Podcast
Questions and Answers
What is the primary function of second messengers in signal transduction?
What is the primary function of second messengers in signal transduction?
- To generate energy for the cell
- To inhibit cell division
- To activate/inactivate target proteins (correct)
- To transport molecules across the membrane
Which G protein is associated with the activation of phospholipase C (PLC)?
Which G protein is associated with the activation of phospholipase C (PLC)?
- Gq (correct)
- Gi
- Gs
- G12/13
What is the role of Protein Kinase A (PKA) in cell signaling?
What is the role of Protein Kinase A (PKA) in cell signaling?
- To transport calcium ions
- To degrade glucose
- To phosphorylate target proteins (correct)
- To synthesize cAMP
What effect does glucagon have on liver cells according to the signal transduction pathway?
What effect does glucagon have on liver cells according to the signal transduction pathway?
What is the transcription factor that binds to the cAMP response element (CRE)?
What is the transcription factor that binds to the cAMP response element (CRE)?
Which of the following is a second messenger produced by the activation of phospholipase C?
Which of the following is a second messenger produced by the activation of phospholipase C?
Which G protein-coupled receptor is involved in excessive cell proliferation and malignancies?
Which G protein-coupled receptor is involved in excessive cell proliferation and malignancies?
How does cAMP function in the regulation of blood glucose levels?
How does cAMP function in the regulation of blood glucose levels?
What is the typical cytosolic concentration of Ca2+ that is maintained to optimize the 'signal:noise' ratio?
What is the typical cytosolic concentration of Ca2+ that is maintained to optimize the 'signal:noise' ratio?
What mechanism does Calcium Induced Calcium Release (CICR) utilize?
What mechanism does Calcium Induced Calcium Release (CICR) utilize?
How does the cortical reaction prevent polyspermy?
How does the cortical reaction prevent polyspermy?
Which receptor is activated by sperm binding to initiate calcium release during fertilization?
Which receptor is activated by sperm binding to initiate calcium release during fertilization?
What is the consequence of an increase in cytosolic Ca2+ concentration during fertilization?
What is the consequence of an increase in cytosolic Ca2+ concentration during fertilization?
What is the primary role of cAMP in liver cells in response to glucagon or epinephrine?
What is the primary role of cAMP in liver cells in response to glucagon or epinephrine?
Which enzyme is responsible for the cleavage of phosphatidylinositol bisphosphate (PIP2) into IP3 and DAG?
Which enzyme is responsible for the cleavage of phosphatidylinositol bisphosphate (PIP2) into IP3 and DAG?
What happens to cytosolic cGMP levels when light activates rhodopsin in rod cells?
What happens to cytosolic cGMP levels when light activates rhodopsin in rod cells?
Which G protein is activated by light in rod cells?
Which G protein is activated by light in rod cells?
What is the effect of RGS9 mutations on cGMP activity in patients with bradyopsia?
What is the effect of RGS9 mutations on cGMP activity in patients with bradyopsia?
Which of the following statements is true regarding G protein-coupled receptors (GPCRs)?
Which of the following statements is true regarding G protein-coupled receptors (GPCRs)?
In which part of the cell do IP3 and DAG act as second messengers?
In which part of the cell do IP3 and DAG act as second messengers?
What is the main effect of increased cAMP in cells that utilize Gs proteins?
What is the main effect of increased cAMP in cells that utilize Gs proteins?
Which second messenger is specifically associated with the action of phosphatidylinositol-derived pathways?
Which second messenger is specifically associated with the action of phosphatidylinositol-derived pathways?
What physiological process do G12/13 proteins primarily influence?
What physiological process do G12/13 proteins primarily influence?
What is the initial effect of alpha 2 adrenergic receptors on cAMP?
What is the initial effect of alpha 2 adrenergic receptors on cAMP?
Which second messengers are generated from the breakdown of PIP2?
Which second messengers are generated from the breakdown of PIP2?
What activates phospholipase C (PLCβ) in the signaling pathway?
What activates phospholipase C (PLCβ) in the signaling pathway?
What does DAG do upon activation in the cell membrane?
What does DAG do upon activation in the cell membrane?
What effect does IP3 have in the signaling pathway?
What effect does IP3 have in the signaling pathway?
Which of the following ligands does NOT activate phospholipase C (PLCβ)?
Which of the following ligands does NOT activate phospholipase C (PLCβ)?
