Question 1

What phenotype would be observed in a cell containing a nonhydrolyzable form of ATP with respect to the vesicles of the secretory pathway?

Accepted Answer

A) Secretion of peptides from the cell would be increased. 
B) Vesicles would be delivered to incorrect target membranes. 
C) Uncoated vesicles would accumulate. 
D) Coated vesicles would accumulate. 
A) Secretion of peptides from the cell would be increased. 
B) Vesicles would be delivered to incorrect target membranes. 
C) Uncoated vesicles would accumulate. 
D) Coated vesicles would accumulate.

Question 2

Describe the types of mutations in the LDL receptor that would cause familial hypercholesterolemia.

Accepted Answer

A mutation that prevents the synthesis o

Question 3

If Sar1 is inserted into the membrane:

Accepted Answer

A) it is bound to GTP and recruits COPII coat proteins. 
B) it is bound to GDP and recruits COPII coat proteins. 
C) it is bound to GTP and recruits cargo. 
D) it is not bound to GTP or GDP. 
A) it is bound to GTP and recruits COPII coat proteins. 
B) it is bound to GDP and recruits COPII coat proteins. 
C) it is bound to GTP and recruits cargo. 
D) it is not bound to GTP or GDP.

Question 4

How are soluble,luminal ER proteins that "leak" out of the ER retrieved to the ER?

Accepted Answer

Soluble proteins of the ER have a Lys-As

Question 5

Yeast sec mutations:

Accepted Answer

A) provide little evidence regarding the mechanism,necessitating other assays or information. 
B) invariably affect nonessential genes. 
C) affect protein transport into mitochondria but not chloroplasts. 
D) all fall into the same complementation class. 
A) provide little evidence regarding the mechanism,necessitating other assays or information. 
B) invariably affect nonessential genes. 
C) affect protein transport into mitochondria but not chloroplasts. 
D) all fall into the same complementation class.

Question 6

Lipoproteins are effective in transporting lipid molecules in an aqueous environment because their surface layer is:

Accepted Answer

A) hydrophobic. 
B) glycosidic. 
C) amphipathic. 
D) hydrophobic and glycosidic. 
A) hydrophobic. 
B) glycosidic. 
C) amphipathic. 
D) hydrophobic and glycosidic.

Question 7

Which of the following is a forward transport sorting signal acting at the ER?

Accepted Answer

A) diacidic amino acid motif within the cytosolic domain 
B) KDEL (Lys-Asp-Glu-Leu)C-terminal sequence 
C) KKXX (Lys-Lys-X-X)within the cytosolic domain 
D) NPXY (Asn-Pro-X-Tyr)within the cytosolic domain 
A) diacidic amino acid motif within the cytosolic domain 
B) KDEL (Lys-Asp-Glu-Leu)C-terminal sequence 
C) KKXX (Lys-Lys-X-X)within the cytosolic domain 
D) NPXY (Asn-Pro-X-Tyr)within the cytosolic domain

Question 8

The first step in the secretory pathway that should be inhibited by a non-functional mutant of NSF is:

Accepted Answer

A) ER to Golgi transport. 
B) intra-Golgi transport. 
C) trans-Golgi network (TGN)transport to the plasma membrane. 
D) trans-Golgi network (TGN)transport to endosomes. 
A) ER to Golgi transport. 
B) intra-Golgi transport. 
C) trans-Golgi network (TGN)transport to the plasma membrane. 
D) trans-Golgi network (TGN)transport to endosomes.

Question 9

Which portion of a clathrin coat recognizes internalization signals such as Leu-Leu,Asn-Pro-X-Tyr,and Tyr-X-X- in the cytosolic domain of cell-surface endocytic receptors?

Accepted Answer

Adapter proteins of the AP2 class recogn

Question 10

The mannose 6-phosphate residue is important,as it is required to target soluble enzymes to the__________.The two enzymes responsible for attaching this residue onto these soluble enzymes reside in the ____________.

Accepted Answer

A) peroxisome;RER 
B) lysosome;cis-Golgi 
C) nucleus;medial-Golgi 
D) endosome;trans-Golgi 
A) peroxisome;RER 
B) lysosome;cis-Golgi 
C) nucleus;medial-Golgi 
D) endosome;trans-Golgi

Question 11

Professor George Palade's elegant experiment to follow protein synthesis and trafficking,published nearly 60 years ago,provided us with a great deal of information and has been used as a tool by several investigators.If you had access to all the reagents needed to repeat the in vitro experiment,describe what you would need to do to see the progression of newly synthesized proteins and their transport in the cell.

Accepted Answer

Expose pancreatic tissue slices to radio

Question 12

In MDCK cells,which of the following is a sorting signal that allows proteins to be targeted to the apical membrane?

Accepted Answer

A) GPI 
B) HA 
C) KDEL 
D) all of the above 
A) GPI 
B) HA 
C) KDEL 
D) all of the above

Question 13

The topogenic sequence of transferrin must include:

Accepted Answer

A) a signal sequence and an internal signal-anchor sequence. 
B) an internal signal-anchor sequence with positive charges N-terminal to the SA. 
C) an internal signal-anchor sequence with positive charges C-terminal to the SA. 
D) alternating signal-anchor sequences with stop-transfer sequences. 
A) a signal sequence and an internal signal-anchor sequence. 
B) an internal signal-anchor sequence with positive charges N-terminal to the SA. 
C) an internal signal-anchor sequence with positive charges C-terminal to the SA. 
D) alternating signal-anchor sequences with stop-transfer sequences.

