Question

C-Met is an oncogene that contributes to the development of certain cancers by triggering cell division and tumor growth. In a 2009 article, Yan and colleagues found regions in the 3' untranslated region of c-Met mRNA complementary to microRNA-1/206. In addition, higher levels of microRNA-1/206 were associated with slower cell proliferation. What is a likely explanation for the inverse correlation between microRNA-1/206 and cell proliferation?
A. MicroRNA-1/206 stabilizes c-Met mRNA, leading to enhanced translation.

B. MicroRNA-1/206 codes for a protein that directly binds to and inhibits c-Met protein.

C. MicroRNA-1/206 codes for a tumor suppressor protein that directly inhibits cell proliferation.

D. MicroRNA-1/206 targets c-Met mRNA for destruction via RISC.

Answer 1

Answer:

D. MicroRNA-1/206 targets c-Met mRNA for destruction via RISC.

Explanation:

microRNA's are non-coding RNA's, that is, they are not translated to proteins. MicroRNA-1/206 leads to gene silencing by 'tagging' the c-Met mRNA for cleavage by RISC proteins.

RISC: RNA-induced silencing complex is a ribonucleoprotein complex that leads to the incorporation of a single strand of micro RNA (or siRNA) that will bind to the targeted mRNA. The microRNA or siRNA strand will tag the targeted RNA for cleavage by proteins from the ribonucleoprotein. No translation will occur.