Subcellular localization and some properties of the enzymes hydrolysing inositol polyphosphates in rat liver
Open Access
- 28 January 1985
- journal article
- Published by Wiley in FEBS Letters
- Vol. 180 (2), 150-154
- https://doi.org/10.1016/0014-5793(85)81061-9
Abstract
The hydrolysis of inositol [32P]trisphosphate (IP3) and inositol [32P]bisphosphate (IP2) has been examined in subcellular fractions of rat liver. IP3 was degraded by an enzyme located in the plasma membrane which did not degrade IP2. Cytosolic fractions were found to degrade both IP3 and IP3. The IP3 phosphatase activity of liver plasma membranes displayed a neutral pH optimum, was Mg2+ dependent and was not inhibited by high concentrations of Li+. Half‐maximal activity of the enzymes hydrolysing IP3 and IP2 was obtained with substrate concentrations in the range 1–2μM. The significance of these observations to the proposed Ca2+ ‐mobilizing role of IP3 is discussed.Keywords
This publication has 19 references indexed in Scilit:
- Inositol triphosphate: an intracellular messenger produced by Ca2+ mobilizing hormonesTrends in Biochemical Sciences, 1984
- Analysis of the metabolic turnover of the individual phosphate groups of phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate. Validation of novel analytical techniques by using 32P-labelled lipids from erythrocytesBiochemical Journal, 1984
- Breakdown of polyphosphoinositides and not phosphatidylinositol accounts for muscarinic agonist-stimulated inositol phospholipid metabolism in rat parotid glandsBiochemical Journal, 1983
- Changes in the levels of inositol phosphates after agonist-dependent hydrolysis of membrane phosphoinositidesBiochemical Journal, 1983
- The polyphosphoinositide phosphodiesterase of erythrocyte membranesBiochemical Journal, 1981
- Requirement for calcium ions in acetylcholine-stimulated phosphodiesteratic cleavage of phosphatidyl-myo-inositol 4,5-bisphosphate in rabbit iris smooth muscleBiochemical Journal, 1980
- LITHIUM AND BRAIN myo-INOSITOL METABOLISMPublished by Elsevier ,1978
- Assay of inorganic and organic phosphorus in the 0.1–5 nanomole rangeAnalytical Biochemistry, 1975
- Glutamate Dehydrogenase UV-AssayPublished by Elsevier ,1974
- A coupled optical enzyme assay for 5′-nucleotidaseAnalytical Biochemistry, 1967