Powerpoint 4 Chapter 14

Question 1

epinephrine receptor

Answer 1

beta-andrenergic

Question 2

epinephrine causes

Answer 2

energy-store mobilization

Question 3

insulin causes

Answer 3

increased glucose uptake

Question 4

EGF causes

Answer 4

expression of growth-promoting genes

Question 5

signal transduction steps

Answer 5

1) release of primary messenger 2) reception of primary messenger 3) transduction. receptor releases second messengers 4) Activation of effectors 5) termination

Question 6

effector

Answer 6

controls channels or pumps, enzymes, or proteins that control gene expression

Question 7

common second messengers

Answer 7

cAMP, Ca++, inositol, DAG

Question 8

three receptor types of signalling pathways

Answer 8

G-protein coupled, enzyme linked, ligand gated ion channels

Question 9

enzyme linked receptors have ? or ? activity

Answer 9

cytoplasmic tyrosine kinase, guanylyl cyclase

Question 10

G-protein receptors AKA

Answer 10

7-transmembrane helix receptors

Question 11

7TM receptors only found in ?

Answer 11

eukaryotes

Question 12

first member of the 7TM family discovered

Answer 12

Rhodopsin

Question 13

?% of therapeutic drugs target 7TM receptors

Answer 13

50

Question 14

bind to andrenergic receptors to activate

Answer 14

agonists

Question 15

inhibit actvation

Answer 15

antagonists

Question 16

types of andrenergic receptors

Answer 16

alpha 1 and 2, beta 1,2 and 3

Question 17

consequence of ligand binding to 7TM

Answer 17

conformational change converts receptor into a guanine nucleotide exchange factor. activation of G protein trimer (of alpha, beta, and gamma subunits) because the alpha subunit binds guanyl nucleotides causes the alpha subunit to dissociate.

Question 18

activation of adenylate cyclase by alpha subunit of G-protein causes

Answer 18

conversion of ATP into cAMP

Question 19

beta-andrenergic receptor is a type of ?

Answer 19

7TM receptor

Question 20

epinephrine binding to beta-andrenergic receptor resulting pathway

Answer 20

activation, conformatinal change. activation of G-protein and dissociation of alpha subunit. protein interaction with adenylate cyclase activates. enzymatic reaction to form cAMP. activated protein kinase A.

Question 21

pathway linking activated Protein Kinase A to mobilization of stored CHO

Answer 21

PKA activates phosphoryl kinase. phosphoryl kinase activates phosphorylase. phosphorylase initiates synthesis of glucose from glycogen.

Question 22

four ways of regulating signaling

Answer 22

at the receptor (agonist/antagonist, desensitization), the g-protein itself, second messenger, protein kinases

Question 23

receptors turned of by?

Answer 23

dissociation of signal molecule

Question 24

receptors desensitized by?

Answer 24

phosphorylation of cytoplasmic C-terminal and binding of b-arrestin

Question 25

G-proteins are timers because..

Answer 25

they turn off by hydrolyzing GTP to GDP and Pi

Question 26

cAMP is degraded by

Answer 26

soluble phosphodiesterase

Question 27

ACE inhibitors are important for?

Answer 27

lowering blood pressure

Question 28

ACE stands for

Answer 28

angiotensin converting enzyme

Question 29

angiotensin is produced by ACE and causes

Answer 29

vasoconstriction by activating a G-protein that activates Phospholipase C

Question 30

signaling via phospholipase C releases these two secondary messengers from cleavage of PIP2

Answer 30

IP3, DAG

Question 31

Protein kinase C can be artificially activated by addition of ?

Answer 31

phorbol esters that bind to DAG site and a calcium ionophore

Question 32

IP3 causes

Answer 32

rapid release of Ca++

Question 33

PKC ordinarily activated by ?

Answer 33

DAG

Question 34

fertilization of an egg causes a wave of ? in the cytoplasm. It can be monitored by fluorescence.

