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Flashcards in Final 3 Deck (119):
1

Exocytosis that requires an external signal, a specific sorting signal on the vesicles, a clathrin coat, and increase of calcium

Regulated exocytosis

2

Exocytosis that serves to release components of ECM or just deliver newly PM proteins

Constitutive exocytosis

3

Why would a lysosome deposit its contents outside the cell?

Defense mechanism

4

Mark organelles and membrane domains in late secretory pathway

Phsophoinositides

5

What adds a phosphate onto the inositol ring of phosphatidylinositol

Lipid kinase

6

What removes a phosphate on the inositol ring of phsophatidylinositol?

Lipid phosphatase

7

How is neurotransmitter secretion very rapid?

Regulated by calcium

8

WHere does proteolytic processing occur?

Late Golgi

9

What holds SNARE proteins "partially-zipped up"

Complexin

10

Calcium snesor protein that allows the release of vesicle content by membrane fusion

Syanptotagmin

11

Example of compound exocytosis which provides a very large release of material over a short period of time

Histamines from mast cells

12

What kind of cells contain GLUT4

Insulin responsive cells (adipose, muscle)

13

Two compositionally distinct and different PMs

apical, basolateral

14

Where is the decision of what membrane a vesicle should go to in a polarized cell made?

TGN or all go to one membrane, and undergo endocytosis and sorting

15

How is iron transported into the cell?

Transferrin receptor

16

Fluid-phase endocytosis for uptake of fluids and solutes

Pinocytosis

17

Coat protein responsible for majority of vesicular traffic between TGN and PM

Clathrin

18

Composition of clathrin coats

Triskelion: 3 heavy chains and 3 light chains

19

Coat used for pinocytosis

Caveolae

20

Polyhedral superstructures that clathrin triskelion form

Cages

21

GTPase that constricts the neck of a newly formed coated pit to form a vesicle

Dyanmin

22

How is a clathrin coat removed?

HSP70 family of chaperones and its ATPase actiity

23

Storage form of cholesterol and primary vehicle for cholesterol transport in blood

Low-density lipoprotein (LDL)

24

Where in the cell are LDL particles broken down?

Lysosome

25

Clusters of LDL receptors in the PM

Coated pits

26

What does the cytosolic portion of LDL receptors do once associated with clathrin adapters?

Nucleates binding of a few clathrin triskelions to form coated pit

27

What happens to LDL receptors after endocytosis

Recycled into PM

28

How is LDL freed from its receptor?

pH change due to endosome

29

Separates and sequesters material to be degraded from material to be recycled

Mulitvesicular bodies (MVBs)

30

How are proteins recognized as needed to be degraded in MVBs?

Monoubiquination

31

Cytosolic protein complex that results in a specific accumulation of tagged protein into endosomal membrane invagination

ESCRT proteins

32

Ingestion of large particles restricted to macrophages and neutrophils

Phagocytosis

33

Movement of endocytosed material across the entire clel in membrane enclosed compartment

Transcytosis

34

What do cells unstimulated by insulin do?

Import glucose through the transporter

35

What do cells stimulated by insulin do?

Release glucose through exocytosis

36

Chemical bond formation linked to membrane transport process

Chemiosmotic coupling

37

High-energy electrons from NADH used to set up a proton gradient across IMM

Electron transport chain

38

Beta-barrel proteins on OMM

Porin

39

What size molecules are porins permeable to?

<5,000 daltons

40

Location of TCA and the source of NADH

Matrix

41

What is the movement of mitochondria mediated by?

Microtbulues

42

What generates more energy, FADH2 or NADH?

NADH

43

How many electrons does a NAD+ accept?

2

44

iElectrochemical gradient of protons in the mitochondria

Proton motive force (PMF)

45

What is the real name for ATP synthesis via electron transport chain

Oxidative phosphorylation

46

What does the complete oxidation of one glucose yield?

2 NADH, 2 ATP, 2 pyruvate

47

What are 2 pyruvates oxidized to?

8 NADH, 2 FADH, 2 GTP

48

How many ATPs are produced per glucose?

30

49

What kind of pump is ATP synthase?

F-type ATPase

50

Mobile electron carrier that can carry 1 or 2 electrons and is embedded into the membrane

Uniquinone

51

How is uniquinone embedded into the membrane?

Isoprenoid

52

What does uniquinone shuttle electrons to and from

From complex I to complex III

53

Soluble protein with bound heme group

Cytochrome c

54

What does cytochrome c shuttle electrons to and from

complex III to complex IV

55

Name of complex I

NADH dehydrogenase

56

Name of complex III

Cytochrome bc1

57

Name of complex IV

Cytochrome oxidase

58

Uncouple electron transport from ATP synthesis

Proton ionophores

59

2 examples of uncouplers

DNP, FCCP

60

Part of ATP synthesase that is intermembrane

F0

61

Part of ATP synthesase that surrounds stalk with 6 subunits

F1

62

Name of complex II

Succinate dehydrogenase

63

What does complex II do?