What is the result of calcium release into the cytosol?
What is the result of calcium release into the cytosol?
Phosphatidylinositol bisphosphate (PIP2) is phosphorylated to produce which compound?
Phosphatidylinositol bisphosphate (PIP2) is phosphorylated to produce which compound?
Which of the following is NOT a receptor associated with G protein-coupled receptors as mentioned?
Which of the following is NOT a receptor associated with G protein-coupled receptors as mentioned?
What is one of the primary functions of protein kinase C (PKC)?
What is one of the primary functions of protein kinase C (PKC)?
Which type of PKC isozyme requires both DAG and Ca2+ for activation?
Which type of PKC isozyme requires both DAG and Ca2+ for activation?
What is the primary role of Ca2+ as an intracellular messenger?
What is the primary role of Ca2+ as an intracellular messenger?
Which PKC isozymes are classified as novel or nonclassic?
Which PKC isozymes are classified as novel or nonclassic?
What mechanism is NOT involved in maintaining low calcium levels in the cytosol?
What mechanism is NOT involved in maintaining low calcium levels in the cytosol?
Which of the following is a consequence of elevated intracellular Ca2+ levels?
Which of the following is a consequence of elevated intracellular Ca2+ levels?
What type of diseases are associated with abnormal PKC signaling?
What type of diseases are associated with abnormal PKC signaling?
Which of the following cellular processes does NOT involve Ca2+ signaling?
Which of the following cellular processes does NOT involve Ca2+ signaling?
What is the primary factor that contributes to the 'signal:noise' ratio in Ca2+ signaling?
What is the primary factor that contributes to the 'signal:noise' ratio in Ca2+ signaling?
Which PKC isozyme class does not require either DAG or Ca2+ for activation?
Which PKC isozyme class does not require either DAG or Ca2+ for activation?
In the context of Ca2+ signaling, what specifically triggers muscle contraction?
In the context of Ca2+ signaling, what specifically triggers muscle contraction?
Which G protein is associated with increasing intracellular cAMP levels?
Which G protein is associated with increasing intracellular cAMP levels?
What is the primary action of protein kinase C (PKC) in cell signaling?
What is the primary action of protein kinase C (PKC) in cell signaling?
Which second messenger is formed as a result of phosphatidylinositol bisphosphate (PIP2) cleavage?
Which second messenger is formed as a result of phosphatidylinositol bisphosphate (PIP2) cleavage?
What is the role of calcium in the signaling pathways discussed?
What is the role of calcium in the signaling pathways discussed?
Which cellular process is NOT primarily influenced by G protein-coupled receptor signaling?
Which cellular process is NOT primarily influenced by G protein-coupled receptor signaling?
How does the activation of phospholipase C affect intracellular signaling?
How does the activation of phospholipase C affect intracellular signaling?
Which outcome is primarily associated with elevated intracellular cAMP levels?
Which outcome is primarily associated with elevated intracellular cAMP levels?
Which transcription factor is activated by phosphorylated cAMP response element binding protein (CREB)?
Which transcription factor is activated by phosphorylated cAMP response element binding protein (CREB)?
What is the primary reason for maintaining a low cytosolic concentration of Ca2+?
What is the primary reason for maintaining a low cytosolic concentration of Ca2+?
How does Calcium Induced Calcium Release (CICR) primarily function?
How does Calcium Induced Calcium Release (CICR) primarily function?
What is the role of IP3 receptors in calcium signaling during fertilization?
What is the role of IP3 receptors in calcium signaling during fertilization?
What prevents more than one sperm from fertilizing an egg?
What prevents more than one sperm from fertilizing an egg?
What critical process is facilitated by ryanodine receptors (RyRs) in muscle cells?
What critical process is facilitated by ryanodine receptors (RyRs) in muscle cells?
What triggers muscle contraction in relation to intracellular calcium levels?
What triggers muscle contraction in relation to intracellular calcium levels?
What is a physiological consequence of elevated intracellular Ca2+ levels?
What is a physiological consequence of elevated intracellular Ca2+ levels?
Which of the following diseases is associated with abnormal PKC signaling?
Which of the following diseases is associated with abnormal PKC signaling?
What mechanism maintains low calcium levels in the cytosol?
What mechanism maintains low calcium levels in the cytosol?
Which PKC isozymes require DAG but not Ca2+ for activation?
