Gene expression is the biological process by which the information encoded in a gene is transcribed into messenger RNA (mRNA) and subsequently translated into a functional protein. It is a tightly regulated process governed by factors such as promoter strength, chromatin accessibility, and post-transcriptional regulatory elements, which collectively determine the level, timing, and tissue specificity of protein production. In biopharmaceutical manufacturing, controlling and maximizing recombinant gene expression is a central objective of cell line development, expression vector design, and upstream process optimization.
