Purification and characterization of receptors for myoinositol trisphosphate and myoinositol tetrakis phosphate from Entamoeba histolytica.
The microsomal fraction from the log phase of Entamoeba histolytica cells contains Ins(1,4,5)P3 and Ins(1,3,4,5)P4 binding activity. The binding proteins/receptors for both Ins(1,4,5)P3 and Ins(1,3,4,5)P4 were purified and found to be specific for each ligand. The molecular masses for native proteins for InsP3 and InsP4 are 138 kDa and 130 kDa respectively having subunits of 69 kDa and 64 kDa respectively. That these proteins are associated with Ca2+ release was confirmed by including these proteins separately in proteoliposomes and adding InsP3 and InsP4 in both the cases.
Giri
B
B
Biochemistry Department, Bose Institute, Calcutta, India.
Das
R
R
Raha
S
S
Biswas
S
S
D000818:Animals; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D015220:Calcium Channels / Q000302:isolation & purification* / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D004748:Entamoeba histolytica / Q000737:chemistry*; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates / Q000378:metabolism; D008970:Molecular Weight; D021122:Protein Subunits; D011510:Proteolipids / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000302:isolation & purification* / Q000378:metabolism
D015220:Calcium Channels; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates; D021122:Protein Subunits; D011510:Proteolipids; D018160:Receptors, Cytoplasmic and Nuclear; C061107:inositol-1,3,4,5-tetrakisphosphate receptor; C020485:proteoliposomes; C081655:inositol-1,3,4,5-tetrakisphosphate; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium