Ralph Bradshaw
Position
Professor of Chemistry and Pharmaceutical Chemistry
Deputy Director, Mass Spectrometry Facility
Education
| Ph.D. | Biochemistry | 1966 | Duke University, Durham, NC |
| B.A. | Chemistry | 1962 | Colby College, Waterville, ME |
Work History
| 2006-Present: | Professor, Department of Pharmaceutical Chemistry, UCSF, San Francisco, CA, and Deputy Director, Mass Spectrometry Facility, UCSF, San Francisco, CA. |
| 2006-Present: | Professor Emeritus, Department of Physiology and Biophysics, College of Medicine, University of California, Irvine, Irvine, CA. |
| 2004-2005: | Parke-Davis Exchange Fellow, Department of Biochemistry, Cambridge University, Cambridge, United Kingdom. |
| 1997-2006: | Professor, Department of Physiology and Biophysics, and Department of Anatomy and Neurobiology, College of Medicine, University of California, Irvine, Irvine, CA. |
| 1993-1996: | Professor, Department of Biological Chemistry, College of Medicine, University of California, Irvine, Irvine, CA. |
| 1992-1993: | Alexander von Humboldt Senior Scientist, Max Planck Institute of Biochemistry, Department of Molecular Biology, Martinsried, Germany. |
| 1982-1993: | Professor and Chair, Department of Biological Chemistry, College of Medicine, University of California, Irvine, Irvine, CA. |
| 1977-1978: | Josiah Macy Faculty Scholar, Howard Florey Institute, University of Melbourne, Parkville, Victoria, Australia. |
| 1974-1982: | Professor, Department of Biological Chemistry, Washington University School of Medicine, St. Louis, MO. |
| 1972-1974: | Associate Professor, Department of Biological Chemistry, Washington University School of Medicine, St. Louis, MO. |
| 1969-1972: | Assistant Professor, Department of Biological Chemistry, Washington University School of Medicine, St. Louis, MO. |
| 1967-1969: | Senior Fellow and Acting Research Assistant Professor, Department of Biochemistry, University of Washington, Seattle, WA. |
| 1966-1967: | Research Associate, Department of Chemistry, Indiana University, Bloomington, IN. |
Research Interests
My overall research interests are related to the structure/function relationships of proteins. For many years, these have focused on two areas: eukaryotic signal transduction and co/post-translational processing of protein N-termini. More recently, many aspects of work in both areas have lead to a strong developing interest in the use of proteomic analyses, particularly those supported by mass spectrometric approaches.
An important segment of cell signaling is dependent on polypeptide growth factors and their receptors. Beginning with studies on nerve growth factor (NGF), fibroblast growth factor (FGF) and epidermal growth factor (EGF), all of which utilize receptor tyrosine kinases (RTKs), we have continually concentrated on the elements of each system that contribute to their well-appreciated neuronal responses. Over the years we have added to the understanding of both ligand receptor chemistries, particularly using various mutant cell lines and stably transfected chimeric receptors to define signaling responses. The application of quantitative phosphoproteomic analyses to several of our stably transfected PC12 cell paradigms bearing selectively mutated TrkA chimeras has better defined the serine/threonine phosphoproteome following 20 min of stimulation and better defined which responses are derived from which docking sites.. In addition, in collaboration with the Shokat Laboratory, we have also been focusing on the immediate targets of the TrkA kinase domain utilizing mutants that can utilize special ATP derivatives and bearing the same signaling alterations. We are now expanding these studies to determine the profile of Lys-acetylation and O-GlcNAc modification of Ser and Thr residues as an overlay study to the phosphoproteomic analysis. The techniques utilized in these studies will also be useful in other applications such as determining the basis of drug resistance in cancer and in the differentiation of stem cells.
The earliest modifications of proteins following the initiation of protein synthesis are N-terminal modifications that can be divided into three main groups: those that modify the α-amino group, those that modify the side chain of the N-terminal residue and those that involve proteolysis of one or more amino acids. There are more than three dozen such alterations, some of which are quite common and are essentially ubiquitous, and others that are quite rare. Similarly, some occur as co-translational events while others occur only later in the lifetime of the protein, after it is fully synthesized. We have focused on the removal of initiator methionine residues and the acetylation of the Nα-amino group (with or without the methionine) and have characterized some of the enzymes involved in different species. Defects in these modifications have been increasingly tied to various pathologies and form the basis for further investigations.
Select Publications
Biarc, J. , Chalkley, R.J., Burlingame, A.L., Bradshaw, R.A., Receptor Tyrosine Kinase Signaling: A Proteomic Perspective, Adv Enzyme Regulation, 51(1), 1-13 (2010). [Pubmed]
Bradshaw, R.A., An Introduction to Proteomics: Applications to Plant Biology in Plant Proteomics: Technologies, Strategies, and Applications, (G. Agarwal and R. Rakwal., eds), New York: John Wiley Publishers, 1-4 (2008).
Bradshaw, R.A., Medzihradszky, K.F., Ruperez, P., Oses-Prieto, J.A., and Burlingame, A.L., Post translational modifications: Identifying the wheat and sorting the chaff in Proceedings of 4th International Peptide Symposium (J. Wilce, ed.) Topic: Clinical Proteomics (2008).
Aurikko, J.P., Ruotolo, B.T., Grossman, J.G., Moncrieffe, M.C., Stephens, E., Leppanen, V.M., Robinson, C.V., Saarma, M., Bradshaw, R.A., and Blundell, T.L., Characterization of symmetric complexes of nerve growth factor and the ectodomain of the pan-neurotrophin receptor, p75NTR, J. Biol. Chem., 280(39), 33453-60 (2005). [Pubmed]
Nowroozi, N., Raffioni, S., Wang, T., Apostol, B.L., Bradshaw, R.A., and Thompson, L.M., Sustained ERK1/2 but not STAT1 or 3 activation is required for thanatophoric dysplasia phenotypes in PC12 cells, Human Molecular Genetics, 14(11), 1529-1538 (2005). [Pubmed]
Bradshaw, R.A., and Burlingame, A.L., From Proteins to Proteomics, IUBMB Life, 57(4-5), 267 - 272 (2005). [Pubmed]
Medzihradszky, K.F., Darula, Z., Perlson, E., Fainzilber, M., Chalkley, R.J., Ball, H., Greenbaum, D., Bogyo, M., Tyson, D.R., Bradshaw, R.A., and Burlingame, A.L., O-Sulfonation of serine and threonine - mass spectrometric detection and characterization of a new posttranslational modification in diverse proteins throughout the eukaryotes, Mol. Cell. Proteomics, 3(5), 429-440 (2004). [Pubmed]