The instructions for making proteins are coded in the DNA of a cell. DNA, located in the cell’s nucleus (in eukaryotic cells), contains genes that serve as blueprints for protein synthesis. Each gene is a sequence of nucleotides, and its specific arrangement encodes information for building a particular protein.
This information is then transcribed into messenger RNA (mRNA), which carries the code from the nucleus to the ribosomes in the cytoplasm. Ribosomes are the sites where protein synthesis occurs, translating the mRNA sequence into an amino acid chain, which then folds into a functional protein. Thus, DNA plays a central role in guiding the cell’s processes and functions through protein production.