Which PKC isozymes require DAG but not Ca2+ for activation?
What is the most widely used intracellular messenger involved in signaling processes?
What is the most widely used intracellular messenger involved in signaling processes?
What role does histamine release play in cell signaling?
What role does histamine release play in cell signaling?
How does the cytosolic concentration of Ca2+ influence the 'signal:noise' ratio?
How does the cytosolic concentration of Ca2+ influence the 'signal:noise' ratio?
What type of signaling does Protein Kinase C (PKC) mediate?
What type of signaling does Protein Kinase C (PKC) mediate?
What effect do alpha 2 adrenergic receptors have on cAMP levels?
What effect do alpha 2 adrenergic receptors have on cAMP levels?
Which intracellular component is produced when phospholipase C (PLCβ) cleaves PIP2?
Which intracellular component is produced when phospholipase C (PLCβ) cleaves PIP2?
What role does diacylglycerol (DAG) play after it is generated in the signaling pathway?
What role does diacylglycerol (DAG) play after it is generated in the signaling pathway?
Which receptor is NOT mentioned as relevant in the context of G Protein-Coupled Receptors?
Which receptor is NOT mentioned as relevant in the context of G Protein-Coupled Receptors?
What is the initial event that occurs after a ligand binds to a G protein-coupled receptor (GPCR)?
What is the initial event that occurs after a ligand binds to a G protein-coupled receptor (GPCR)?
What happens to calcium ions after IP3 diffuses into the cytosol?
What happens to calcium ions after IP3 diffuses into the cytosol?
Which of the following processes is influenced by protein kinase C (PKC) upon activation?
Which of the following processes is influenced by protein kinase C (PKC) upon activation?
What triggers the activation of phospholipase C (PLCβ) in the signaling pathway?
What triggers the activation of phospholipase C (PLCβ) in the signaling pathway?
What is a common consequence of calcium being released into the cytosol?
What is a common consequence of calcium being released into the cytosol?
In the generation of second messengers, what is the first step involving PhosphoInositides (PIP2)?
In the generation of second messengers, what is the first step involving PhosphoInositides (PIP2)?
Which enzyme is responsible for the decreasing levels of cGMP in response to light activation in rod cells?
Which enzyme is responsible for the decreasing levels of cGMP in response to light activation in rod cells?
What is the effect of decreasing cGMP levels in rod cells when light is present?
What is the effect of decreasing cGMP levels in rod cells when light is present?
Which G protein is primarily associated with the light-activated signaling pathway in rods?
Which G protein is primarily associated with the light-activated signaling pathway in rods?
What role does RGS9 play in the signaling process of rod cells?
What role does RGS9 play in the signaling process of rod cells?
What is the effect of G12/13 proteins on cellular processes?
What is the effect of G12/13 proteins on cellular processes?
What is the by-product of phosphatidylinositol bisphosphate (PIP2) cleavage by phospholipase C?
What is the by-product of phosphatidylinositol bisphosphate (PIP2) cleavage by phospholipase C?
How does cAMP production differ between Gs and Gi G proteins?
How does cAMP production differ between Gs and Gi G proteins?
What function does diacylglycerol (DAG) serve in the cell after activation?
What function does diacylglycerol (DAG) serve in the cell after activation?
What defines the role of phospholipase enzymes in cell signaling?
What defines the role of phospholipase enzymes in cell signaling?
Which of the following is true regarding inositol trisphosphate (IP3) function?
Which of the following is true regarding inositol trisphosphate (IP3) function?
What primarily prevents more than one sperm from fertilizing an egg during the cortical reaction?
What primarily prevents more than one sperm from fertilizing an egg during the cortical reaction?
Which component is essential for facilitating rapid calcium release during muscle contraction?
Which component is essential for facilitating rapid calcium release during muscle contraction?
What is the role of IP3 receptors in the context of calcium signaling?
What is the role of IP3 receptors in the context of calcium signaling?
How is the cytosolic concentration of Ca2+ typically maintained at a low level?
How is the cytosolic concentration of Ca2+ typically maintained at a low level?
What characteristic of calcium signaling optimizes the 'signal:noise' ratio?
What characteristic of calcium signaling optimizes the 'signal:noise' ratio?
What is the consequence of activating the Gq protein in signal transduction?
What is the consequence of activating the Gq protein in signal transduction?
Which role does p-CREB play in the context of cAMP signaling?
