Introduction: Posttranslational Protein Modification

Our genome encodes about 20,000 genes, which are transcribed into mRNA and then translated into proteins. Proteins perform numerous biochemical functions and are central for all life processes, including metabolism, signal transduction, transcription, translation, cellular structural integrity, and cell movement. A common feature of all living organisms is the ability to adapt to and survive the changing environment. In order to respond to environmental changes, the proteins of a living organism, or the proteome, must change. New proteins may need to be synthesized to deal with an environmental stress. At the same time, existing proteins can undergo certain chemical modifications, commonly referred to as protein post-translational modifications (PTMs), which introduce structural changes in proteins and thus produce signal responses.