Answer :
Final answer:
Dicer cleaves RNAs for RISC binding, RISC targets mRNA for degradation, Argonaute is a component of RISC, and Drosha processes pri-miRNAs. None have helicase activity.
Explanation:
In the context of siRNA and miRNA post-transcriptional regulation, the functions of the proteins listed are as follows:
- dicer: This is an enzyme with endoribonuclease activity which cleaves long double-stranded RNAs and pre-miRNAs into short fragments, which are then involved in gene silencing when they bind to the RISC complex.
- RISC (RNA-induced Silencing Complex): A multi-protein complex that incorporates siRNAs or miRNAs, which then target complementary mRNA for degradation, thereby regulating gene expression.
- Argonaute: A family of proteins that are an essential component of RISC; they bind siRNAs and miRNAs and facilitate the gene-silencing process.
- Drosha: Part of the Microprocessor complex, it is responsible for processing pri-miRNAs into pre-miRNAs, which are then further processed by dicer into mature miRNAs.
None of the proteins listed have helicase activity to unwind double-stranded RNA; rather, they have different but specific roles in the RNA interference pathway.
