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ELife Nov 2012Human hepatitis B virus (HBV) infection and HBV-related diseases remain a major public health problem. Individuals coinfected with its satellite hepatitis D virus (HDV)...
Human hepatitis B virus (HBV) infection and HBV-related diseases remain a major public health problem. Individuals coinfected with its satellite hepatitis D virus (HDV) have more severe disease. Cellular entry of both viruses is mediated by HBV envelope proteins. The pre-S1 domain of the large envelope protein is a key determinant for receptor(s) binding. However, the identity of the receptor(s) is unknown. Here, by using near zero distance photo-cross-linking and tandem affinity purification, we revealed that the receptor-binding region of pre-S1 specifically interacts with sodium taurocholate cotransporting polypeptide (NTCP), a multiple transmembrane transporter predominantly expressed in the liver. Silencing NTCP inhibited HBV and HDV infection, while exogenous NTCP expression rendered nonsusceptible hepatocarcinoma cells susceptible to these viral infections. Moreover, replacing amino acids 157-165 of nonfunctional monkey NTCP with the human counterpart conferred its ability in supporting both viral infections. Our results demonstrate that NTCP is a functional receptor for HBV and HDV.DOI:http://dx.doi.org/10.7554/eLife.00049.001.
Topics: Amino Acid Sequence; Animals; Biological Transport; Cell Line; Gene Expression; Hepatitis B virus; Hepatitis Delta Virus; Hepatocytes; Humans; Liver; Molecular Sequence Data; Organic Anion Transporters, Sodium-Dependent; Peptides; Photochemical Processes; Primary Cell Culture; Protein Binding; Protein Structure, Tertiary; Receptors, Virus; Symporters; Taurocholic Acid; Tupaia; Viral Envelope Proteins; Virus Internalization
PubMed: 23150796
DOI: 10.7554/eLife.00049 -
Comparative Biochemistry and... Jan 2001The cloning of the avian Ang II receptor shows that it is molecularly close to the AT(1)-type mammalian receptor. However, pharmacological characterization in... (Comparative Study)
Comparative Study Review
The cloning of the avian Ang II receptor shows that it is molecularly close to the AT(1)-type mammalian receptor. However, pharmacological characterization in transfected cells shows that, even though the avian receptor is coupled to the phospholipase C, as is the AT(1), its profile of specificity towards antagonists appears different from that of the two angiotensin II mammalian receptor types. The fowl Ang II receptor mRNA is expressed in classical adult target organs for Ang II and, interestingly, also in endothelial cells, but not in vascular smooth muscle cells. In the endothelial cells, it may mediate the peculiar vasorelaxation effect of Ang II already reported in the chicken. The recent description of the expression pattern in the chick embryo shows that the avian Ang II receptor is expressed in many different mesenchymal tissues, a feature which is the signature of the AT(2) mammalian receptor. Altogether, these data imply that the avian Ang II receptor is an atypical receptor that cannot be readily classified as either of the two mammalian Ang II receptor types and, therefore, reinforce the evidence for another Ang II receptor in the avian class.
Topics: Amino Acid Sequence; Animals; Cloning, Molecular; Gene Expression; Humans; Mammals; Molecular Sequence Data; Poultry; RNA, Messenger; Receptors, Angiotensin; Sequence Homology, Amino Acid; Species Specificity
PubMed: 11137440
DOI: 10.1016/s1095-6433(00)00298-1 -
Arzneimittel-Forschung 1985The thyrotropin (TSH) receptor is an integral membrane protein which contains 2 subunits linked by a disulphide bridge. The A subunit (mol. wt. 50,000) is water soluble... (Review)
Review
The thyrotropin (TSH) receptor is an integral membrane protein which contains 2 subunits linked by a disulphide bridge. The A subunit (mol. wt. 50,000) is water soluble and forms the binding site for TSH, whereas the B subunit (mol. wt. 30,000) penetrates the lipid bilayer and probably forms the site for interaction with adenylate cyclase. Autoantibodies to the TSH receptor are found in the sera of patients with Graves' disease. The antibodies bind to the same region of the receptor's A subunit as TSH and usually act as TSH agonists, causing hyperthyroidism. Occasionally, TSH receptor autoantibodies are found which can act as TSH antagonists. Isoelectric focusing and binding studies indicate that these antibodies also bind to the same region of the receptor A subunit as TSH.
