Cell signaling part 2 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

transmembrane proteins with their ligand-binding domain on the outer surface

A

enzyme-coupled receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How is ECR different from GPCR differ in terms of cystolic domain?

A

Cystolic domain has intrinsic enzyme activity or associates directly with enzyme

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Most common type of enzyme-coupled receptors

A

receptor tyrosine kinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How many Human RTKs?

A

60 human RTKs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many structural subfamilies in 60 human RTKs

A

20

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

the binding of the signal protein to the ligand -binding domain on the extracellular side of the receptor

A

activates the tyrosine kinase domain on the cytosolic side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Activation of cytoplasmic kinase domains of RTKs

A

dimerization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

dimerization brings the kinase domains close to each other in an orientation that allows them to phosphorylate each other on specific tyrosines

A

Insulin receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

activate kinase domains

A

Promoting conformational change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

families of monomeric GTPases

  • relay signals from cell-surface receptors
A

Ras superfamily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

can coordinately spread the signal along several distinct downstream signaling pathways

A

Signaling Hub

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Three major, closely related Ras proteins in humans

A

H-, K-, and N-ras

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

between two distinct conformational states

A

Molecular switch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does Ras activity acts as molecular switches

A

GTP: on (active)
GDP: off (Inactive)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

dissociation of GDP; uptake of GTP, activatingRas

A

Ras guanine nucleotide exchange factors (Ras-GEFs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

hydrolysis of bound GTP, inactivating Ras

A

Ras GTPase-activating proteins (Ras-GAPs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Are resistant to Ras GAPs

A

Hyperactive mutatant forms of Ras

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

GEF that mediates Ras activation by RTKs

A

Sevenless (Sev)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Genetic screens for components of this signaling pathway led to the discovery of a Ras GEF

A

Son-of-sevenless (Sos)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

which is an adaptor protein that links the Sev receptor to the Sos protein

A

Grb2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

promotes the Ras activation

A

Sos

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Short-lived signaling events that is activated by RTKs

A
  • Tyrosine phosphorylations and Ras activation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

relays the signal downstream by phosphorylation

A

MAP kinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Three componens of MAP kinase module

A
  • MAPK (Erk)
  • MAPKK (Mek)
  • MAPKKK (Raf)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

MAP kinase module

A

mitogen-activated protein kinase
module

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

MAP Kinase module full name

A

mitogen-activated protein kinase module

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

enters the nucleus and phosphorylates transcription regulatory complex

A

erk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What does eark activates?

A

Immediate early genes (Transcription regulators)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

convey signals from the cell surface to the nucleus and alters the pattern of gene expression

A

Ras-MAP-kinase signaling pathways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

mediates different responses in the same cell

A

MAP kinase modules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

help prevent cross-talk between parallel MAP kinase modules

A

Scaffold proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

five parallel MAP kinase modules

A
  • 12 MAP kinases
  • 7 MAPKKs
  • 7 MAPKKK
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

activated by different kinds of cell stresses (UV, heat shock, osmotic stress)

A

JNK and p38

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

reduces the opportunities for amplification and spreading of the signal to different parts of the cell

A

Scaffold strategy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

the other class of Ras superfamily GTPases that relays signals from cell-surface receptors

A

Rho Family

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

regulate both the actin and microtubules cytoskeleton controlling cell shape, polarity, motility, and adhesion

A

Rho family monomeric GTPases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Family members of Rho family

A

Rho, Rac, and Cdc42

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

often bound to guanine nucleotide dissociation inhibitors (GDIs) in the cytosol

A

inactive Rho family GTPases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

provides an example of how RTKs can activate a Rho GTPase

A

ephrin family

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Ephrins bind and thereby activate members of the

A

Eph family of RTKs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

migrating tip of the axon

A

growth cone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

activates the Eph receptor

A

binding of ephrin pritein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

repelling them from inappropriate regions and keeping them on track

A

growth cone collapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

activate RhoA (Rhoa-GTP)

A

Rho-GEF ephexin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Major changes in the behavior of a cell tend to depend on

A

Gene expression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

carry out their effects by initiating signaling pathways that change the activities of transcription regulators

A

Many extracellular signaling molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

control in gene expression

A

Less common

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

pathways that depend on ___ ___

A

regulated proteolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What does regulated proteolysis control?

A

control activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What does transcription regulators control?

A

Location of latent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

gene expression controlled by

A

circadian rhythm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q
  • used widely in animal development.
  • controlling cell face choices and regulating pattern formation and continual renewal of tissues
A

Notch protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Notch receptor protein is known for its role in?

