Biogenesis of miRNA

The biogenesis of miRNA is the process by which tiny RNA molecules are made within cells to help regulate gene activity. It begins in the nucleus, where DNA is transcribed into a primary miRNA (pri-miRNA). This pri-miRNA is then processed by specialized enzymes into a shorter precursor miRNA (pre-miRNA). The pre-miRNA is exported to the cytoplasm, where further enzymes cut it into a mature miRNA duplex. One strand of this duplex is incorporated into a complex that binds to target messenger RNAs (mRNAs), controlling their stability or translation, thereby fine-tuning gene expression.