Proteinphosphatase
Protein phosphatases are enzymes that remove phosphate groups from phosphorylated amino acids on proteins, counteracting kinases and shaping cellular signaling networks. By reversing phosphorylation, they regulate processes such as cell cycle progression, metabolism, transcription, and responses to external stimuli. They act on serine, threonine, and in some cases tyrosine residues, depending on the enzyme.
Classification reveals major groups: protein tyrosine phosphatases (PTPs), serine/threonine phosphatases, and dual-specificity phosphatases (DUSPs) that can
Structure and regulation: PPP and PPM families contain catalytic subunits that require divalent metal ions and
Physiological role and examples: PP2A acts in MAPK and AKT signaling; calcineurin controls T-cell activation and
Clinical and research notes: Altered phosphatase activity is linked to cancer, diabetes, neurodegenerative, and autoimmune diseases;