Topics: Animals; Autoantibodies; Humans; Hyperthyroidism; Isoelectric Focusing; Receptors, Cell Surface; Receptors, Thyrotropin
PubMed: 3006708
DOI: No ID Found -
Methods in Molecular Biology (Clifton,... 2016The estrogen receptors, ERα, ERβ, and GPER, mediate the effects of estrogenic compounds on their target tissues. Estrogen receptors are located in the tissues of the... (Review)
Review
The estrogen receptors, ERα, ERβ, and GPER, mediate the effects of estrogenic compounds on their target tissues. Estrogen receptors are located in the tissues of the female reproductive tract and breast as one would expect, but also in tissues as diverse as bone, brain, liver, colon, skin, and salivary gland. The purpose of this discussion of the estrogen receptors is to provide a brief overview of the estrogen receptors and estrogen action from perspectives such as the historical, physiological, pharmacological, pathological, structural, and ligand perspectives.
Topics: Animals; Disease Susceptibility; Estrogen Antagonists; Estrogen Receptor alpha; Estrogen Receptor beta; Estrogens; Evolution, Molecular; Female; Humans; Ligands; Male; Receptors, Estrogen; Receptors, G-Protein-Coupled; Risk Factors; Sex Factors; Signal Transduction
PubMed: 26585122
DOI: 10.1007/978-1-4939-3127-9_1 -
International Journal of Molecular... Dec 2020The vast majority of the literature on the aryl hydrocarbon receptor is concerned with its functions in xenobiotic detoxification. However, in the course of evolution,... (Review)
Review
The vast majority of the literature on the aryl hydrocarbon receptor is concerned with its functions in xenobiotic detoxification. However, in the course of evolution, this receptor had to have physiological (rather than toxicological) functions. Our aim was to review the aryl hydrocarbon receptor's role in the physiological functions involved in aging. This study was performed by searching the MEDLINE and Google Academic databases. A total of 34 articles were selected that focused specifically on the aryl hydrocarbon receptor and aging, the aryl hydrocarbon receptor and physiological functions, and the combination of both. This receptor's main physiological functions (mediated by the modulation of gene expression) were cell regeneration, the immune reaction, intestinal homeostasis, and cell proliferation. Furthermore, it was shown that the loss of this receptor led to premature aging. This process may be caused by the dysregulation of hematopoietic stem cells, loss of glucose and lipid homeostasis, increase in inflammation, and deterioration of the brain. We conclude that the aryl hydrocarbon receptor, apart from its well-established role in xenobiotic detoxication, plays an important role in physiological functions and in the aging process. Modulation of the signaling pathway of this receptor could be a therapeutic target of interest in aging.
Topics: Aging; Aging, Premature; Animals; Humans; Receptors, Aryl Hydrocarbon; Signal Transduction; Xenobiotics
PubMed: 33396477
DOI: 10.3390/ijms22010374 -
Methods in Molecular Biology (Clifton,... 2022Melatonin exerts its classical effects of relay of the circadian rhythm through two G protein-coupled receptors, MT1 and MT2. The functions attributed to melatonin are...
Melatonin exerts its classical effects of relay of the circadian rhythm through two G protein-coupled receptors, MT1 and MT2. The functions attributed to melatonin are so numerous that the action of this neurohormone should be through several protein targets or through new coupled biochemistry routes at its receptors. In order to better explore and understand these melatonin-dependent activities, we enlarged the functional pathways linked to the activation of the receptors in living system. Impedance has been shown to rely on the shape-shifting capacity of receptor-associated mechanisms. Those changes elicited by an agonist lead to changes in the actual shape of the cells, and thus to their electric conductivity. The impact of those changes onto the physiology of the cells is not completely understood from a mechanistic point of view, but the measure of these changes associated with various ligands at the melatonin receptor(s) might bring new information on melatonin-dependent cell reactivity. The following chapter is a detailed account of the way impedance can be measured in MT1-experssing cells.
