Biosignaling and Carbohydrate Metabolism Flashcards
Name the 6 requirements for effective signal transduction.
- Specificity
- Amplification
- Modularity
- Integration
- Feedback
- Fidelity
Name the 4 components of signal transduction
- Signal
- Receptor
- Transduction pathways
- Targets
What are thee 3 different types of signals?
- Soluble
- Linked
- Physical
What are examples of Soluble signals?
- Proteins & Amino Acids
- Lipids & Fatty Acids
- Ceramide
- Testosterone
- Carbohydrates
What is an example of a linked signal
Integrin
What are some examples of physical receptors?
- Mechanical
- Light
- Opsin
- Temperature
- TRP channels
Name the 7 Receptor families
- G-Protein Coupled
- Receptor Tyrosine Kinase
- Receptor Guanylyl Cyclades
- Ligand Gated Ion channels
- Adhesion
- Nuclear
- Cytokine
Describe G protein coupled Receptors
External ligand binding to receptor activates an intracellular GTP-binding protein (G), which regulates an enzyme that generates an intra cellular second messenger.
Describe receptor tyrosine kinase
Ligand binding activates tyrosine kinase activity by autophosphorylation
Describe Receptor guanylyl cyclase
ligand binding to extra cellular domain stimulates formation of 2nd messenger cyclic GMP
Describe Gated ion channels
Opens or closes in response to concentration of signal ligand or membrane potential
Describe Adhesion receptor (integrin)
Binds molecules in extracellular matrix, changes conformation, thus altering its interaction with cytoskeleton
What are the cytokine receptor families?
- Interleukin Type 1
- Interleukin type 2
- TNFR (tumor necrosis factor receptor)
- Ig family
What cytokine receptor families activate JAK/STAT pathway?
- Interleukin type 1
2. Interleukin type 2
What cytokine receptor families activate PI3K/AKT pathway?
- Interleukin type 1
2. Interleukin type 2
What cytokine receptor families activate MAPK pathway?
- Interleukin type 1
- Interleukin type 2
- TNFR
- Ig family
What cytokine receptor families activate NFkB pathway ?
- TNFR
2. Ig Family
What 4 pathways are activate via cytokine receptor families?
- JAK/STAT
- PI3K/AKT
- MAPK
- NFkB
What are the 4 major roles that the plasma membrane plays in signaling?
- Receptor localization
- Ligand exposure
- Signaling complex formation
- Endocytosis
What are two examples of signal complexes made by plasma membranes?
- Protein Scaffolds
2. Signaling endosomes
name the 2 types of lipid rafts involved in signaling
- Planar
2. Caveolar
What roles can lipid rafts play in signaling?
- Signal promotion by organizing receptors and effectors to promote signaling
- Signal inhibition by separating signaling components
What proteins are critical for the endocytic pathway?
Rab GTPase proteins
T/F pH decreases along endocytic pathway
True
What are 3 ways the endocytic pathway regulates signaling?
- Downregulation
- Maintenance
- Signal Generation
What is the pathway of signal transduction?
- 1st messenger
- Receptor
- Signal transducer
- Primary effector
- 2nd messenger
- 2ndary effector
- Signaling cascade
What are three examples in which chemical reactions transfer information ?
- Complex formation or dissociation
- Structural change
- Post-translational modification
Name several prevalent post translational modifications
- Phosphorylation
- Ubiquitination
- Glycosylation
- Oxidation
- Methylation
- Acetylation
- SUMOylation
Name some common signaling cascades (4 of them)
- Mitogen-activated Protein Kinase (MAPK)
- Janus Kinase - Signal Tranducer and Activator of Transcription (JAK/STAT)
- Phosphatidylinositol 3-Kinase (PI3K)
- Phospholipase C (PLC)
PLC splits PIP2 into 2 things. What are they?
- IP3
2. DAG
Name some common targets of signaling pathways and what is affected by the signal
- Nucleus: Transcription, cell division
- Actin/Tubulin/Filaments: Cell structure and motility
- Enzymes: Initiate metabolic pathways
- Receptors: Alter signal transduction
- Transporters: change intracellular environment
- Ion channels: change membrane potential
What are two of the most relevant signaling pathways and what do they affect?
- Epinephrine Signaling: affects vascular tone
2. Insulin signaling: Regulates cellular division and metabolic processes
What signaling cascades are used by Epinephrine signaling?
- G-protein
2. PLC
What signaling pathways are used by Insulin signaling?
- RTK
- MAPK
- PI3K
T/F Epinephrine is coadministered with local anesthetic
True
What are some functions of insulin signaling pathway?
-Transports glucose into cells, alters blood sugar, enables aerobic respiration
What are the key cell types that regulate Metabolic pathways?
- Pancreas: Islet cells
- Liver: Hepatocyte
- Muscle: skeletal, smooth, and cardiac
- Adipose Tissue: Adipocyte
What is the metabolic function of hepatocytes in the liver?
Maintain metabolic homeostasis by normalizing blood glucose, storing glycogen, and synthesizing and degrading glycogen, glucose, fatty acids, nucleic acids, proteins and ketones
Name the key regulator molecules of metabolism?
- Insulin
- Glucagon
- Epinephrine
- Glucose
- ATP/AMP
What are the 4 fates of glucose?
- Source of ATP
- Energy Storage
- Molecule Precursor
- Structural Backbone
T/F Glucose 6-Phosphatase is only found in the ER of the liver
True
What causes Glycogen synthase to be activated again?
- Insulin
- Glucose 6-phosphate
- Glucose
What prevents Glycogen synthase from becoming reactivated?
- Glycogen Synthase Kinase 3 activity
2. Glucagon and Epinephrine
What causes glycogen phosphorylase to go from inactive to active and what is the enzyme that helps?
- glucagon
- Epinephrine (high Ca2+ and AMP)
Enzyme:
Phosphorylase Kinase
What is the enzyme that deactivates Glycogen Phosphorylase and where else does this enzyme function?
Phosphorylase a phosphatase (PP1)
** it also dephosphorylates glycogen synthase
What does insulin activate in response to high blood sugar?
- GLUTs
- Hexokinase
- Glycogen synthase
What serves to activate and inhibit PFK-1?
ACTIVATE:
- ADP
- AMP
INHIBIT:
- ATP
- Citrate
What serves to inhibit FBPase-1?
AMP
Presence of Acetyl CoA will activate ____________ while deactivating ___________
- Pyruvate Carboxylase
2. Pyruvate Dehydrogenase complex
