Protein Targeting

Question 1

Nucleus

Answer 1

Nuclear localisation signal (surface of proteins, retained)
Folded in transport
Requires importin and Ran GTP
Requires GTP

Question 2

Mitochondrial matrix

Answer 2

Amphipathic signal (N-terminus, cleaved)
Partially unfolded by chaperones in transport
Requires Tom/Tim
Requires ATP

Question 3

Lysosomes

Answer 3

Mannose-6-phosphate (signal patch, removed by phosphatase)
Folded (delivered via vesicle)
Requires M-6-P receptor
Requires energy

Question 4

Retention in ER

Answer 4

KDEL (C-terminus, retained)
Folded (delivered via vesicle)
Requires KDEL receptor
Do not directly require energy

Question 5

ER

Answer 5

Signal sequence (N-terminus, cleaved)
Unfolded in transport
Requires SRP, SRP receptor, protein translocator
Requires GTP