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The activation of receptor tyrosine kinases is characterized by?
Wiki User
∙ 13y ago
dimerization and phosphorylation.
Wiki User
∙ 13y ago
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The activation of receptor tyrosine kinases is characterized by what?
Dimerization and phosphorylation
What is the function of receptor proteins?
Receptor proteins are designed so special molecules can bind to them, and send messages to the cell that trigger some sort of reaction within the cell.They are embedded in either the plasma membrane or cytoplasm of a cell, to which a mobile signaling (or "signal") molecule may attach.Sources: http://en.wikipedia.org/wiki/Receptor_proteins
What is tyrosine kinase receptor dimerization. Receptor polymorphism and dimerization in drug design?
Tyrosine kinases are present in the membrane as separate entities that are able to dimerize with one another when bound to a ligand...for this reason most TK ligands are multivalent (thus can bind multiple TK's and cluster them with the ability to dimerize for activation...a dimer is simply two TK's together. I suppose I would need a better understanding of what you mean by the latter part of the question. Receptors can be influenced by polymorphisms (different "formula" variations that are expressed in populations which influence binding...Ex replacing a neutral amino acid with a positive affects binding correct?....As far as dimerization as it relates to drug design I must first confess that I'm not a pharmacologist... however my guess would be that they would want to make their products multivalent so that they bind multiple TK's so that they are able to dimerize...(this is merely a guess)
What would inhibit a receptor?
You can inhibit a receptor by either of 2 ways, one being specific one being not so specific. First of all if you have kinases they have a DNA binding domain as well as a catalytic region and ATP region. First you have to identify what you cell has for receptors this may be difficult because .01% of the cells mass are these receptors. Most identified by recomiant DNA, so you can find them by there DNA binding conserved sequence. Not all of them also have to be on the surface some maybe in the cytosol of the protien. So you can make a specific inhibitors for there receptor domain because these are specific. For cancer you want a dirty inhibitor to inhibit a lot of kinases.
Explain how an original signal molecule can produce a cellular response when it may not even enter the target cell?
There are a few ways that this happens. One way is through synaptic signalling. This signalling occurs in the nervous system. An electric signal along a nerve cell triggers the secretion of a chemical signal in the form of neurotransmitter molecules. These diffuse across the synapse, these neurotransmitters stimulate the target cell. Another type of signalling is paracrine signalling. The secreting cell acts on nearby target cells by discharging molecules of a local regulator like a growth factor into the extracellular fluid. Both animals and plants use hormones for long distance signalling. With this cell communication, specialized endocrine cells secrete hormones into body fluids, often the blood. Hormomes may reach virtually all body cells. What happens when a cell encounters a signal? The signal must be recognized by a specific receptor molecule, and the information it carries must be changed into another form, transduced before the cell can respond. So generally the cells generally communicate via chemical messengers targeted for cells. Addition of general pathways:A signal molecule such as a peptide hormone produce a cellular response by binding to receptor proteins on the cell membrane. These molecules may be involved in endocrine (systemic-global), paracrine (tissue-local), autocrine (self-local), or nervous (restricted to synaptic junctions) signaling. The receptor proteins for these signal molecules have very high specificity for a particular kind of molecules and respond by either directly opening a gated channel, creating a secondary messenger molecule, or directly phosphorylating downstream molecules to initiate a signal cascade that result in a subtle or gross alteration in the cell's state of operation through the activation/deactivation of enzymes and the activation/deactivation of transcription factors controlling gene expression. Recurring archetypes of these receptors include ligand gated channels (example: acetylcholine receptors in neuromuscular junctions. Binding of acetylcholine causes the opening of ion channels that propagate the action potential), G-protein coupled receptors (example: adrenergic receptors. Binding of adrenaline initiates G-protein activation and results in the production of secondary messenger molecules cAMP, which activate downstream target molecules that effect changes), Receptor tyrosine kinases (example: insulin receptor. Binding of insulin leads to the recruitment of downstream proteins and their activation through phosphorylation on tyrosine residues).
The activation of receptor tyrosine kinases is characterized by what?
