Biomaterial Database

Nicotine acts as a pharmacological chaperone to up-regulate human alpha4beta2 acetylcholine receptors. 2005

A Kuryatov, and J Luo, and J Cooper, and J Lindstrom

Department of Neuroscience, University of Pennsylvania Medical School, 217 Stemmler Hall 36th and Hamilton Walk, Philadelphia, Pennsylvania 19104, USA.

Human neuronal nicotinic acetylcholine receptor (AChR) alpha4 subunits and an alpha4 mutant (S247Falpha4) found in autosomal-dominant nocturnal frontal lobe epilepsy (ADNFLE) were expressed along with beta2 in permanently transfected tsA201 human embryonic kidney cell lines. Their sensitivity to activation, desensitization, and up-regulation by cholinergic ligands was investigated. Up-regulation after 3 to 24 h resulted primarily from an increase in assembly of AChRs from large pools of unassembled subunits, but up-regulation also resulted from a 5-fold increase in the lifetime of AChRs in the surface membrane. Up-regulation does not require current flow through surface membrane AChRs, because up-regulation occurs in the presence of the channel blocker mecamylamine and with the alpha4 mutant, which prevents nearly all AChR function. Both membrane-permeable ligands like nicotine and much less permeable quaternary amine cholinergic ligands can act as pharmacological chaperones within the endoplasmatic reticulum to promote the assembly of AChRs. Agonists are more potent pharmacological chaperones than antagonists, presumably because activated or desensitized conformations assemble more efficiently. Assembly intermediates are disrupted by solubilization in Triton X-100, but chemical cross-linking stabilizes a putative assembly intermediate approximately the size of an alpha4beta2alpha4beta2 tetramer.

UI	MeSH Term	Description	Entries
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D009538	Nicotine	Nicotine is highly toxic alkaloid. It is the prototypical agonist at nicotinic cholinergic receptors where it dramatically stimulates neurons and ultimately blocks synaptic transmission. Nicotine is also important medically because of its presence in tobacco smoke.	Nicotine Bitartrate,Nicotine Tartrate
D011978	Receptors, Nicotinic	One of the two major classes of cholinergic receptors. Nicotinic receptors were originally distinguished by their preference for NICOTINE over MUSCARINE. They are generally divided into muscle-type and neuronal-type (previously ganglionic) based on pharmacology, and subunit composition of the receptors.	Nicotinic Acetylcholine Receptors,Nicotinic Receptors,Nicotinic Acetylcholine Receptor,Nicotinic Receptor,Acetylcholine Receptor, Nicotinic,Acetylcholine Receptors, Nicotinic,Receptor, Nicotinic,Receptor, Nicotinic Acetylcholine,Receptors, Nicotinic Acetylcholine
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D003432	Cross-Linking Reagents	Reagents with two reactive groups, usually at opposite ends of the molecule, that are capable of reacting with and thereby forming bridges between side chains of amino acids in proteins; the locations of naturally reactive areas within proteins can thereby be identified; may also be used for other macromolecules, like glycoproteins, nucleic acids, or other.	Bifunctional Reagent,Bifunctional Reagents,Cross Linking Reagent,Crosslinking Reagent,Cross Linking Reagents,Crosslinking Reagents,Linking Reagent, Cross,Linking Reagents, Cross,Reagent, Bifunctional,Reagent, Cross Linking,Reagent, Crosslinking,Reagents, Bifunctional,Reagents, Cross Linking,Reagents, Cross-Linking,Reagents, Crosslinking
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D014162	Transfection	The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.	Transfections
D015854	Up-Regulation	A positive regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.	Receptor Up-Regulation,Upregulation,Up-Regulation (Physiology),Up Regulation
D017034	Epilepsy, Frontal Lobe	A localization-related (focal) form of epilepsy characterized by seizures which arise in the FRONTAL LOBE.	Frontal Epilepsy, Benign, Childhood,Frontal Lobe Epilepsy,Benign Frontal Childhood Epilepsy,Childhood Benign Frontal Epilepsy,Epilepsy, Anterior Fronto-Polar,Epilepsy, Benign Frontal, Childhood,Epilepsy, Cingulate,Epilepsy, Opercular,Epilepsy, Orbito-Frontal,Epilepsy, Supplementary Motor,Anterior Fronto-Polar Epilepsies,Anterior Fronto-Polar Epilepsy,Cingulate Epilepsies,Cingulate Epilepsy,Epilepsies, Anterior Fronto-Polar,Epilepsies, Cingulate,Epilepsies, Orbito-Frontal,Epilepsies, Supplementary Motor,Epilepsy, Anterior Fronto Polar,Epilepsy, Orbito Frontal,Frontal Lobe Epilepsies,Opercular Epilepsies,Opercular Epilepsy,Orbito-Frontal Epilepsies,Orbito-Frontal Epilepsy,Supplementary Motor Epilepsies,Supplementary Motor Epilepsy
D017830	Octoxynol	Nonionic surfactant mixtures varying in the number of repeating ethoxy (oxy-1,2-ethanediyl) groups. They are used as detergents, emulsifiers, wetting agents, defoaming agents, etc. Octoxynol-9, the compound with 9 repeating ethoxy groups, is a spermatocide.	Octylphenoxypolyethoxyethanols,Octoxinol,Octoxinols,Octoxynol-9,Octoxynols,Octylphenoxy Polyethoxyethanol,Triton X-100,Triton X-305,Triton X-45,Octoxynol 9,Polyethoxyethanol, Octylphenoxy,Triton X 100,Triton X 305,Triton X 45,Triton X100,Triton X305,Triton X45