Which role does p-CREB play in the context of cAMP signaling?
How does the activation of protein kinase C (PKC) influence cellular functions?
How does the activation of protein kinase C (PKC) influence cellular functions?
The signaling pathway initiated by glucagon and epinephrine primarily affects which organ's cells?
The signaling pathway initiated by glucagon and epinephrine primarily affects which organ's cells?
What mechanisms primarily maintain low calcium levels in the cytosol under resting conditions?
What mechanisms primarily maintain low calcium levels in the cytosol under resting conditions?
What is the consequence of Gαq activation in the signaling pathway?
What is the consequence of Gαq activation in the signaling pathway?
Which of the following statements best describes the role of DAG in signal transduction?
Which of the following statements best describes the role of DAG in signal transduction?
Which of the following ligands does NOT promote the activation of phospholipase C?
Which of the following ligands does NOT promote the activation of phospholipase C?
What is a key distinguishing feature of G12/13 protein signaling compared to other G proteins?
What is a key distinguishing feature of G12/13 protein signaling compared to other G proteins?
What is one consequence of increased intracellular calcium levels in a muscle cell?
What is one consequence of increased intracellular calcium levels in a muscle cell?
Which statement about IP3 and DAG is true?
Which statement about IP3 and DAG is true?
What role does DAG play after its formation from PIP2?
What role does DAG play after its formation from PIP2?
Which process is triggered by the binding of IP3 to smooth endoplasmic reticulum receptors?
Which process is triggered by the binding of IP3 to smooth endoplasmic reticulum receptors?
Which G protein is primarily involved in the reduction of cAMP levels?
Which G protein is primarily involved in the reduction of cAMP levels?
What is the first step in the generation of second messengers from phosphatidylinositol bisphosphate (PIP2)?
What is the first step in the generation of second messengers from phosphatidylinositol bisphosphate (PIP2)?
What is NOT a direct role served by calcium ions released into the cytosol?
What is NOT a direct role served by calcium ions released into the cytosol?
Which PKC isozymes require DAG for activation but do not require Ca2+?
Which PKC isozymes require DAG for activation but do not require Ca2+?
What is one of the primary functions of elevated intracellular Ca2+ levels?
What is one of the primary functions of elevated intracellular Ca2+ levels?
Muscarinic receptors categorized as type 1, 3, and 5 are associated with which function?
Muscarinic receptors categorized as type 1, 3, and 5 are associated with which function?
Which mechanism does NOT contribute to maintaining low cytosolic Ca2+ levels?
Which mechanism does NOT contribute to maintaining low cytosolic Ca2+ levels?
What is the final product after PIP2 is cleaved by phospholipase C?
What is the final product after PIP2 is cleaved by phospholipase C?
What type of PKC isoforms are classified as atypical?
What type of PKC isoforms are classified as atypical?
In relation to G Protein-Coupled Receptors (GPCRs), what does IP3 primarily facilitate?
In relation to G Protein-Coupled Receptors (GPCRs), what does IP3 primarily facilitate?
Which of the following diseases is NOT linked to abnormal PKC signaling?
Which of the following diseases is NOT linked to abnormal PKC signaling?
What role does Ca2+ play in T cell activation?
What role does Ca2+ play in T cell activation?
Which of the following is a characteristic of conventional PKC isozymes?
Which of the following is a characteristic of conventional PKC isozymes?
What cellular function does NOT typically involve Ca2+ signaling?
What cellular function does NOT typically involve Ca2+ signaling?
Which is an effect of increased intracellular Ca2+ concentration?
Which is an effect of increased intracellular Ca2+ concentration?
What effect does light have on cGMP levels in rod cells?
What effect does light have on cGMP levels in rod cells?
Which process is primarily activated by the cleavage of PIP2?
Which process is primarily activated by the cleavage of PIP2?
Which G protein is involved in the signaling pathway that results in a decrease of cAMP levels?
Which G protein is involved in the signaling pathway that results in a decrease of cAMP levels?
What is the primary role of RGS9 in the context of light signaling in vision?
What is the primary role of RGS9 in the context of light signaling in vision?
What happens to Na+ and Ca2+ channels in rod cells when cGMP levels decrease due to light exposure?
What happens to Na+ and Ca2+ channels in rod cells when cGMP levels decrease due to light exposure?
Which of the following is a consequence of decreased cGMP levels in rod cells?