Answer 34

Ca++

Question 35

common Ca++ binding site

Answer 35

EF Hand motif

Question 36

two important Ca++ binding proteins

Answer 36

calmodulin and annexins

Question 37

calmodulin activation causes

Answer 37

exposing of hydrophobic patches that bind target proteins. ex. activation of CaM kinase

Question 38

CaM kinase function

Answer 38

phosphorylates target proteins that regulate metabolism, ion permeability, and neurotransmitter release

Question 39

common signals of enzyme linked receptors

Answer 39

insulin, EGF

Question 40

insulin receptor structure

Answer 40

dimer of alpha-beta subunits. insulin binding site is between the two alpha subunits outside of cell

Question 41

result of insulin binding to insulin receptor

Answer 41

autophosphorylation followed by phosphorylation of target proteins such as insulin receptor substrates

Question 42

the insulin receptor is a ? kinase

Answer 42

tyrosine

Question 43

the insulin receptor substrates share (3)

Answer 43

pleckstrin domain, SH2 domains, four Tyr phosphorylation sites

Question 44

pleckstrin domain function

Answer 44

binds PIP2

Question 45

SH2 domain function

Answer 45

binds phosphotyrosine

Question 46

Akt-2, activated by insulin receptor phosphorylation cascade, is a protein kinase that ?

Answer 46

stimulates fusion of GLUT4 receptor vesicles to plasma membrane

Question 47

phosphotyrosine of IRS-1 recruits ?

Answer 47

cytosolic PI3 kinase

Question 48

? domain of PI3 kinase binds to IRS-1

Answer 48

SH2

Question 49

binding of PI3 kinase to IRS-1 allows ?

Answer 49

it to interact with its membrane substrate

Question 50

PI3 kinase produces the secondary messenger ?

Answer 50

PIP3

Question 51

phosphatases ? and ? convert PIP3 back to PIP2

Answer 51

PTEN and SHIP

Question 52

insulin signaling pathway

Answer 52

activated receptor. phosphorylated IRS proteins. localized PI3 kinase. production of PIP3. activated PIP3 dependent protein kinase. activated Akt protein kinase. increased glucose transporter on cell surface.

Question 53

? removes activated receptor

Answer 53

receptor recycling

Question 54

Akt is dephosphorylated by ?

Answer 54

PHLPP

Question 55

EGF binding to its monomeric receptor causes

Answer 55

a conformatinal change that leads to dimerization

Question 56

dimerization of EGF receptor activates ?

Answer 56

autophosphorylation of tyrosines in the c-terminal tail

Question 57

phosphotyrosine tails of EGF receptor recruit ?

Answer 57

adaptor proteins like Grb-2

Question 58

SH3 domain of Grb-2 binds to ?

Answer 58

proline-rich portions of the protein SOS

Question 59

SOS

Answer 59

guanine nucleotide exchange factor protein that activates a small G protein called Ras

Question 60

Ras initiates ?

Answer 60

phosphorylation cascade by activation of Raf

Question 61

oncogene

Answer 61

leads to cancerlike characteristics in susceptible cell types

Question 62

c-Src vs v-Src

Answer 62

c-Src contains key tyrosine residue near its C-terminal that when phosphorylated binds to upsteam SH2 region. v-Src lacks this and can not be turned off and leads to unregulated cell growth.

Question 63

? mutations are the most common mutations in tumors

Answer 63

Ras

Question 64

overexpression of EGF receptor leads to ?

Answer 64

dimerization in the absence of EGF

Question 65

? block dimerization of EGF receptor

Answer 65

monoclonal antibodies

Question 66

SH2 and SH3 domains of Src work together to inhibit

Answer 66

tyrosine kinase activity

Question 67

90% of patients with chronic myelogenous leukemia have a chromosomal defect that ?

Answer 67

activates a tyrosine kinase bcr-abl

Question 68

? is an effective treatment for chronic myelogenous leukemia

Answer 68

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