Chemistry: molecular biology and microbiology – Measuring or testing process involving enzymes or... – Involving viable micro-organism
Patent
1994-02-07
1998-12-08
Fitzgerald, David L.
Chemistry: molecular biology and microbiology
Measuring or testing process involving enzymes or...
Involving viable micro-organism
435325, 43525411, 435 691, 435 721, 435 6, 530350, 530395, 514 2, 514 8, C12A 102, C07K 14705
Patent
active
058467572
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to molecular biology and pharmacology. More particularly, the invention relates to calcium channel compositions and methods of making and using the same.
BACKGROUND OF THE INVENTION
Calcium channels are membrane-spanning, multi-subunit proteins that allow controlled entry of Ca.sup.2+ ions into cells from the extracellular fluid. Cells throughout the animal kingdom, and at least some bacterial, fungal and plant cells, possess one or more types of calcium channel.
The most common type of calcium channel is voltage dependent. "Opening" of a voltage-dependent channel to allow an influx of Ca.sup.2+ ions into the cells requires a depolarization to a certain level of the potential difference between the inside of the cell bearing the channel and the extracellular medium bathing the cell. The rate of influx of Ca.sup.2+ into the cell depends on this potential difference. All "excitable" cells in animals, such as neurons of the central nervous system (CNS), peripheral nerve cells and muscle cells, including those of skeletal muscles, cardiac muscles, and venous and arterial smooth muscles, have voltage-dependent calcium channels.
Multiple types of calcium channels have been identified in mammalian cells from various tissues, including skeletal muscle, cardiac muscle, lung, 51:367-384 and Hess, P. (1990) Ann. Rev. Neurosci. 56:337!. The different types of calcium channels have been broadly categorized into four classes, L-, T-, N-, and P-type, distinguished by current kinetics, holding potential sensitivity and sensitivity to calcium channel agonists and antagonists.
Calcium channels are multisubunit proteins. For example, rabbit skeletal muscle calcium channel contains two large subunits, designated .alpha..sub.1 and .alpha..sub.2, which have molecular weights between about 130 and about 200 kilodaltons ("kD"), and one to three different smaller subunits of less than about 60 kD in molecular weight. At least one of the larger subunits and possibly some of the smaller subunits are glycosylated. Some of the subunits are capable of being phosphorylated. The .alpha..sub.1 subunit has a molecular weight of about 150 to about 170 kD when analyzed by sodium dodecylsulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) after isolation from mammalian muscle tissue and has specific binding sites for various 1,4-dihydropyridines (DHPs) and phenylalkylamines. Under non-reducing conditions (in the presence of N-ethylmaleimide), the .alpha..sub.2 subunit migrates in SDS-PAGE as a band corresponding to a molecular weight-of about 160-190 kD. Upon reduction, a large fragment and smaller fragments are released. The .beta. subunit of the rabbit skeletal muscle calcium channel is a phosphorylated protein that has a molecular weight of 52-65 kD as determined by SDS-PAGE analysis. This subunit is insensitive to reducing conditions. The .gamma. subunit of the calcium channel, which is not observed in all purified preparations, appears to be a glycoprotein with an apparent molecular weight of 30-33 kD, as determined by SDS-PAGE analysis.
In order to study calcium channel structure and function, large amounts of pure channel protein are needed. Because of the complex nature of these multisubunit proteins, the varying concentrations of calcium channels in tissue sources of the protein, the presence of mixed populations of calcium channels in tissues, difficulties in obtaining tissues of interest, and the modifications of the native protein that can occur during the isolation procedure, it is extremely difficult to obtain large amounts of highly purified, completely intact calcium channel protein.
Characterization of a particular type of calcium channel by analysis of whole cells is severely restricted by the presence of mixed populations of different types of calcium channels in the majority of cells. Single-channel recording methods that are used to examine individual calcium channels do not reveal any information regarding the molecular structure or biochemical composition of the chann
REFERENCES:
patent: 4675285 (1987-06-01), Clark et al.
patent: 4788135 (1988-11-01), Davis et al.
patent: 4912202 (1990-03-01), Campbell et al.
patent: 4954436 (1990-09-01), Froehner et al.
patent: 5024939 (1991-06-01), Gorman
patent: 5051403 (1991-09-01), Miljanich et al.
patent: 5189020 (1993-02-01), Miljanich et al.
patent: 5264371 (1993-11-01), Miljanich et al.
patent: 5386025 (1995-01-01), Jay et al.
patent: 5407820 (1995-04-01), Ellis et al.
patent: 5424218 (1995-06-01), Miljanich et al.
