Solubilization and separation of inositol 1,3,4,5-tetrakisphosphate- and inositol 1,4,5-trisphosphate-binding proteins and metabolizing enzymes in rat brain.
The two inositol phosphate-binding proteins, the Ins(1,4,5)P3 (InsP3) and Ins(1,3,4,5)P4 (InsP4) receptors, and the two particulate InsP3-metabolizing enzymes, InsP3 5-phosphatase and InsP3 3-kinase, were solubilized with detergent from rat cerebellar membranes. These four activities are shown to be distinct molecular species by separation using a variety of protein chromatographic steps. The pharmacology of the partially purified InsP4-binding site indicates that the binding has a high affinity and selectivity for InsP4 over InsP3. These results suggest the existence of a distinct specific InsP4-binding protein which may represent the receptor for this putative second messenger.
Theibert
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AB
Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
Supattapone
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S
Ferris
C D
CD
Danoff
S K
SK
Evans
R K
RK
Snyder
S H
SH
D000818:Animals; D001921:Brain / Q000201:enzymology / Q000378:metabolism*; D015220:Calcium Channels; D002462:Cell Membrane / Q000201:enzymology; D002531:Cerebellum / Q000201:enzymology / Q000378:metabolism; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D009928:Organ Specificity; D010744:Phosphoric Monoester Hydrolases / Q000302:isolation & purification* / Q000378:metabolism; D010770:Phosphotransferases / Q000302:isolation & purification* / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor); D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000302:isolation & purification* / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear; D012995:Solubility; D013379:Substrate Specificity
D015220:Calcium Channels; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates; D011956:Receptors, Cell Surface; D018160:Receptors, Cytoplasmic and Nuclear; C061107:inositol-1,3,4,5-tetrakisphosphate receptor; D010770:Phosphotransferases; D017853:Phosphotransferases (Alcohol Group Acceptor); C051038:Inositol 1,4,5-trisphosphate 3-kinase; C035215:inositol triphosphate phosphomonoesterase; D010744:Phosphoric Monoester Hydrolases