Dimerization and phosphorylation
The receptor for a group of signaling molecules known as growth factors are often?
receptor tyrosine kinases
What is the difference of g-protein receptor system and tyrosine kinase receptor?
Receptor tyrosine kinases do not require the use of second messengers while G protein-coupled receptors need.
What has the author J Schlessinger written?
J. Schlessinger has written: 'Cellular signaling by receptor tyrosine kinases'
What are membrane receptors that attach phosphates to specific animo acids in proteins?
called receptor tyrosine-kinases
What has the author Joanne Chan written?
Joanne Chan has written: 'Characterizaton of receptor protein-tyrosine kinases, EEK and IRR'
What is One of the major categories of receptors in the plasma membrane that reacts by forming dimmers adding phosphate groups then activating relay proteins?
Receptor tyrosine kinases
What has the author Tomas Mustelin written?
Tomas Mustelin has written: 'Src family tyrosine kinases in leukocytes' -- subject(s): Genes, src, Genetics, Leucocytes, Leukocytes, Metabolism, Physiology, Protein-tyrosine kinase
What is the function of receptor proteins?
Receptor proteins are designed so special molecules can bind to them, and send messages to the cell that trigger some sort of reaction within the cell.They are embedded in either the plasma membrane or cytoplasm of a cell, to which a mobile signaling (or "signal") molecule may attach.Sources: http://en.wikipedia.org/wiki/Receptor_proteins
What is tyrosine kinase receptor dimerization. Receptor polymorphism and dimerization in drug design?
Tyrosine kinases are present in the membrane as separate entities that are able to dimerize with one another when bound to a ligand...for this reason most TK ligands are multivalent (thus can bind multiple TK's and cluster them with the ability to dimerize for activation...a dimer is simply two TK's together. I suppose I would need a better understanding of what you mean by the latter part of the question. Receptors can be influenced by polymorphisms (different "formula" variations that are expressed in populations which influence binding...Ex replacing a neutral amino acid with a positive affects binding correct?....As far as dimerization as it relates to drug design I must first confess that I'm not a pharmacologist... however my guess would be that they would want to make their products multivalent so that they bind multiple TK's so that they are able to dimerize...(this is merely a guess)
How host cell behavior alters by pathogen?
A cell transmutes a stimulus on the outside of the plasma membrane into changes in the cell's physiological program by means of intracellular signaling pathways. These are usually triggered by the ligation of an external ligand, such as a cytokine or a Leishmania surface molecule, to a receptor on the cell surface. This ligation causes activation of the receptor, commonly by phosphorylation and/or conformational changes, resulting in activation of second messengers within the cytosol. These second messengers are often protein kinases, which then phosphorylate other kinases to continue a cascade that ultimately results in the activation of effector molecules, such as transcription factors or actin filaments, and causing a change in the cell's behavior. It should be emphasized that the activity of an intracellular pathway is normally determined by a balance of both positive and negative regulation. Activation of a given kinase cascade will often result in the activation of its opposing phosphatases, in a classic example of negative feedback. Many prokaryotic and eukaryotic pathogens, including Leishmania, have evolved various strategies to exploit host cell signaling regulatory mechanisms by distorting this balance between positive and negative influences.
Compare two ways that the binding of a signal molecule to a receptor protein causes a change in activity the receiving cell?
1. Insulin binding to insulin receptor tyrosine kinase on hepatocyte: increased glucose uptake, increased glycogen and fatty acid production and decreased catabolism in general (decreased gluconeogenesis, lipolysis, and proteolysis). Insulin binding causes receptor dimerization and self-phosphorylation. Phosphorylated receptor recruits scaffold proteins and downstream target proteins and phosphorylate them. Phosphorylated target proteins serve as kinases and activate or deactivate other proteins by phosphorylation, effecting appropriate effects. 2. Erythropoietin binding to EPO cytokine receptor on Common Myeloid Progenitor cell: eventual differentiation into erythrocyte. Cytokine receptor induces the Jak/STAT pathway resulting in altered gene expression by transcription factors, drastically changing the function and morphology of the cell.
