Biomaterial Database

Cyclic ADP ribose activation of the ryanodine receptor is mediated by calmodulin. 1994

H C Lee, and R Aarhus, and R Graeff, and M E Gurnack, and T F Walseth

Department of Physiology, University of Minnesota, Minneapolis 55455.

Cyclic ADP-ribose (cADPR) is a newly identified nucleotide which can release calcium from a variety of cells, suggesting it is a messenger for mobilizing internal Ca2+ stores. Its cyclic structure has now been confirmed by X-ray crystallography. Available results are consistent with it being a modulator of Ca(2+)-induced Ca2+ release. Here we report that sea urchin egg microsomes purified by Percoll gradients lose sensitivity to cADPR, but the response can be restored by a soluble protein in the supernatant. Purification and characterization of the protein indicate that it is calmodulin. It appears to be sensitizing the Ca2+ release mechanism because caffeine and strontium, agonists of Ca(2+)-induced Ca2+ release, can also mimic calmodulin in conferring cADPR-sensitivity. Although evidence indicates that cADPR may be an activator of the ryanodine receptor, present results point to the importance of accessory proteins such as calmodulin in modulating its activity.

UI	MeSH Term	Description	Entries
D008861	Microsomes	Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	Microsome
D009124	Muscle Proteins	The protein constituents of muscle, the major ones being ACTINS and MYOSINS. More than a dozen accessory proteins exist including TROPONIN; TROPOMYOSIN; and DYSTROPHIN.	Muscle Protein,Protein, Muscle,Proteins, Muscle
D010063	Ovum	A mature haploid female germ cell extruded from the OVARY at OVULATION.	Egg,Egg, Unfertilized,Ova,Eggs, Unfertilized,Unfertilized Egg,Unfertilized Eggs
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002147	Calmodulin	A heat-stable, low-molecular-weight activator protein found mainly in the brain and heart. The binding of calcium ions to this protein allows this protein to bind to cyclic nucleotide phosphodiesterases and to adenyl cyclase with subsequent activation. Thereby this protein modulates cyclic AMP and cyclic GMP levels.	Calcium-Dependent Activator Protein,Calcium-Dependent Regulator,Bovine Activator Protein,Cyclic AMP-Phosphodiesterase Activator,Phosphodiesterase Activating Factor,Phosphodiesterase Activator Protein,Phosphodiesterase Protein Activator,Regulator, Calcium-Dependent,AMP-Phosphodiesterase Activator, Cyclic,Activating Factor, Phosphodiesterase,Activator Protein, Bovine,Activator Protein, Calcium-Dependent,Activator Protein, Phosphodiesterase,Activator, Cyclic AMP-Phosphodiesterase,Activator, Phosphodiesterase Protein,Calcium Dependent Activator Protein,Calcium Dependent Regulator,Cyclic AMP Phosphodiesterase Activator,Factor, Phosphodiesterase Activating,Protein Activator, Phosphodiesterase,Protein, Bovine Activator,Protein, Calcium-Dependent Activator,Protein, Phosphodiesterase Activator,Regulator, Calcium Dependent
D000246	Adenosine Diphosphate Ribose	An ester formed between the aldehydic carbon of RIBOSE and the terminal phosphate of ADENOSINE DIPHOSPHATE. It is produced by the hydrolysis of nicotinamide-adenine dinucleotide (NAD) by a variety of enzymes, some of which transfer an ADP-ribosyl group to target proteins.	ADP Ribose,Adenosine Diphosphoribose,ADP-Ribose,ADPribose,Adenosine 5'-Diphosphoribose,5'-Diphosphoribose, Adenosine,Adenosine 5' Diphosphoribose,Diphosphate Ribose, Adenosine,Diphosphoribose, Adenosine,Ribose, ADP,Ribose, Adenosine Diphosphate
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012617	Sea Urchins	Somewhat flattened, globular echinoderms, having thin, brittle shells of calcareous plates. They are useful models for studying FERTILIZATION and EMBRYO DEVELOPMENT.	Echinoidea,Sand-Dollar,Clypeasteroida,Sand Dollars,Clypeasteroidas,Dollar, Sand,Dollars, Sand,Echinoideas,Sand Dollar,Sand-Dollars,Sea Urchin,Urchin, Sea,Urchins, Sea
D013449	Sulfonamides	A group of compounds that contain the structure SO2NH2.	Sulfonamide,Sulfonamide Mixture,Sulfonamide Mixtures,Mixture, Sulfonamide,Mixtures, Sulfonamide