Final answer:
Gene expression is a complex process regulated at multiple levels including epigenetic, transcriptional, and post-transcriptional, ensuring specific gene products are produced appropriately.
Step-by-step explanation:
Gene expression includes a wide range of mechanisms that are used by cells to increase or decrease the production of specific gene products. It is regulated at many levels, including epigenetic, transcriptional, nuclear shuttling, post-transcriptional, translational, and post-translational processes. Control of gene expression can begin with extracellular chemical signaling, influencing transcription which turns genes on or off. For example, transcription factors interact with DNA to control transcription, affecting protein levels.
Furthermore, gene expression is also controlled post-transcriptionally by regulating the rate of mRNA translation or degradation. Specific proteins and different noncoding RNA transcripts can target unwanted RNAs or proteins for degradation, altering the steady state of RNA or protein required for proper cell function. These processes are crucial for ensuring that the appropriate proteins are produced in correct amounts at the right times.