Protein ubiquitylation is an important post-translational modification that has a critical role in regulating the life and death of cells. Ubiquitin transfer may rival phosphorylation in its importance, and it is important to unravel the molecular details of how ubiquitin is added to substrates. The focus of my laboratory is to understand the molecular processes that promote attachment of ubiquitin to proteins (ubiquitylation) and to uncover how other protein-protein interactions influence this process. Of particular interest to us is how multi-domain RING E3 ligases, of which there are several hundred in humans, specify substrates and regulate ubiquitin transfer. In this project, RING domain-containing proteins of interest as well as substrate proteins will be produced in E. coli, purified and characterized using biochemical and biophysical approaches, including elucidation of structures using x-ray crystallography. The aim of this project is to understand how ubiquitin transfer is regulated at the molecular level. The position offers opportunities to start a career in an important and topical area of biological research.