The ordered progression of protein synthesis comprises three key stages. The first stage establishes the ribosomal complex at the messenger RNA start codon. Subsequent addition of amino acids to the growing polypeptide chain occurs in the second stage. The final stage involves the release of the completed polypeptide and dissociation of the ribosomal complex. For example, in eukaryotic cells, specific initiation factors are crucial for the binding of the small ribosomal subunit to the mRNA, while elongation factors mediate the tRNA entry and peptide bond formation. Termination occurs when the ribosome encounters a stop codon, signaling the release of the newly synthesized protein.
These processes are fundamental to all life forms, ensuring the accurate production of proteins essential for cellular structure and function. Their fidelity is paramount, as errors can lead to non-functional proteins and cellular dysfunction, potentially causing diseases. Historically, deciphering these stages has provided crucial insights into the central dogma of molecular biology and enabled the development of therapeutic interventions targeting protein synthesis in diseases such as bacterial infections and cancer.
