Final answer:
Gene expression is the process by which the information in a gene is used to synthesize a functional protein, including transcription, translation, and post-transcriptional and post-translational modifications. It is regulated at multiple levels to ensure correct protein production.
Step-by-step explanation:
What is Gene Expression?
Gene expression refers to the entire process by which the information encoded in a gene is used to direct the synthesis of a functional gene product, typically a protein. This process includes transcription, where DNA is transcribed to produce messenger RNA (mRNA), and translation, where the mRNA is used as a template to synthesize a protein. However, gene expression also involves more than just these two steps; it includes post-transcriptional modifications such as splicing, editing, and transport of mRNA, as well as the post-translational modifications of proteins, which may affect protein folding, stability, and activity.
The regulation of gene expression ensures that proteins are produced at the right time and place and in the correct amounts, which is vital for the proper functioning of cells and organisms. Regulatory mechanisms can act at different stages, from epigenetic modifications that affect how DNA is packaged, to transcriptional controls that govern how a gene's DNA is transcribed, to post-translational modifications that alter protein function after it has been synthesized.