cellular communication chapter 11 local communication in what ways do cells communicate locally? in...
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Local communicationLocal communicationIn what ways do cells communicate locally?
In what ways do cells communicate locally?
•In what ways do In what ways do cells cells
communicate communicate over longer over longer distances?distances?
Regulation by chemical messengers
axon
endocrine gland
receptor proteins
target cell
• Neurotransmitters released by neurons
• Hormones release by endocrine glands
receptor proteins
hormone carried by blood
neurotransmitter
Lock & Keysystem
Three Stages of Cell SignalingThree Stages of Cell Signaling
ReceptionReception11
EXTRACELLULAREXTRACELLULARFLUIDFLUID
ReceptorReceptor
SignalingSignalingmoleculemolecule
Plasma membranePlasma membrane
CYTOPLASMCYTOPLASM
11
Fig. 11-6-2Fig. 11-6-2
ReceptionReception11
EXTRACELLULAREXTRACELLULARFLUIDFLUID
ReceptorReceptor
SignalingSignalingmoleculemolecule
Plasma membranePlasma membrane
CYTOPLASMCYTOPLASM
11
Relay molecules in a signal transduction pathwayRelay molecules in a signal transduction pathway
TransductionTransduction22
Fig. 11-6-3Fig. 11-6-3
EXTRACELLULAREXTRACELLULARFLUIDFLUID
Plasma membranePlasma membrane
CYTOPLASMCYTOPLASM
ReceptorReceptor
SignalingSignalingmoleculemolecule
Relay molecules in a signal transduction pathwayRelay molecules in a signal transduction pathway
ActivationActivationof cellularof cellularresponseresponse
ReceptionReception TransductionTransduction ResponseResponse11 22 33
Steroid Hormones:Steroid Hormones:
HormoneHormone(testosterone)(testosterone)
ReceptorReceptorproteinprotein
PlasmaPlasmamembranemembrane
EXTRACELLULAREXTRACELLULARFLUIDFLUID
DNADNA
NUCLEUSNUCLEUS
CYTOPLASMCYTOPLASM
What type of What type of Molecule is Molecule is a steroid?a steroid?
ReceptorReceptorproteinprotein
HormoneHormone(testosterone)(testosterone)
EXTRACELLULAREXTRACELLULARFLUIDFLUID
PlasmaPlasmamembranemembrane
Hormone-Hormone-receptorreceptorcomplexcomplex
DNADNA
NUCLEUSNUCLEUS
CYTOPLASMCYTOPLASM
HormoneHormone(testosterone)(testosterone)
EXTRACELLULAREXTRACELLULARFLUIDFLUID
ReceptorReceptorproteinprotein
PlasmaPlasmamembranemembrane
Hormone-Hormone-receptorreceptorcomplexcomplex
DNADNA
NUCLEUSNUCLEUS
CYTOPLASMCYTOPLASM
HormoneHormone(testosterone)(testosterone)
EXTRACELLULAREXTRACELLULARFLUIDFLUID
PlasmaPlasmamembranemembrane
ReceptorReceptorproteinprotein
Hormone-Hormone-receptorreceptorcomplexcomplex
DNADNA
mRNAmRNA
NUCLEUSNUCLEUS
CYTOPLASMCYTOPLASM
HormoneHormone(testosterone)(testosterone)
EXTRACELLULAREXTRACELLULARFLUIDFLUID
ReceptorReceptorproteinprotein
PlasmaPlasmamembranemembrane
Hormone-Hormone-receptorreceptorcomplexcomplex
DNADNA
mRNAmRNA
NUCLEUSNUCLEUS New proteinNew protein
CYTOPLASMCYTOPLASM
Peptide HormonesNuerotransmittersPeptide HormonesNuerotransmitters
How will the How will the structure of structure of
these moleculesthese molecules cause cause
them to target them to target a cell a cell
differently?differently?
Action of protein hormonesAction of protein hormones
activatesenzyme
activatesenzyme
activates enzyme
ATP
produces an action
P1
2
3
cytoplasm
receptor protein
response
reception
secondarymessengersystem
signal-transduction pathway
acts as 2° messenger
target cell
plasma membrane
binds to receptor protein
proteinhormone
ATPactivatescytoplasmicsignal
cAMP
GTP
activatesG-protein
transduction
adrenal gland
Ex: Action of epinephrine (adrenaline)
Ex: Action of epinephrine (adrenaline)
activatesprotein kinase-A
activatesglycogen phosphorylase
activates adenylyl cyclase
epinephrine
liver cell
releasedto blood
1
25
receptorproteinin cell membrane
cytoplasm
6glycogen
activatesphosphorylase kinase
GTP
cAMP
4
activatesG protein
ATP
glucose
activates GTP
3
signal
transduction
response7
GDP
Ion Channel Receptors
Ion Channel Receptors
SignalingSignalingmoleculemolecule(ligand)(ligand)
GateGateclosedclosed IonsIons
Ligand-gatedLigand-gatedion channel receptorion channel receptor
PlasmaPlasmamembranemembrane
Gate openGate open
CellularCellularresponseresponse
Gate closedGate closed33
22
11
Seen withSeen with neurotransmittersneurotransmitters
Signaling moleculeSignaling molecule
ReceptorReceptorActivated relayActivated relay
moleculemolecule
InactiveInactiveprotein kinaseprotein kinase
11 ActiveActiveproteinproteinkinasekinase
11
InactiveInactiveprotein kinaseprotein kinase
22ATPATP
ADPADP ActiveActiveproteinproteinkinasekinase
22
PP
PPPPPP
InactiveInactiveprotein kinaseprotein kinase
33ATPATP
ADPADP ActiveActiveproteinproteinkinasekinase
33
PP
PPPPPP
ii
ATPATPADPADP PP
ActiveActiveproteinproteinPPPP
PP ii
InactiveInactiveproteinprotein
CellularCellularresponseresponse
Phosphorylation cascade
Phosphorylation cascadeii
First messengerFirst messengerFig. 11-11Fig. 11-11
G proteinG protein
AdenylylAdenylylcyclasecyclase
GTPGTP
ATPATP
cAMPcAMPSecondSecond
messengermessenger
ProteinProteinkinase Akinase A
G protein-coupledG protein-coupledreceptorreceptor
Cellular responsesCellular responses
Benefits of a 2° messenger system
Benefits of a 2° messenger system
Amplification!Amplification!
