🏷️ LIMITED TIME OFFER: GET 20% OFF GRADE+ YEARLY SUBSCRIPTION →
Log in
HomeClass Notes1,200,000CA670,000

BIO206H5 Lecture 20: BIO206 Lecture 20/22.pdf

122 views21 pages
skykoala223
1 Dec 2013
School
UTM
Department
Biology
Course
BIO206H5
Professor
George S Espie

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Signal sequence is required for transport into the nucleus. The sequence is generally 1-2 positively charged areas (lysine or arginine) - refer to table in your text. Initial interaction with the pores requires aid of nuclear import receptors - these bind and then interact with the fibrils, directing the protein into the pore. The pore opens just enough to allow the complex of protein and nir to enter, and then closes. Gtp hydrolysis is required for this change but the exact mechanism is still unknown. The nir dissociates in the nucleus and is transported back out of a nuclear pore to the cytoplasm (recycled) Nls - localization is in the body of the protein. This diagram is in your textbook and you can see the schematic shows the various steps. Protein binds, the complex is transported through, then they separate and the nuclear. Import receptor is recycled back out to the cytosol to collect another protein.

Get access

Grade+20% off
$8 USD/m$10 USD/m
Billed $96 USD annually
Grade+
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
40 Verified Answers
Class+
$8 USD/m
Billed $96 USD annually
Class+
Homework Help
Study Guides
Textbook Solutions
Class Notes
Textbook Notes
Booster Class
30 Verified Answers

Related textbook solutions

Molecular Cell Biology
8 Edition,
Lodish
ISBN: 9781464183393
Biology: Science for Life with Physiology
6 Edition,
Belk
ISBN: 9780134555430
Biology
2nd Edition, 2013
Openstax
ISBN: 9781947172517
Concepts of Biology
OER Edition,
Openstax
ISBN: 9781938168116
Essentials of Biology
5 Edition,
Mader
ISBN: 9781259660269

Related Documents

BIO206H5 Lecture Notes - Lecture 20: Nuclear Localization Sequence, Nuclear Transport, Active Transport
crimsonsnake651
BIO206H5
Final Exam
Study Guide
BIO206H5 Study Guide - Final Guide: Nuclear Export Signal, Endoplasmic Reticulum, Nuclear Localization Sequence
bronzerat622
BIO206H5 Lecture Notes - Lecture 10: Nuclear Localization Sequence, Nuclear Pore, Atp Hydrolysis
grayimpala213

