In the roundworm C. elegans, the lin- 4 gene produces an RNA that forms a hairpin structure. One of the strands in the double- stranded region of lin- 4 hairpin RNA is complementary to the mRNA of a protein- coding gene, lin- 14. Predict the effect of expressing lin- 4 RNA during development.
A) The lin- 14 expression will rise when lin- 4 expression begins.
B) The lin- 4 RNA will bind the promoter of the lin- 14 gene, destroying the lin- 14 gene.
C) The lin- 4 RNA will bind to the enhancer of lin- 14, increasing lin- 14 transcription.
D) The lin- 14 expression will fall when lin- 4 expression begins.

Question

Quizplus · Accepted Answer

Since one of the strands of the lin-4 RNA is complementary to the mRNA of the lin-14 gene, it is likely that the lin-4 RNA will bind to and inhibit the translation of lin-14 mRNA, resulting in a decrease in lin-14 expression. This is supported by experimental evidence showing that lin-4 functions as a microRNA that acts to repress lin-14 expression during C. elegans development.

In the Roundworm C