Co-precipitation of Hog1 with Ptp3. A. Extracts from a wild-type yeast strain BY4741 (Research Genetics) expressing Myc-tagged Hog1 (Hog1-Myc), or Glutathione-S-transferase-tagged Ptp3 (GST-Ptp3), or both, were subjected to affinity purification of GST-Ptp3 with glutathione agarose beads followed by SDS-PAGE and immunoblot detection of Hog1-Myc (using mouse monoclonal α-Myc antibody 9E10), or GST-Ptp3 (using mouse monoclonal α-GST antibody B-14). Molecular mass markers (in kDa) are on the right. Details of the expression plasmids and purification methods can be found in Lee and Levin (2018). B. Ptp3 dissociates from Hog1 in response to arsenite treatment. Wild-type cells co-expressing Hog1-Myc and GST-Ptp3 were subjected to 1 mM arsenite (As[III]) for 5 min, 1 M sorbitol (Osm) for 5 min as a hyper-osmotic shock, or untreated (C). Extracts were processed as above for detection of Hog1 association with Ptp3.