Pathways and Signaling

Question 1

Secretory Pathways: types

Answer 1

Facultative: cargo is stored in vesicles until signaled to be released/requires chemical signals

Constitutive: cargo secreted continuously/does not require a chemical signal

Question 2

Lysosomal Pathway: Signal, Location

Answer 2

mannose-6-phosphate enzyme

found in glycoproteins that will become acid hydrolases

Question 3

Types of Lysosomal Vesicles

Answer 3

Primary (recently budded from TGN)
Secondary (low pH: has fused with phagosome)
Residual Body (remnants of secondary lysosome with undigested material)
Early endosome (ph 7.3 to 7.4)
Late Endosomes (pH 5)

Question 4

Where would you find the NLS?

Answer 4

A signal molecule for proteins recently synthesized and destined for the nucleus

Question 5

What makes the NLS

Answer 5

consists of 4-8 amino acids with positive charge residues

Question 6

Fate of the NLS

Answer 6

Remains on protein

Question 7

N-terminal sequence is found where?

Answer 7

proteins destined for the mitochondria

Question 8

70 hsp does what?

Answer 8

chaperones proteins to mitochondria

Question 9

how does 70 hsp work?

Answer 9

keeps protein “unfolded” during transport

Question 10

the TOM complex

Answer 10

complex that allows new synthesized proteins to be transported into the mitochondria

Question 11

fate of N-terminal sequence

Answer 11

it is cleaved