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myo-Inositol monophosphatase is an activated target of calbindin D28k.

Berggård, Tord LU ; Szczepankiewicz, Olga LU ; Thulin, Eva LU and Linse, Sara LU (2002) In Journal of Biological Chemistry 277(44). p.41954-41959
Abstract
Calbindin D28k (calbindin) is a member of the calmodulin superfamily of Ca2+ -binding proteins. An intracellular target of calbindin was discovered using bacteriophage display. Human recombinant calbindin was immobilized on magnetic beads and used in affinity purification of phage-displayed peptides from a random 12-mer peptide library. One sequence, SYSSIAKYPSHS, was strongly selected both in the presence of Mg2+ and in the presence of Ca2+. Homology search against the protein sequence data base identified a closely similar sequence, ISSIKEKYPSHS, at residues 55-66 in myo-inositol-1(or 4)-monophosphatase (IMPase, EC 3.1.3.25), which constitute a strongly conserved, and exposed region in the 3D structure. IMPase is a key enzyme in the... (More)
Calbindin D28k (calbindin) is a member of the calmodulin superfamily of Ca2+ -binding proteins. An intracellular target of calbindin was discovered using bacteriophage display. Human recombinant calbindin was immobilized on magnetic beads and used in affinity purification of phage-displayed peptides from a random 12-mer peptide library. One sequence, SYSSIAKYPSHS, was strongly selected both in the presence of Mg2+ and in the presence of Ca2+. Homology search against the protein sequence data base identified a closely similar sequence, ISSIKEKYPSHS, at residues 55-66 in myo-inositol-1(or 4)-monophosphatase (IMPase, EC 3.1.3.25), which constitute a strongly conserved, and exposed region in the 3D structure. IMPase is a key enzyme in the regulation of the activity of the phosphatidyl inositol signaling pathway. It catalyzes the hydrolysis of myo-inositol-1(or 4)-monophosphate to form free myo-inositol, maintaining a supply that represents the precursor for inositol phospholipid second messenger signaling systems. Fluorescence spectroscopy showed that isolated calbindin and IMPase interact with an apparent equilibrium dissociation constant, KD, of 0.9 mM. Both apo and Ca2+-bound calbindin was found to activate IMPase up to 250-fold, depending on the pH and substrate concentration. The activation is most pronounced at conditions which otherwise lead to a very low activity of IMPase, i.e. at reduced pH and at low substrate concentration. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Biological Chemistry
volume
277
issue
44
pages
41954 - 41959
publisher
ASBMB
external identifiers
  • wos:000178985300084
  • scopus:0036829514
ISSN
1083-351X
DOI
10.1074/jbc.M203492200
language
English
LU publication?
yes
id
9ba0e45f-9885-4838-906f-bdd0919d123c (old id 109926)
date added to LUP
2007-06-29 08:56:32
date last changed
2017-11-05 03:32:44
@article{9ba0e45f-9885-4838-906f-bdd0919d123c,
  abstract     = {Calbindin D28k (calbindin) is a member of the calmodulin superfamily of Ca2+ -binding proteins. An intracellular target of calbindin was discovered using bacteriophage display. Human recombinant calbindin was immobilized on magnetic beads and used in affinity purification of phage-displayed peptides from a random 12-mer peptide library. One sequence, SYSSIAKYPSHS, was strongly selected both in the presence of Mg2+ and in the presence of Ca2+. Homology search against the protein sequence data base identified a closely similar sequence, ISSIKEKYPSHS, at residues 55-66 in myo-inositol-1(or 4)-monophosphatase (IMPase, EC 3.1.3.25), which constitute a strongly conserved, and exposed region in the 3D structure. IMPase is a key enzyme in the regulation of the activity of the phosphatidyl inositol signaling pathway. It catalyzes the hydrolysis of myo-inositol-1(or 4)-monophosphate to form free myo-inositol, maintaining a supply that represents the precursor for inositol phospholipid second messenger signaling systems. Fluorescence spectroscopy showed that isolated calbindin and IMPase interact with an apparent equilibrium dissociation constant, KD, of 0.9 mM. Both apo and Ca2+-bound calbindin was found to activate IMPase up to 250-fold, depending on the pH and substrate concentration. The activation is most pronounced at conditions which otherwise lead to a very low activity of IMPase, i.e. at reduced pH and at low substrate concentration.},
  author       = {Berggård, Tord and Szczepankiewicz, Olga and Thulin, Eva and Linse, Sara},
  issn         = {1083-351X},
  language     = {eng},
  number       = {44},
  pages        = {41954--41959},
  publisher    = {ASBMB},
  series       = {Journal of Biological Chemistry},
  title        = {myo-Inositol monophosphatase is an activated target of calbindin D28k.},
  url          = {http://dx.doi.org/10.1074/jbc.M203492200},
  volume       = {277},
  year         = {2002},
}