2-O-(2-Aminoethyl)-myo-inositol 1,4,5-trisphosphate as a novel ligand for conjugation: physicochemical properties and synthesis of a new Ins(1,4,5)P(3) affinity matrix.
2-O-(2-Aminoethyl)-Ins(1,4,5)P(3), (5), a novel derivative of the Ca(2+)-mobilising second messenger d-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)], was synthesised from myo-inositol. 5 was found to be a potent mobiliser of intracellular Ca(2+), and an Ins(1,4,5)P(3) affinity matrix synthesised from 5 was effective at selectively binding N-terminal fragments of the Ins(1,4,5)P(3) receptor containing the intact Ins(1,4,5)P(3) binding site. The microprotonation scheme for 5 was resolved and the related constants were determined in comparison with Ins(1,4,5)P(3) and another reactive Ins(1,4,5)P(3) analogue 1-O-(2-aminoethyl-1-phospho)-Ins(4,5)P(2), (2a), by potentiometric and NMR titration methods. The (31)P and (1)H NMR titration curves for compound 5 and Ins(1,4,5)P(3) are remarkably close, indicating analogous acid-base properties and intramolecular interactions for the two compounds. The 1-phosphate-modified Ins(1,4,5)P(3) derivative 2a, on the contrary, behaves as a bisphosphorylated rather than a trisphosphorylated inositol. Thus, 5 is a new reactive Ins(1,4,5)P(3) analogue of considerable potential for investigation of the chemical biology of Ins(1,4,5)P(3)-mediated cellular signalling.
Riley
Andrew M
AM
Wolfson Laboratory of Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath BA2 7AY, UK.
Dozol
Helene
H
Spiess
Bernard
B
Potter
Barry V L
BV
D000588:Amines / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods; D002118:Calcium / Q000737:chemistry / Q000378:metabolism; D002846:Chromatography, Affinity; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007294:Inositol / Q000737:chemistry; D015544:Inositol 1,4,5-Trisphosphate / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry; D007700:Kinetics; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods; D010759:Phosphorus Isotopes; D011199:Potentiometry; D011485:Protein Binding; D011522:Protons
D000588:Amines; D008024:Ligands; D010759:Phosphorus Isotopes; D011522:Protons; D007294:Inositol; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium