Date of Award


Publication Type

Master Thesis

Degree Name



Chemistry and Biochemistry


Chemistry, Biochemistry.




Dual specificity phosphatases belong to the protein tyrosine phosphatase family of enzymes. These members have the ability to dephosphorylate both phosphotyrosine and phosphoserine/-phosphothreonine residues on the substrate proteins and have been found to be the regulators of critical cellular functions such as cell growth and cell cycle progression. The first dual specificity phosphatase was identified from vaccina virus. Later studies found homologues of VH1 in other organisms including yeast and humans. The human homologue, hYVH1, is a 36kDa enzyme containing a novel zinc finger domain. This research project was carried out as a first step towards the physiological characterization of this enzyme. In this project, we have identified the first associating protein of hYVH1 using affinity chromatography and mass spectrometry. The protein identified is Hsp70, a member of the heat shock family of proteins, known to get induced in response to cellular insults and to prevent apoptosis. Using substrate trapping mutants and two-dimensional gel electrophoresis we have identified unique spots which qualify to be the potential substrate of hYVH1. The identification and functional characterization of these potential substrates and interacting proteins will greatly enhance the elucidation of the physiological relevance of this evolutionary conserved phosphatase. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2005 .B88. Source: Masters Abstracts International, Volume: 44-03, page: 1366. Thesis (M.Sc.)--University of Windsor (Canada), 2005.