Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Cell Biology > Final 2 > Flashcards

Final 2 Flashcards

1
Q

Where do proteins without a sorting signal end up?

A

Stay in cytosol

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

Gated transport of the nucleus through what?

A

Nuclear pore complexes

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

3 types of intracellular transport

A

Gated, transmembrane, vesicular

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

2 types of sorting signals

A

Signal sequences, signal patches

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

How long are sorting signals?

A

15-60 continuous residues

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

How are signal sequences removed from a protein?

A

Signal pepidases

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

Proteins that make up a NPC

A

Nucleoporins

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

About how many NPCs does a mammalian cell contain?

A

3000-4000

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

True or false: nuclear proteins can be transported through a pore complex while folded

A

True

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

Binding sites for nuclear import receptors

A

F-G repeats

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

Provides energy for concentration of particular proteins on one side of the nuclear envelope

A

Ran

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

What kind of molecule is Ran

A

GTPase

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

Triggers hydrolysis of ATP, converting Ran-GTP to Ran-GDP in the cytosol

A

GAP (GTPase-activating protein)

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

Promotes the exchange of GDP for GTP, converting Ran-GDP to Ran-GTP

A

GEF (Guanine exchange factor)

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

Ran-____ is primarily in the cytosol; Ran-____ is primarily inside the nucleus

A

GDP, GTP

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

Where are mitochondrial signal sequences?

A

Amino-terminus

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

Completes mitchondrial import by repeated cycles of ATP hydrolysis

A

HSP70

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

Helps insert membrane proteins into outer membrane

A

TOM (translocase of outer membrane)

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

Spans both mitochondrial membranes and mediates translocation of proteins in to the matrix space

A

TIm23

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

Mediates the insertion of a subclass of inner membrane proteins

A

TIM22

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

Mediates the insertion of inner membrane proteins synthesized in the mitochondrial matrix

A

OXA complex

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

Keeps mitochondrial precursors in their unfolded confromation using ATP

A

HSP70

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What acts as a stop-transfer sequences that prevents further translocation across IMM

