Rationalise the concept of multiple receptor states for G protein coupled receptors and how this might be used to develop novel and more selective drugs.
G protein coupled receptors (GPCR) are a huge transmembrane receptor protein family which are able to respond to a variety of extracellular stimulus such as photons, small molecules, peptides and proteins (hormones, neurotransmitters and paracrine agents). The contact of these receptors with its ligands will promote several transduction signals and finally a specific cellular response. In human, these receptors are involved in several neurological, cardiovascular, endocrine and reproductive functions. This ubiquity make GPCR the main target to develop drugs treatments (around 40% of modern drugs are targeted to GPCR).
Depending on the G protein coupled receptor and It ligands, drugs has been synthesized to mimic or block signals for these receptors, making a selective treatment for patients. But how this works? The receptors are able to bind to Its ligands on the extracellular side leading to the activation by the ligand (or drug). This will cause a conformational change leading to the intracellular loops to bind and activate the G protein. Once, the G-protein is activated, It will dissociate from the receptor and its subunits will activate a second messenger response activating or inhibiting other effector molecules (for example phospholipases or enzymes)
Rationalise the concept of multiple receptor states for G protein coupled receptors and how this might be used to develo...
Rationalise the concept of multiple receptor states for G protein coupled receptors and how this might be used to develop novel and more selective drugs.
Question 6 You and your G-protein coupled receptors o You have encountered G-protein coupled receptors in Intro Bio I lecture (or soon will), and will encounter them briefly again in Intro Bio II. You will spend 2 or 3 lectures on them in Cell Bio. They are integral (transmembrane) proteins embedded in the plasma membrane of every eukaryotic cell in your body. We will treat them as being 50 Angstroms in diameter. Considering the plasma membrane scaled up to the...
Diagram the activation of the 5-HT Serotonin Receptor (G-Protein Coupled Receptor) leading to transcriptional activation in a neuron. Include signaling pathways you have learned about in lecture or in your reading that involve G-Protein Coupled Receptors and lead to gene activation. Demonstrate how Lithium acts to disrupt one of these signaling pathways.
Diagram the activation of the 5-HT Serotonin Receptor (G-Protein Coupled Receptor) leading to transcriptional activation in a neuron. Include signaling pathways you have learned about in lecture or in your reading that involve G- Protein Coupled Receptors and lead to gene activation. Demonstrate how Lithium acts to disrupt one of these signaling pathways. (20 points) 5.
Some G-protein coupled receptors (GPCRs) are associated with a protein called RGS, which stimulates the GTPase activity of the receptor’s G-protein. What effect does RGS have on GPCR signaling? a. Signaling events are activated (upregulated) due to an increase in cAMP levels. b. Signaling events are downregulated due to disruption of the receptor-ligand interaction. c. Signaling events are activated as PKA as inhibition from the regulatory subunits is abolished. d. Signaling events are downregulated as the G-protein adopts its inactive...
4. What type of membrane protein is this G-protein Coupled Receptor (GPCR) integral or peripheral) and describe the features that contribute to its function in the cell? 5. How does the low GTPase activity in the mutated protein result in the constitutive activation of the G a protein and adenylate cyclase?
Ligand binding to a G-protein coupled receptor (GPCR) results in activation of a single G- protein and then the receptor deactivates. O True False When an activated receptor relays the signal along more than one pathways this is called convergence. O True OFalse Which of the following best describes digestive enzymes? O Hydrolases OLigases Kinases Transferases Decarboxylases Most digestive enzymes are released from cells in an inactive form. True False denatures Protein digestion in humans (and other mammals) begins in...
10. Describe how different G protein-coupled receptors can give rise to the synthesis of different 2nd messengers. EXTRA 5 points: Name three such G protein-induced 2nd messengers and name their subsequent target.
10. Describe how different G protein-coupled receptors can give rise to the synthesis of different 2nd messengers. EXTRA 5 points: Name three such G protein-induced 2nd messengers and name their subsequent target.
22. Steroids bind receptors that are a. Located in the cytoplasm b. G protein-coupled c. Integral membrane proteins d. Peripheral membrane proteins 23. Which of the following is the sequence of events in cortisol signaling? a. Gene expression, release of the inhibitor from the receptor, binding of ligand, exposure of DNA binding site, change in conformation of receptor b. Binding of ligand, exposure of DNA binding site, change in conformation of receptor, release of inhibitor from receptor, gene expression c....
How are g-protein linked receptors relative to psychotropic drugs