Possible binding sites for inositol 1,4,5-trisphosphate in macrophages.
We reported that an arylazide derivative of inositol 1,4,5-trisphosphate (InsP3) caused irreversible InsP3-induced Ca2+ release from saponin-permeabilized macrophages after photoirradiation. To determine the specific receptors for InsP3, presumably present on the endoplastic reticulum, we synthesized isotope-labeled arylazide derivatives of InsP3; InsP3 was coupled with p-azidobenzoyl [3H]beta-alanine (InsP3-[3H]AB beta A) or p-[125I]azidosalicyl beta-alanine (InsP3-[125I]AS beta A). We report here that three proteins may be associated with the Ca2+ releasing mechanism, in photoirradiated saponin-permeabilized macrophages and in the microsomal fraction.
Ishimatsu
T
T
Department of Biochemistry, Faculty of Dentistry, Kyushu University, Fukuoka, Japan.
Kimura
Y
Y
Ikebe
T
T
Yamaguchi
K
K
Koga
T
T
Hirata
M
M
D000818:Animals; D001386:Azides; D001665:Binding Sites; D002463:Cell Membrane Permeability / Q000187:drug effects; D006168:Guinea Pigs; D015544:Inositol 1,4,5-Trisphosphate; D007295:Inositol Phosphates / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism*; D010777:Photochemistry; D012503:Saponins / Q000494:pharmacology; D013403:Sugar Phosphates / Q000378:metabolism*
D001386:Azides; D007295:Inositol Phosphates; D012503:Saponins; D013403:Sugar Phosphates; D015544:Inositol 1,4,5-Trisphosphate