Question 14

Receptor-mediated endocytosis of iron-carrying transferrin results in:

Accepted Answer

A) release of iron and proteolysis of the transferrin protein for recycling inside the cell. 
B) transferrin/transferrin receptor complexes in the cytosol of the cell. 
C) release of iron from the endosome to the cytosol. 
D) vesicle formation at the plasma membrane mediated by COP proteins. 
A) release of iron and proteolysis of the transferrin protein for recycling inside the cell. 
B) transferrin/transferrin receptor complexes in the cytosol of the cell. 
C) release of iron from the endosome to the cytosol. 
D) vesicle formation at the plasma membrane mediated by COP proteins.

Question 15

How are SNARE proteins thought to bring about specific membrane fusion?

Accepted Answer

SNARE proteins are thought to bring abou

Question 16

Protein sorting of anterograde cargo to different destinations within the Golgi complex occurs in the:

Accepted Answer

A) cis-Golgi. 
B) medial-Golgi. 
C) trans-Golgi. 
D) trans-Golgi network. 
A) cis-Golgi. 
B) medial-Golgi. 
C) trans-Golgi. 
D) trans-Golgi network.

Question 17

Proteins that function in the ER will encounter which of the following?

Accepted Answer

A) enzymatic modification of the ER resident soluble protein to add the KDEL sequence 
B) release from KDEL receptor binding in the Golgi due to a pH change 
C) anterograde transport in COPII coated vesicles 
D) sequestration in the ER by KDEL receptors 
A) enzymatic modification of the ER resident soluble protein to add the KDEL sequence 
B) release from KDEL receptor binding in the Golgi due to a pH change 
C) anterograde transport in COPII coated vesicles 
D) sequestration in the ER by KDEL receptors

Question 18

Why is VSV G protein one of the more useful tools in analyzing membrane trafficking?

Accepted Answer

The usefulness of VSV G protein resides

Question 19

Formation of the late endosome/multivesicular endosome occurs by mechanisms similar to those of:

Accepted Answer

A) exocytosis of insulin in response to glucose levels in the blood. 
B) GCA protein-mediated budding at the trans-Golgi network. 
C) retrovirus budding from the plasma membrane. 
D) none of the above 
A) exocytosis of insulin in response to glucose levels in the blood. 
B) GCA protein-mediated budding at the trans-Golgi network. 
C) retrovirus budding from the plasma membrane. 
D) none of the above

Exam 13: Vesicular Traffic, Secretion, and Endocytosis

What phenotype would be observed in a cell containing a nonhydrolyzable form of ATP with respect to the vesicles of the secretory pathway?

Describe the types of mutations in the LDL receptor that would cause familial hypercholesterolemia.

If Sar1 is inserted into the membrane:

How are soluble,luminal ER proteins that "leak" out of the ER retrieved to the ER?

Yeast sec mutations:

Lipoproteins are effective in transporting lipid molecules in an aqueous environment because their surface layer is:

Which of the following is a forward transport sorting signal acting at the ER?

The first step in the secretory pathway that should be inhibited by a non-functional mutant of NSF is:

Which portion of a clathrin coat recognizes internalization signals such as Leu-Leu,Asn-Pro-X-Tyr,and Tyr-X-X- in the cytosolic domain of cell-surface endocytic receptors?

The mannose 6-phosphate residue is important,as it is required to target soluble enzymes to the__________.The two enzymes responsible for attaching this residue onto these soluble enzymes reside in the ____________.

In MDCK cells,which of the following is a sorting signal that allows proteins to be targeted to the apical membrane?

The topogenic sequence of transferrin must include:

Receptor-mediated endocytosis of iron-carrying transferrin results in:

How are SNARE proteins thought to bring about specific membrane fusion?

Protein sorting of anterograde cargo to different destinations within the Golgi complex occurs in the:

Proteins that function in the ER will encounter which of the following?

Why is VSV G protein one of the more useful tools in analyzing membrane trafficking?

Formation of the late endosome/multivesicular endosome occurs by mechanisms similar to those of:

Chemical Foundations

Molecular Genetic Techniques

Protein Structure and Function

Culturing and Visualizing Cells

Fundamental Molecular Genetic Mechanisms

Bio-membrane Structure

Genes Genomics and Chromosomes

Transcriptional Control of Gene Expression

Post-Transcriptional Gene Control

Transmembrane Transport of Ions and Small Molecules

Cellular Energetics

Moving Proteins Into Membranes and Organelles

Signal Transduction and G-Protein Coupled Receptors

Signaling Pathways That Control Gene Activity

Cell Organization and Movement I: Microfilaments

Cell Organization and Movement II: Microtubules and Intermediate Filaments

Regulating the Eukaryotic Cell Cycle

Integrating Cells Into Tissues

Cell Birth, Lineage, and Death

Nerve Cells

Immunology

Cancer

Filters

The mannose 6-phosphate residue is important,as it is required to target soluble enzymes to the.The two enzymes responsible for attaching this residue onto these soluble enzymes reside in the __.