Questions tagged [receptor]
A receptor is a molecular target for a chemical signal such as a neurotransmitter, hormone, or drug. Binding of the signal to the receptor initiates or modulates behaviour in the receiving cell.
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Correlation between diffusion coefficient and ligand–receptor binding? [closed]
A cell may have different types of cellular receptor for different molecules. Furthermore, the same cellular receptor may bind many different molecules (competitive ligand binding). My question is:
a) ...
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Caffeine tolerance
I researched about caffeine tolerance and found out that regular consumption of coffe can build caffeine tolerance even if it's 1 cup per day, within few days or a week at most. Supposedly the body ...
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Why do protanopes see yellow and not green?
Why can protanopes see yellow but not green when the relative absorbance of these two colour waves by the m cone can be identical?
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Autoreceptor control of phasic and postsynaptic control of tonic signalling
I have read the following paragraph : "Whereas tonic DA signaling is affected by postsynaptic stimulation/blockade, phasic (transient) release of DA during dopaminergic cell bursting is modulated ...
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Are carrier proteins receptors?
I learnt about carrier proteins; how they bind a substrate/molecule, undergo a conformational change, and release the substrate/molecule on the other side of the membrane.
We can take Glucose ...
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T-Cell Receptor Receptor-Associated Immune Receptor Activation Motifs (ITAMs) Inconsistency
In reading the information associated with the cytoplasmic machinery of the T-Cell Receptor (TCR), the one tyrosine motif that is consistently mentioned is the receptor-associated immune receptor ...
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How are the receptors in the thalamus weakened/shut down during sleep?
During sleep, GABAergic inhibition of the thalamus occurs and along with that, it should "block" our senses. Are the receptors weakened, or completely shut down? If they are weakened, what ...
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At what cold temperature at thermoreceptors human feel pain (e.g. in fingers)?
I've tried web search but have not found that specific answer. As far as I know at least some people feel pain (e.g. in fingers) when exposed to cold for prolonged amounts of time. E.g. here ...
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Virus variant transmissibility: empirical data or spike protein shape?
Well first I am not in the field of Biology or Medical Sciences. Since these days we are waiting scientists to tell us if the Indian variant of SARS Cov 2 is more transmissible than the original virus,...
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How do G proteins move?
G proteins consist of an alpha subunit and a beta/gamma subunit. These proteins are involved in various cellular signalling process.
From what I have understood, the alpha and gamma subunits have ...
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Can caffeine act as viagra
Recently I studied that cAMP which is a 2° messenger can cause various physiolocal changes under the action of proper hormones. Now cAMP is degraded by phosphodiesterase and this ceases the actions. ...
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What differentiates bound antibodies from unbound ones?
When an antibody is bound to an antigen, it can then stimulate a FcR receptor on a phagocyte etc. to respond to the threat. What stops 'free' antibodies from spuriously activating an immune response?
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Why do GPCRs pass exactly 7 times through the cell membrane?
7-transmembrane domain receptors or GPCRs are one of the most common receptors in biology.
They can be found in eukaryotic cells.
What is the significance of the number 7 here: why does it pass ...
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Why is the SARS-CoV-2 target receptor ACE2 not endocytosed when bound physiologically?
The COVID-19 coronavirus SARS-CoV-2 enters cells by receptor-mediated endocytosis.
See, e.g. here.
Why doesn’t the enzyme ACE2 — SARS-CoV-2’s target receptor — undergo endocytosis when bound by its ...
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What degree of influence do SNPs have on activity of ligands at receptors?
I know that generally, evolution tends to evolve towards having some wiggle room in respect to effect of polymorphisms on binding of endogenous ligands, but with synthetic ligands, especially modern ...
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How do we know that selective agonists are indeed selective?
Suppose we know that compound X is a selective agonist of receptor Y, meaning that it binds only this receptor Y and no other. But how do we know this that it doesn't bind some another receptor? I ...
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In a skeletal muscle contraction, what happens after ACh binds to the nicotinic iontropic receptors on sarcolemma?
Does the bound ACh becomes unbound and then gets hydrolysed by acetylcholinerase?
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Can ACE2 receptors be syntesized? [duplicate]
I read that there are labs that can produces the spikes of the coronavirus. I wonder can they also synthesize ACE2 receptors or parts of them? If yes, can they be used as drugs?
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Time scale for cAMP-dependent pathway cascades
What is the time scale for cAMP-dependent pathway cascades that start at the level of ligand binding to a G-protein receptor and finish at the level of gene transcription regulation?
For example, when ...
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If a cell has two different GPCRs, how does the cell differentiate between the phosphorylation cascade caused by each?
In my biochem course, we learned that GPCR receptors trigger a phosphorylation cascade, with the end result being a large amplification of the signal in the form of cAMP. We never studied any ...
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Same target receptor different mechanism of action?
If different drugs have the same receptor as a target, does that imply that they have the same mechanism of action?
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Why is ACE2 not used as drug against covid? [closed]
Can ACE2 be produced and used as drug against covid? I read it is the receptor molecule. If it is in the organism the virus should bind to it and could not attack cells anymore? Is that right?
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Is it possible to make synthetic olfactory receptors?
Are there any electronic engineering technologies that allow people to make synthetic olfactory receptor that generate electrical impulses when exposed to certain proteins or molecules? If not, what ...
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Is the receptor of SARS-CoV-like viruses in bats still unknown?
A fairly detailed 2012 review (Whittaker et al.) on the Mechanisms of Coronavirus Cell Entry Mediated by the Viral Spike Protein noted that
SARS-CoV-like viruses have been isolated in bats. In this ...
