Correct option is C
Explanation:
- Translation initiation involves several key steps, and one of the critical factors is IF3, which plays an important role during the assembly of the ribosome in prokaryotic translation.
- IF3 (Initiation Factor 3) is a protein factor that prevents premature association of the 30S and 50S ribosomal subunits during translation initiation.
- IF3 functions as an anti-association factor by binding to the 30S ribosomal subunit, blocking the association with the 50S ribosomal subunit until the mRNA and initiator tRNA are properly aligned.
- Once the mRNA and initiator tRNA are in place, IF3 helps ensure the correct assembly of the ribosome for translation to begin.
Thus, IF3 is the correct factor that serves as the anti-association factor for the 30S and 50S subunits.
Information Booster
- IF3 binds to the 30S subunit, preventing premature association with the 50S subunit until initiation is ready.
- IF3 also helps stabilize the mRNA-ribosome interaction during the initial stages of translation.
- Translation initiation involves the 30S subunit binding to mRNA, with the initiator tRNA binding to the start codon.
- IF1 and IF2 also play roles in translation initiation, but IF1 stabilizes the 30S initiation complex and IF2 assists with GTP hydrolysis and the entry of the initiator tRNA.
- IF3 is essential for proper initiation, as its absence leads to faulty ribosome assembly and translation initiation errors.
- The anti-association role of IF3 ensures that translation begins only after the ribosome is fully assembled with the correct components.
Additional Information
- Option (1) IF1 → Incorrect; IF1 stabilizes the ribosome in its 30S form, not as an anti-association factor.
- Option (2) IF2 → Incorrect; IF2 is a GTPase involved in delivering the initiator tRNA to the ribosome and does not prevent subunit association.
- Option (4) RRF (Ribosome Recycling Factor) → Incorrect; RRF is involved in disassembling the ribosome after translation, not in the initiation process.