Related Questions

True or False? True False
1. Proteins rapidly pass artificial membrane (liposome).--------------------------------------------------------------------------------------( ) ( )
2. Amphiphatic detergent such as SDS spontaneously forms bilayer inwater. ------------------------------------------------------------( ) ( )
3. Cholesterol does have a hydrophilic head and hydrophobic tail.-------------------------------------------------------------------------( ) ( )
4. Fat molecules are one of the major components of the plasmamembrane.------------------------------------------------------------- ( ) ()
5. Phospholipid molecules such as phosphatidylcholine spontaneouslyform bilayer. ----------------------------------------------------( ) ( )
6. Flippase facilitates lateral movement of phospholipids withinthe plane of the membrane.----------------------------------------- ( ) ( )
7. Glycolipids make bilayer less permeable to small water solublemolecules.----------------------------------------------------------- ( ) ()
8. Membrane inner leaflet is enriched with phosphatidylcholine,Sphingomyelin, and Glycolipid. -----------------------------------( ) ( )
9. Plasma membrane proteins can have an enzyme activity.--------------------------------------------------------------------------------( ) ( )
10. A single pass membrane protein must have an amphiphatic alphahelix.-------------------------------------------------------------- ( )( )
11. Plasma membrane proteins can be linked to a lipid molecule atthe outer leaflet of the plasma membrane. --------------------- ( )( )
12. The lateral motility of membrane proteins can be restricted bytight junctions.------------------------------------------------------ ( ) ()
13. Channel proteins have specific binding sites for ions and thusslower than carrier proteins.--------------------------------------- ( ) ( )
14. An antiport would function as a symport if its orientation inthe membrane were reversed. ---------------------------------------( ) ( )
15. A transmembrane pore can be formed by multiple amphipathicalpha helices. ----------------------------------------- ( ) ()
16. Porin proteins form water-filled channels in the outer membraneof a bacterium and are mostly composed of beta sheets. ---- ( ) ()
17. Glucose uniporters localize at the apical side of theintestinal epithelium.------------------------------------------------------------ ( ) ()
18. GAP junction is a selective pore for anions.-----------------------------------------------------------------------------------------------( ) ( )
19. A voltage-gated Na+ channel adopts only two conformationstates: open and closed.----------------------------------------------- ( ) ( )
20. Voltage gated K+ channel opens faster than the Voltage gatedNa+ channels.-------------------------------------------------------- ( ) ()
21. Opening of chloride channel at the synapse will help to fire anaction potential.------------------------------------------------------ ( ) ()
22. The nuclear pore complex forms a gate through which moleculespass the nucleus uni-directionally. -------------------- ( ) ()
23. A completely folded protein is imported into a mitochondrionthrough a large non-selective pore.--------------------------------- ( ) ( )
24. ER signal sequence contains multiple lysine and arginineresidues.----------------------------------------------------------------------( ) ( )
25. The plasma membrane is a sorting station of inward endocyticpathway.---------------------------------------------------------------- () ( )
26. The trans Golgi functions as a sorting station of outwardsecretory pathway.----------------------------------------------------------- ( ) ()
27. Vesicles budding from ER are coated with Clathrin.----------------------------------------------------------------------------------------( ) ( )
28. RabGTPases and tethering proteins are the major specificitydeterminant of vesicle transport system. --------------------------( ) ( )
29. v-SNARE proteins are one of the tethering proteins.------------------------------------------------------------------------------------( ) ( )
30. In secretory cells, the constitutive and regulatory pathways ofexocytosis diverge at the cis Golgi network. ------------------ ( )( )
31. Many proteins are posttranslationally glycosylated at tyrosineresidues in the ER.------------------------------------------------- ( ) ( )
32. Cells import LDL molecules exclusively through pinocytosis.-------------------------------------------------------------------------( ) ( )
33. Cells recycle LDL receptors from lysosome to the plasmamembrane.----------------------------------------------------------------- () ( )
34. Phagosomes fuse with late endosome.------------------------------------------------------------------------------------------------------( ) ( )
35. Small vesicles from ER near the plasma membrane can fuse withthe plasma membrane upon bypassing Golgi apparatus. -- ( ) ()
36. If a Sec mutant showed an accumulation of newly synthesizedproteins at ER,
then the Sec gene is likely a component of vesicle-buddingmachinery of trans-Golgi network.------------------------------------ ( ) ( )
37. A signal recognition particle is a single pass trans-membraneprotein of the ER membrane.---------------------------------------- ( ) ( )
38. Typical animals cells display higher levels of intracellularsodium than extracellular compartments.------------------------------ ( ) ( )
39. Typical animals cells display higher levels of intracellularchloride than extracellular compartments.----------------------------- ( ) ( )
40. The Na-K Pump is a GTPase that can adopt active and inactiveconformational states.----------------------------------------------- ( ) ( )
1. Phospholipase
C-­-ß
produces
phosphatidylinositol
3,4,5-­-trisphosphate
and
diacylglycerol.
(
)
(
)
2. PDGF
activates
GPCR.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­----­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
3. Rho
is
an
example
of
heterotrimeric
G
proteins.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­----­--­--­--­--­--­-
(
)
(
)
4. All
members
of
the
G
protein
coupled
receptors
interact
with
small
GTPase
Ras.
-­--­--­--­--­--­--­--­--­--­-
(
)
(
)
5. Adrenaline
is
an
example
of
the
ligands
for
the
RPTK
family.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
6. Ras
GEF
activates
RPTK.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­----­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
7. PH
domain
containing
proteins
bind
to
activated
EGFR.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
8. Ligands
for
GPCR
proteins
induce
dimerization
of
the
receptor.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
9. Grb2
is
an
adaptor
protein
that
binds
to
a
phospho-­-tyrosine
residue
of
activated
RPTK
through
a
PH
domain.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­----­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
10. When
a
cell
is
expressing
a
large
number
of
dominant
negative
EGFR
proteins,
an
introduction
of
a
constitutively
active
Ras
mutant
will
allow
EGF
signaling.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
11. PI3K
generates
phosphatidylinositol
3,4,5-­-trisphosphate
from
IP3.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
12. Calcium
inhibits
PKC.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­----­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
13. cAMP
activates
PKA.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­----­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
14. The
MAP
kinase
ERK
inhibits
MAP
kinase
kinases.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­----­--­-
(
)
(
)
15. cAMP
is
an
example
of
a
first
messenger.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­----­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
16. All
7-­-Transmembrane
receptors
are
G
Protein
Coupled
Receptors.
-­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
17. Both
Ga
and
Gß
subunits
of
the
heterotrimeric
G
protein
can
mediate
GPCR
signaling.
-­--­--­-
(
)
(
)
18. Both
Ga
and
Gß
subunits
of
the
heterotrimeric
G
protein
have
GTPase
activity.
-­--­--­--­--­--­--­--­--­--­--­--­-
(
)
(
)
19. The
Gas
subunit
of
the
heterotrimeric
G
protein
suppresses
the
function
of
Adenylyl
cylase.
(
)
(

