Question

1. 1. What is the difference between a start-transfer sequence and a signal sequence
2. 1. What does a signal peptidase do?
   2. What happens to a signal sequence after it’s cleaved?
   3. What does it mean when the translocator is gated in two directions?

Answer 1

1. Start-transfer sequence
1. It is not present in N terminal sequence.
2. it is not cleaved after transfer of the protein.

signal sequence
1. It has 8 -14 hydrophobic amino acids at the N-terminal.
2. It is cleaved.

2. It is cleaved the N terminal signal peptides to form a mature protein.

3. Signal sequences are further cleaved or send to lysosomes.

4. Translocator open laterally to form gated in two directions,
to form a pore across the membrane to the hydrophilic portions of proteins cross the lipid bilayer.