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Sandra S Rossie


  • Professor of Biochemistry
BCHM Room 315

Area of Expertise: Signal transduction and protein Ser/Thr phosphatases

Reversible phosphorylation is an important and common mechanism for regulating a wide variety of processes in response to incoming signals such as hormones and neurotransmitters, environmental changes or cell damage. In contrast to our knowledge of protein kinases and their roles in these processes, we know far less about protein phosphatases and their regulation. Protein phosphatase 5 (PP5) is a member of the largest Ser/Thr protein phosphatase family, with a unique N-terminal domain that inhibits PP5 activity and binds other proteins. PP5 has been implicated in signal transduction pathways controlling cell growth, differentiation and apoptosis, or programmed cell death. Little is known, however, about the physiological substrates for PP5 or how its activity is regulated.

We use biochemical and molecular approaches to define the role and regulation of PP5 in brain and other tissues. Projects include defining the structural basis for controlling PP5 activity and physiological regulators of PP5 activity. We are also using a proteomics approach to identify physiological substrates for PP5. We focus on the role of PP5 in neurons and in cancer cells, since the pathways in which PP5 may function are key players in neurodegenerative diseases and in tumor cell proliferation.

Awards & Honors

(1987) NIH Postdoctoral Fellowship. The University of Washington.

(1984) Pharmacological Sciences Training Fellowship. General Medical Sciences, NIH, The University of Chicago.

(2012) Outstanding Graduate Educator for Biochemistry. Purdue University Department of Biochemistry.

(2008) Fullbright Scholar. Fullbright Organization.

Selected Publications

Park, S., Scheffler, T., Rossie, S., & Gerrard, D. (2012). AMPK activity is regulated by calcium-mediated protein phosphatase 2A activity. Cell Calcium.

Bremmer, S., Hall, H., Martinez, J., Eissler, C., Hinrichsen, T., Parker, L., Hall, M., . . . Charbonneau, H. (2012). Cdc14 phosphatases preferentially dephosphorylate a subset of cyclin-dependent kinase (Cdk) sites containing phosphoserine. J. Biol. Chem. 287: 1662-1669. J. Biol. Chem., 287, 1662-1669. Retrieved from

Chatterjee, A., Wang, L., & Armstrong, D. (2010). Activated Rac1 GTPase translocates protein phosphatase 5 to the cell membrane and stimulates phosphatase activity in vitro. J. Biol. Chem., 285(6), 3872-3882. Retrieved from

Ham, B., Jayachandran, H., Yang, F., Jaitly, N., Polpitiya, A., Monroe, M., Wang, L., . . . Smith, R. (2010). Novel Ser/The protein phosphatase 5 (PP5) regulated targets during DNA damage indentified by proteomics analysis. J. Proteome. Res., 9(2), 945-953. Retrieved from

Sanchez-Ortiz, E., Hahm, B., & Armstrong, D. (2009). Protein phosphatase 5 protects neurons against amyloid-beta toxicity. J. Neurochem., 111(2), 391-402. Retrieved from

Ham, B., Yang, F., Jayachandran, H., Jaitly, N., Monroe, M., Gritsenko, M., Livesay, E., . . . Smith, R. (2008). The influence of sample preparation and replicate analyses on HeLa cell phosphoproteome coverage. J. Proteome Res., 7(6), 2215-2221. Retrieved from

Yang, F., Jaitly, H., Jayachandran, Q., Luo, M., Munroe, X., Du, M., Gritsenko, R., . . . Smith, R. (2007). Applying a targeted label-free approach using LC-MS AMT tags to evaluate changes in protein phosphorylation following phosphatase inhibition. J. Proteome Res., 6, 4489-4497. Retrieved from

Jayachandran, H., & Meisel, R. (2006). Cellular co-localization of protein phosphatase 5 and glucocorticoid receptors in rat brain. Brain Res., 1111, 11-Jan. Retrieved from

Messner, D., Romeo, C., & Boynton, A. (2006). Inhibition of PP2A, but not PP5, mediates p53 activation by low levels of okadaic acid in rat liver epithelial cells. J Cell Biochem, 99, 241-255. Retrieved from

Luo, Q., Tang, K., Yang, F., Elias, A., Shen, Y., Moore, R., Zhao, R., . . . Smith, R. (2006). More sensitive and quantitative proteomic measurements using very low flow rate poruous silica monolithic LC columns with electrospray ionization-mass spectrometry. J Proteome Res, 5(5), 1091-1097. Retrieved from