Frontispiece: Interrogating Protein Phosphatases with Chemical Activity Probes

The activities of protein phosphatases and protein kinases are responsible for maintaining the phosphoproteome. Although protein kinases have long enjoyed the spotlight, protein phosphatases have more recently been recognized as important signaling enzymes in both normal and disease physiology. This Minireview aims to highlight advances and opportunities for the development of chemical activity probes for protein phosphatases. For more details, see G. R. Casey and C. I. Stains on page 7810 ff.