Lecture 9: Cell & Molecular Biology of the Nervous System III

Question 1

secretory pathway

Answer 1

• “biosynthetic pathway”
• involved in synthesis and trafficking of integral membrane proteins and secreted cargoes
• components: ER, Golgi, late endosome, early endosome, lysosome, secretory vesicles

Question 2

What are some functions of the smooth ER?

Answer 2

• lipid synthesis and orientation
• Ca storage
• detoxification

Question 3

What are some functions of the rough ER?

Answer 3

• protein synthesis (transmembrane and secretory)
• core glycosylation
• Ca storage

Question 4

What are the 2 main functions of the Golgi?

Answer 4

modify and sort most ER products

Question 5

What are the 2 types of secretory pathways?

Answer 5

• constitutive secretory pathway

- regulated secretory pathway

Question 6

What do secretory vesicles contain?

Answer 6

proteins, neuropeptides, neurotrophic factors, transmembrane proteins

Question 7

Do neurotransmitters use either of the main secretory pathways?

Answer 7

no

Question 8

endosomal pathway

Answer 8

• involves early endosome, late endosome (MVB), lysosome, endocytic vesicle, recycling vesicle, and cell membrane
• functions in nutrient uptake, delivery of damaged proteins to lysosomes, and regulation of the number of proteins on cell surface

Question 9

Why is the early endosome important?

Answer 9

pre-synaptic early endosome generates synaptic vesicles

Question 10

What 2 organelles are involved in protein degradation?

Answer 10

• lysosomes

- proteasomes

Question 11

How is a lysosome different from a proteasome?

Answer 11

in general, lysosomes are more dedicated to membrane proteins, while proteasomes are more dedicated to soluble proteins

Question 12

protein fatty acylation

Answer 12

• covalent attachment of a fatty acid group on a protein
• how cytosol soluble proteins can interact with plasma membrane
• post-translational modification