Topics: Electric Impedance; Ligands; Melatonin; Receptor, Melatonin, MT1; Signal Transduction
PubMed: 36180694
DOI: 10.1007/978-1-0716-2593-4_25 -
Current Opinion in Virology Dec 2013The feline and human immunodeficiency viruses (FIV and HIV) target helper T cells selectively, and in doing so they induce a profound immune dysfunction. The primary... (Review)
Review
The feline and human immunodeficiency viruses (FIV and HIV) target helper T cells selectively, and in doing so they induce a profound immune dysfunction. The primary determinant of HIV cell tropism is the expression pattern of the primary viral receptor CD4 and co-receptor(s), such as CXCR4 and CCR5. FIV employs a distinct strategy to target helper T cells; a high affinity interaction with CD134 (OX40) is followed by binding of the virus to its sole co-receptor, CXCR4. Recent studies have demonstrated that the way in which FIV interacts with its primary receptor, CD134, alters as infection progresses, changing the cell tropism of the virus. This review examines the contribution of the virus-receptor interaction to replication in vivo as well as the significance of these findings to the development of vaccines and therapeutics.
Topics: Animals; Cats; Host-Pathogen Interactions; Immunodeficiency Virus, Feline; Receptors, CXCR4; Receptors, OX40; Receptors, Virus; T-Lymphocytes; Viral Tropism; Virus Attachment
PubMed: 23992667
DOI: 10.1016/j.coviro.2013.08.003 -
Progress in Molecular Biology and... 2013Based on the bioinformatic prediction, Zhang and colleagues discovered obestatin, a new 23-amino acid hormone from rat stomach extract encoded by the ghrelin gene.... (Review)
Review
Based on the bioinformatic prediction, Zhang and colleagues discovered obestatin, a new 23-amino acid hormone from rat stomach extract encoded by the ghrelin gene. Obestatin is present not only in the gastrointestinal tract, but also in the spleen, mammary gland, breast milk, and plasma. Obestatin appears to function as part of a complex gut-brain network whereby hormones and substances from the stomach, intestine and the brain about satiety or hunger. Given the current research regarding the effects of obestatin and its possible cognate receptor(s), this chapter provides the latest review of the physiological and pathological characteristics of this hormone and its possible receptor(s) in energy homeostasis and obesity.
Topics: Animals; Energy Metabolism; Ghrelin; Homeostasis; Humans; Obesity; Receptors, Ghrelin; Signal Transduction
PubMed: 23317783
DOI: 10.1016/B978-0-12-386933-3.00003-0 -
Frontiers in Neuroendocrinology Apr 1999
Review
Topics: Animals; Brain Chemistry; Humans; Receptors, Oxytocin
PubMed: 10328988
DOI: 10.1006/frne.1999.0178 -
Pakistan Journal of Biological Sciences... 2018Nicotine is regarded as the main active addictive ingredient in tobacco products driving continued tobacco abuse behavior (smoking) to the addiction behavior, whereas... (Review)
Review
Nicotine is regarded as the main active addictive ingredient in tobacco products driving continued tobacco abuse behavior (smoking) to the addiction behavior, whereas nicotinic acetylcholine receptors (nAChR) is the crucial effective apparatus or molecular effector of nicotine and acetylcholine and other similar ligands. Many nAChR subunits have been revealed to bind to either neurotransmitters or exogenous ligands, such as nicotine and acetylcholine, being involved in the nicotinic receptor signal transduction. Therefore, the nicotinic receptor signalling molecules and the receptor-ligand molecular interactions between nAChRs and their ligands are universally regarded as crucial mediators of cellular functions and drug targets in medical treatment and clinical diagnosis. Given numerous endeavours have been made in defining the roles of nAChRs in response to nicotine and other addictive drugs, this review focuses on studies and reports in recent years on the receptor-ligand interactions between nAChR receptors and ligands, including lipid-nAChR and protein-nAChR molecular interactions, relevant signal transduction pathways and their molecular mechanisms in the nicotinic receptor signalling systems. All the references were carefully retrieved from the PubMed database by searching key words "nicotine", "acetylcholine", "nicotinic acetylcholine receptor(s)", "nAChR*", "protein and nAChR", "lipid and nAChR", "smok*" and "tobacco". All the relevant referred papers and reports retrieved were fully reviewed for manual inspection. This effort intend to get a quick insight and understanding of the nicotinic receptor signalling and their molecular interactions mechanisms. Understanding the cellular receptor-ligand interactions and molecular mechanisms between nAChRs and ligands will lead to a better translational and therapeutic operations and outcomes for the prevention and treatment of nicotine addiction and other chronic drug addictions in the brain's reward circuitry.
Topics: Animals; Humans; Ligands; Nicotine; Receptors, Nicotinic; Signal Transduction; Tobacco Use Disorder
PubMed: 30221881
DOI: 10.3923/pjbs.2018.51.66