Warm-up

Cell Communication
CHAPTER 11
unicate?
igeria com
municate?
Cell Signaling
Anima
 Secreting local regulators (growth factors, neurotransmitters) Long distance (hormones) 3 Stages of Cell Signaling:
1. Reception: Detection of a signal molecule (ligand) coming from outside the cell2. Transduction: Convert signal to a form that can bring about a cellular response 3 Stages of Cell Signaling:
1.
4. Transduction: Convert signal to a form that can bring about a cellular response n : Cellular response to the signal molecule
Transduction
Reception
Response
Transduction
1. Reception
ding between signal molecule (ligand) + receptor is highly specific.
1. Reception
 Binding between signal molecule (ligand) + receptor is highly specific.
 Ligand binds to receptor protein  protein changes SHAPE  initiates transduction  Eg. testosterone or nitric oxide (NO) P Liga
las nd binds
ma Memb to re
ors in  protein changes SHAPE  initiates transduction
G-Protein-Coupled Receptor
Plasma Membrane Receptors
G-Protein-Coupled Receptor
G-Protein-Coupled Receptor
Receptor Tyrosine Kinase
G-Protein-Coupled Receptor
Ligand-Gated Ion Channel
Receptor Tyrosine Kinase
Plasma Membrane Receptors
Ligand-Gated Ion Channel
2. Transduction
ractions relay signals from receptors  target molecules  Protein kinase: enzyme that phosphorylates and activates proteins at next level 2. Transduction
 Phosphorylation cascade: enhance and amplify signal  Cascades of molecular interactions relay signals from receptors  target molecules  Protein kinase: enzyme that phosphorylates and activates proteins at next level  Phosphorylation cascade: enhance and amplify signal Second Messengers
 small, nonprotein molecules/ions that can relay signal inside cell  Eg. cyclic AMP (cAMP), calcium ions (Ca2+), inositol triphosphate (IP Second Messengers
poonprot
nse ein molecules/ions that can relay signal inside cell
 Regulate activity of proteins in cytoplasm 3. Response
An egulate
Examp prot
nicarnin
n on/off genes in nucleus (gene expression)
An Example of Cell Communication
ht
 Signal transduction pathways can be blocked or defective  Drugs (anesthetics, antihistamines, blood pressure meds) lera (anesthetics, antihistamines, blood pressure meds)
Disease acquired by drinking contaminated water (w/human feces)  Bacteria (Vibrio cholerae) colonizes lining of small intestine and produces toxin 2  Toxin modifies G-protein involved in regulating salt & water secretion 1  Disease acquired by drinking contaminated water (w/human feces)  G protein stuck in active form  intestinal cells secrete salts, water  Bacteria (Vibrio cholerae) colonizes lining of small intestine and produces toxin  Infected person develops profuse diarrhea and could die from loss of water and salts 2  Toxin modifies G-protein involved in regulating salt & water secretion  G protein stuck in active form  intestinal cells secrete salts, water Viagra ed person develops profuse diarrhea and could die from loss of water and salts
 Used as treatment for erectile dysfunction
 Inhibits hydrolysis of cGMP  GMP
 Prolongs signal to relax smooth muscle in artery walls; increase blood flow to penis  Used as treatment for erectile dysfunction osis drolysis
= cell s of cGMP
uicide  GMP
sted muscle in artery walls; increase blood flow to penis  Triggered by signals that activate cascade of “suicide” proteins (caspase) Apoptosis = cell suicide
 Protect neighboring cells from damage  Triggered by signals that activate cascade of “suicide” proteins (caspase)  May be involved in some diseases (Parkinson’s, Alzheimer’s)  Protect neighboring cells from damage  Interference may contribute to cancers osis olve
of a d in some
human dise
cellson’s, Alzheimer’s)
Right: WBC undergoing apoptosis – shrinking and forming lobes (“blebs”) Apoptosis of a human white blood cell
poptosis during paw development in the mouse
Right: WBC undergoing apoptosis – shrinking and forming lobes (“blebs”) Effect of apoptosis during paw development in the mouse
Cell Communication
CHAPTER 11
municate?
igeria com
municate?