1) The parasympathetic nervous system generally promotesdigestion. Innervation is via the vagus nerve. Ach binds tomuscarinic receptors. True or False?

2) Which of the following statements is correct?

a) The liver receives oxygenated blood from the hepatic arteryand deoxygenated blood from the hepatic portal vein. Branches ofboth veins carry blood into liver sinusoids. Hepatocytes absorboxygen, most of the nutrients, and some toxins. Needed substancesare secreted back into the blood. Blood then drains into thecentral vein and into a hepatic vein.

b) The liver receives deoxygenated blood from the hepatic arteryand oxygenated blood from the hepatic portal vein. Branches of bothveins carry blood into liver sinusoids. Hepatocytes absorb oxygen,most of the nutrients, and some toxins. Needed substances aresecreted back into the blood. Blood then drains into the centralvein and into a hepatic vein.

c) The liver receives oxygenated blood from the hepatic arteryand deoxygenated blood from the hepatic portal vein. Branches ofboth veins carry blood into liver central vein. Hepatocytes absorboxygen, most of the nutrients, and some toxins. Needed substancesare secreted back into the blood. Blood then drains into thesinusoids and into a hepatic vein.

d) The liver receives oxygenated blood from the hepatic arteryand deoxygenated blood from the hepatic portal vein. Branches ofboth veins carry blood into liver sinusoids. Kupffer cells absorboxygen, most of the nutrients, and some toxins. Needed substancesare secreted back into the blood. Blood then drains into thecentral vein and into a hepatic artery.

3) Regulation of secretion of saliva involves:

a) Parasympathetic and sympathetic stimulation

b)Action of the inferior and superior salivatory nuclei in themedulla

c)Activity of the myenteric plexus

d)Activity of the submucosal plexus

4) Bile formed in the liver is transported to the gall bladderfor storage through which pathway? (Some steps may be omitted)

a)Bile duct, right and left hepatic ducts, common hepatic duct,cystic duct

b)Common hepatic duct, right and left hepatic ducts, bile duct,cystic duct

c) Right and left hepatic ducts, bile ducts, common hepaticduct, cystic duct

d) Bile ducts, common hepatic duct, cystic duct, right and lefthepatic ducts

5)Which of the following statements is incorrect?

a)Sodium ions are transported out of absorptive cells bybasolateral sodium pumps.

b) Negatively charged ions follow sodium or are moved out byactive transport.

c)Most water soluble vitamins are absorbed by activetransport.

d) Water absorption in the GI tract involves osmosis

6) Insulin is needed for carbohydrate metabolism because it

a)is required for the breakdown of complex carbohydrates

b)transports glucose in the bloodstream.

c)acts as a glucose receptor molecule on the cell surface.

d) is part of an active transport mechanism required for entryof glucose into cells

e)increases the insertion of a particular type of glucosetransport protein into the cell membrane

The vesicles that transport materials from donor membranes to acceptor membranes include:

1.

