Final answer:
MicroRNAs inhibit gene expression by binding to mRNA and preventing its translation into proteins, with the RNA-induced silencing complex assisting in this process.
Step-by-step explanation:
MicroRNAs (miRNAs) play a crucial role in the regulation of gene expression by targeting messenger RNA (mRNA) and inhibiting its function. Specifically, miRNAs block the expression of a specific gene product by binding to the mRNA and inhibiting translation. This means that miRNAs attach themselves to mRNA strands and prevent the ribosomes from translating the mRNA into proteins. The correct sequence of events as described in the RNA interference (RNAi) process is that miRNAs bind to mRNA with the help of a ribonucleoprotein complex known as the RNA-induced silencing complex (RISC). Once bound, the RISC-miRNA complex either degrades the target mRNA or inhibits its translation, effectively silencing the expression of the specific gene.