Question

Which of the following RNA molecules is predicted to undergo internal base pairing to form a stable stem-loop structure.

a. 5'-----AUAUAUAUA--(any 5 bases)--UAUAUAUAU--- --3'-OH

b. 5'-----GCCGCCAG--(any 5 bases)--CUGGCGGC--- --3'-OH

c. 5'-----GAUGCUGC--(any 5 bases)--GAUGCUGC--- --3'-OH

d. 5'----AUAUAUAUA--(TATAAT)-- UAUAUAUAU--- --3'-OH

e. 5'----ATATATATA--(any 5 bases)--TATATAUTAT--- --3'-OH

Answer 1

The sequence 5'—GCCGCCAG—(any 5 bases)—CUGGCGGC——3'-OH is predicted to form a stable stem-loop structure because of internal base pairing between complementary cytosine and guanine bases.

Step-by-step explanation:

The RNA molecule predicted to form a stable stem-loop structure through internal base pairing is 5'—GCCGCCAG—(any 5 bases)—CUGGCGGC——3'-OH. This sequence contains complementary bases that are likely to form hydrogen bonds with each other, creating the stem-loop structure. In RNA molecules, cytosine (C) pairs with guanine (G), which allows for the formation of a double-stranded region within the single-stranded RNA molecule. The mentioned sequence has a segment (GCCGCC) that is complementary to another segment (GGCGGC) later in the sequence, providing the basis for the formation of the stem in a stem-loop structure. Other sequences either lack sufficient complementarity or have repeats that do not favor such internal base pairing.