signal
receptor proteinActivated adenylyl cyclase
amplification
amplification
amplification
amplification
GTP G protein
product
enzyme
protein kinase
cAMP
Not yetactivated
1
2
4
35
6
7
FAST response!
amplification
Cascade multiplier!
EXTRA-EXTRA-CELLULARCELLULAR
FLUIDFLUIDSignaling moleculeSignaling molecule(first messenger)(first messenger)
G proteinG protein
GTPGTP
G protein-coupledG protein-coupledreceptorreceptor Phospholipase CPhospholipase C PIPPIP22
IPIP33
DAGDAG
((secondsecond messengermessenger))
IPIP33-gated-gatedcalcium channelcalcium channel
EndoplasmicEndoplasmicreticulum (ER)reticulum (ER) CaCa2+2+
CYTOSOLCYTOSOL
G proteinG protein
EXTRA-EXTRA-CELLULARCELLULAR
FLUIDFLUIDSignaling moleculeSignaling molecule(first messenger)(first messenger)
G protein-coupledG protein-coupledreceptorreceptor Phospholipase CPhospholipase C PIPPIP22
DAGDAG
IPIP33
(second messenger)(second messenger)
IPIP33-gated-gatedcalcium channelcalcium channel
EndoplasmicEndoplasmicreticulum (ER)reticulum (ER) CaCa2+2+
CYTOSOLCYTOSOL
CaCa2+2+
(second(secondmessengermessenger))
GTPGTP
FigFig
G proteinG protein
EXTRA-EXTRA-CELLULARCELLULAR
FLUIDFLUIDSignaling moleculeSignaling molecule(first messenger)(first messenger)
G protein-coupledG protein-coupledreceptorreceptor Phospholipase CPhospholipase C PIPPIP22
DAGDAG
IPIP33
(second messenger)(second messenger)
IPIP33-gated-gatedcalcium channelcalcium channel
EndoplasmicEndoplasmicreticulum (ER)reticulum (ER) CaCa2+2+
CYTOSOLCYTOSOL
VariousVariousproteinsproteinsactivatedactivated
CellularCellularresponsesresponses
CaCa2+2+
(second(secondmessenger)messenger)
GTPGTP
Fig. 11-14Fig. 11-14GrowthGrowth factorfactor
ReceptorReceptor
PhosphorylationPhosphorylationcascadecascade
ReceptionReception
TransductionTransduction
ActiveActivetranscriptiontranscription
factorfactorResponseResponse
PP
InactiveInactivetranscriptiontranscription
factorfactor
CYTOPLASMCYTOPLASM
DNADNA
NUCLEUSNUCLEUS mRNAmRNA
GeneGene
Fig. 11-15Fig. 11-15
ReceptionReception
TransductionTransduction
ResponseResponse
Binding of epinephrine to G protein-coupled receptor (1 molecule)Binding of epinephrine to G protein-coupled receptor (1 molecule)
Inactive G proteinInactive G protein
ActiveActive G protein (10G protein (1022 molecules molecules))
Inactive adenylyl cyclaseInactive adenylyl cyclaseActive adenylyl cyclase (10Active adenylyl cyclase (1022))
ATPATP
Cyclic AMP (10Cyclic AMP (1044))
Inactive protein kinase AInactive protein kinase AActive protein kinase A (10Active protein kinase A (1044))
Inactive phosphorylase kinaseInactive phosphorylase kinase
Active phosphorylase kinase (10Active phosphorylase kinase (1055))
Inactive glycogen phosphorylaseInactive glycogen phosphorylase
Active glycogen phosphorylase (10Active glycogen phosphorylase (1066))
GlycogenGlycogenGlucose-1-phosphateGlucose-1-phosphate
(10(1088 molecules) molecules)
Homology in hormonesHomology in hormones
prolactin
mammals
milkproduction
birds
fatmetabolism
amphibians
metamorphosis& maturation
fish
salt &water
balance
growth& development
What does this tell you about these hormones?
growthhormone
same gene familygene duplication?
How could these hormones have different effects?
How can 1 signal
molecule have
multiple responses?
How can 1 signal
molecule have
multiple responses?
Let’s go to the Video!
Fig. 11-20aFig. 11-20a
Ced-9Ced-9protein (active)protein (active)inhibitsinhibits Ced-4 Ced-4
activityactivity
MitochondrionMitochondrion
Ced-4Ced-4 Ced-3Ced-3ReceptorReceptorfor death-for death-signalingsignalingmoleculemolecule
Inactive proteinsInactive proteins
(a) No death signal(a) No death signal
Fig. 11-20bFig. 11-20b
(b) Death signal(b) Death signal
Death-Death-signalingsignalingmoleculemolecule
Ced-9Ced-9(inactive)(inactive)
CellCellformsformsblebsblebs
ActiveActiveCed-4Ced-4
ActiveActiveCed-3Ced-3
ActivationActivationcascadecascade
OtherOtherproteasesproteases
NucleasesNucleases