COP-II coated vesicles
2.

COP-III coated vesicles
3.

COP-I coated vesicles
4.

Clathrin coated vesicles

2.5 points

QUESTION 11

During skeletal muscle contraction, the roles of ATP include:

1.

ATP is not required for forming the crossbridges between myosin and actin filaments.
2.

ATP is utilized as a structural linker to mediate the interaction between myosin and actin filaments
3.

Hydrolysis of ATP provides energy for myosin head to move along actin filaments and the binding of ATP to myosin head allows the detachment of myosin fromactin filaments.
4.

ATP binds to actin filaments to drive the power stroke of myosin head.

2.5 points

QUESTION 12

One of the functions of smooth endoplasmic reticulum is

1.

Synthesizing steroid hormone in the endocrine cells of the gonad and adrenal cortex
2.

Serves as the starting point of the biosynthetic pathway
3.

Synthesizing secretory proteins
4.

Degrading cell debris

2.5 points

QUESTION 13

The function of COP-II coated vesicles is mainly:

1.

Transporting materials from endosomes to Golgi complex
2.

Moving materials from the ER to the ERGIC and Golgi complex.
3.

Transporting materials from Golgi complex back to endoplasmic reticulum.
4.

Involved in receptor-mediated endocytosis.

2.5 points

QUESTION 14

Which of the following processes is completed in rough endoplasmic reticulum?

1.

Chaperones help misfolded proteins fold correctly.
2.

Proteins that target to nucleus are synthesized in rough endoplasmic reticulum.
3.

O-linked glycosylation occurs in rough endoplasmic reticulum.
4.

Misfolded proteins are destructed in rough endoplamic reticulum.

2.5 points

QUESTION 15

Kinesin is the motor protein that coorporates with microtubules. It has the following functions:

1.

It uses GTP as energy source.
2.

It can hydrolyze ATP and use the energy to drive cargo along microtubules from minus end to plus end.
3.

It has a globular head that can act as GTPase
4.

The tail of kinesin is more diverse and binds to cargo

2.5 points

QUESTION 16

For correct segregation and trafficking, lysosomal proteins are tagged in the cis-Golgi with phosphorylated mannose residues, and then the tagged lysosomal enzymes are recruited to clathrin coated vesicles by mannose 6-phosphate receptors.

True

False

2.5 points

QUESTION 17

The process that specialized cells, such macrophages, engulf relatively large particles is:

1.

Called pinocytosis
2.

Called phagocytosis
3.

Mediated by COP-II coated vesicles
4.

Called autophagy

2.5 points

QUESTION 18

Proteins synthesized on rough endoplasmic reticulum and smooth endoplasmic reticulum are imported co-translationally to their destinations

True

False

2.5 points

QUESTION 19

Treatment of cells with a drug that promotes microtubule disassembly disperses Golgi complex into separate stacks of membrane compartments, suggesting that:

1.

Golgi complex is made of microtubules.
2.

Microtubules are important for the organization of Golgi complex.
3.

Microtubules are transported into Golgi complex
4.

Golgi complex is composed of tubulin proteins

2.5 points

QUESTION 20

Which of the following is correct about signal sequence of a secretory protein?

1.

It is an “address codes” for protein trafficking pathways
2.

It is usually located at the C-terminus.
3.

It targets the ribosome and the protein that is being synthesized to endoplasmic reticulum.
4.

It is removed in Golgi complex.