Comparison of Ins(1,4,5)P3 receptors from rat cerebellum and bovine adrenal cortex.
Ins(1,4,5)P3 receptors in adrenal cortical and cerebellar membranes can be distinguished by their affinities for Ins(1,4,5)P3 as well as the potencies with which heparin and Mg2+ inhibit binding. We have found that the differences in Ins(1,4,5)P3 affinity and heparin inhibition are maintained upon receptor solubilization and purification. In contrast to this, heparin-agarose affinity purification of solubilized cerebellar receptors reduces the potency of Mg2+ inhibition to that in adrenal cortex. These results suggest that Ins(1,4,5)P3 receptors in adrenal cortex are structurally distinct from those in cerebellum. Monoclonal antibodies raised against C- and N-terminal regions of mouse cerebellar Ins(1,4,5)P3 receptors recognize 250-300-kDa proteins in both rat cerebellum and bovine adrenal cortex.
University Department of Pharmacology, Oxford, UK.
A M
AM
White
M A
MA
Varney
N
N
Maeda
K
K
Mikoshiba
S P
SP
Watson
D000302:Adrenal Cortex / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism*; D015220:Calcium Channels; D002417:Cattle; D006493:Heparin / Q000494:pharmacology; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism*; D053496:Inositol 1,4,5-Trisphosphate Receptors; D008274:Magnesium / Q000494:pharmacology; D008297:Male; D011092:Polyethylene Glycols; D051381:Rats; D017207:Rats, Sprague-Dawley; D011956:Receptors, Cell Surface / Q000302:isolation & purification / Q000378:metabolism*; D018160:Receptors, Cytoplasmic and Nuclear
D015220:Calcium Channels; D053496:Inositol 1,4,5-Trisphosphate Receptors; D011956:Receptors, Cell Surface; D018160:Receptors, Cytoplasmic and Nuclear; D011092:Polyethylene Glycols; D015544:Inositol 1,4,5-Trisphosphate; D006493:Heparin; D008274:Magnesium