14 Studying Posttranslational Modifications in Yeast: Intracellular Proteins

Abstract

Publisher Summary This chapter focuses on intracellular proteins and post-translational modifications in yeast. For many intracellular proteins, after translation on the ribosome, further posttranslational modifications may occur. Such modifications may be important for the localization or activity of the protein and protein modification may also form part of a regulatory mechanism controlling the function of the particular polypeptide. Phosphorylation is probably the most frequently considered example of post-translational modification and the presence of a slower-migrating form of a protein is usually taken to indicate that a protein is most likely to be phosphorylated. However, phosphorylation is by no means the only post-translational modification to which yeast proteins may be subjected and well over 100 different modified amino acid residues may be found in specific proteins. The chapter surveys the most commonly occurring types of modification that may occur and describes techniques for identifying them and examining their function. It presents an overview of lipid modifications, prenylation, and ubiquitination. The chapter also summarizes the application of mass spectrometry to the study of protein modification because this has recently become one of the most powerful methods available for identifying post-translational modifications.