Method to measure the activation state of signaling pathways in cells
View Patent ↗The activity of multiple proteins in a single living cell, portion of a cell or in a group of cells is simultaneously measured by introducing reporter molecules into the cell(s) or a portion thereof, chemically modifying the reporter(s) by the enzyme of interest, terminating the modification reactions, removing the reporter(s) and modified reporter(s), and determining the amount of enzyme activity present by measuring or comparing the amount of reporter(s) and modified reporter(s) present. By performing a series of experiments at different time points, conditions, and varieties of cell types, a database is developed for molecular cellular mechanisms in health and disease states. By exposing cells to a variety of compounds data for drug development and screening is provided.
1. A method of detecting activities of a plurality of different enzymes in a cell, comprising:
introducing reporter molecules into the cell;
releasing the reporter molecules from the cell; and
detecting the reporter molecules to detect the activities of the plurality of different enzymes in the cell,
wherein the plurality of different enzymes comprises at least four enzymes.
2. The method of claim 1 , wherein the reporter molecules comprise at least one member selected from the group consisting of unaltered reporter molecules and altered reporter molecules.
3. The method of claim 1 , further comprising recording and tabulating the activities of the plurality of enzymes.
4. The method of claim 1 , further comprising exposing the cell to an external stimulus.
5. The method of claim 4 , wherein the external stimulus comprises a compound.
6. The method of claim 5 , wherein the compound is a polypeptide.
7. The method of claim 5 , further comprising recording and tabulating the activities of the plurality of enzymes, and further comprising compiling a map of cellular responses to the compound.
8. The method of claim 1 , wherein an auxiliary molecule that enters the cell is attached to at least one reporter molecule.
9. The method of claim 8 , wherein the auxiliary molecule is selected from the group consisting of a peptide and a peptide analog.
10. The method of claim 1 , wherein at least one reporter molecule comprises a label.
11. The method of claim 10 , wherein the label is selected from the group consisting of a fluorescent group, a stable isotope, a radioactive isotope, and biotin.
12. The method of claim 10 , wherein a first reporter molecule comprises a first label, and a second reporter molecule comprises a second label that is different than the first label.
13. The method of claim 1 , further comprising stopping reactions between the reporter molecules and the enzymes after releasing the reporter molecules.
14. The method of claim 13 , wherein the time between releasing the reporter molecules and stopping the reactions is less than 1 second.
15. The method of claim 14 , wherein the time is less than 33 milliseconds.
16. The method of claim 15 , wherein the time is less than 10 microseconds.
17. The method of claim 1 , wherein detecting further comprises separating the reporter molecules using at least one technique selected from the group consisting of electrophoresis, two-dimensional gel electrophoresis, microchromatography and flow cytometry.
18. The method of claim 1 , wherein detecting comprises using at least one technique selected from the group consisting of mass spectroscopy, fluorescence polarization spectroscopy, flow cytometry, yeast two-hybrid assay, morphological analysis, intercellular ion indicator activity, protein localization and affinity arrays.
19. The method of claim 1 , wherein detecting comprises detecting the reporter molecules on a microfluidics device.
20. The method of claim 1 , wherein detecting further comprises separating the reporter molecules on a microfluidics device.
21. The method of claim 1 , wherein the plurality of different enzymes comprises at least five enzymes.
22. The method of claim 1 , wherein the plurality of different enzymes comprises at least six enzymes.
23. The method of claim 1 , wherein the plurality of different enzymes comprises at least ten enzymes.
24. The method of claim 1 , wherein the cell comprises a portion of a cell.
25. The method of claim 1 , wherein the introducing comprises introducing at least one of the reporter molecules at a concentration of at most 10 micromolar.
26. The method of claim 1 , wherein the introducing comprises introducing at least one of the reporter molecules at a concentration of at most 1 micromolar.
27. The method of claim 1 , wherein the introducing comprises introducing at least one of the reporter molecules at a concentration of at most 100 nanomolar.
28. The method of claim 1 , further comprising diminishing or terminating a chemical reaction involving the reporter molecules using scavengers or inhibitors.
29. The method of claim 1 , further comprising labeling the reporter molecules and stopping a chemical reaction involving the reporter molecules by introducing an unlabeled reporter molecule.
30. The method of claim 1 , further comprising stopping a chemical reaction involving the reporter molecules before releasing the reporter molecules and unaltered reporter molecules from the cell.
31. The method of claim 28 , wherein the diminishing or terminating comprises photochemically introducing the scavenger or inhibitor from a caged scavenger or caged inhibitor.
32. The method of claim 1 , wherein detecting comprises quantifying the activities of at least three enzymes.
33. The method of claim 1 , wherein detecting comprises quantifying the activities of at least ten enzymes.