Lecture 4 - Membranes III: Transport

Question 1

Possible destinations of proteins translated by cytoplasmic ribosomes

Answer 1

Cytoplasm
Nucleus
Mitochondria
Peroxisomes

Question 2

Possible destinations of proteins translated in the ER

Answer 2

Plasma membrane
ER
Golgi
Lysosomes
Secretion

Question 3

Targeting pathologies

Answer 3

Neonatal Adrenoleukodystrophy (NALD)
Zellweger Syndrome (peroxisome targeting)
Huntington's Disease (nuclear targeting)

Question 4

Peroxisome targeting sequence

Answer 4

S-K-L

Question 5

Nuclear localization sequence (NLS)

Answer 5

Short (typically 5-6) basic amino acid sequence

Question 6

Lysosomal target molecule

Answer 6

Mannose-6-phosphate

Question 7

Mitochondrial targeting sequence

Answer 7

Long-ish (about 75) amino acid sequence near the N-terminus of the protein

Question 8

ER targeting sequence

Answer 8

K-D-E-L

Question 9

Microtubule functions

Answer 9

1. Cilia and flagella functions
2. Mitotic spindle
3. Organelle/cargo transport

Question 10

Microfilament functions

Answer 10

1. Phagocytosis
2. Cytokinesis
3. Cell motility
4. force generation (muscle)
5. membrane stabilization (RBC)

Question 11

Intermediate filament

Answer 11

Mechanical integrity (nucleus, cell-cell, cell-matrix)