Research Interests

Most of my career has been devoted to studying the role of protein phosphorylation in cell regulation and have contributed to several areas of this field. I defined how glycogen synthase is regulated by multisite phosphorylation, dissected the PI 3-kinase-dependent signaling pathway by which insulin activates glycogen synthase, and identified the unique glucosyl-tyrosine residue in glycogenin by which this "primng" protein is linked covalently to glycogen. I also elucidated the subunit composition of phosphorylase kinase and how it is regulated by calmodulin and cyclic AMP-dependent phosphorylation. My laboratory purified and classified the major classes of serine/threonine-specific protein phosphatases, identified the calcium-calmodulin-dependent protein phosphatase and demonstrated that the sub-cellular localisation, specificity and regulation of protein phosphatase 1 is determined by its interaction with specific "targeting" subunits. My contributions to MAP kinase cascades include the characterisation of MAP kinase kinase 1 and its activation by c-Raf, the identification of the p38 MAP kinase-MAPKAP kinase-2 cascade and how it mediates the stress-induced phosphorylation of small heat shock proteins, and the demonstration that sustained activation of the classical MAP kinase cascade is required for neuronal differentiation. I also introduced a new method (KESTREL) for identifying the substrates of protein kinases. Currently, my laboratory is focused on signaling in the innate immune system and how it is regulated by the interplay between phosphorylation and ubiquitination.

Membership Type

International Member

Election Year

2008

Primary Section

Section 21: Biochemistry

Secondary Section

Section 42: Medical Physiology and Metabolism