Smooth muscle and brain inositol 1,4,5-trisphosphate receptors are structurally and functionally similar.
Inositol 1,4,5-trisphosphate (InsP3) mediates smooth muscle contraction by mobilizing intracellular calcium release. In this study we provide a direct comparison of the smooth muscle and brain InsP3 receptors in terms of InsP3 binding and primary structure. The KD for InsP3 binding for both receptors was found to be essentially the same. Sequences from 11 bovine smooth muscle receptor tryptic peptides (120 amino acids) were identified in the mouse brain receptor with two substitutions attributable to species differences. A cDNA (approximately 1-kilobase) encoding a portion of the mouse smooth muscle InsP3 receptor was cloned and found to be identical to that reported for the brain receptor. This cDNA was used as a probe to demonstrate that the approximately 10-kilobase InsP3 receptor mRNA is detected in brain, smooth muscle, heart, liver, and kidney but was not detected in skeletal muscle or skin.
Marks
A R
AR
Laboratory of Molecular and Cellular Cardiology, Children's Hospital, Boston, Massachusetts.
Tempst
P
P
Chadwick
C C
CC
Riviere
L
L
Fleischer
S
S
Nadal-Ginard
B
B
D000595:Amino Acid Sequence; D000818:Animals; D001011:Aorta / Q000378:metabolism*; D001483:Base Sequence; D001921:Brain / Q000378:metabolism*; D015220:Calcium Channels; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates / Q000378:metabolism; D051379:Mice; D008969:Molecular Sequence Data; D009131:Muscle, Smooth, Vascular / Q000378:metabolism*; D015345:Oligonucleotide Probes; D009928:Organ Specificity; D010446:Peptide Fragments / Q000302:isolation & purification; D016133:Polymerase Chain Reaction / Q000379:methods; D011956:Receptors, Cell Surface / Q000235:genetics*; D018160:Receptors, Cytoplasmic and Nuclear; D012689:Sequence Homology, Nucleic Acid
D015220:Calcium Channels; D053496:Inositol 1,4,5-Trisphosphate Receptors; D007295:Inositol Phosphates; D015345:Oligonucleotide Probes; D010446:Peptide Fragments; D011956:Receptors, Cell Surface; D018160:Receptors, Cytoplasmic and Nuclear