Method for determination of the amount of either phosphotyrosine or phosphoserine in a protein

摘要

Traditional methods for measuring the phosphorylation state of cellular proteins have relied on 32P-orthophosphate labeling of cells in culture. The problems associated with radioactive isotopes have therefor prohibited phosphorylation studies on whole animals and humans. The present invention provides a unique technique that allows quantitative attachment of probes (e.g. fluorophors or biotin) to phospho-proteins and peptides by activating phospho-amino acids. the phosphorylation state of cellular proteins derived from human tissues can now be measured. This method can be used for early detection of cancer and diabetes and also for the identification of pharmaceutical agents.