independent manner. It is the fully processed hnRNA, now called mRNA, that is transported out of the nucleus for translation.
Process of Transcription in Eukaryotes
APPEARS IN
RELATED QUESTIONS
Depending upon the chemical nature of the template (DNA or RNA) and the nature of nucleic acids synthesised from it (DNA or RNA), list the types of nucleic acid polymerases.
Differentiate between the following:
mRNA and tRNA
Explain the process of transcription in Eukaryotes.
With regard to mature mRNA in eukaryotes.
Regulatory proteins are the accessory proteins that interact with RNA polymerase and affect its role in transcription. Which of the following statements is correct about regulatory protein?
The amino acid attaches to the tRNA at its ______.
In transcription in eukaryotes, heterogeneous nuclear RNA (hnRNA) is transcribed by ______.
In eukaryotes, the process of processing of primary transcript involves ______.
On the ribosome, mRNA binds ______ and two sites in the ______ for subsequent amino acids to bind to be close enough to each other for the formation of a peptide bond.
A special feature of viruses is that they:
Which of the following pair lack the unit membrane?
A ribozyme is an:
Identify the correct statement.
Identify the correct statement.
What are the functions of methylated guanasine cap?
- Assertion: Ribosomal RNA is synthesized in the nucleus of the cell.
- Reason: It is translated with the enzyme RNA polymerase III.
Streptokinase produced by bacterium Streptococcus is used for ______.