Brust et al., "Human Neuronal Voltage-Dependent Calcium Channels: Studies on Subunit Structure and Role in Channel Assembly", Neuropharmacology 32(11):1089-1102 (1993).
Williams, et al., "Structure and Functional Characterization of Neuronal .alpha..sub.1E Calcium Channel Subtypes," J. Biol. Chem. 269(35):22347-22357 (1994).
Soong et al., "Structure and Functional Expression of a Member of the Low Voltage-Activated Calcium Channel Family", Science 260:1133-1136 (1993).
Powers, et al., "Assignment of the human gene for the .alpha..sub.1 subunit of the cardiac DHP-sensitive Ca.sup.2+ channel (CCHL1A1) to Chromosome 12p12-pter," Genomics, 10: 835-839 (1991).
Kim, et al., "IgG from patients with Lambert-Eaton syndrome blocks voltage-dependent calcium channels," Science, 239: 405-408 (1988).
Claudio, et al., "Genetic reconstitution of functional acetylcholine receptor channels in mouse fibroblasts," Science, 238: 1688-1694 (1987).
Tanabe, et al., "Primary structure of the receptor for calcium channel blockers from skeletal muscle," Nature, 328: 313-318 (1987).
Nakayama, et al., "Purification of a putative Ca.sup.2+ channel protein from rabbit skeletal muscle," J.Biol.Chem., 262: 6572-6576 (1987).
Vaghy, et al., "Identification of a novel 1,4-dihydropyridine-and phenylalkylamine-binding polypeptide in calcium channel preparations," J.Biol.Chem., 262(29): 14337-14342 (1987).
Leung, et al., "Structural characterization of the 1,4-dihydropyridine receptor of the voltage-dependent Ca.sup.2+ channel from rabbit skeletal muscle," J.Biol.Chem., 262(17): 7943-7946 (1987).
Sharp, et al., "Identification and characterization of the dihydropyridine-binding subunit of the skeletal muscle dihydropyridine receptor," J.Biol.Chem., 62(25): 12309-12315 (1987).
Takahashi, et al., "Subunit structure of dihydropyridine-sensitive calcium channels from skeletal muscle," Proc.Natl.Acad.Sci. (USA), 84: 5478-5482 (1987).
Morton et al., "Monoclonal antibody identifies a 200-kDA subunit of the dihydropyridine-sensitive calcium channel," J.Biol.Chem., 262(25): 11904-11907 (1987).
Barhanin, et al., "The calcium channel antagonists receptor from rabbit skeletal muscle: reconstitution after purification and subunit characterization," Eur.J.Biochem., 164: 525-531 (1987).
Sieber, et al., "The 165-kDa peptide of the purified skeletal muscle dihydropyridine receptor contains the known regulatory sites of the calcium channel," Eur.J.Biochem., 167: 117-122 (1987).
Lang, et al., "The effect of myasthenic syndrome antibody on presynaptic calcium channels in the mouse," J.Physiol., 390: 257-270 (1987).
Curran and Morgan, "Barium modules c-fos expression and post-translational modification," Proc.Natl.Acad.Sci., 83: 3521-8524 (1986).
Fisch, et al., "c-fos sequences necessary for basal expression and induction by epidermal growth factor, 12-O-tetradecanoyl phorbol--13-acetate, and the calcium inophore," Mol.Cell.Biol., 7(10): 3490-3502 (1987).
Noda, et al., "Existence of distinct sodium channel messenger RNAs in rat brain," Nature, 320: 188-192 (1986).
Noda, et al., "Expression of functional sodium channels from cloned cDNA," Nature, 322: 826-828 (1986).
Mierendorf, et al., "Gene isolation by screening kgtll libraries with antibodies," Methods in Enz., 152: 458-469 (1986).
Gustin, et al., "Ion channels in yeast," Science, 233: 1195-1197 (1986).
Striessnig, et al., "Photoaffinity labelling of the phenylalkylamine receptor of the skeletal muscle transverse-tubule calcium channel," FEBS Letters, 212(2):247-253 (1987)
Brenner Robert
Ellis Steven B.
Feldman Daniel H.
Harpold Michael M.
McCue Ann F.
Fitzgerald David L.
Seidman Stephanie L.
SIBIA Neurosciences Inc.
LandOfFree
Human calcium channel .alpha..sub.1, .alpha..sub.2, and .beta. s does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Human calcium channel .alpha..sub.1, .alpha..sub.2, and .beta. s, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Human calcium channel .alpha..sub.1, .alpha..sub.2, and .beta. s will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-176076