A

Hydrophobic signal

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

True or false: all peroxisome proteins must be imported from the cytosol

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
House oxidative enzymes such as oxidases that produce peroxide
Peroxisomes
26
How are peroxisomes inolved in lipid metabolism?
Degrade fatty acids by beta oxidation
27
True or false: proteins imported into peroxisomes can be imported fully-folded
True
28
Proteins involved in the generation or maintenace of peroxisomes
Peroxins
29
helps insert and fold beta-barrels in the OMM
SAM
30
Protein that binds to emergent signal sequences, halts translation, and targets the complex to the ER
Signal recognition particle (SRP)
31
How are SRPs recognized on the ER membrane?
SRP receptor
32
Protein translocation channel of the ER
Sec61 complex
33
ER chaperone that binds and releases proteins to maintain directionality
BiP
34
Protease that removes signal sequences in the ER membrane
Signal peptidase
35
-COOH-terminus in the cytoplasm
Type I membrane protein
36
-NH3-terminus in the cytoplasm
Type II membrane protein
37
What protein charges typically remain in the cytosol?
Positive
38
An ER lumenal Hsp70 homolog that binds to unfolded proteins and prevents aggregation
BiP
39
Calcium-binding proteins that are lectins that bind to oligosaccharides on incompletely folded proteins and prevents aggregation
Calnexin, calreticulin
40
Enzyme that aids in folding by helping correct disulfide bond formation in newly synthesized proteins
Protein disulfide isomerase (PDI)
41
Covalent addition of sugars to proteins
Glycosylation
42
Attachment of sugar to the hydroxyl group of serine on threonine
O-linked glycosylation
43
Attachment of sugar ot the amide nitrogen of asparagine
N-linked glycoslyation
44
Enzyme that transfers an oligosaccharide to the Asn residue
Oligosaccharyl transferase (OST)
45
Lipid scaffold that helps transfer sugars to proteins
Dolichol
46
Why are sugars added to proteins in the ER
As a tag to mark the state of protein folding
47
ER resident enymze that removes glucose in order to allow a protein to continue folding
Glucosidase
48
Adds a single terminal glucose to a protein that is not properly folded
Glucosyl transferase
49
Cytoslic degradation machinery
Proteasome
50
ER resident protein sequence
HDEL or KDEL
51
Protein coat used for Golgi -> PM and endocytosis
Clathrin
52
Protein coast used for intragolgi and retrograde Golgi -> ER
COPI
53
Protein coat for ER -> Golgi
COPII
54
Coat subunit that has enzymatic activity for COPI
ARF
55
Coat subunit that has enzymatic acitivty for COPII
SAR1
56
Stimulate GTPase activity and make it go faster
GAP (GTPase activating protein)
57
Molecule that initiates the formation of vescile budding on the ER membrane
SAR1
58
When SAR1 is off, where is its helix?
Tucked away
59
When SAR1 is on, where is its helix?
Exposed and inserted into phopholipid bilayer
60
How does SAR1 initiate budding?
Nucleates the binding of coat proteins
61
Two dimeric subunits of COPII coat
Sec23/Sec24
62
Interacts with integral membrane proteins that aids in the selection of membrane integral cargo receptors
Sec24
63
Forms a cage structure to deform the membrane and form a vesicle
Sec13/Sec31
64
What happens when SAR1 cleaves its GTP to GDP?
Leaves coated vesicle, starting a cascade that uncoats the vesicle
65
2 addressing systems for vesicles
Tethering, docking
66
How many proteins are in the complex involved in the tethering process?
5-10
67
Protein that mediates the communication between a vesicle and a membrane
Rab proteins
68
What kind of protein are Rab proteins?
G-protein
69
What does a Rab protein do exactly?
Tells SNARE proteins that a vesicle has been "tethered" and now able to "dock"
70
Responsible for the merger of two phospholipid bilayers
SNARE proteins
71
2 proteins involved in recycling SNARE proteins
Adapter SNAP and chaperone NSF
72
Forward traffic
Anterograde
73
Backwards traffic
Retrograde
74
How is the localization of the golgi in perinuclear region maintained?
Microtubules
75
Some proteins getting packaged into ER vesicles just because they are in the right place at the right time
Bulk Flow
76
How are ER resident proteins stopped from being packaged into vesicles for transport?
Aggregate themselves into too large of complexes for vesicles
77
Aggregation of ER proteins
Kin Recognition
78
Fusion of uncoated vesicles in between ER and cis-Golgi
Vesicular tubular clusters (VTC)
79
True or false: VTCs are unique to ER to golgi transport
True
80
Fusion of vesicular membranes
Homotypic fusion
81
Fusion of vesicular membrane to a organelle membrane
Heterotypic fusion
82
How are KDEL sequences recognized for retrograde transport?
Golgi membrane bound receptor
83
Motif for membrane bound residents that end up in the wrong place
KKXX
84
What is KKXX recognized by?
COPI coat machinery
85
How do KDEL receptors know when to unbind to its cargo?
Golgi is more acidic than ER, so releases in the more neutral environment of the ER
86
4 functions of golgi
Glycosylation, production of proteoglycans, protein sorting, sulfation
87
Specifically, what kind of glycosylation occurs in the golgi?
Modification of existing N-linked sugar, O-linked glycoslyation
88
4 functions of protein glycosylation
Aid in protein folding, surface coating, specific interactions, ECM
89
How does surface coating of glycosylated proteins help the protein
Protection from extracellular enivornment
90
2 classes of N-linked sugars
High mannose, complex
91
Where are high mannose sugars added?
ER
92
Where are complex sugars trimmed?
Golgi
93
What modifies complex sugars?
Glycosyltransferases
94
Example of a sugar with a negative charge
Sialic acid
95
What residues does o-linked sugar modification take place on?
Serine or threonine hydryoxyl residues
96
Primary degradative organelle of the cell
Lysosomes
97
Besides degradation, what other role does lysosomes play
Osmolyte storage
98
Role of vacuoles in a plant
OSmotic stability or turgor pressure
99
Sorting signal of proteins of secretory pathway to lysosomes
Mannose-6-phosphate sorting signal
100
What kind of singal is the Mannose-6-phosphate signal?
Signal patch
101
What is the mannose-6-phosphate sorting signal recognized by?
N-acetylglucosamine (GlcNAc) phosphotransferase in the cis-Golgi
102
How does GlcNAc-P work?
Binds high mannose and a UDP-GlcNAc and catalyzes transfer of GlcNAc phosphate to terminal mannose residue
103
How are GlcNAc sugars removed?
Glycosidase
104
What is the mannose 6-P tag recognized by?
Mannose 6-phosphate receptor (M6PR) in TGN
105
How are lysosome proteins released into the lysosome?
pH sensitivity (lysosome very acidic)

Cell Biology (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions