Final answer:
Gene expression in eukaryotic cells is regulated at multiple levels, including epigenetic, transcriptional, post-transcriptional, translational, and post-translational. This regulation begins with controlling DNA's accessibility and proceeds to intricate mechanisms that affect RNA processing and protein synthesis and function.
Step-by-step explanation:
Control of gene expression in eukaryotic cells occurs at multiple levels, which include epigenetic, transcriptional, post-transcriptional, translational, and post-translational levels. Starting with epigenetic control, gene expression is regulated by mechanisms that affect how tightly DNA is wound around histone proteins, impacting the accessibility of the DNA to transcription factors. Next, at the transcriptional level, gene expression is controlled by the binding of transcription factors and RNA polymerase to promoter and enhancer regions. Post-transcriptional regulation involves processes such as RNA splicing, nuclear shuttling, and RNA stability. The translational level involves the initiation and regulation of protein synthesis from mRNA, while post-translational control refers to modifications of the protein after synthesis that affect its function, stability, or localization.