Document Detail


Turnover of inositol polyphosphate pyrophosphates in pancreatoma cells.
MedLine Citation:
PMID:  8382679     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
There is little information concerning the intracellular function of inositol 1,3,4,5,6-pentakis- and hexakisphosphate, despite their being the most abundant inositol polyphosphates. Current opinions that they play passive roles as antioxidants (Graf, E., Mahoney, J. R., Bryant, R. G., and Eaton, J. W. (1987) J. Biol. Chem. 259, 3620-3624) or "housekeeping" molecules (Berridge, M. J., and Irvine, R. F. (1989) Nature 341, 197-205) arises from belief in their metabolic lethargy. However, we have discovered that cell homogenates, incubated with 5 mM fluoride and 5 mM ATP, converted both inositol hexakisphosphate (Km = 2 +/- 0.5 microM, Vmax = 9 +/- 2 pmol/mg of protein/min) and inositol 1,3,4,5,6-pentakisphosphate (Km = 13 +/- 4 microM, Vmax = 11 +/- 5 pmol/mg of protein/min) to more polar products. These reactions were also observed in intact cells treated with 0.5-20 mM fluoride, and the precursor/product relationships were confirmed by comparing the effects of fluoride on cells differentially labeled with [3H]inositol in either short-term or pulse-chase protocols. The novel products were determined to be inositol pyrophosphates because of their relatively specific hydrolysis by tobacco pyrophosphatase and alkaline phosphatase. The pyrophosphates were metabolized rapidly by cell homogenates back to their pentakisphosphate and hexakisphosphate precursors. This endogenous pyrophosphatase activity was inhibited by up to 99% by 5 mM fluoride in vitro. In intact cells incubated with 10 mM fluoride, about 20% of the inositol 1,3,4,5,6-pentakisphosphate pool, and 50% of the inositol hexakisphosphate pool were each converted to pyrophosphate derivatives within 1 h.
Authors:
F S Menniti; R N Miller; J W Putney; S B Shears
Related Documents :
9695939 - Nitric oxide is formed in a subpopulation of rat pineal cells and acts as an intercellu...
21640519 - Impact of hypoxia on the metastatic potential of human prostate cancer cells.
4374199 - The effects of potassium, 5-hydrocytryptamine, adrenocorticotrophin and angiotensin ii ...
2996759 - Activation of the parathyroid hormone receptor-adenylate cyclase system in osteosarcoma...
200919 - Norepinephrine induces glial-specific enzyme activity in cultured plasma glioma cells.
6148909 - Nih conference. cyclic nucleotides: mediators of bacterial toxin action in disease.
24944809 - The differentiation effect of low-dose cytosine arabinoside is disturbed in pu.1-knockd...
12697379 - Diallylsulfide attenuates asbestos-induced genotoxicity.
25462079 - Over-expression of taexpb23, a wheat expansin gene, improves oxidative stress tolerance...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  The Journal of biological chemistry     Volume:  268     ISSN:  0021-9258     ISO Abbreviation:  J. Biol. Chem.     Publication Date:  1993 Feb 
Date Detail:
Created Date:  1993-03-26     Completed Date:  1993-03-26     Revised Date:  2013-02-11    
Medline Journal Info:
Nlm Unique ID:  2985121R     Medline TA:  J Biol Chem     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  3850-6     Citation Subset:  IM    
Affiliation:
Calcium Regulation Section, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Antimycin A / analogs & derivatives,  pharmacology
Diphosphates / metabolism*
Fluorides / pharmacology
Inositol Phosphates / chemistry,  metabolism*
Molecular Structure
Pancreatic Neoplasms
Phytic Acid / metabolism
Rats
Tumor Cells, Cultured
Type C Phospholipases / metabolism
Chemical
Reg. No./Substance:
0/Diphosphates; 0/Fluorides; 0/Inositol Phosphates; 11118-72-2/antimycin; 25663-09-6/inositol pentaphosphate; 642-15-9/Antimycin A; 83-86-3/Phytic Acid; EC 3.1.4.-/Type C Phospholipases

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Expression and phosphorylation of insulin receptor substrate 1 during rat liver regeneration.
Next Document:  Noradrenaline-activated heparin-sensitive Ca2+ entry after depletion of intracellular Ca2+ store in ...