Phosphorylation on demand

A new chemical biology tool that explores protein modifications is presented in a paper online.These results will provide the framework for determining the biological function of many important biochemical signals.

Proteins are frequently encoded with special amino acid tags to send them to different parts of the cell; alternatively, proteins can be modified with a variety of small chemical compounds that cause them to move within the cell.

Peter G. Schultz and colleagues now study this process in the case of the protein Pho4 by introducing an unusual amino acid to the protein chain inside the cell. This amino acid looks like serine – one of the amino acids that is used to make proteins – except it is blocked by a bulky group that can be removed with light. Once exposed, the serine can be phosphorylated, or modified by the addition of a phosphate group, by a normal cellular process. The authors discovered that, out of five important serines in the protein sequence, one has particular importance in controlling whether the protein is sent out of the nucleus or not. This technique offers a powerful new method for monitoring the function of phosphorylation.



Author contact:

Peter G. Schultz (The Scripps Research Institute, La Jolla, CA, USA)

Tel: +1 858 784 9300, Email: schultz@scripps.edu