According to the wobble hypothesis, a single tRNA can recognize more than one synonymous codon. Which modified base, when present at the wobble position of the anticodon, can base-pair with three different bases in the third codon position?
- A Pseudouridine
- B Inosine ✓
- C Dihydrouridine
- D Ribothymidine
Correct answer: B. Inosine
Explanation
Inosine (the nucleoside of hypoxanthine) occupies the wobble position of several anticodons, notably tRNA-Ala with anticodon 5'-IGC-3', and pairs with B, U or C at the third codon position, letting one tRNA read GCU, GCC and GCA. Standard Watson-Crick rules govern the first two codon positions strictly. Pseudouridine, dihydrouridine and ribothymidine occur elsewhere in tRNA structure and follow normal pairing specificity at the wobble position.
Reference: Lehninger Principles of Biochemistry, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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