Jeff Johnson is the director of the Mass Spectrometry lab. Jeff received his Ph.D. from The Scripps Research Institute under the mentorship of John Yates. Prior to joining the Krogan Lab at UCSF, Jeff was a Protein Chemistry postdoctoral fellow at Genentech, Inc. Expertise: global studies of post-translational modifications (particularly phosphorylation, ubiquitylation, and acetylation); pathway analysis.