Cell Signaling
An
 Secreting local regulators (growth factors, neurotransmitters) Long distance (hormones) 3 Stages of Cell Signaling:
1. Reception: Detection of a signal molecule (ligand) coming from outside the cell2. Transduction: Convert signal to a form that can bring about a cellular response 3 Stages of Cell Signaling:
1.
4. Transduction: Convert signal to a form that can bring about a cellular response n : Cellular response to the signal molecule
Transduction
Reception
Response
Transduction
1. Reception
 esponse
Binding between signal molecule (ligand) + receptor is highly specific.
1. Reception
 Binding between signal molecule (ligand) + receptor is highly specific.
 Ligand binds to receptor protein  protein changes SHAPE  initiates transduction  Eg. testosterone or nitric oxide (NO) P Liga
las nd binds
ma Memb to re
ors in  protein changes SHAPE  initiates transduction
G-Protein-Coupled Receptor
Plasma Membrane Receptors
G-Protein-Coupled Receptor
G-Protein-Coupled Receptor
Receptor Tyrosine Kinase
G-Protein-Coupled Receptor
Ligand-Gated Ion Channel
Receptor Tyrosine Kinase
Plasma Membrane Receptors
Ligand-Gated Ion Channel
2. Transduction
ractions relay signals from receptors  target molecules  Protein kinase: enzyme that phosphorylates and activates proteins at next level 2. Transduction
 Phosphorylation cascade: enhance and amplify signal  Cascades of molecular interactions relay signals from receptors  target molecules  Protein kinase: enzyme that phosphorylates and activates proteins at next level  Phosphorylation cascade: enhance and amplify signal Second Messengers
 small, nonprotein molecules/ions that can relay signal inside cell  Eg. cyclic AMP (cAMP), calcium ions (Ca2+), inositol triphosphate (IP Second Messengers
poonprot
nse ein molecules/ions that can relay signal inside cell
 Regulate activity of proteins in cytoplasm 3. Response
An egulate
Examp prot
nicarnin
n on/off genes in nucleus (gene expression)
An Example of Cell Communication
ht
 Signal transduction pathways can be blocked or defective  Drugs (anesthetics, antihistamines, blood pressure meds) lera (anesthetics, antihistamines, blood pressure meds)
Disease acquired by drinking contaminated water (w/human feces)  Bacteria (Vibrio cholerae) colonizes lining of small intestine and produces toxin 2  Toxin modifies G-protein involved in regulating salt & water secretion 1  Disease acquired by drinking contaminated water (w/human feces)  G protein stuck in active form  intestinal cells secrete salts, water  Bacteria (Vibrio cholerae) colonizes lining of small intestine and produces toxin  Infected person develops profuse diarrhea and could die from loss of water and salts 2  Toxin modifies G-protein involved in regulating salt & water secretion  G protein stuck in active form  intestinal cells secrete salts, water Viagra ed person develops profuse diarrhea and could die from loss of water and salts
 Used as treatment for erectile dysfunction
 Inhibits hydrolysis of cGMP  GMP
 Prolongs signal to relax smooth muscle in artery walls; increase blood flow to penis  Used as treatment for erectile dysfunction osis drolysis
= cell s of cGMP
uicide  GMP
d digested muscle in artery walls; increase blood flow to penis  Triggered by signals that activate cascade of “suicide” proteins (caspase) Apoptosis = cell suicide
 Protect neighboring cells from damage  Triggered by signals that activate cascade of “suicide” proteins (caspase)  May be involved in some diseases (Parkinson’s, Alzheimer’s)  Protect neighboring cells from damage  Interference may contribute to cancers osis olve
of a d in some
human dise
cellson’s, Alzheimer’s)
Right: WBC undergoing apoptosis – shrinking and forming lobes (“blebs”) Apoptosis of a human white blood cell
apoptosis during paw development in the mouse
Right: WBC undergoing apoptosis – shrinking and forming lobes (“blebs”) Effect of apoptosis during paw development in the mouse

Source: https://classroom.peoriaud.k12.az.us/sites/LGocza/AP%20Biology%20Resources/Unit%203%20-%20Cell%20Communication%20and%20the%20Cell%20Cycle/Ch.%2011%20Cell%20Communication%20Outline.pdf