Final answer:
After miRNA is processed by Dicer, it associates with RISC to form the miRNA-RISC complex, which targets and degrades mRNA, regulating gene expression post-transcriptionally.
Step-by-step explanation:
After miRNA is diced, it associates with RISC (RNA-induced silencing complex) to produce the miRNA-RISC complex which targets mRNA for degradation. MicroRNAs (miRNAs) are small RNA molecules, approximately 21 nucleotides in length, that play critical roles in gene regulation. They are initially transcribed as longer pre-miRNAs that fold into stem-loop structures. These pre-miRNAs are then processed by the enzymes Drosha and Dicer to become mature miRNAs.
The mature miRNA gets incorporated into RISC, which then binds to complementary sequences in mRNA molecules leading to their degradation. This process is a component of post-transcriptional regulation, allowing cells to control gene expression efficiently. Understanding the functions of miRNAs and the miRNA-RISC complex is vital in biomedical research, including cancer therapeutics, where miRNAs like miR-21 are studied for their role in tumor progression.