Accepts two electrons from succinate

64

Signaling to self

Autocrine

65

Local signaling to a close group of cells

Paracrine

66

Signaling distributed throughout bloodstream

Endocrine

67

Signaling based on physical contact

Contact dependent signaling

68

Difference between endocrine and synaptic signaling

Endocrine are long-livd

69

Most direct path of ligand signaling

Intracellular receptors (e.g. steroid hromones)

70

Why are steroid hormones able to use intracellular receptors?

They are lipid soluble so can pass right through PM

71

4 examples of small G-proteins

Ras, Rab, Rho, Ran

72

How many transmembrane domains do G-protein receptors have?

7

73

What happens when GDP-bound g-proteins are turned on?

ALpha dissociates from beta-gamma

74

What is the alpha subunit of g-proteins postranslationally modified by?

Myristic acid

75

What is the gamma subunit of g-proteins postranslationally modified by?

Polyisoprenoid

76

Enzymes that have their activity modulated by interaction with a g-protein

G-protein effectors

77

Enzyme that converts ATP to cAMP

Adenylyl cylcase

78

cAMP initiates a protein kinase cascade by activating what?

Protein Kinase A (PKA)

79

3 functions of cAMP

cortisol secretion from adrenal cortex, glycogen breakdown in muscle and liver, triacylglycerol breakdown in fat

80

In muscles, what does PKA activation lead to?

Activation of phosphorylase kinase, leading to glycogen breakdown

81

What gene regulatory protein does PKA activate?

cAMP regulatory element binding protein (CREB)

82

What does CREB do?

Changes transcription of genes that contain a cAMP regulatory element (CRE)

83

Enzyme that cleaves (PI(4,5)P2) into diacylglycerol and IP3

Phospholipase C-beta

84

What does formation of IP3 do?

Opens Ca channel and releases Ca into the cytosol from ER

85

After opening by IP3, what does released Ca bind to?

Protein Kinase C (PKC)

86

Where are Ca concentrations kept high?

ER and outside cell

87

Regulatory Ca binding protein for muscle contraction

Troponin C

88

Calcium sensor for neutrotransmission

Synaptotagmin

89

Multipurpose calcium receptor involved in many responses

Calmodulin

90

Structure of calmodulin

Four EF hands (ca binding domains)

91

Main targets of calmodulin

Protein kinases

92

Protein kinase involved in smooth muscle contraction

Myosin light chain kinase

93

Protein kinase inolved in glycogen breakdown

Phosphorylase kinase

94

Calcium-dependent protein kinase whose activity persists even after the calcium signal has faded

CaM Kinase II

95

How does ca-calmodulin activate CaM Kinase II?

BInds to inhibitory domain, liberating it

96

Single-span membrane proteins that oligomerize in response to ligand binding

Receptor tyrosine kinases (RTKs)

97

What kind of protein is the insulin receptor?

Disulfide-linked heterotetramer

98

What kind of protein are RTKs?

Enzymes

99

What is the typical method of oligomerization that RTKs undergo?

Dimerization

100

What does receptor oligomerization of RTKs lead to?

Activation of kinase domain by autophosphorylation

101

What happens once RTKs become autophosphorylated?

Receptor increases its kinase activity towards substrates

102

Binds specifically to phosphotyrosine in RTKs

Src Homology Region 2 domain (SH2)

103

Binds to proline rich motifs in RTKs

Pleckstrin Domain (PH)

104

What membrane lipid do PH domains associate with?

PIP3

105

3 enzymes recruited to PDGF receptor by its SH2 domain

PI3 kinase, Ras GAP, PLC-gamma

106

Primary target of Ras

Raf-1

107

What cascade is Raf-1 the first element of?

MAP kinase

108

Signal that tells a cell to divide

Mitogen

109

Through what molecule does Ras activation generate new membrane lipids?

PI 3-kinase

110

Receptors that rely on its associated kinases to cross phosphorylate one another

Tyrosine kinase associated receptors

111

Target of Jak kinases

STAT

112

Role of STAT

Regulator of gene expression

113

What kind of receptors do TGF-beta use?

Serine/threonine kinases

114

Activated TGF-beta activates what kind of gene regulatory proteins?

Smad

115

Ligands for receptor guanylyl cyclases

ANP, BNP

116

What do ANP and BNP do?

Regulate salt and water balance

117

What does cGMP activate?

PKG

118

Membrane bound singaling protein expressed on developing nerve cells

Delta

119

Receptor of Delta

Notch