Search for Physiological Substrates of Protein Tyrosine Phosphatase Epsilon in Mammary Tumor Cell Lines
Abstract
In this annual report we describe construction of substrate-trapping mutants of protein tyrosine phosphatase epsilon (PTPe) and the first round of experiments aimed at identification of physiological substrates of PTPe. Mutant PTPe molecules fused to glutathione-S-transferase (GST) were constructed, as were vectors for expressing mutant PTPe molecules in eukaryotic cells. GST fusion proteins could not be isolated in the absence of degradation; eukaryotic expression vectors, however, allowed us to appropriately express mutant PTPe molecules in transfected cells. Use of these mutants enabled us to establish that alpha subunits of voltage-gated potassium (Kv) channels are physiological substrates of PTPe and can be trapped by substrate-trapping mutants of PTPe. Furthermore, work described here provided a much-needed opportunity for calibrating and perfecting technical procedures for trapping substrates with these mutants. This experience will be implemented in future searches for PTPe substrates, searches guided by "educated guesses" of the identities of possible substrates of PTPe, or performed as general screens of mammary tumor cell lines.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1999
- Accession Number
- ADB262612
Entities
People
- Ari Elson
Organizations
- Weizmann Institute of Science