Which of the following is a consequence of decreased cGMP levels in rod cells?
How does phospholipase C contribute to intracellular signaling?
How does phospholipase C contribute to intracellular signaling?
What role does diacylglycerol (DAG) play in cell signaling?
What role does diacylglycerol (DAG) play in cell signaling?
Which factor primarily contributes to bradyopsia in patients with mutations in the RGS9 gene?
Which factor primarily contributes to bradyopsia in patients with mutations in the RGS9 gene?
What is the immediate effect of activating Gq-coupled receptors?
What is the immediate effect of activating Gq-coupled receptors?
Flashcards
Signal Transduction
Signal Transduction
Process of transmitting signals within a cell, often involving a cascade of reactions.
Second Messenger
Second Messenger
Small molecules that carry signals from cell surface receptors to target proteins inside the cell.
IP3
IP3
Inositol Triphosphate; a second messenger.
DAG
DAG
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PKC
PKC
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G protein-coupled receptor
G protein-coupled receptor
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cAMP
cAMP
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CREB
CREB
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Rhodopsin
Rhodopsin
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cGMP phosphodiesterase
cGMP phosphodiesterase
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Bradyopsia
Bradyopsia
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Phospholipase C (PLC)
Phospholipase C (PLC)
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Ca2+ Concentration in Cells
Ca2+ Concentration in Cells
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Calcium-Induced Calcium Release (CICR)
Calcium-Induced Calcium Release (CICR)
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IP3 Receptors (IP3Rs)
IP3 Receptors (IP3Rs)
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Ryanodine Receptors (RyRs)
Ryanodine Receptors (RyRs)
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Cortical Reaction
Cortical Reaction
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PKC Signaling
PKC Signaling
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Conventional PKC
Conventional PKC
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Novel PKC
Novel PKC
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Atypical PKC
Atypical PKC
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Ca²⁺ Signaling
Ca²⁺ Signaling
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Intracellular Ca²⁺
Intracellular Ca²⁺
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Calcium Transport
Calcium Transport
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G Protein-Coupled Receptors (GPCRs)
G Protein-Coupled Receptors (GPCRs)
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Second Messengers (IP3 and DAG)
Second Messengers (IP3 and DAG)
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Phosphoinositides (PIP2)
Phosphoinositides (PIP2)
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Protein Kinase C (PKC)
Protein Kinase C (PKC)
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Calcium Ions (Ca2+)
Calcium Ions (Ca2+)
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Gαq Protein
Gαq Protein
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Ligand
Ligand
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Calcium's role in signaling
Calcium's role in signaling
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What is rhodopsin?
What is rhodopsin?
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What is the role of cGMP in vision?
What is the role of cGMP in vision?
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What is transducin?
What is transducin?
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What is cGMP phosphodiesterase?
What is cGMP phosphodiesterase?
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What is the effect of bradyopsia on vision?
What is the effect of bradyopsia on vision?
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What is the role of phospholipase C (PLC) in cell signaling?
What is the role of phospholipase C (PLC) in cell signaling?
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What is PIP2?
What is PIP2?
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What is IP3?
What is IP3?
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What is DAG?
What is DAG?
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What triggers the release of histamine?
What triggers the release of histamine?
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What is the role of G Protein-Coupled Receptors (GPCRs)?
What is the role of G Protein-Coupled Receptors (GPCRs)?
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How is PKC signaling abnormal in diseases?
How is PKC signaling abnormal in diseases?
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What is the role of IP3 in Ca2+ signaling?
What is the role of IP3 in Ca2+ signaling?
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What is the importance of Ca2+?
What is the importance of Ca2+?
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Why is the cytosolic Ca2+ concentration low?
Why is the cytosolic Ca2+ concentration low?
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How is low calcium level maintained?
How is low calcium level maintained?
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What are Conventional PKCs?
What are Conventional PKCs?
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What are Novel PKCs?
What are Novel PKCs?
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What is the role of Gαq in the IP3/DAG pathway?
What is the role of Gαq in the IP3/DAG pathway?
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What does DAG do in cell signaling?
What does DAG do in cell signaling?
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What is the key action of PKC in the cell?
What is the key action of PKC in the cell?
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What is the effect of calcium release on the cell?
What is the effect of calcium release on the cell?
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How does the IP3/DAG pathway get started?
How does the IP3/DAG pathway get started?
