The inositol polyphosphate 5-phosphatases: traffic controllers, waistline watchers and tumour suppressors?

Abstract

Phosphoinositide signals regulate cell proliferation, differentiation, cytoskeletal rearrangement and intracellular trafficking. Hydrolysis of PtdIns(4,5)P2 and PtdIns(3,4,5)P3, by inositol polyphosphate 5-phosphatases regulates synaptic vesicle recycling (synaptojanin-1), hematopoietic cell function [SHIP1(SH2-containing inositol polyphosphate 5-phosphatase-1)], renal cell function [OCRL (oculocerebrorenal syndrome of Lowe)] and insulin signalling (SHIP2). We present here a detailed review of the characteristics of the ten mammalian 5-phosphatases. Knockout mouse phenotypes and underexpression studies are associated with significant phenotypic changes, indicating non-redundant roles, despite, in many cases, overlapping substrate specificity and tissue expression. The extraordinary complexity in the control of phosphoinositide signalling continues to be revealed.

• Authors: Megan V Astle, Kristy A Horan, Lisa M Ooms, Christina A Mitchell
• Journal: Biochemical Society symposium (Biochem Soc Symp) Issue 74 Pg. 161-81 ( 2007) ISSN: 0067-8694 [Print] England
• PMID: 17233589 (Publication Type: Journal Article, Review)

Chemical References

• Insulin
• Isoenzymes
• Phosphatidylinositol 3-Kinases
• Phosphoric Monoester Hydrolases
• Inositol Polyphosphate 5-Phosphatases
• INPP5D protein, human
• Inpp5d protein, mouse
• Inppl1 protein, mouse
• Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases

Topics

• Animals
• Humans
• Inositol Polyphosphate 5-Phosphatases
• Insulin (metabolism)
• Isoenzymes (chemistry, genetics, metabolism, physiology)
• Models, Biological
• Oculocerebrorenal Syndrome (enzymology, genetics)
• Phosphatidylinositol 3-Kinases (metabolism)
• Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases
• Phosphoric Monoester Hydrolases (chemistry, genetics, metabolism, physiology)
• Protein Structure, Tertiary
• Synaptic Vesicles (metabolism)