A

the production of Drosophila neural cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

contact dependent

A

Lateral inhibition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

binds to Notch receptor protein

A

Delta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

when a precursor cell commits to becoming a ___ cell → signal to its ___ ___ not to do the same

A

neural
immediate neighbors

57
Q

single-pass transmembrane protein that requires proteolytic processing to function; latent transcription regulator

A

Notch proteins

58
Q

Binding of ___ → plasma- membrane-bound ___ cleaves
off the cytoplasmic tail of Notch → tail
translocates into the nucleus to
activated the transcription of ___ ___ ___

A

Delta
protease
Notch response genes

59
Q

tail fragment acts by binding to a ____ ___ → converting from transcriptional repressor into a ___ ___

A

DNA-binding protein
transcriptional activator

60
Q

Three successive proteolytic cleavage steps of Notch

A
  • 1st – normal biosynthesis
  • 2nd – binding of Delta to Notch
  • 3rd – cutting free the cytoplasmic tail of the activated receptor
61
Q

final cleavage of the Notch tail

A

γ-secretase

62
Q

are secreted signal molecules that act as local mediators and morphogens

A

Wnt proteins

63
Q

Where is Wnt proteins discovered?

A

Flies and Mice

64
Q

morphogen in wing development

A

Drosophila - Wingless (Wg) gene

65
Q

promoted the development of breast tumors when activated by the integration of a virus next to it

A

in mice – Int1 gene

66
Q

latent transcription of regulatory β-catenin

A

Wnt/β-catenin pathway

67
Q

coordinates the polarization of cells in the plane of a developing of epithelium

A

planar polarity pathway

68
Q

binds to β-catenin and keeps it out of the nucleus while promoting its degradation

A

Degradation complex

69
Q

phosphorylates the β-catenin

A

casein kinase 1 (CK1) and glycogen synthase kinase 3 (GSK3)

70
Q

hold the protein complex together

A

axin and Adenomatous polyposis coli (APC)

71
Q

is a seven-pass transmembrane protein that resembles GPCRs in structure but does not generally work through the activation of G proteins

A

Frizzled

72
Q

is a relatively simple single-pass transmembrane protein

A

LRP (LDL-receptor-related protein)

73
Q

disrupting the β-catenin degradation complex in the cytoplasm

A

Axin

74
Q

inhibitory complex: LEF1/TCF family bound to a co-repressor protein of the Groucho family

A

no Wnt signaling

75
Q

coactivator; inducing the transcription of the Wnt target genes

A

with Wnt signal

76
Q

important regulator of cell growth and prolifereation

A

Myc

77
Q

Causes development of Colon Cancer

A

Mutation in APC gene

78
Q

mutation in Apc gene- occure in ___ of human colon cancers

A

80%

79
Q

How does APC gene causes cancer?

A

β-catenin accumulates in the nucleus and stimulates the transcription of c-Myc and other Wnt target genes

80
Q
  • secreted signal molecules and act as local mediators and morphogens
  • Trigger a switch from transcriptional repression to transcriptional activation
A

Hedgehog proteins

81
Q

Where is hedgehog protein first discovered?

A

Drosophila

82
Q

What does mutation of hedgehog gene do to drosophila

A

Produces a larva covered with spiky processes

83
Q

Genes encoding hedgehog proteins

A

Sonic, Desert, Indian hedgehog

84
Q

Where is hedgehog pathway located

A

Primary cilium

85
Q

Hedgehog proteins is mediated by a latent transcription regulator called?

A

Cubitus interruptus (Ci)

86
Q

What if hedgehog signal is absent?

A
  • Ci is ubiquitylated and proteolytically cleaved in proteasomes
87
Q

acts as a transcriptional repressor (in hedgehog proteins)

A

Ci from smaller fragements

88
Q

processing of Ci protein depends on

A
  • PKA (protein kinase A)
  • two kinases (GSK1 and CK1)
89
Q

keep unprocessed Ci out of the nucleus

A

Scaffold protein Costal2

90
Q

Transmembrane proteins of hedgehog

A

Patched
iHog
Smoothened

91
Q

Patched keep Smoothened sequestered and inactive

A

Absence of the signal

92
Q

inhibits the activity of Patched and induces endocytosis and degradation (in hedgehog proteins)

A

Binding of hedgehog to iHog and Patched

93
Q

recruits protein complex Ci, Fused, and Costal2

A

Smoothened translocated to the plasma membrane

94
Q

– increase Patched proteins that inhibits further Hedgehog signaling –negative feedback

A

Genes for patched

95
Q
  • latent transcription regulators; stress, inflammatory, and innate immune responses
  • excessive signaling found in human cancer
A

NFkB-Dependent signaling pathway

96
Q

the Drosophila NFkB family member

A

Dorsal

97
Q

has a crucial role in specifying the dorsal–ventral axis of the developing fly embryo

A

Dorsal

98
Q

The cell-surface receptors that activate the NFKB signaling pathways in animal cells

A
  • Toll receptors in Drosophila
  • Toll-like receptors in vertebrates
99
Q

Toll receptors in Drosophila and Toll-like receptors in vertebrates do?

