Structural basis for protein phosphatase 1 regulation and specificity

Department of Molecular Pharmacology, Physiology and Biotechnology, Brown University, Providence, RI, USA  Department of Chemistry, Brown University, Providence, RI, USA  Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA  Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, USA.
FEBS Journal (Impact Factor: 3.99). 01/2012; 280(2). DOI: 10.1111/j.1742-4658.2012.08509.x
Source: PubMed

ABSTRACT The ubiquitous serine/threonine protein phosphatase 1 (PP1) regulates diverse, essential cellular processes such as cell cycle progression, protein synthesis, muscle contraction, carbohydrate metabolism, transcription and neuronal signaling. However, the free catalytic subunit of PP1, while an effective enzyme, lacks substrate specificity. Instead, it depends on a diverse set of regulatory proteins (≥ 200) to confer specificity towards distinct substrates. Here, we discuss recent advances in structural studies of PP1 holoenzyme complexes and summarize the new insights these studies have provided into the molecular basis of PP1 regulation and specificity.

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