BCH3021 Lecture Notes - Lecture 20: Retromer, Ldl Receptor, Phosphatidylinositol

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

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QUESTION 11

During skeletal muscle contraction, the roles of ATP include:

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QUESTION 12

One of the functions of smooth endoplasmic reticulum is

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QUESTION 13

The function of COP-II coated vesicles is mainly:

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QUESTION 14

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

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QUESTION 15

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

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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

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QUESTION 17

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

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QUESTION 18

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

True

False

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QUESTION 19

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

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QUESTION 20

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

29 Most proteins destined to enter the endoplasmic reticulum _________.

(a) are transported across the membrane after their synthesis is complete.

(b) are synthesized on free ribosomes in the cytosol.

(c) begin to cross the membrane while still being synthesized.

(d) are keep binding to Signal recognition particle (SRP) while they are translated.

30 Which of the following choices reflects the appropriate order of locations through which a protein destined for the plasma membrane travels?

(a) lysosome → endosome → plasma membrane

(b) ER → lysosome → plasma membrane

(c) Golgi → lysosome → plasma membrane

(d) ER → Golgi → plasma membrane

31 Which of the following statements about vesicle budding from the Golgi is false?

(a) COPII can initiate vesicle budding on Golgi membrane.

(b) Some vesicles budded from Golgi membranes move towards ER.

(c) Once vesicle budding completed, clathrin molecules are released from the vesicle.

(d) Clathrin molecules act at the cytosolic surface of the Golgi membrane.

32 Which of the following statements is false?

(a) The signal sequences on mitochondrial proteins are first bound to translocator on outer membrane after translation.

(b) Most mitochondrial proteins are not imported from the cytosol but are synthesized inside the mitochondria.

(c) Chaperone proteins in the mitochondria facilitate the movement of proteins across the outer and inner mitochondrial membranes.

(d) Mitochondrial proteins cross the membrane in their unfolded state.

Answer true or false for the following

a. NSF unwinds the v-SNARE/t-SNARE complex to allow membrane fusion during docking

b. Clathrin forms “cages” on vesicles that originate from plasma membrane.

c. Clathrin binds to adaptor proteins that link clathrin to membrane proteins.

d. Clathrin vesicles are used for endocytosis – bringing material across the plasma membrane and often delivering it to the early endosome

e. Clathrin mediates the fusion of the vesicles with early endosomes

f. Coated pits are formed from not wearing antiperspirant.

g. Rab (small GTPases) bound with GTP is critical for proper tethering of a vesicle/target organelle pair

h. Clathrin exhibits quaternary structure, defined by the assembly of three heavy chains and three light chains to form a triskelion

i. Compare to other filaments, only intermediate filaments have intrinsic ability to assembly and require no nucleation or assembly proteins