title: Phosphoinositide 5-phosphatases: How do they affect tumourigenesis?
abstract: The activity of biological molecules is often affected by their phosphorylation state. Regulatory phosphorylation operates as a binary switch and is usually controlled by counteracting kinases and phosphatases. However, phosphatidylinositol (PtdIns) has three phosphorylation sites on its inositol ring. The phosphorylation status of PtdIns is controlled by multiple kinases and phosphatases with distinct substrate specificities, serving as a 'lipid code' or 'phosphoinositide code'. Class I phosphoinositide 3-kinase (PI3K) converts PtdIns(4,5)P₂ to PtdIns(3,4,5)P₃, which plays a pivotal role in signals controlling glucose uptake, cytoskeletal reorganization, cell proliferation and apoptosis. PI3K is pro-oncogenic, whereas phosphoinositide phosphatases that degrade PtdIns(3,4,5)P₃ are not always anti-oncogenic. Recent studies have revealed the unique characteristics of phosphoinositide 5-phosphatases.
authors.affiliation: Department of Biochemistry, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi 409-3898, Japan. keiji-miyazawa@umin.ac.jp
authors.forename: Keiji
authors.initials: K
authors.lastname: Miyazawa
mesh_terms: D000818:Animals; D017209:Apoptosis; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic / Q000378:metabolism*; D058534:Class I Phosphatidylinositol 3-Kinases / Q000378:metabolism; D003599:Cytoskeleton / Q000201:enzymology / Q000378:metabolism; D006801:Humans; D009363:Neoplasm Proteins / Q000378:metabolism; D009369:Neoplasms / Q000378:metabolism; D051059:PTEN Phosphohydrolase / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D015398:Signal Transduction; D000099182:Phosphoinositide 5-Phosphatases
chemical_list: D058534:Class I Phosphatidylinositol 3-Kinases; D009363:Neoplasm Proteins; D051059:PTEN Phosphohydrolase; D010744:Phosphoric Monoester Hydrolases; D000099182:Phosphoinositide 5-Phosphatases