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Is downregulation of neurological receptors fully reversible, i.e. complete upregulation and resensitization?
Are down/upregulation truly reciprocal mechanisms? After a binding ligand or agonist is removed, such as a prescription medication, is upregulation and resensitization able to occur to a level that ...
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Additive property of taste
It might be a dumb question to ask, but I find it confusing.
Is the perception of taste additive?
Or to be more precise, can two tasty food items combine to give a more delicious product?
For me, ...
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Are there pre-synaptic alpha 2 receptors in the post-ganglionic synapses of the heart?
Are there pre-synaptic alpha 2 receptors in the post-ganglionic synapses of the heart?
I haven't found any sources that clearly state whether they do or not. I'm also not sure if they exist in most ...
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How do receptors lose their sensitivity?
Recently, I learned that one of the causes of Type II diabetes is that insulin receptors on cell surfaces lose their sensitivity due to long-term high exposure to insulin (which occurs as a result of ...
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What structural features make a molecule a potent opioid receptor agonist?
For instance, take morphine. It is used as a baseline for measuring the potency of opioid agonists. Its structure looks like this:
But then, take heroin, around three times as potent, its structure ...
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What regulates cyclic AMP?
After reading a textbook chapter on GPCRs I am still confused by what regulates cAMP.
I took in my notes that cAMP is made by adenylyl cyclase and destroyed by cAMP phosphodiesterases (also another ...
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How can different ion channels of the same type have different cell responses?
The NMDA receptor is an ion channel and contributes to synaptic plasticity and memory. It is said that calcium ion flux through the receptor is critical for this mechanism. However, there are other ...
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Is there a data base, tool or method I can use to find out which of my genes code for cytokine receptors?
I have a list of over 600 differentially expressed genes from my single cell RNA seq data analyses. I want to proceed to find out which of my genes code for cytokine receptors so that I can show on a ...
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Influenza infections and drug design
Why is the neuraminidase used as a target for drugs against influenza virus instead of haemagglutinin? Is there some basic reason that this will make a more effective drug?
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James Allison's T-cell discovery technique
The excerpt on Wired magazine of The Breakthrough by Charles Graeber has the following description of how James Allison found the T-cell receptor.
Suddenly it seemed so obvious: If Allision could ...
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Is there a reason for the lack of full RTK structures?
Bocharov et al. (2013) write that
As there are no structures of full-length RTKs [receptor tyrosine kinases], we do not fully understand how different domains function together to mediate signal ...
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How long does it take for a blocked dopamine receptor to be broken down by the body?
Do the blocked dopamine receptors get broken down by the body and if so how often ?
In other words how long does it take for the dopamine receptors blocked by irreversible dopamine antagonists to ...
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Does anyone know of any resources that detail an extensive number of receptor types, their effects, and signalling pathways?
In a similar manner to this Wikipedia page, although I am not too concerned about the localisation of the receptor, or any known ligands, as I can already access this knowledge easily.
https://en.m....
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Why inhbition of RTK will not help in a case of mutant EGF?
I was given the following as an example for a quiz question but i don't understand the answer. Any help will be most welcome:
Question: Iressa is a Tyrosine Kinase Inhibitor. As a young oncologe, to ...
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What is the purpose of the viscous gel in the Pacinian corpuscle?
I have read that 'when the stimulus (in this case pressure) is constantly applied, the gel repositions itself to prevent the formation of an action potential'. I don't really understand what this ...
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What is the purpose of Prostaglandin F2-alpha and the Prostaglandin F receptor in the melatonin cell signaling pathway?
I've been doing a lot of research recently on the melatonin cell signaling pathway for an extra credit project at school. I've included an image in this post, which is a diagram of the MT1 pathway. It ...
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Do cells store information other than permanent (chromosome) information
The brain stores information in neurons (i.e. neural networks), and cells store information in DNA. But with DNA, this is permanent information. There is a lot of potential temporary information in ...
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Are resonances the reason receptors work?
From Visual phototransduction - Wikipedia:
When struck by a photon, 11-cis retinal undergoes photoisomerization to all-trans retinal which changes the conformation of the opsin GPCR leading to ...
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meaning of binding capacity and binding affinity
Actually, I am unfamiliar to biology, so when I read a thesis, the term "binding capacity" and "binding affinity" are really confusing.
Since my major is unrelated to biology, I don't know correct ...
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Is the Insulin Receptor Considered an Enzyme?
Can we consider insulin receptor an enzyme? In other words, does the insulin receptor have enzymatic characteristics?
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Protein/ligand affinity databases?
Is there any database that contain binding affinities reported in litterature for different proteins and ligands?
I have checked uniprot already and it does not seem to included any binding affinity ...
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Trypsin and Cell Surface Receptors
Can adding Trypsin to mammalian cells affect the expression of or hydrolyze cell surface receptors?
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What are the distinct neurochemical components of sexual pleasure?
Sexual activity is usually described as pleasurable.
What neurochemical systems does sex activate? Does the presence or absence of a partner make a difference -- say, in the activation of the ...
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How does receptor downregulation/upregulation work?
My understanding is that if a cell is flooded with a certain neurotransmitter, it may decrease the density of that neurotransmitter. What I don't understand is how.
Is it a direct physical result of ...
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Terminology regarding sensory receptors
I was recently asked the following question:
Compare the following pairs of receptors in the same
sensory system. Include in your discussion:
The distribution in the
sensory epithelium;...
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Could all mammalian receptors be described as allosteric?
Allosteric regulation in enzymes is where a molecule binds at a site other than the active site and thus changes the tertiary structure of the active site, hence altering the binding of substrate and ...
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