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Why is PIP2 important in the IP3/DAG pathway?
Why is PIP2 important in the IP3/DAG pathway?
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What are some examples of ligands that activate the IP3/DAG pathway?
What are some examples of ligands that activate the IP3/DAG pathway?
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How does the IP3/DAG pathway contribute to smooth muscle contraction?
How does the IP3/DAG pathway contribute to smooth muscle contraction?
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What is the significance of the IP3/DAG pathway in cell signaling?
What is the significance of the IP3/DAG pathway in cell signaling?
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How is calcium released?
How is calcium released?
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What does PKC do?
What does PKC do?
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The IP3/DAG pathway
The IP3/DAG pathway
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Gαq
Gαq
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Transducin
Transducin
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Abnormal PKC Signalling
Abnormal PKC Signalling
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Ca2+ Signalling
Ca2+ Signalling
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Low Cytosolic Ca2+ Concentration
Low Cytosolic Ca2+ Concentration
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IP3/DAG Pathway
IP3/DAG Pathway
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What triggers the IP3/DAG pathway?
What triggers the IP3/DAG pathway?
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What are the key roles of IP3 and DAG?
What are the key roles of IP3 and DAG?
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How does the IP3/DAG pathway influence smooth muscle contraction?
How does the IP3/DAG pathway influence smooth muscle contraction?
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Why is cytosolic Ca2+ kept low?
Why is cytosolic Ca2+ kept low?
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How does IP3 trigger Ca2+ release?
How does IP3 trigger Ca2+ release?
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What's the role of ryanodine receptors?
What's the role of ryanodine receptors?
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How does fertilization prevent polyspermy?
How does fertilization prevent polyspermy?
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Study Notes
HSS2305: Molecular Mechanisms of Disease
- Lecture 16 covered Signal Transduction, specifically IP3, DAG, and PKC.
- Today's outline included announcements and sections on Signal Transduction.
Cell Signaling Overview
- Cell signaling involves three key steps:
- Reception: Signaling molecule binds to receptor on plasma membrane
- Transduction: Relay molecules within signaling pathway
- Response: Activation of cellular response (e.g., gene expression, metabolic changes)
Signal Transduction
- Two primary routes:
- Generation of intracellular second messengers via effector enzymes: Second messengers activate/inactivate target proteins
- Recruit signaling proteins to their intracellular domains to initiate a protein-activated cascade: Proteins initiate further cascade of protein activation.
G Protein-Coupled Receptors
- Receptors in cell membrane bind signaling molecules.
- The activated receptor triggers a response by altering an enzyme.
- G protein system converts extracellular signal to intracellular signaling.
G Protein-Coupled Receptors (Effectors)
- G proteins are involved in signaling pathways that influence many cellular processes.
- Different G proteins lead to diverse second messengers.
- Two main categories of second messengers are cAMP and IP3/DAG.
G Protein-Coupled Receptors (2nd messengers - cAMP)
- cAMP triggers a biochemical cascade in a cell.
- The pathway affects many aspects of cell function.
- CREB: cAMP response element-binding protein acts as a transcription factor.
- Increased cAMP transcription of genes influences many processes like gluconeogenesis.
G Protein-Coupled Receptors (2nd messengers - IP3 & DAG)
- DAG activates another enzyme, protein kinase C (PKC).
- PKC regulates cellular processes like growth, differentiation, metabolism, and death.
- IP3 activates calcium channels, leading to calcium influx into the cytosol.
G Protein-Coupled Receptors (Ca2+ Signaling)
- Cystolic Ca2+ concentration is kept low through active transport and sequestration.
- Increases in cytosolic Ca2+ trigger various intracellular responses.
- Ca2+ signaling is involved in muscle contraction, neurotransmitter release, and other cellular processes.
G Protein-Coupled Receptors (Calcium Signaling and Fertilization)
- Sperm binding triggers a calcium influx.
- This induces a cortical reaction in the egg, preventing polyspermy (multiple fertilization).
Next Lecture
- The next lecture will focus on RTKs and MAPK signaling pathways.
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Description
This quiz focuses on Lecture 16 of the HSS2305 course, covering Signal Transduction mechanisms, including IP3, DAG, and PKC. Explore the fundamental steps of cell signaling, the role of second messengers, and the function of G Protein-Coupled Receptors in cellular responses. Test your understanding of these critical molecular mechanisms of disease.