A

recognize pathogens and activate this pathway in triggering innate immune responses

100
Q

Proteins in NFkB

A

RelA, RelB, c-Rel, NFKB1, and NFKB2

101
Q

– inhibitory protein; bind tightly to the dimers and hold them in an inactive state within the cytoplasm of unstimulated cells

A

IkB

102
Q

activated the gene that encodes IκBa

A

NFkB

103
Q

negative feedback produces two types of NFκB responses; induce different patterns of gene expression

A

TNFa(alpha)-induced responses

104
Q

turns on gene A

A

short exposure to TNF produces single, short pulse of NFκB activation

105
Q

produces oscillation in NFκB activation; turns on both genes

A
  • sustained exposure
106
Q

hydrophobic signal molecules that diffuse directly across the plasma membrane and bind to intracellular receptors (transcription regulators)

A

nuclear receptor superfamily

107
Q
  • bind to specific DNA sequences adjacent to the genes that the ligand regulates
  • ligand binding alters the conformation of the receptor protein
A

Nuclear receptors

108
Q

internal oscillators that control diurnal rhythms

A

Circadian clocks

109
Q

controls our diurnal cycles of sleeping and waking, body temperature, and hormone release

A

SCN (Suprachiasmatic nucleus)

110
Q

Process of releasing melatonin

A
  • SCN cells receives signal cues from the retina
  • (send information to other brain areas and;) pineal gland
  • rest of the body by releasing the hormone melatonin
111
Q

generally depend on negative feedback loops

A

Circadian clocks

112
Q

coordinate their activities in response to the changing conditions of light, dark, and temperature

A

Signaling in plants

113
Q

what plants and animals use for signaling

A

Nitric oxide
cyclic GMP
Ca2+
Rho family GTPases

114
Q

The clylic phosphae that is NOT used by plants

A

Cyclic AMP

115
Q

cell-surface receptors in plants are

A

enzyme-coupled

116
Q

Plants rely largely on a great diversity of transmembrane ______ ___

A

receptor serine/threonine kinases

117
Q

The most abundant types of these receptors have a tandem array of extracellular leucine-rich repeat structures and are therefore

A

Leucine-rich repeat (LRR) receptor kinases

118
Q

How many LRR receptor kinases in Arabidopsis?

A

175 LRR receptor kinases

119
Q

Plants synthesize a class of steroids that are called

A

Brassinosteroids

120
Q

help to coordinate plant development

A

plant growth regulators (plant hormones)

121
Q

examples of plant hormones

A
  • ethylene
  • auxin
  • cytokinin
  • gibberellins
  • abscisic acid
  • brassinosteroids
122
Q

are all small molecules made by most plant cells

A

Growth regulators

123
Q

small gas molecue

A

Ethylene

124
Q

How does etyhylene influence plant development?

A
  • promote fruit ripening
  • leaf abscission
  • plant senescence
125
Q

Where are ethylene receptors located?

A

Endoplasmic reticulum

126
Q

copper-containing ethylene binding domain ; that interacts with a cytoplasmic regions

A

CTR1

127
Q

CTR1 _____ the ubiquitylation and degradation in proteasomes of nuclear transcription regulator ____

A

stimulates
EIN3

128
Q

activate the transcription of the large number of ethylene-responsive genes

A

EIN3

129
Q
  • indole-3-acetic acid
  • It helps plants grow toward light, grow upward rather than branch out, and grow their roots downward.
A

Auxin

130
Q

Transport system of Auxin

A
  • Specific plasma memebrane-bound influx transporter proteins
  • efflux transporter proteins
131
Q

light- sensitive proteins

  • covalently attached light-absorbing chromophore, which changes its shape in response to light and then induces change in the protein’s conformation
A

Photoproteins

132
Q

red (activates) and far-
red light (inactivates)

A

Phytochromes

133
Q

phototropism; tendency of plants to grow toward light

A

Phototropin

134
Q

flavoproteins; sensitive to blue light

A

cryptochromes

135
Q

blue-light-sensitive enzymes of cryptochromes

A

Photolyases

136
Q

phototropism; tendency of plants to grow toward light

A

Phototropin

137
Q

Flavoproteins; sensitive to blue light

A

Cryptochromes

138
Q

What does cryptochromes do?

A
  • Invovled in repair of ultraviolet-induced DNA damage
139
Q

Importance of cryptochromes in animals

A

role in circadian clocks